JP4037749B2 - Ink adjustment amount instruction method, ink adjustment amount instruction device, and ink adjustment amount instruction program - Google Patents

Description

【０１０５】
に従ってＣ′を求める。この（２）式中、Ｘ１００はカラープロファイルによって（Ｃ，Ｍ，Ｙ，Ｋ）＝（１００％，０％，０％，０％）に対応づけられたＣＩＥＸＹＺのうちのＸの値であり、Ｘ０は、同じカラープロファイルによって（Ｃ，Ｍ，Ｙ，Ｋ）＝（０％，０％，０％，０％）に対応づけられたＣＩＥＸＹＺのうちのＸの値である。ここで、（１）式に従って求めたＣ′を、（１）式中のＸの値をカラープロファイルを参照して求めた際のＣに対応づける。例えば（Ｃ，Ｍ，Ｙ，Ｋ）＝（２０％，０％，０％，０％）を基にカラープロファイルを参照してＸ２０を求め、（１）式に従って、
【０１０６】
【数２】

【０１０７】
が求められた場合、Ｃ＝２０％とＣ′＝２４％とを対応づける。このときのＣ＝２０％は、ドットゲインを算入する前の画像データ上の網％、Ｃ′＝２４％は、ドットゲインを算入した後の網％である。
【０１０８】
Ｃ（シアン）のみでなく、Ｍ（マゼンタ），Ｙ（イエロー），Ｋ（墨）についても同様であり、Ｍ（マゼンタ）については、Ｃ＝Ｙ＝Ｋ＝０％に固定するとともにＭ＝０％，１０％，２０％，…，１００％と変化させカラープロファイルを参照してＣＩＥＸＹＺのうちのＹを求め、
【０１０９】
【数３】

【０１１０】
但し、Ｙ１００，Ｙ０は、Ｍ＝１００％，０％（Ｃ＝Ｙ＝Ｋは常に０％）のときのＣＩＥＸＹＺのうちのＹの値である。
に従ってドットゲイン算入後のＭ′を求めて、ドットゲイン算入前のＭと算入後のＭ′とを対応づけ、Ｙ（イエロー）については、Ｃ＝Ｍ＝Ｋ＝０％に固定するとともにＹ＝０％，１０％，２０％，…，１００％と変化させカラープロファイルを参照してＣＩＥＸＹＺのうちのＺの値を求め、
【０１１１】
【数４】

【０１１２】
但し、Ｚ１００，Ｚ０は、Ｙ＝１００％，０％（Ｃ＝Ｍ＝Ｋは常に０％）のときのＣＩＥＸＹＺのうちのＺの値である。
に従ってドットゲイン算入後のＹ′を求めて、ドットゲイン算入前のＹと算入後のＹ′とを対応づけ、Ｋ（墨）については、Ｃ＝Ｍ＝Ｙ＝０％に固定するとともにＫ＝０％，１０％，２０％，…，１００％と変化させカラープロファイルを参照してＣＩＥＸＹＺのうちのＹの値を求め、
【０１１３】
【数５】

【０１１４】
但し、Ｙ１００，Ｙ０は、Ｋ＝１００％，０％（Ｃ＝Ｍ＝Ｙは常に０％）のときのＣＩＥＸＹＺのうちのＹの値である。
に従ってドットゲイン算入後のＫ′を求めて、ドットゲイン算入前のＫと算入後のＫ′とを対応づける。
【０１１５】
図１１のステップＳ３１では、このようにして、ＣＭＹＫ色空間上での、ドットゲイン算入前の画像データ上の座標値からドットゲイン算入後の座標値への写像関係が求められる。この写像関係も、図６，図７に示すコンピュータ５１０に記憶される（図９に示す記憶部７１０の写像関係７１０ｂ）。
【０１１６】
尚、ここでは、ステップＳ１１で求めたカラープロファイルを参照して、計算上でドットゲイン算入前後の写像関係を求めたが、上述の画像データ（例えばＣ（シアン）に関してはＭ＝Ｙ＝Ｋ＝０％に固定してＣ＝０％，１０％，２０％，…，１００％と変化させた複数の単色パッチを表わす画像データ。Ｍ，Ｙ，Ｋについても同様）に基づく単色パッチを印刷機で印刷しその印刷用紙上にあらわれた単色パッチの網点面積率を測定することによりドットゲイン算入後のＣ′，Ｍ′，Ｙ′，Ｋ′を求め、ドットゲイン算入前の画像データ上のＣ，Ｍ，Ｙ，Ｋと実測により求めたドットゲイン算入後のＣ′，Ｍ′，Ｙ′，Ｋ′とを対応づけることにより、ドットゲイン算入前後の写像関係を求めてもよい。
【０１１７】
以上の各ステップＳ１１，Ｓ１２，Ｓ２１，Ｓ３１は準備段階のステップであり、このような準備が終了した後、実際の画像印刷の場面に移る。
【０１１８】
ここでは、図６に示すように、実際に必要な印刷画像Ｐ１のほか、印刷用紙Ｐの余白の、各インクキーに対応した位置に、その印刷画像Ｐ１にとって重要な中間調のグレーパッチＰ２が印刷される。これらのグレーパッチＰ２には、前述したように、ＣＭＹの３色のインクが重畳された、例えばＣ＝Ｍ＝Ｙ＝５０％のＣＭＹグレーパッチと、Ｋの単色インクからなる、例えばＫ＝５０％のＫグレーパッチが含まれている。これらのグレーパッチＰ２は、印刷用紙ＰのそれらのグレーパッチＰ２が測色計５００の位置を通過するときにその測色計５００によって測定されＣＩＥＸＹＺ値が求められる（図１１ステップＳ４１ａ，Ｓ４１ｂ）。
【０１１９】
このＣＩＥＸＹＺ値は、図６に示すコンピュータ５１０に伝送されて図９のＸＹＺ取得部７２０で取り込まれる。
【０１２０】
そのコンピュータ５１０内では、図９に示す記憶部７１０に記憶されたカラープロファイル７１０ａが参照され、ＸＹＺ取得部７２０で取得したＣＩＥＸＹＺ値のうちの、ＣＭＹグレーパッチを測定して得たＸＹＺ値から、Ｋ＝０％の拘束条件の下でデバイス信号（ＣＭＹＫ色空間上の座標値）であるＣＭＹ値が算出され（ステップＳ４２ａ）、また、Ｋグレーパッチを測定して得たＸＹＺ値から、Ｃ＝Ｍ＝Ｙ＝０％の拘束条件の下でデバイス信号Ｋが算出される（ステップＳ４２ｂ）このデバイス信号ＣＭＹＫの算出の際、測色計５００での測色により得られたＣＩＥＸＹＺ値からデバイス信号ＣＭＹＫを求めるだけでなく、それと同様にして、その測色計５００で測定する対象であるグレーパッチの目標となるＣＩＥＸＹＺ値も、その同じカラープロファイルに基づいてデバイス信号ＣＭＹＫ＿ｔａｒに変換される。ここで‘＿ｔａｒ’は目標（ターゲット）であることを示す添字である。
【０１２１】
尚、この目標値としてのデバイス信号ＣＭＹＫ＿ｔａｒは、グレーパッチを作成するため用いた画像データそのものであり、その画像データ自体を記憶しておいたときは、目標ＣＩＥＸＹＺからＣＭＹＫ＿ｔａｒへの変換は不要である。
【０１２２】
次に、コンピュータ５１０内では、このようにして求めたデバイス信号ＣＭＹＫおよびＣＭＹＫ＿ｔａｒの双方について図９の記憶部７１０に記憶された写像関係７１０ｂ（図１０（Ｂ）にシアン（Ｃ）に関しその一例を示す）に基づいて、ドットゲイン補正が行なわれ、ドットゲインを含んだ補正デバイス信号Ｃ′Ｍ′Ｙ′Ｋ′，Ｃ′Ｍ′Ｙ′Ｋ′＿ｔａｒが算出される（ステップＳ４３ａ，Ｓ４３ｂ）。これらのステップＳ４３ａ，Ｓ４３ｂの処理は、図９に示すインク補正量指示装置７００のべた濃度算出部７３０を構成するドットゲイン算入部７３１での処理である。
【０１２３】
次に、ステップＳ４４ａ，Ｓ４４ｂでは、ドットゲインを含んだ補正デバイス信号Ｃ′Ｍ′Ｙ′Ｋ′，Ｃ′Ｍ′Ｙ′Ｋ′＿ｔａｒから濃度値が算出される。ここでは、補正デバイス信号から濃度値を求めるにあたっては、以下のマーレー・デービスの式を採用する。目標ＣＩＥＸＹＺから求めたデバイス信号ＣＭＹＫ＿ｔａｒにドットゲインを算入した補正デバイス信号Ｃ′Ｍ′Ｙ′Ｋ′＿ｔａｒのうちのシアンＣ′＿ｔａｒについて示すと、
【０１２４】
【数６】

【０１２５】
である。ここでＤ_c１００は、印刷機がインクキーの開度を含め全て標準状態にあるときの網点面積率１００％のシアン（Ｃ）の単色パッチのべた濃度である。このべた濃度Ｄ_c１００は、図１１のステップＳ２１で求められて図９の記憶部７１０に記憶されている対応関係７１０ｃ（インク塗布厚を調整するためのインクキーの開度の設定値とべた濃度との対応関係）中に含まれる、インクキーが標準の開度に設定されているときの単色パッチのべた濃度である。
【０１２６】
上記（６）式に基づいて、ドットゲインを含んだ補正デバイス信号Ｃ′＿ｔａｒが濃度値Ｄ_cp＿ｔａｒに換算される。
【０１２７】
また、これと同様に、図６に示すグレーパッチＰ２を測定して得た測定ＣＩＥＸＹＺから求めたデバイス信号ＣＭＹＫにドットゲインを算入した補正デバイス信号Ｃ′Ｍ′Ｙ′Ｋ′についても、補正デバイス信号Ｃ′について示すと、
【０１２８】
【数７】

【０１２９】
に従って補正デバイス信号Ｃ′に対応する濃度値Ｄ_cpが求められる（ステップＳ４４ａ）。
【０１３０】
ここで、補正デバイス信号Ｃ′は、補正デバイス信号Ｃ′＿ｔａｒと比べ一般に異なる網％値を示すが、網％値が変化したのは見かけ上であって実際上はインク塗布厚が変化したことによる濃度変化であり、網点面積率は一定であると考えられる（実際には、インク塗布厚が変化すると印刷画像上での網点面積率も若干は変化するが、その変化は小さいと考えられる）。
【０１３１】
そこで、ここでは、（６）式と（７）式から算出した２つの濃度値Ｄ_cp＿_tar，Ｄ_cpから、補正デバイス信号Ｃ′＿ｔａｒ，Ｃ′が相互に同一と見なして（Ｃ′＿ｔａｒ＝Ｃ′）、印刷機の現在の状態におけるべた濃度値Ｄ_c１００′を求める（ステップＳ４５ａ）。
【０１３２】
【数８】

【０１３３】
以上の（６）〜（８）式の演算はシアン（Ｃ）に関するものであるが、マゼンタ（Ｍ），イエロー（Ｙ），墨（Ｋ）についても同様である。
【０１３４】
すなわち、マゼンタ（Ｍ）については、
【０１３５】
【数９】

【０１３６】
【数１０】

【０１３７】
但し、Ｄ_M１００は、印刷機がインクキーの開度を含め標準状態にあるときのマゼンタの網点面積率１００％の単色パッチのべた濃度である。
に基づいて、Ｍ′＿ｔａｒ，Ｍ′にそれぞれ対応した濃度値Ｄ_MP＿_tar，Ｄ_MP＿が算出され（ステップＳ４４ａ）、式
【０１３８】
【数１１】

【０１３９】
に従って、印刷機の現在の状態におけるべた濃度値Ｄ_M＿１００′が算出される（ステップＳ４５ａ）。
【０１４０】
また、イエロー（Ｙ）については、
【０１４１】
【数１２】

【０１４２】
【数１３】

【０１４３】
但し、Ｄ_Y１００は、印刷機がインクキーの開度を含め標準状態にあるときのイエローの網点面積率１００％の単色パッチのべた濃度である。
に基づいて、Ｙ′＿ｔａｒ，Ｙ′にそれぞれ対応した濃度値Ｄ_YP＿_tar，Ｄ_YPが算出され（ステップＳ４４ａ）、式
【０１４４】
【数１４】

【０１４５】
に従って、印刷機の現在の状態におけるべた濃度値Ｄ_Y＿１００′が算出される（ステップＳ４５ａ）。
【０１４６】
さらに、墨（Ｋ）についても、
【０１４７】
【数１５】

【０１４８】
【数１６】

【０１４９】
但し、Ｄ_K１００は、印刷機がインクキーの開度を含め標準状態にあるときの墨（Ｋ）の網点面積率１００％の単色パッチのべた濃度である。
に基づいて、Ｋ′＿ｔａｒ，Ｋ′にそれぞれ対応する濃度値Ｄ_KP＿_tar，Ｄ_KPが算出され（ステップＳ４４ｂ）、式
【０１５０】
【数１７】

【０１５１】
に従って、印刷機の現在の状態におけるべた濃度値Ｄ_K＿１００′が算出される（ステップＳ４５ｂ）。これらステップＳ４４ａ，Ｓ４４ｂ，Ｓ４５ａ，Ｓ４５ｂの処理は、図９に示すインク調整量指示装置７００のべた濃度算出部７３０を構成するべた濃度推定部７３２で行われ、上記の（６）〜（１７）式に従って、印刷機の現在の状態におけるべた濃度の推定値Ｄ_C１００′，Ｄ_M１００′，Ｄ_Y１００′，Ｄ_K１００′が求められる。
【０１５２】
前述したように、図６に示すグレーパッチＰ２には、インクキーの配列数と同数のＣＭＹグレーパッチＰ２１とやはりインクキーの配列数と同様のＫグレーパッチＰ２２が含まれており、ステップＳ４１ａ，Ｓ４１ｂ〜ステップＳ４５ａ，Ｓ４５ｂの処理は、配列された複数のインクキー（図６に示す一色分のインクキー４１１ａ，４１１ｂ，…，４１１ｎを参照）のそれぞれについて行なわれ、Ｃ，Ｍ，Ｙ，Ｋの各色インクかつ配列された各インクキーについてべた濃度の推定値が求められる。
【０１５３】
図１１のステップＳ４６では、ステップＳ２１で求められた対応関係、すなわち、図９のインク調整量指示装置７００の記憶部７１０に記憶された対応関係７１０ｃ（図１０（ｃ）参照）に基づいて、べた濃度の推定値からインクキーの調整値Ｍが求められる。
【０１５４】
このインクキーの調整値Ｍは、１色のインクの１つのインクキーについて、
Ｍ＝ｆ（Ｄ１００´，Ｄ１００）……（１８）
と表現することができる。ここで、Ｍは、その１色のインクのその１つのインクキーの調整値、Ｄ１００´は、その１色のインクのその１つのインクキーに対応するべた濃度の推定値、Ｄ１００は、インクキーの開度の設定値を含めその印刷機の全てが標準状態にあるときの、その１色のインクのその１つのインクキーに対応するべた濃度の測定値である。
【０１５５】
図１２は、図９のインク調整量指示装置７００の記憶部７１０に記憶された対応関係７１０ｃ、すなわち、べた濃度とインクキーの開度の設定値との対応関係を示す図である。
【０１５６】
図１１のステップＳ４６では、上記（１８）式に示すように、べた濃度の推定値Ｄ１００′と標準状態にあるときのべた濃度値Ｄ１００との双方に基づいて、標準状態におけるべた濃度と同一のべた濃度を得られるようにインクキーの開度を調整するための調整値Ｍが求められる。このステップＳ４６の処理は、図９のインク調整量指示装置７００の調整値算出部７４０に相当する。
【０１５７】
このステップＳ４６における調整値Ｍの算出は、ＣＭＹＫの各色インクごとかつ各インクキーごとに行なわれる。
【０１５８】
図１１のステップＳ４７（図９のインク調整量指示装置７００の調整値指示部７５０）では、ステップＳ４６（図９のインク調整量指示装置７００の調整値算出部７４０）で求められる調整値Ｍがコンピュータ５１０の表示画面上に表示されるとともに、ＣＭＹＫの各色インクに対応したインクキー制御部（図６には一色分のインクキー制御部４１８が示されている）に送られてＣＭＹＫの各色インクの各インクキーの開度が調整される。
【０１５９】
図１３は、図６，図７に示すコンピュータ５１０の表示画面５３０ａ上に表示されるインクキー開度調整値Ｍを示す図である。
【０１６０】
ここには、ＣＭＹＫの各色インクごと、かつ各インクキー（ここでは番号１〜番号１３の１３のインクキー）ごとの調整値Ｍが示されている。「＋０」は、そのインクキーの開度は今のままでよいことを表わしており、「＋１」はそのインクキーの開度を＋１ステップだけ調整すべきことを表わしており、「−１」はそのインクキーの開度を−１ステップだけ調整すべきことを表わしている。「＋２」，「−２」等も同様である。
【０１６１】
尚、本実施形態では、今のインクキーの開度を「＋０」とし、今の開度からの相対的な調整値（「＋１」、「−２」等）を表示するように構成したが、今の開度からの相対値ではなく例えばインクキー全閉を基準としたときのインクキーの開度の絶対的な値を求めて表示してもよい。
【０１６２】
本実施形態では、上述したように、各インクキーの開度の調整値が表示されるたけでなく、それらの調整値がＣＭＹＫの各色インクごとのインクキー制御部（図６のインクキー制御部４１８参照）に送られて各インクキーの開度が調整される。
【０１６３】
ただし、図９のインク調整量指示装置７００の調整値指示部７５０では、図１３に示すように他コンピュータ５７０の表示画面上に調整値を表示することによってオペレータに向けて指示するにとどめ、図６のインクキー制御部４１８等、ＣＭＹＫの各色インクに対応するインクキー制御部に向けたインクキー開度指令の発信はオペレータに委ねてもよい。
【０１６４】
次に、インクキー開度のみでなく、インクキー開度とともにロールの回転速度を制御することによりインク塗布厚を調整する場合について説明する。
【０１６５】
この場合、図１１のステップＳ２１において、標準状態にある印刷機を用い、インクキーの開度だけでなくロール（図６のロール４１２に相当する、ＣＭＹＫの各色インク供給用の各ロール）の回転速度を標準状態から変化させて、ＣＭＹＫ各色インクの単色のべた（網点面積率１００％）の単色パッチを印刷し、それらの各単色パッチの濃度を測定し、べた濃度とインクキー開度の設定値との対応関係（図１２参照）のみでなく、べた濃度とロールの回転速度設定値との対応関係をＣＭＹＫの各色インクごとに求める。これらの対応関係は、図９の記憶部７１０に記憶しておく。
【０１６６】
図１４は、べた濃度とロール回転速度設定値との間の、一色分の対応関係を示す概念図である。
【０１６７】
ロールの回転速度とインクキーの開度との双方を調整することによりインク塗布厚を調整するときは、各インクキーに対応するべた濃度の推定値（図１１のステップＳ４５ａ，Ｓ４５ｂ（図９のべた濃度算出部７３０）で算出された推定値）を、各ロールに対応する一連のインクキー（例えば図６に示すロール４１２に対応する一連のインクキー４１１ａ，４１１ｂ，…，４１１ｎ）に関するべた濃度推定値の平均値Ｄ１００′_aveを求めて、そのべた濃度推定値の平均値Ｄ１００′_aveと印刷機がインクキーの開度およびロールの回転速度も含めて標準状態にあるときのべた濃度Ｄ１００とに基づいて図１４に示す回転速度補正値Ｍ′を求める。また、そのロールに対応する各インクキーについては、べた濃度推定値Ｄ１００′を以下のようにして新たな推定値に補正する。
【０１６８】
新たな推定値Ｄ１００′＝
元々の推定値Ｄ１００′−（Ｄ１００′_ave−Ｄ１００） ……（１８）
個々のインクキーについては、この（１８）式に基づいて求めた新たな推定値Ｄ１００′を用い、図１２に示すようなべた濃度とインクキー設定値との対応関係からインクキーの調整値Ｍを求める。
【０１６９】
図１１のステップＳ４７（図９の調整値指示部７５０）では、上記のようにして求めたＣＭＹＫの各色インクに対応するロール回転速度の各調整値Ｍを、ＣＭＹＫの各色インクに対応する各ロールの回転速度を制御する各ロール速度制御部（図６の一色分の構成におけるロール速度制御部４１７参照）に送って各ロールの回転速度を調整させるとともに各インクキーの各調整値Ｍを、ＣＭＹＫに対応する調整値Ｍごとにそれらの各色インクに対応する各インクキー制御部（図６の一色分の構成におけるインクキー制御部４１８参照）に送って各インクキーの開度を調整させる。また、それとともに、コンピュータ５１０の表示画面上に、図１３に示す各インクキーの調整値を表示するとともにロール回転速度の調整値を表示する。
【０１７０】
図１５は、ロール回転速度調整値の表示例を示す図である。
【０１７１】
ここには、ＣＭＹＫの各色インクの塗布を担当する各ロールについて、それぞれ、回転速度２．０ステップを上げるべきこと、回転速度１．０ステップを上げるべきこと、回転速度２．０ステップを下げるべきこと、および回転速度１．０ステップを上げるべきこと、が示されている。
【０１７２】
ここまで説明してきた実施形態の場合、べた濃度と設定値との対応関係を求めておき、中間調のグレーパッチの測色値からべた濃度の推定値を求め、そのべた濃度の推定値からインク塗布厚調整のための調整値を求めており、この場合、中間調のグレーパッチの網点面積率はその印刷画像の特質に応じて変更することができる。
【０１７３】
次に、図８〜図１５を参照して説明してきた第１実施形態に代わる本発明の第２実施形態について説明する。
【０１７４】
図１６は、ＣＤ−ＲＯＭに記憶された本発明の第２実施形態としてのインク調整量指示プログラムの模式構成図である。
【０１７５】
このＣＤ−ＲＯＭ５７０には、記憶部８１０、ＸＹＺ取得部６２０、座標写像部８３０、調整値算出部８４０、および調整値指示部８５０からなるインク調整量指示プログラム８００が格納されている。
【０１７６】
ここでは、この図１６に示すインク調整量指示プログラム８００を記憶したＣＤ−ＲＯＭ５１０が、図６、図７に示すコンピュータ５１０のＣＤ−ＲＯＭドライブ５２５に装填され、そのＣＤ−ＲＯＭ５７０に記憶されたインク調整量指示プログラムがそのコンピュータ５１０にアップロードされてハードディスク装置５２３に記憶される。このハードディスク装置５２３に記憶されたインク調整量指示プログラム８００が図７に示すメモリ５２２に展開されてＣＰＵ５２１で実行されると、このコンピュータ５１０は、本発明の第２実施形態としてのインク調整量指示装置として動作する。
【０１７７】
図１６に示すインク調整量指示プログラム８００の各部８１０〜８５０の作用については後述する。
【０１７８】
図１７は、本発明の第２実施形態としてのインク調整量指示装置を示す機能ブロック図である。
【０１７９】
図１７に示すインク調整量指示装置９００は、図６、図７に示すコンピュータ５１０に図１６に示すインク調整量指示プログラム８００がインストールされて実行されることによりそのコンピュータ５１０内に構築されるものである。
【０１８０】
図１７に示すインク調整量指示装置９００は、記憶部９１０と、ＸＹＺ取得部９２０と、座標写像部９３０と、調整値算出部９４０と、調整値指示部９５０とから構成されている。
【０１８１】
この図１７に示すインク調整量指示装置９００を構成する、記憶部９１０、ＸＹＺ取得部９２０、座標写像部９３０、調整値算出部９４０、および調整値指示部９５０は、図１６に示すインク調整量指示プログラム８００を構成する、それぞれ、記憶部８１０、ＸＹＺ取得部８２０、座標写像部８３０、調整値算出部８４０、および調整値指示部８５０に対応するが、図１７のインク調整量指示装置９００の各部９１０〜９５０は、コンピュータ５１０のハードウェアと、オペレーティングシステム（ＯＳ）と、アプリケーションプログラムとの複合で構成されているのに対し、図１６のインク調整量指示プログラム８００の各部８１０〜８５０は、それらのうちのアプリケーションプログラムの部分のみから構成されている。図１６のインク調整量指示プログラム６００がコンピュータ５１０にインストールされて実行されるときの、そのインク調整量指示プログラム８００の各部８１０〜８５０の作用は、図１７に示すインク調整量指示装置９００の各部９１０〜９５０の作用そのものであり、以下、図１７のインク調整量指示装置７００の各部７１０〜７５０の作用を説明することで、図１６のインク調整量指示プログラム８００の各部８１０〜８５０の作用の説明を兼ねるものとする。
【０１８２】
尚、ここでも前述の第１実施形態の場合と同様、図１７のインク調整量指示装置９００の各部９１０〜９５０の作用を説明するにあたってもその概要を説明するにとどめ、その詳細は、図１８、図１９を参照しての、本発明の第２実施形態としてのインク調整量指示方法の説明と合わせて説明する。
【０１８３】
図１７に示すインク調整量指示装置９００は、ＣＭＹＫの各色インクの塗布厚を調整しながら、図５、図６に示す印刷用紙上に網点の印刷画像を出力する印刷機を用いてその印刷用紙Ｐ上に網点の印刷画像を出力する際の、ＣＭＹＫの各色インクの塗布厚を調整するための各調整値を指示する装置である。ここで、各色インクの塗布厚は、前述したように、図６に示すインクキー４１１ａ，４１１ｂ，…，４１１ｎの開度やロール４１２の回転速度を調整することによって行なわれる（図６には、ＣＭＹＫのうちの一色分の構成のみ示されている）。
【０１８４】
ここで、図１７のインク調整量指示装置９００の記憶部９１０には、カラープロフィル９１０ａと、対応関係９１０ｂとが記憶されている。
【０１８５】
カラープロファイル９１０ａは、図２を参照して説明した印刷プロファイルに相当するものであり、各色インクＣＭＹＫの網点面積率を座標軸とするデバイス色空間（ここではＣＭＹＫ色空間）上の座標値と、その座標値に対応づけられた画像データに基づいて、印刷機が所定の標準状態（各所定の色インクや所定の印刷用紙が用いられ、その印刷機の各部やその環境温湿度等が所定の標準の状態に設定された状態）にあるときにその印刷機で出力される印刷画像上の色を表わす、所定の共通色空間（ここではＣＩＥＸＹＺ色空間）上の座標値とを対応づけたものである。
【０１８６】
また、上記のカラープロファイルを介してＣＩＥＸＹＺ色空間上の所定の目標座標値（典型的には中間調に相当する座標値）に対応づけられた、その印刷機のＣＭＹＫの各色インクの色空間（ＣＭＹＫ色空間）上の座標値にさらに対応づけられた目標パッチデータ（ここでは、例えばＣ，Ｍ，Ｙ，Ｋとも網点面積率５０％等の中間調のパッチを表わすパッチデータ）であり、シアン（Ｃ）のインクとマゼンタ（Ｍ）のインクとイエロー（Ｙ）のインクとが重畳されたＣＭＹグレーパッチと墨（Ｋ）のインクのみのＫグレーパッチとを表わすパッチデータ）に基づくＣＭＹグレーパッチおよびＫグレーパッチを、印刷機が標準状態にあるときにインクキーの開度の設定値のみ標準状態から変化させることにより各色インクの塗布厚を変化させながら複数出力し、各ＣＭＹグレーパッチおよび各Ｋグレーパッチを測色してＣＩＥＸＹＺ色空間上の各座標値（各ＸＹＺ値）を求め、その求められたＣＩＥＸＹＺ色空間上の各座標値（各ＸＹＺ値）を上記のカラープロファイルに基づいてＣＭＹＫ色空間上の座標値（ＣＭＹＫ値）に変換する。
【０１８７】
このようにして得られたＣＭＹＫ色空間上の座標値と上記の設定値とをＣＭＹＫの各色インクごとに対応づける。図１７の記憶部９１０に記憶された対応関係９１０ｂは、上記のようにして得られたＣＭＹＫ色空間上の座標値と上記の設定値とのＣＭＹＫの各色インクごとかつ各インクキーごとの対応関係を表したものである。
【０１８８】
また、図１７のインク調整量指示装置９００を構成するＸＹＺ取得部９２０は、印刷機を用いて印刷用紙Ｐ上に印刷画像を出力するにあたりその印刷用紙Ｐ上に出力された、上記の目標パッチデータに基づくＣＭＹグレーパッチおよびＫグレーパッチ（ここでは、図６に示すグレーパッチＰ２（ＣＭＹグレーパッチＰ２１およびＫグレーパッチＰ２２）を測色計５００で測色することにより得られたＣＩＥＸＹＺ色空間上の座標値をその測色計５００から受け取る役割りを担っている。このＸＹＺ取得部７２０は、ハードウェア上は、主として図７に示す入力インタフェース５２６がその役割りを担っている。
【０１８９】
また、図１７のインク調整量指示装置９００の座標写像部９３０では、ＸＹＺ取得部９２０で受け取ったＣＩＥＸＹＺ色空間上の座標値（ＸＹＺ値）から、記憶部９１０に記憶されたカラープロファイル９１０ａに基づいて、ＣＭＹＫ色空間上の座標値が求められる。
【０１９０】
また、図１７のインク調整量指示装置９００の調整値算出部９４０では、記憶部９１０に記憶された対応関係９１０ｂ（ＣＭＹＫ色空間上の座標値とインク塗布厚調整のためのインクキー開度の調整値との対応関係）に基づいて、座標写像部９３０で求められたＣＭＹＫ色空間上の座標値を構成するＣＭＹＫの各値から各色インクごとかつ各インクキーごとの各調整値が求められる。
【０１９１】
さらに、図１７のインク調整量指示装置９１０を構成する調整値指示部９５０では、調整値算出部９４０で求められた調整値が指示される。
【０１９２】
本実施形態では、この調整値指示部９５０では、各色インクごとの各インクキーの調整値が図６に示すコンピュータ５１０の画像表示部５１０の表示画面上に表示されるとともに、それらの調整値が、各色インクに対応する調整値ごとに、各色インクごとのインクキー制御部（図６には一色分のインクキー制御部４１８が示されている）に送られて各インクキーの開度が自動的に調整され、これによって印刷用紙Ｐ上への各色インクの塗布厚が自動的に調整される。
【０１９３】
ただし、図１７のインク調整量指示装置９００の調整値指示部９５０ではそれらの調整値を表示画面上に表示することによってオペレータに向けて指示するにとどめ、インクキー制御部への各インクキーの開度の指令はオペレータに委ねてもよい。
【０１９４】
図１７のインク調整量指示装置９００の更なる詳細は、次に説明する本発明の第２実施形態のインク調整量指示方法を説明する中で説明する。
【０１９５】
図１８，図１９は、本発明の第２実施形態のインク調整量指示方法の処理の流れを示すブロック図およびフローチャートである。
【０１９６】
図１９のステップＳ５１，Ｓ５２は、前述の第１実施形態における図１１のステップＳ１１，Ｓ１２と同じである。すなわち、ここでは印刷機が標準状態に設定され、その標準状態にある印刷機でカラーチャートが印刷され測色されて画像データ上の値（ＣＭＹＫ色空間上の座標値）と印刷画像上の測色値（ＣＩＥＸＹＺ色空間上の座標値）との対応を表わすカラープロファイルが作成される。この作成されたカラープロファイルは、図６、図７に示すコンピュータ５７０に記憶される（図１７の記憶部９１０のカラープロファイル９１０ａ）。
【０１９７】
また、図１９のステップＳ６１では、印刷機が標準状態にあるときに、各インクキーの開度の設定値のみ標準状態から変化させながら、例えばＣＭＹＫのいずれについても網点面積率が５０％の所定の目標パッチデータに基づくＣＭＹグレーパッチおよびＫグレーパッチを各インクキーに対応して印刷し、それらのＣＭＹグレーパッチおよびＫグレーパッチを測色してＣＩＥＸＹＺ色空間上の各座標値（ＸＹＺ値）を求め、それらの各座標値（ＸＹＺ値）をステップＳ５２で作成したカラープロファイルに基づいてＣＭＹＫ色空間上の座標値に変換し、これにより各インクキーの開度の設定値とＣＭＹグレーパッチおよびＫグレーパッチのＣＭＹＫ色空間上の値（ＣＭＹＫ値）との対応関係を求める。
【０１９８】
このステップＳ６１で求められた対応関係も、図６、図７に示すコンピュータ５１０に記憶される（図１７の記憶部９１０の対応関係９１０ｂ）。
【０１９９】
尚、図６を参照して説明したように、インク塗布厚はインクキーの開度とロール回転速度との双方によって調整されるが、ここでは説明を単純化するため、ロールの回転速度は標準状態のままとし、インクキーの開度の調整のみによってインク塗布厚を調整するものとして説明している。
【０２００】
ただし、前述の第１実施形態で説明したようにして、ロール回転速度の調整と各インクキーの開度の調整との双方によりインク塗布厚を調整してもよい。
【０２０１】
本実施形態では以上の各ステップＳ５１，Ｓ５２，Ｓ６１が準備段階のステップであり、このような準備が終了した後、実際の画像印刷の場面に移る。
【０２０２】
印刷用紙Ｐ上に実際に画像を印刷する際には、図６に示すように、実際に必要な印刷画像Ｐ１のほか、印刷用紙Ｐの余白にステップＳ６１において対応関係を求める際に用いた目標パッチデータと同一の網点面積率（ここでは、上述したように、例えばＣＭＹＫの各色インクとも網点面積率５０％）の目標パッチデータに基づく中間調のグレーパッチＰ２（Ｃ，Ｍ，Ｙのインクが重畳されたＣＭＹグレーパッチＰ２１とＫインク単色のＫグレーパッチＰ２２）が印刷される。
【０２０３】
ここでは、ＣＭＹグレーパッチＰ２１とＫグレーパッチＰ２２は、図６に示されたように配列された複数のインクキー４１１ａ，４１１ｂ，…，４１１ｎにそれぞれに対応してそれぞれ１つずつ印刷される。これらのグレーパッチＰ２は、測色計５００の位置を通過するときにその測色計５００によって測色され、ＣＩＥＸＹＺ色空間上の座標値（ＸＹＺ値）が算出される（図１９ステップＳ７１ａ，Ｓ７１ｂ）。このＣＩＥＸＹＺ値は、図６に示すコンピュータ５１０に伝送されてそのコンピュータ５１０に取り込まれる（図１７のＸＹＺ取得部７２０）。
【０２０４】
すると、そのコンピュータ５１０では、図１７に示す記憶部９１０に記憶されたカラープロファイル９１０ａ（ステップＳ５２で作成されたカラープロファイル）が参照され、ＸＹＺ取得部７２０で得られたＣＩＥＸＹＺ値のうち、ＣＭＹグレーパッチを測色して得たＸＹＺ値からはＫ＝０％の拘束条件の下でデバイス信号（ＣＭＹ値）が算出され（ステップＳ７２）、Ｋグレーパッチを測色して得たＸＹＺ値からはＣ＝Ｍ＝Ｙ＝０％の拘束条件の下でデバイス信号（Ｋ値）が算出される（ステップＳ７２ｂ）。
【０２０５】
このデバイス信号ＣＭＹＫの算出の際は、測色計５００での測色により得られたＣＩＥＸＹＺ値からデバイス信号ＣＭＹＫを求めるだけでなく、それと同様にして、その測色計５００での測色の対象であるグレーパッチの目標となるＣＩＥＸＹＺ値も、その同じカラープロファイルに基づいてデバイス信号ＣＭＹＫ＿ｔａｒに変換される。
【０２０６】
尚、このデバイス信号ＣＭＹＫ＿ｔａｒは、グレーパッチを作成するために用いた目標パッチデータそのものであり、その目標パッチデータを記憶しておいたときは、目標ＣＩＥＸＹＺからＣＭＹＫ＿ｔａｒへの変換は不要である。
【０２０７】
次にステップＳ７３では、図１７のインク調整量指示装置９００の記憶部９１０に記憶された対応関係９１０ｂ（図１９のステップＳ６１で求められた対応関係（図１８（Ｂ）参照））に基づいて、上記のようにして求めたデバイス信号ＣＭＹＫとＣＭＹＫ＿ｔａｒからインクキーの調整値Ｍが算出される。このインクキーの調整値Ｍは、ＣＭＹＫの各インクのさらに各インクキーごとに求められる。
【０２０８】
このインクキーの調整値Ｍは、１色のインク（ここではシアン（Ｃ）とする）の１つのインクキーに関し、
Ｍｃ＝ｆ（Ｃ，Ｃ_std）……（１９）
と表現することができる。この（１９）式中、Ｍｃは、シアン（Ｃ）のインクのその１つのインクキーの調整値、Ｃは、ＣＭＹグレーパッチの測色値（ＸＹＺ値）からカラープロファイルに従って求めたＣＭＹＫ色空間上のＣの値、Ｃ_stdは、インクキーの開度の設定値を含めその印刷機の全てが標準状態にあるときの、シアン（Ｃ）のインクのそのインクキーに対するＣＭＹグレーパッチの測色値（ＸＹＺ値）からカラープロファイルに従って求めたＣＭＹＫ色空間上のＣの値である。
【０２０９】
図１９のステップＳ７４（図１７のインク調整量指示装置９００の調整値指示部９５０）では、ステップＳ７３（図１７のインク調整量指示装置９００の調整値算出部９４０）で求められた調整値Ｍがコンピュータ５１０の表示画面上に表示されるとともに（図１３参照）、ＣＭＹＫの各色インクに対応したインクキー制御部（図６には一色分のインクキー制御部４１８が示されている）に送られてＣＭＹＫの各色インクの各インクキーの開度が調整される。
【０２１０】
前述の第１実施形態の場合、べた濃度と設定値との対応関係を求めておき、中間調のグレーバッチの測色値からべた濃度の推定値を求め、その推定値からインク塗布厚の調整値を求めているため、印刷画像の特質に応じて任意に調整された網点面積率のグレーパッチをその印刷画像とともに印刷して、そのグレーパッチの、中間調の網点面積率のインク塗布厚を調整することができるが、ここで説明している第２実施形態の場合、図１９のステップＳ６１での対応関係を求めるために印刷するグレーパッチと、実際の画像印刷時に余白に印刷するグレーパッチは同じ網点面積率のパッチデータに基づくグレーパッチである必要があり、したがって印刷画像の特質に応じて異なる中間調のインク塗布厚を調整しようとする場合、各中間調ごとに対応関係を求めておく必要がある。ただし、それと引き換えに、図１８、図１９からも分かるように、実際の印刷中のインク塗布厚の調整のための演算は前述の第１実施形態の場合よりも単純である。
【０２１１】
次に、図１６〜図１９を参照して説明してきた第２実施形態の変形例について説明する。
【０２１２】
図２０〜図２３は、本発明の第２実施形態の変形例における、それぞれ、ＣＤＲＯＭに記憶されたインク調整指示プログラムの模式構成図、インク調整器指示装置の機能ブロック図、インク調整量指示方法の処理の流れを示すブロック図、およびインク調整量指示方法の処理の流れを示すフローチャートである。
【０２１３】
図２０のＣＤ−ＲＯＭ５７０に格納されたインク調整量指示プログラム８００は、この図２０上では図１６と同一である。図１６のインク調整量指示プログラムとの相違点については、図２１のインク調整量指示装置の説明と合わせて説明する。尚、図２０のインク調整量指示プログラム８００と図２１のインク調整量指示装置９００の関係は、図１６のインク調整量指示プログラムと図１７のインク調整量指示装置の関係と同一である。すなわち、図２１に示すインク調整量指示装置９００は、図６，図７に示すコンピュータ５１０に図２０に示すインク調整量指示プログラム８００がインストールされて実行されることによりそのコンピュータ５１０内に構築されるものである。
【０２１４】
図２１に示すインク調整量指示装置９００を構成する記憶部９１０には、図１７に示すインク調整量指示装置を構成する記憶部と比べ、さらに写像関係９１０ｃが記憶されている点が異なっている。この写像関係９１０ｃは、ＣＭＹＫ色空間上の、画像データに対応づけられる座標値からドットゲインを含んだ座標値への写像関係を規定したものであり、図９に示すインク調整量指示装置７００の記憶部７１０に記憶されている写像関係７１０ｂと同様にして作成されたものである。
【０２１５】
また、図２１に示すインク調整量指示装置９００の記憶部９１０に記憶された対応関係９１０ｂは、ドットゲインを考慮したときのＣＭＹＫの各座標値と、各インクキーの開度の設定値との対応関係を規定したものである。
【０２１６】
また、これに伴い、図２１に示すインク調整量指示装置９３０の座標写像部９３０では、ＸＹＺ取得部で得られたＣＩＥＸＹＺ値がカラープロファイル９１０ａに基づいてＣＭＹＫ値に変換され（ここまでは、図１７のインク調整量指示装置の座標写像部と同様）、さらに、そのＣＭＹＫ値が、写像関係９１０ｃに基づいて、ドットゲインを考慮したときの新たなＣＭＹＫ値へと変換される。
【０２１７】
さらに、これに伴い、調整値算出部９４０では、ドットゲインを考慮したときのＣＭＹＫの各座標値とインクキー設定値との対応関係９１０ｂに基づいて、座標写像部９３０で求められた、ドットゲインを考慮したときの新たなＣＭＹＫ値からインクキーの調整値が求められる。
【０２１８】
この図２１のインク調整量指示装置の、図１７のインク調整量指示装置との相違点は、以上の点のみであり、その他は全て図１７のインク調整量指示装置と同様である。
【０２１９】
図２２，図２３を参照して、これらの相違点についてさらに説明する。
【０２２０】
図２２を図１８と比べると、図２２（Ｃ）の写像関係が追加されており、かつ、ＣＭＹＫから、その写像関係に基づくドットゲインを含んだときのＣＭＹＫであるＣ′Ｍ′Ｙ′Ｋ′への変換のブロックが追加されている。また、図２２（Ｂ）に示す対応関係は、図１８に示すようなＣＭＹＫとインクキーの設定値との対応関係ではなく、ドットゲインを考慮した後のＣ′Ｍ′Ｙ′Ｋ′とインクキーの設定値との対応関係であり、その対応関係に基づいて、図２２（Ｃ）の写像関係に基づいてドットゲインが考慮されたＣ′Ｍ′Ｙ′Ｋ′からインクキーの調整値Ｍが求められる。
【０２２１】
図２３では、図１９と比べ、ステップＳ８１，Ｓ８２ａ，Ｓ８２ｂが追加されている。また、図２３のステップＳ６１，Ｓ７３は、図１９のステップＳ６１，Ｓ７３とは若干異なる。
【０２２２】
ステップＳ８１では、ドットゲイン算入前後の写像関係が求められる。このステップＳ８１における写像関係の求め方は、図１１のステップＳ３１における写像関係の求め方と同一であり、ここでは重複説明は省略する。
【０２２３】
また、図２３のステップＳ６１では、印刷機が標準状態にあるときに、各インクキーの開度の設定値のみ標準状態から変化させながら、例えばＣＭＹＫのいずれについても網点面積率が５０％の所定の目標パッチデータに基づくＣＭＹグレーパッチおよびＫグレーパッチを各インクキーに対応して印刷し、それらのＣＭＹグレーパッチおよびＫグレーパッチを測色してＣＩＥＸＹＺ色空間上の各座標値（ＸＹＺ値）を求め、それらの各座標値（ＸＹＺ値）をステップＳ５２で作成したカラープロファイルに基づいてＣＭＹＫ色空間上の座標値に変換する。
【０２２４】
ここまでの処理は、前述した図１９のステップＳ６１の処理と同一である。図２３のステップＳ６１では、さらにその後、ステップＳ８１で求められた写像関係に基づいて、カラープロファイルに基づく変換により得られたＣＭＹＫ色空間上の座標値から、ドットゲインを考慮したときの、ＣＭＹＫ色空間上の新たな座標値に変換し、これにより、インクキーの設定値と、ＣＭＹグレーパッチおよびＫグレーパッチのＣＭＹＫ色空間上のドッゲインを考慮した座標値（Ｃ′Ｍ′Ｙ′Ｋ′値）との対応関係を求める。
【０２２５】
この対応関係は、例えばシアン（Ｃ）の１つのインクキーに関し、
Ｍ_C＝ｆ（Ｃ′，Ｃ′_std） …（２０）
と表現することができる。ここでＭ_Cは、シアン（Ｃ）のインクのその１つのインクキーの調整量、Ｃ′はＣＭＹグレーパッチの測色値（ＸＹＺ値）からカラープロファイルおよび写像関係に従って求めたＣＭＹＫ色空間上のＣの値、Ｃ′_stdは、インクキーの開度の設定値を含めその印刷機の全てが標準状態にあるときの、シアン（Ｃ）のインクのそのインクキーに対するＣＭＹグレーパッチの測色値（ＸＹＺ値）からカラープロファイルおよび写像関係に従って求めたＣＭＹＫ色空間上のＣの値である。
【０２２６】
また、図２３のステップＳ８２ａ，Ｓ８２ｂでは、ステップＳ７２ａ，Ｓ７２ｂでカラープロファイルに従って求めたＣＭＹＫ値を、ステップＳ８１で求めた写像関係に基づいてドットゲインを考慮したＣ′Ｍ′Ｙ′Ｋ′値に変換される。
【０２２７】
ステップＳ７３では、ステップＳ６１で求めた。インクキーの設定値とグレーパッチのドットゲインを考慮したときのデバイス信号Ｃ′Ｍ′Ｙ′Ｋ′との対応関係が参照されて、ステップＳ８２ａ，Ｓ８２ｂで求めたデバイス信号Ｃ′Ｍ′Ｙ′Ｋ′からインクキーの調整値Ｍが算出される。
【０２２８】
尚、以上の各実施形態は、本発明にいう画像出力デバイスの一例として印刷機を取り上げて説明したが、本発明の対象となる画像出力デバイスは、印刷機に限られるものではなく、本発明は、網点面積率により濃度階調や色調を表現する網点画像を出力する画像出力デバイスであって、インク塗布厚を調整する機構のある画像出力デバイス一般を対象とすることができる。
【０２２９】
【発明の効果】
以上説明したように、本発明によれば、オペレータの熟練に頼ることなくインク調整量が客観的に算出される。
【図面の簡単な説明】
【図１】本発明の一実施形態が適用された印刷システムを含む、印刷およびプルーフ画像作成システムの全体構成図である。
【図２】印刷プロファイルの概念図である。
【図３】プリンタプロファイルの概念図である。
【図４】印刷プロファイルとプリンタプロファイルを結合させたリンクプロファイルを示す図である。
【図５】印刷機の一部を示す模式図である。
【図６】印刷機のうちの、本発明の実施形態に関係する部分、および本発明の一実施形態としてのインク調整量指示装置として動作するコンピュータの模式図である。
【図７】図６に外観を示すコンピュータのハードウェア構成図である。
【図８】ＣＤ−ＲＯＭに記憶されたインク調整量指示プログラムの模式構成図である。
【図９】本発明のインク調整量指示装置の一実施形態を示す機能ブロック図である。
【図１０】本発明の一実施形態のインク調整量指示方法の処理の流れを示すブロック図である。
【図１１】本発明の一実施形態のインク調整量指示方法の処理の流れを示すフローチャートである。
【図１２】べた濃度とインクキーの開度の設定値との対応関係を示す図である。
【図１３】図６，図７に示すコンピュータ５１０の表示画面５３０ａ上に表示されるインクキー開度調整値Ｍを示す図である。
【図１４】べた濃度とロール回転速度設定値との一色分の対応関係値を示す概念図である。
【図１５】ロール回転速度調整値の表示例を示す図である。
【図１６】ＣＤ−ＲＯＭに記憶された本発明の第２実施形態としてのインク調整量指示プログラムの模式構成図である。
【図１７】本発明の第２実施形態としてのインク調整量指示装置を示す機能ブロック図である。
【図１８】本発明の第２実施形態のインク調整量指示方法の処理の流れを示すブロック図である。
【図１９】本発明の第２実施形態のインク調整量指示方法の処理の流れを示すフローチャートである。
【図２０】本発明の第２実施形態の変形例における、ＣＤＲＯＭに記憶されたインク調整指示プログラムの模式構成図である。
【図２１】本発明の第２実施形態の変形例における、インク調整器指示装置の機能ブロック図である。
【図２２】本発明の第２実施形態の変形例における、インク調整量指示方法の処理の流れを示すブロック図である。
【図２３】本発明の第２実施形態の変形例における、インク調整量指示方法の処理の流れを示すフローチャートである。
【符号の説明】
１０ カラースキャナ
１１ 原稿画像
２０ ワークステーション
３０ フィルムプリンタ
４０ 印刷システム
４１ 印刷画像
５０ パーソナルコンピュータ
６０ プリンタ
６１ プルーフ画像
７０ 測色計
４１１，４１１ａ，４１１ｂ，…，４１１ｎ インクキー
４１２ ロール
４１６ インク供給部
４１７ ロール回転制御
４１８ インクキー制御部
５００ 測色計
５１０ コンピュータ
５２０ 本体装置
５２１ ＣＰＵ
５２２ 主メモリ
５２３ ハードディスク装置
５２４ ＦＤドライブ
５２５ ＣＤ−ＲＯＭドライブ
５２６ 入力インターフェイス
５２７ 出力インターフェイス
５２８ バス
５４０ キーボード
５５０ マウス
５６０ ＦＤ
５７０ ＣＤ−ＲＯＭ
６００ インク調整量指示プログラム
６１０ 記憶部
６２０ ＸＹＺ取得部
６３０ べた濃度算出部
６３１ ドットゲイン算入部
６３２ 濃度推定部
６４０ 調整値算出部
６５０ 調整値指示部
７００ インク調整量指示プログラム
７１０ 記憶部
７２０ ＸＹＺ取得部
７３０ べた濃度算出部
７３１ ドットゲイン算入部
７３２ べた濃度推定部
７４０ 調整値算出部
７５０ 調整値指示部
８００ インク調整量指示プログラム
８１０ 記憶部
８２０ ＸＹＺ取得部
８３０ 座標写像部
８４０ 調整値算出部
８５０ 調整値指示部
９００ インク調整量指示装置
９１０ 記憶部
９２０ ＸＹＺ取得部
９３０ 調整量指示装置
９４０ 調整値算出部
９５０ 調整値指示部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink adjustment amount instruction method, an ink adjustment amount instruction device, a computer, and the like for instructing an adjustment amount of an ink application thickness when outputting a halftone image using an image output device that outputs a halftone image The present invention relates to an ink adjustment apparatus instruction program that causes an information processing apparatus to operate as an ink adjustment amount instruction apparatus.
[0002]
[Prior art]
In a printing machine that rotates a rotary press and performs a large amount of printing, and some other printers, a halftone image in which density and color are expressed by the ratio of the ink application area (halftone dot area ratio) is output.
[0003]
However, even in the case of a halftone image, the density or the like is not necessarily determined only by the halftone dot area ratio, and the density or the like varies depending on the thickness of the ink in the portion where the ink is applied.
[0004]
Therefore, for example, in the case of a printing press, a plurality of (for example, 30) ink keys adjacent to a roll on the upstream side of the ink supply path for supplying ink to the printing plate and arranged in the rotation axis direction of the roll are provided. The thickness of the ink supplied to the printing plate is always adjusted to a predetermined ink thickness by adjusting the opening degree of the ink keys or adjusting the rotation speed of the roller. When the opening degree of each of the plurality of ink keys is adjusted, the ink application thickness is adjusted for each region obtained by dividing the rotation axis direction of the roller according to the plurality of ink keys, and when the rotation speed of the roller is adjusted, the printing plate The ink application thickness over the entire area is adjusted.
[0005]
Here, in order to adjust the ink application opening by adjusting the opening of the ink key and the roller rotation speed, color patches arranged in the direction of the rotation axis of the roller are printed in the margin area on the printing paper. Is measured online, and the result of the measurement is shown to the operator. The operator adjusts the opening degree of the ink key and the rotation speed of the roller by looking at the measurement result.
[0006]
Conventionally, as described above, although the on-line measurement result is shown to the operator, for example, when the measurement result is a little “reddish”, should the ink thickness of C (cyan) be reduced? It is not always clear that the ink thicknesses of M (magenta) and Y (yellow) should be increased, and the adjustment is performed depending on the experience and intuition of the operator.
[0007]
Here, Patent Document 1 discloses a technique in which an ink supply amount supply device is provided with a target input interruption so that the opening degree of an arbitrary ink key can be adjusted during ink supply amount control. The background behind this technology is as follows. The ink supply amount adjusting device as disclosed in Patent Document 1 is generally a solid density value registered in a control target value input device and a solid density value measured by a device that measures the ink density of printed matter. Based on the above, it has a function to correct the ink supply. However, even if this solid density is controlled to be the target value, there are various types of paper such as art paper, matte paper, etc. Etc.) The dot gain amount changes due to factors such as changes in the temperature / humidity of the room where the printing press is placed, and the color similar to the color proof sample is not finished. Therefore, as described in paragraph numbers [0005] to [0008] of Patent Document 1, it is necessary for the operator to perform an operation of resetting the target value. With respect to such a work, this patent document 1 allows the operator to perform the target value correction interruption process while observing the state of the halftone color that is regarded as important by the operator. It is what improves efficiency. However, in this Patent Document 1, there is no change in this point in that the operator's experience and trial and error are still necessary in the operation of changing the target value, and this point is not solved at all.
[0008]
[Patent Document 1]
JP-A-9-300590
[0009]
[Problems to be solved by the invention]
In view of the above circumstances, the present invention provides an ink adjustment amount instruction method, an ink adjustment amount instruction device, and an information processing apparatus such as a computer that objectively calculate and instruct an ink adjustment amount without relying on operator skill. An object of the present invention is to provide an ink adjustment amount instruction program that operates as such an ink adjustment amount instruction device.
[0010]
[Means for Solving the Problems]
The first ink adjustment amount instruction method of the ink of the present invention that achieves the above object is to apply a plurality of color inks onto a predetermined recording medium while adjusting the application thickness of each color ink. In an ink adjustment amount instruction method for instructing each adjustment amount for adjusting the coating thickness of each color ink when outputting a halftone image on a recording medium using an image output device that outputs a halftone image to
Output by the image output device based on the coordinate value in the device color space with the dot area ratio of each color ink as the coordinate axis and the image data associated with the coordinate value when the image output device is in a predetermined standard state A first step of obtaining a color profile in which coordinate values on a predetermined common color space representing colors on a halftone dot image are associated with each other;
By changing each single-color solid patch based on each single-color patch data associated with a dot area ratio of 100% for each color ink from the standard state only when the image output device is in a predetermined standard state. Multiple output for each ink while changing the coating thickness of each color ink, measure the solid density of each single color solid patch, and find the correspondence between the solid density value of each single color solid patch and the above adjustment amount for each color ink The second step;
When outputting a halftone image on a recording medium using an image output device, on a device color space that is output on the recording medium and associated with a predetermined target coordinate value on a common color space via a color profile A third step of obtaining a coordinate value in the common color space by measuring a target color patch based on the target patch data further associated with the coordinate value of
A fourth step for obtaining, for each color ink, an estimated value of solid density in the current state of the image output device based on both the coordinate value obtained in the third step and the target coordinate value on the common color space; ,
A fifth step for obtaining each adjustment amount for each color ink from the estimated value of the solid density for each color ink obtained in the fourth step based on the correspondence obtained in the second step;
And a sixth step for instructing each adjustment amount obtained in the fifth step.
[0011]
Here, the third step is preferably a step of outputting a gray patch as the target color patch.
[0012]
In the first ink adjustment amount instruction method, the sixth step instructs each adjustment amount obtained in the fifth step to an operator who manually adjusts the coating thickness of each color ink of the image output device. Alternatively, the sixth step instructs each adjustment amount obtained in the fifth step to a coating thickness adjusting device that automatically adjusts the coating thickness of each color ink of the image output device. It may be.
[0013]
Conventionally, in order to output an image having a desired density and color with an image output device, a color profile of the image output device is created, and the image data edited for image output is used as the color profile of the image output device. The converted image data is sent to an image output device, and the image output device outputs an image of a desired color based on the converted image data.
[0014]
The present invention has been conceived and completed by calculating the adjustment amount of the ink coating thickness using this color profile.
[0015]
When a halftone dot image is output on paper, the dot area ratio of the halftone dot image on the paper becomes a larger area ratio than the halftone dot area ratio on the image data due to the spread of ink or the like. . The first ink adjustment amount instruction method according to the present invention accurately calculates the ink adjustment amount in consideration of the dot gain. On the other hand, in the second ink adjustment amount instruction method of the present invention, which will be described later, by creating a color patch having the same dot area ratio as the dot area ratio at the time of initial data collection, the influence of the dot gain is made positive. Therefore, an accurate ink adjustment amount is calculated.
[0016]
Here, in the first ink adjustment amount instruction method, the dot gain on the device color space is calculated from the coordinate value associated with the image data on the device color space as a specific method considering the dot gain. The mapping relationship to the included coordinate values is determined, and the fourth step obtains the coordinate values in the device color space based on the color profile from the coordinate values in the common color space obtained in the third step. On the device color space obtained based on the color profile from the coordinate value on the device color space associated with the target coordinate value on the color space and the coordinate value on the common color space obtained in the third step. A first sub-step for converting both of the coordinate values into each new coordinate value on the device color space based on the mapping relationship, and the device color space obtained in the first sub-step Based on the two new coordinate values above may be configured to have a second sub-step of obtaining an estimate of the solid density in the current state of the image output device.
[0017]
In this case, the mapping relationship is calculated by calculating a halftone value for each color ink including dot gain based on the coordinate value in the common color space associated with the coordinate value in the device color space by the color profile. The mapping relationship may be determined by performing a plurality of coordinate values in the device color space, or the mapping relationship is based on a plurality of patch data associated with a plurality of coordinate values in the device color space. More preferably, it is determined by outputting a plurality of color patches and measuring the halftone percentage of each color ink including dot gain for each of the plurality of color patches. In these cases, the plurality of coordinate values are preferably coordinate values corresponding to gray colors having different densities.
[0018]
The second sub-step includes two density values corresponding to the two new coordinate values based on each of the two new coordinate values and a standard solid density value when the image output device is in a standard state. And an estimated value of the solid density in the current state of the image output device may be obtained based on the two density values and the standard solid density value.
[0019]
The second ink adjustment amount instruction method of the ink adjustment amount instruction method of the present invention that achieves the above object is to apply a plurality of color inks on a predetermined recording medium while adjusting the application thickness of each color ink. Instructing each adjustment amount for adjusting the coating thickness of each color ink when outputting a halftone image on the recording medium using an image output device that outputs the halftone image on the recording medium In the ink adjustment amount instruction method,
Based on the coordinate value in the device color space with the dot area ratio of each color ink as the coordinate axis, and the image output device based on the image data associated with the coordinate value when the image output device is in a predetermined standard state, A first step of obtaining a color profile representing a color on an output halftone image and corresponding to a coordinate value on a predetermined common color space;
A target color patch based on target patch data further associated with a coordinate value on a device color space that is associated with a predetermined target coordinate value on a common color space via a color profile is output by the image output device to a predetermined standard. By changing only the adjustment amount above from the standard state when it is in a state, the output thickness of each color ink is changed and multiple outputs are output, and the target color patch is measured to determine the coordinate value in the common color space. Converting a coordinate value on the common color space into a coordinate value on the device color space, and obtaining a correspondence between the coordinate value on the device color space and the adjustment amount for each color ink;
Third step of obtaining a coordinate value in a common color space by measuring a target color patch based on the target patch data output on the recording medium when outputting a halftone image on the recording medium using the image output device When,
A fourth step of obtaining a coordinate value on the device color space from the coordinate value on the common color space obtained in the third step;
Based on the correspondence obtained in the second step, the fifth adjustment amount for each color ink is obtained from the value for each color ink constituting the coordinate value in the device color space obtained in the fourth step. Steps,
And a sixth step for instructing each adjustment amount obtained in the fifth step.
[0020]
Here, in the second ink adjustment amount instruction method, it is preferable that the second step and the third step are steps of outputting a gray patch as the target color patch.
[0021]
Also in the second ink adjustment amount instruction method, as in the first ink adjustment instruction method, the sixth step uses the adjustment amounts obtained in the fifth step for the respective color inks of the image output device. The operator may instruct the operator to manually adjust the coating thickness, or the sixth step may automatically adjust the adjustment thickness obtained in the fifth step and the coating thickness of each color ink of the image output device. You may instruct | indicate toward the coating thickness adjustment apparatus.
[0022]
In the second ink adjustment amount instruction method,
In the second step, the coordinate value in the common color space obtained by measuring the target color patch is converted into the coordinate value in the device color space based on the color profile, and the coordinate value in the device color space It is a step to obtain the correspondence with the adjustment amount,
The fourth step may be a step of obtaining a coordinate value on the device color space based on a color profile from the coordinate value on the common color space obtained in the third step, or
On the device color space, a mapping relationship from a coordinate value associated with image data to a coordinate value including dot gain is determined,
The second step converts the coordinate value in the common color space obtained by measuring the target color patch into the coordinate value in the device color space based on the color profile, and converts the coordinate value in the device color space to the mapping Converting to a new coordinate value on the device color space based on the relationship, and obtaining a correspondence relationship between the new coordinate value and each of the adjustment amounts,
In the fourth step, the coordinate value in the device color space is obtained based on the color profile from the coordinate value in the common color space obtained in the third step, and the coordinate value in the device color space is obtained based on the mapping relationship. A step of obtaining a new coordinate value in the device color space,
The fifth step may be a step of obtaining each adjustment amount for each color ink from the value for each color ink constituting the new coordinate value of the device color space obtained in the fourth step.
[0023]
The first ink adjustment amount indicating device of the ink adjustment amount indicating device of the present invention that achieves the above object applies a plurality of color inks on a predetermined recording medium while adjusting the application thickness of each color ink. Instructing each adjustment amount for adjusting the coating thickness of each color ink when outputting a halftone image on the recording medium using an image output device that outputs the halftone image on the recording medium In the ink adjustment amount instruction method,
Based on the coordinate value in the device color space with the dot area ratio of each color ink as the coordinate axis, and the image output device based on the image data associated with the coordinate value when the image output device is in a predetermined standard state, A color profile in which coordinate values in a predetermined common color space representing colors on the output halftone dot image are associated with each other, and each color ink based on each single color patch data associated with a halftone dot area ratio of 100%. Multiple single color solid patches are output for each color ink while changing the coating thickness of each color ink by changing only the adjustment amounts from the standard state when the image output device is in a predetermined standard state. The correspondence between the solid density value of each single-color solid patch obtained by measuring the solid density and the adjustment amount for each color ink is described. A storage unit to keep,
When outputting a halftone image on a recording medium using an image output device, on a device color space that is output on the recording medium and associated with a predetermined target coordinate value on a common color space via a color profile A colorimetric data acquisition unit that acquires coordinate values on a common color space obtained by measuring a target color patch based on the target patch data further associated with the coordinate value of
A density obtained by obtaining an estimated value of the solid density in the current state of the image output device for each color ink based on both the coordinate value acquired by the colorimetric data acquisition unit and the target coordinate value on a common color space. A calculation unit;
An adjustment amount calculation unit for obtaining each adjustment amount for each color ink from the estimated value of the solid density for each color ink obtained by the solid density calculation unit based on the correspondence relationship stored in the storage unit;
And an adjustment amount instruction unit for instructing each adjustment amount obtained by the adjustment amount calculation unit.
[0024]
The first ink adjustment amount instruction device is associated with the first ink adjustment amount instruction method described above, and is suitably applied to the implementation of the first ink adjustment amount instruction method.
[0025]
Here, in the first ink adjustment amount instruction device, the adjustment amount instruction unit directs each adjustment amount obtained by the adjustment amount calculation unit to an operator who manually adjusts the coating thickness of each color ink of the image output device. The adjustment amount instruction unit may direct each adjustment amount obtained by the adjustment amount calculation unit to an application thickness adjustment device that automatically adjusts the application thickness of each color ink of the image output device. May be used.
[0026]
In the first ink adjustment amount indicating device, the storage unit further changes the coordinate value associated with the image data on the device color space to the coordinate value including the dot gain on the device color space. To remember the mapping relationship of
The solid density calculation unit obtains coordinate values in the device color space based on the color profile from the coordinate values in the common color space acquired by the colorimetric data acquisition unit, and associates them with the target coordinate values in the common color space. Both the coordinate value in the obtained device color space and the coordinate value in the device color space obtained based on the color profile from the coordinate value in the common color space acquired by the colorimetric data acquisition unit. Based on the relationship, a dot gain calculation unit that converts each new coordinate value on the device color space and an image output device based on the two new coordinate values on the device color space obtained by the dot gain calculation unit It is good also as a structure provided with the solid density | concentration estimation part which calculates | requires the solid density | concentration estimated value in the present state. In this case, the solid density estimation unit is configured to generate two values corresponding to the two new coordinate values based on each of the two new coordinate values and the standard solid density value when the image output device is in the standard state. A density value may be obtained, and an estimated value of the solid density in the current state of the image output device may be obtained based on the two density values and the standard solid density value.
[0027]
The second ink adjustment amount indicating device of the ink adjustment amount indicating device of the present invention that achieves the above object applies a plurality of color inks onto a predetermined recording medium while adjusting the application thickness of each color ink. Instructing each adjustment amount for adjusting the coating thickness of each color ink when outputting a halftone image on the recording medium using an image output device that outputs the halftone image on the recording medium In the ink adjustment amount indicating device,
Based on the coordinate value in the device color space with the dot area ratio of each color ink as the coordinate axis, and the image output device based on the image data associated with the coordinate value when the image output device is in a predetermined standard state, A color profile that associates a coordinate value on a predetermined common color space representing a color on the output halftone image, and is associated with a predetermined target coordinate value on the common color space via the color profile The target color patch based on the target patch data further associated with the coordinate values in the device color space is changed from the standard state only for the adjustment amounts when the image output device is in the predetermined standard state. Multiple output for each color ink while changing the coating thickness, color measurement of the target color patch to obtain the coordinate value on the common color space, common color space Obtained by converting the coordinate values to coordinate values on a device color space, a storage unit for storing a correspondence between each color ink of the coordinate value and the adjustment amount on the device color space,
When outputting a halftone image on a recording medium using an image output device, the coordinate value in the common color space obtained by measuring the target color patch based on the target patch data output on the recording medium is obtained. A colorimetric data acquisition unit to acquire;
A coordinate mapping unit for obtaining a coordinate value on the device color space from the coordinate value on the common color space acquired by the colorimetric data acquisition unit;
An adjustment amount calculation unit for obtaining each adjustment amount for each color ink from the values for each color ink constituting the coordinate values in the device color space obtained by the coordinate mapping unit based on the correspondence relationship stored in the storage unit; ,
And an adjustment amount instruction unit for indicating each adjustment amount obtained by the adjustment amount calculation unit.
[0028]
This second ink adjustment amount indicating device can be suitably used for implementing the above-described second ink adjustment amount indicating method.
[0029]
Here, also in the second ink adjustment amount instruction device, as in the case of the first ink adjustment amount instruction device described above, the adjustment amount instruction unit determines each adjustment amount obtained by the adjustment amount calculation unit. It may be directed to an operator who manually adjusts the coating thickness of each color ink of the image output device, or the adjustment amount instruction unit determines the adjustment amount obtained by the adjustment amount calculation unit as the image output device. It may be directed to a coating thickness adjusting device that automatically adjusts the coating thickness of each color ink.
[0030]
In addition, the first ink adjustment amount instruction program of the ink adjustment amount instruction program of the present invention is executed in the information processing apparatus that executes the program, and the information processing apparatus is used as the first ink adjustment amount instruction program of the present invention. It operates as a device. That is, the first ink adjustment amount instruction program of the present invention is
The information processing apparatus is executed in an information processing apparatus that executes a program, and the information processing apparatus applies halftone dots on the recording medium by applying a plurality of color inks on a predetermined recording medium while adjusting the coating thickness of each color ink. Ink adjustment amount that operates as an ink adjustment amount indicating device that indicates each adjustment amount for adjusting the coating thickness of each color ink when a halftone image is output on a recording medium using an image output device that outputs an image An instruction program,
The information processing apparatus is
Based on the coordinate value in the device color space with the dot area ratio of each color ink as the coordinate axis, and the image output device based on the image data associated with the coordinate value when the image output device is in a predetermined standard state, A color profile in which coordinate values in a predetermined common color space representing colors on the output halftone dot image are associated with each other, and each color ink based on each single color patch data associated with a halftone dot area ratio of 100%. Multiple single color solid patches are output for each color ink while changing the coating thickness of each color ink by changing only the adjustment amounts from the standard state when the image output device is in a predetermined standard state. The correspondence between the solid density value of each single-color solid patch obtained by measuring the solid density and the adjustment amount for each color ink is described. A storage unit to keep,
When outputting a halftone image on a recording medium using an image output device, the device color space associated with a predetermined target coordinate value on the common color space via the color profile output on the recording medium is used. A colorimetric data acquisition unit that acquires coordinate values on a common color space obtained by measuring the target color patch based on the target patch data further associated with the coordinate value;
A density obtained by obtaining an estimated value of the solid density in the current state of the image output device for each color ink based on both the coordinate value acquired by the colorimetric data acquisition unit and the target coordinate value on a common color space. A calculation unit;
An adjustment amount calculation unit for obtaining each adjustment amount for each color ink from the estimated value of the solid density for each color ink obtained by the solid density calculation unit based on the correspondence relationship stored in the storage unit;
It is operated as an ink adjustment amount instruction device including an adjustment amount instruction unit for instructing each adjustment amount obtained by the adjustment amount calculation unit.
[0031]
Here, in the first ink adjustment amount instruction program, the adjustment amount instruction unit directs each adjustment amount obtained by the adjustment amount calculation unit to an operator who manually adjusts the coating thickness of each color ink of the image output device. Alternatively, the adjustment amount instruction unit may apply each adjustment amount obtained by the adjustment amount calculation unit to an application thickness adjustment device that manually adjusts the application thickness of each color ink of the image output device. It may be directed to.
[0032]
In the first ink adjustment amount instruction program,
The storage unit further stores a mapping relationship from the coordinate value associated with the image data on the device color space to the coordinate value including the dot gain on the device color space,
The solid density calculation unit obtains coordinate values in the device color space based on the color profile from the coordinate values in the common color space acquired by the colorimetric data acquisition unit, and associates them with the target coordinate values in the common color space. Both the coordinate value in the obtained device color space and the coordinate value in the device color space obtained based on the color profile from the coordinate value in the common color space acquired by the colorimetric data acquisition unit. Based on the relationship, a dot gain calculation unit that converts each new coordinate value on the device color space and an image output device based on the two new coordinate values on the device color space obtained by the dot gain calculation unit A solid concentration estimation unit for obtaining an estimated value of the solid concentration in the current state of the current state. In this case, the solid concentration estimation unit includes the two new coordinate values, respectively. Two density values corresponding to the two new coordinate values are obtained based on the standard solid density value when the image output device is in the standard state, and based on the two density values and the standard solid density value. Alternatively, an estimated value of the solid density in the current state of the image output device may be obtained.
[0033]
The second ink adjustment amount instruction program of the ink adjustment amount instruction program of the present invention is executed in the information processing apparatus that executes the program, and the information processing apparatus is used as the second ink adjustment amount instruction program of the present invention. It operates as a device. That is, the second ink adjustment amount instruction program of the present invention is:
The information processing apparatus is executed in an information processing apparatus that executes a program, and the information processing apparatus applies halftone dots on the recording medium by applying a plurality of color inks on a predetermined recording medium while adjusting the coating thickness of each color ink. Ink adjustment amount instruction that operates as an ink adjustment amount instruction device that indicates each adjustment amount for adjusting the coating thickness of each color ink when outputting a halftone image on the recording medium using an image output device that outputs an image In the program
Based on the coordinate value in the device color space with the dot area ratio of each color ink as the coordinate axis, and the image output device based on the image data associated with the coordinate value when the image output device is in a predetermined standard state, A color profile that associates a coordinate value on a predetermined common color space representing a color on the output halftone image, and is associated with a predetermined target coordinate value on the common color space via the color profile Each color ink is obtained by changing the target color patch based on the target patch data further associated with the coordinate value on the device color space from the standard state only for the adjustment amounts when the image output device is in the predetermined standard state. Output multiple colors for each color ink while changing the coating thickness of the ink, measure the color of those target color patches, find the coordinate value in the common color space, Obtained by converting the coordinate values of the upper to the coordinate values on a device color space, a storage unit for storing a correspondence between each color ink of the coordinate value and the adjustment amount on the device color space,
When outputting a halftone image on a recording medium using an image output device, the coordinate value in the common color space obtained by measuring the target color patch based on the target patch data output on the recording medium is obtained. A colorimetric data acquisition unit to acquire;
A coordinate mapping unit for obtaining a coordinate value on the device color space from the coordinate value on the common color space acquired by the colorimetric data acquisition unit;
An adjustment amount calculation unit for obtaining each adjustment amount for each color ink from the values for each color ink constituting the coordinate values in the device color space obtained by the coordinate mapping unit based on the correspondence relationship stored in the storage unit; ,
An ink adjustment amount instruction device is provided that includes an adjustment amount instruction unit that instructs each adjustment amount obtained by the adjustment amount calculation unit.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0035]
FIG. 1 is an overall configuration diagram of a printing and proof image creation system including a printing system to which an embodiment of the present invention is applied. Here, the printing system 40 in FIG. 1 includes an ink adjustment amount instruction device and the like according to an embodiment of the present invention in addition to a printing machine. Therefore, the feature of the embodiment of the present invention is not in the entire printing and proof image system shown in FIG. 1 but in the internal configuration of the printing system 40 shown in one block of them. In order to describe a conventional method of use, an overview of the entire printing and proof image creation system shown in FIG. 1 will be described.
[0036]
In the color scanner 10, the original image 11 is read, and four color separations including cyan (C), magenta (M), yellow (Y), and black (K) representing the read original image 11 are displayed. Image data is generated. The CMYK image data is input to the workstation 20. In the workstation 20, plate collection based on the input image data is performed by the operator, and image data representing an image for printing is generated. The image data for printing is input to the film printer 30 when printing is performed, and the film printer 30 creates the CMYK plate originals for printing corresponding to the input image data.
[0037]
A printing plate is created from the printing film original plate, and the created printing plate is mounted on a printing machine constituting the printing system 40. Ink is applied to the printing plate mounted on the printing press, and the applied ink is transferred onto a printing sheet to form a printed image 41 on the sheet.
[0038]
A series of operations to create a film original with this film printer, create a printing plate, attach it to a printing press, apply ink to the printing plate, and print on the paper is a large-scale operation and costs It also takes. For this reason, before the actual printing operation is performed, the proof image 61 is created by the printer 60 as described below, and the finished confirmation of the printed image 41 is performed in advance.
[0039]
In creating a proof image, image data created by plate collection on the workstation 20 is input to the personal computer 50. Here, the image data input to the personal computer 50 is description language data described in a so-called PDL (Page Description Language). In the personal computer 50, the image data is developed into a bitmap by a so-called RIP (Raster Image Processor). The converted CMYK four-color image data. The CMYK four-color image data is substantially the same as the image data for printing input to the film printer 30.
[0040]
The CMYK four-color printing image data is converted into CMYK four-color image data suitable for the printer 60 by referring to a profile having a LUT (Look Up Table) format inside the personal computer 50. The printer 60 receives CMYK four-color image data for the printer, and the printer 60 creates a proof image 61 based on the input CMYK four-color image data for the printer.
[0041]
Here, the profile having the LUT format that is referred to inside the personal computer 50 is a link profile formed by combining a print profile and a printer profile.
[0042]
Here, the print profile will be described first.
[0043]
For example, 0%, 10%,..., 100% of CMYK four-color halftone data is sequentially generated on the workstation shown in FIG. 1, and the halftone data thus generated is generated in accordance with the printing procedure described above. Create a color chart based on it. An image 41 shown in FIG. 1 is not an image representing a color chart, but a color chart in which a large number of color patches are arranged instead of the image 41 is printed, and each color patch constituting the color chart is printed. Is measured by the colorimeter 70 to obtain XYZ values (coordinate values in the CIEXYZ color space) of each color patch. By doing so, a print profile is created that represents the correspondence between the coordinate values in the color space of CMYK four colors and the coordinate values in the common color space (here, CIEXYZ color space).
[0044]
FIG. 2 is a conceptual diagram of a print profile.
[0045]
In this print profile, image data defined by CMYK is input, and the CMYK image data is converted into image data defined by XYZ values. Here, in order to distinguish from CMYK described later, C ₁ M ₁ Y ₁ K ₁ Is written.
[0046]
Next, the printer profile will be described.
[0047]
This printer profile creation method is the same as the print profile creation method, except that the output device that outputs the color chart is not a printer but a printer. That is, here, the CMYK four-color halftone data (here, C%), which is sequentially changed to 0%, 10%,..., 100% for each color by the personal computer 50 shown in FIG. ₂ M ₂ Y ₂ K ₂ The halftone data thus generated is sent to the printer 60, and the printer 60 prints out a color chart based on the halftone data. Although the image 61 shown in FIG. 1 is not an image representing a color chart, the printer 60 replaces the image 61 with the same type as the color chart created by printing on the printing press in order to create a print profile. The color chart is output, and each color patch constituting the color chart is measured by the colorimeter 70 to obtain an XYZ value (coordinate value in the CIEXYZ color space). In this way, C for the printer 60 ₂ M ₂ Y ₂ K ₂ A printer profile representing the correspondence between the coordinate values on the four color spaces and the coordinate values on the common color space (here, CIEXYZ color space) is constructed.
[0048]
FIG. 3 is a conceptual diagram of a printer profile.
[0049]
This printer profile contains C ₂ M ₂ Y ₂ K ₂ The net% data is input and its C ₂ M ₂ Y ₂ K ₂ Are converted into XYZ colorimetric data. Here, this C ₂ M ₂ Y ₂ K ₂ The printer profile for converting the halftone data of the color to XYZ colorimetric data is represented by P, and the reverse conversion, that is, the XYZ colorimetric data is represented by C. ₂ M ₂ Y ₂ K ₂ Printer profile for converting to% network data ^-1 It expresses.
[0050]
Here, the printer 60 is described as a printer that outputs an image based on the CMYK halftone data. However, for example, a printer that outputs an image based on RGB data is also used by the personal computer 50 in the RGB color space. By generating defined data and outputting a color chart, a printer profile suitable for the printer can be created in the same manner.
[0051]
However, here, the description will be made assuming that the printer 60 that outputs an image based on the CMYK halftone data is used.
[0052]
Note that there is not only one print profile and one printer profile. For example, the print profile is different for different printing machines, such as different inks and printing papers, even if the same printing machine is used. Created for each condition.
[0053]
Similarly, the printer profile is different for different printers, and even for the same printer, it is created for each different printing condition such as a difference in printing paper.
[0054]
FIG. 4 is a diagram showing a link profile obtained by combining a print profile and a printer profile.
[0055]
C for printing ₁ M ₁ Y ₁ K ₁ Is converted into XYZ colorimetric data by the printing profile T, and then the XYZ colorimetric data is converted to the printer profile P. ^-1 Again, but this time for the printer, C ₂ M ₂ Y ₂ K ₂ Convert to net% data. This print profile T and printer profile P ^-1 The link profile consisting of ₁ M ₁ Y ₁ The image data defined in the K color space is converted to C for printer. ₂ M ₂ Y ₂ K ₂ Is a profile for conversion to image data defined in the color space.
[0056]
Using the link profile created in this way, this time, for the image data representing the actual image, not the color chart, the C ₁ M ₁ Y ₁ K ₁ The image data expressed in% of the ₂ M ₂ Y ₂ K ₂ It is converted to image data expressed in halftone%.
[0057]
The printer 60 shown in FIG. ₂ M ₂ Y ₂ K ₂ The image data represented by the halftone% is sent, and the printer 60 prints out a proof image based on the sent image data.
[0058]
A link profile is created as described above, the image data for printing is converted into image data for a printer with reference to the link profile, and a proof image based on the image data for the printer is printed out by the printer 60 By doing so, it is possible to confirm in advance the finish of the printed image 41 shown in FIG.
[0059]
Conventionally, the print profile is used for the prior confirmation of the print image as described above.
[0060]
Next, the internal configuration of the printing system 40 constituting the printing and proof image creation system shown in FIG. 1 will be described.
[0061]
FIG. 5 is a schematic diagram showing a part of the printing machine.
[0062]
The printing paper P is conveyed in the direction of arrow A by a plurality of drums each rotating in the direction of the arrow. During the conveyance, the amount of ink adjusted by the ink key 411 is transferred to the roll 412, and the ink transferred to the roll 412 is stretched by many rolls 413 and wound around the roll 414. The ink supplied to the plate and transferred to the printing plate is transferred to a blanket made of rubber or the like wound around a roll 415 and transferred to an image pattern formed on the printing plate, and the ink on the blanket is transferred to the plate. It is applied on the printing paper P.
[0063]
FIG. 5 shows the configuration for one color of ink, but in the case of a printing machine, the components as shown in FIG. 5 include C (cyan), M (magenta), and M along the conveyance path of the printing paper P. Four printers (or more including special colors) are provided corresponding to each of the four colors Y (yellow) and K (black), and the printing paper P passes through the printing paper P by passing through them. A full-color print image is generated on the top.
[0064]
FIG. 6 is a schematic diagram of a computer operating as a portion of the printing press related to the embodiment of the present invention and an ink adjustment amount instruction device as an embodiment of the present invention.
[0065]
A plurality of (for example, 30) ink keys 411a, 411b,..., 411n arranged in the rotation axis direction of the roll 412 are arranged adjacent to the roll 412 shown in FIG. The opening degree of each of the ink keys 411a, 411b,..., 411n is adjusted for each ink key by the ink key control unit 418 that receives a command from the computer 510. The rotation speed of the roll 412 is controlled by the roll rotation control unit 417 that has received a command from the computer 510. Ink is supplied to the ink key from the ink supply unit 416, and the opening degree of each ink key and the roll 412 are set on the printing plate and further on the printing paper through the roll 412 and the many rolls 413 shown in FIG. Ink is supplied in an amount corresponding to the rotational speed.
[0066]
When the opening degree of each ink key 411a, 411b,..., 411n is adjusted, the ink supply amount of each part corresponding to each ink key 411a, 411b,. When the rotation speed of 412 is adjusted, the ink supply amount in the entire rotation axis direction of the roll 412 is adjusted. Also in FIG. 3, the ink keys 411a, 411b,..., 411n, the roll 412, the ink supply unit 416, the roll rotation control unit 417, and the ink key control unit 418 have a configuration corresponding to one color ink, and printing. The machine is provided with four colors of C, M, Y, and K (or more including special colors).
[0067]
The roll 418 is a roll responsible for transporting the printing paper P after a full color image is formed with four color inks made of CMYK. On the printing paper P, in addition to the original printing image P1, in its margin, A plurality of gray patches P2 are printed. These gray patches P2 are composed of CMY gray patches P21 composed of three CMY colors and K gray patches P22 composed of a single K color. These gray patches are halftone gray patches having a halftone dot area ratio of 50% for all of C, M, Y, and K, for example. Each of the CMY gray patch P21 and the K gray patch P22 is formed at a position corresponding to each of the plurality of ink keys 411a, 411b,.
[0068]
A colorimeter 500 is arranged opposite to the roll 418, and the colorimeter 500 measures the colorimetric values (here, CIEXYZ values) of the plurality of gray patches P2. These colorimetric values (CIEXYZ values) are surrounded by the computer 510, and the computer 510 adjusts the ink application thickness for each color ink of CMYK based on the acquired colorimetric values (shown in FIG. 6). The adjustment value for adjusting the opening degree of each ink key 411a, 411b,..., 411n in the configuration for one color, the adjustment value for the rotation speed of the roll 412, and other similar to the configuration for one color shown in FIG. Each adjustment value in the color configuration) is determined. If these adjustment values are described in the configuration for one color shown in FIG. 6, they are sent to the ink key control unit 418 and the roll rotation control unit 417 in the configuration for one color shown in FIG. In the roll rotation control unit 417, the opening degree of each ink key 411a, 411b,..., 411n and the rotation speed of the roll 412 are adjusted based on the sent adjustment values.
[0069]
Here, the colorimeter 500 is described as being mounted inside the printing press. However, the colorimeter 500 does not need to be mounted inside the printing press, and a printed product that has been printed is not necessary. Alternatively, the measurement may be performed by another colorimeter independent of the printing press.
[0070]
In the following, unless otherwise specified, when the configuration shown in FIG. 6 is cited, not only one color shown in FIG. 6 but also the corresponding configuration of each color of CMYK is cited.
[0071]
An ink adjustment amount instruction apparatus according to an embodiment of the present invention is configured by combining a computer 510 shown in FIG. 6 and an ink adjustment amount instruction program executed by the computer 510 as an embodiment of the present invention. In the following, first, the hardware of the computer 510 will be described.
[0072]
The computer 510 shown in FIG. 6 responds to key operations on the main body device 520, the image display device 530 that displays an image on the display screen 530a in accordance with an instruction from the main body device 520, and the main body device 520 in terms of external configuration. A keyboard 540 for inputting various information and a mouse 550 for inputting an instruction corresponding to, for example, an icon or the like displayed at that position by designating an arbitrary position on the display screen 530a are provided. The main unit 520 has an FD loading port 520a for loading a flexible disk (FD) and a CD-ROM loading port 520b for loading a CD-ROM.
[0073]
FIG. 7 is a hardware configuration diagram of a computer whose appearance is shown in FIG.
[0074]
As shown in FIG. 10, the main body 520 includes a CPU 521 that executes various programs, a main memory 522 that reads programs stored in the hard disk device 523 and develops them for execution by the CPU 521, and various programs. A hard disk device 523 in which data and data are stored, an FD drive 524 loaded with the FD 560 and accessing the loaded FD 560, a CD-ROM 570 loaded, and a CD-ROM drive 525 accessing the loaded CD-ROM 570, Connected to the colorimeter 500 shown in FIG. 6 and connected to the input interface 526 that receives the colorimetry / density data from the colorimeter 500, the ink key control unit 518, and the roll rotation control unit 417, the ink key control unit 518. And roll rotation control unit 417 An output interface 527 for sending adjustment value data for adjusting the ink application thickness is built in. These various elements, and the image display device 530, keyboard 540, and mouse 550 shown in FIG. Are connected to each other.
[0075]
FIG. 8 is a schematic configuration diagram of the ink adjustment amount instruction program stored in the CD-ROM.
[0076]
The CD-ROM 570 stores an ink adjustment amount instruction program 600 including a storage unit 610, an XYZ acquisition unit 620, a solid density calculation unit 630, an adjustment value calculation unit 640, and an adjustment value instruction unit 650. Here, the solid density calculation unit 630 constituting the ink adjustment amount instruction program 600 is composed of a dot gain calculation unit 631 and a solid density estimation unit 632.
[0077]
Here, the CD-ROM 570 storing the ink adjustment amount instruction program 600 shown in FIG. 8 is loaded into the CD-ROM drive 525 of the computer 510 shown in FIGS. 6 and 7, and the ink adjustment stored in the CD-ROM 570 is stored. The quantity instruction program 600 is uploaded to the computer 510 and stored in the hard disk device 523. When the ink adjustment amount instruction program 600 stored in the hard disk device 523 is expanded in the main memory 522 shown in FIG. 7 and executed by the CPU 521, the computer 510 is an embodiment of the ink adjustment amount instruction device of the present invention. Works as.
[0078]
The operation of the units 610 to 650 of the ink adjustment amount instruction program 600 shown in FIG. 8 will be described later.
[0079]
FIG. 9 is a functional block diagram showing an embodiment of the ink adjustment amount indicating device of the present invention.
[0080]
The ink adjustment amount instruction processing device 700 shown in FIG. 9 is constructed in the computer 510 by installing and executing the ink adjustment amount instruction program 600 shown in FIG. 8 on the computer 510 shown in FIGS. Is.
[0081]
The ink adjustment amount instruction program 700 shown in FIG. 9 includes a storage unit 710, an XYZ acquisition unit 720, a solid density calculation unit 730, an adjustment value calculation unit 740, and an adjustment value instruction unit 750. Here, the solid density calculation unit 730 further includes a dot gain calculation unit 731 and a solid density estimation unit 732.
[0082]
A storage unit 710, an XYZ acquisition unit 720, a solid density calculation unit 730 (dot gain calculation unit 731 and solid density estimation unit 732), an adjustment value calculation unit 740, and an ink adjustment amount instruction device 700 illustrated in FIG. The adjustment value instruction unit 750 constitutes the ink adjustment amount instruction program 600 shown in FIG. 8. The storage unit 610, the XYZ acquisition unit 620, and the solid density calculation unit 630 (dot gain calculation unit 631 and solid density estimation unit 632), respectively. 9 corresponds to the adjustment value calculation unit 640 and the adjustment value instruction unit 650. The units 710 to 750 of the ink adjustment amount instruction device 700 in FIG. 9 are the hardware of the computer 510, the operating system (OS), and the application program. The ink adjustment amount instruction program 60 shown in FIG. Components 610-650 is composed of only a part of the application program. When the ink adjustment amount instruction program 600 shown in FIG. 8 is installed in the computer 510 and executed, the operations of the respective units 610 to 650 of the ink adjustment amount instruction program 600 are as follows. The operations of the respective units 610 to 750 of the ink adjustment amount instruction program 600 of FIG. 8 will be described by describing the operations of the respective units 710 to 750 of the ink adjustment amount instruction apparatus 700 of FIG. It shall also serve.
[0083]
It should be noted that here, only the outline of the operations of the respective units 710 to 750 of the ink adjustment amount instruction device 700 of FIG. 9 will be described, and details thereof will be described with reference to FIGS. This will be described together with the description of the ink adjustment amount instruction method as one embodiment of the present invention.
[0084]
The ink adjustment amount instruction device 700 shown in FIG. 9 uses four color inks C, M, Y, and K on the printing paper P shown in FIGS. 5 and 6, and ink keys 411a, 411b,. By adjusting the opening of 411n and the rotation speed of the roll 412 (as described above, only the configuration for one color of C, M, Y, K is shown in FIG. 6), the application thickness of each color ink Specify each adjustment value for adjusting the coating thickness of each color ink when outputting a print image on the print paper P using a printing machine that outputs a halftone print image on the print paper P while adjusting It is a device to do.
[0085]
Here, the color profile 710a, the mapping relation 710b, and the correspondence relation 710c are stored in the storage unit 710 of the ink adjustment amount instruction device 700 of FIG.
[0086]
The color profile 710a corresponds to the print profile described with reference to FIG. 2, and includes coordinate values on a device color space (here, CMYK color space) having a dot area ratio of each color ink CMYK as coordinate axes, Based on the image data associated with the coordinate values, the printer is in a predetermined standard state (each predetermined color ink or a predetermined printing paper is used, each part of the printer, its environmental temperature and humidity, etc. Corresponding to coordinate values in a predetermined common color space (here, CIEXYZ color space) representing the color on the print image output by the printing press when it is in the standard state) It is.
[0087]
The mapping relation 710b is a mapping relation from a coordinate value associated with image data to a coordinate value including dot gain in a CMYK color space expressed by the colors of four CMYK inks used in a printing press. It is.
[0088]
Further, the correspondence relationship 710c indicates that each single color solid patch based on each single color patch data associated with the dot area ratio of 100% for each color ink is changed from the standard state when only the adjustment amount is set in the printing machine. By changing the coating thickness of each color ink by changing the output thickness for each ink, the solid density value of each single color solid patch obtained by measuring the solid density of each single color solid patch and the above adjustment value The corresponding relationship for each color ink.
[0089]
Further, the XYZ acquisition unit 720 constituting the ink adjustment amount instruction device 700 of FIG. 9 outputs the color profile 710a output on the printing paper P when the printing image is output on the printing paper P using the printing machine. Via the target color patch based on the target patch data further associated with the coordinate values on the CMYK color space further associated with the predetermined target coordinate values on the CIEXYZ color space (here, the gray patch shown in FIG. 6). P2 plays a role of acquiring coordinate values in the CIEXYZ color space obtained by performing color measurement with the colorimeter 500 (corresponding to this target color patch). The XYZ acquisition unit 720 mainly corresponds to the input interface 526 shown in FIG. 7 in hardware.
[0090]
Further, in the solid density calculation unit 730 constituting the ink adjustment amount instruction device 700 of FIG. 9, based on both the coordinate value in the CIEXYZ color space acquired by the XYZ acquisition unit 720 and the above target coordinate value, An estimated value of the solid density in the current state of the printing press is obtained for each color ink CMYK.
[0091]
The solid density calculation unit 730 includes a dot gain calculation unit 731 and a solid density estimation unit 732. Among them, the dot gain calculation unit 731 has coordinates in the CIEXYZ color space acquired by the XYZ acquisition unit 720. The coordinate value in the CMYK color space is obtained from the value based on the color profile 710a, the coordinate value in the CMYK color space associated with the target coordinate value in the CIEXYZ color space, and the CIEXYZ acquired by the XYZ acquisition unit 720. Both the coordinate values in the CMYK color space obtained from the coordinate values in the color space based on the color profile 710a are converted into the new coordinate values in the CMYK color space based on the mapping relation 70b. . Further, the solid density estimation unit 732 obtains an estimated value of the solid density in the current state of the printing press based on the two new coordinate values on the CMYK color space obtained by the dot gain calculation unit 731. When the solid density estimation unit 732 obtains an estimated value of the solid density in the current state of the printing press based on the two new coordinate values, the two new coordinate values and the printing press are in the standard state. The two density values corresponding to the two new coordinate values are obtained based on the standard solid density value at the time of the printing, and based on the two density values and the standard solid density value, the current value of the printing press is obtained. An estimated value of the solid concentration in the state is obtained. Details of this calculation will be described later.
[0092]
Further, in the adjustment value calculation unit 740 constituting the ink adjustment amount instruction device 700 of FIG. 9, the solid density for each color ink obtained by the solid density calculation unit 730 based on the correspondence 710 c stored in the storage unit 710. From the estimated value, the setting value of the opening degree of each ink key for each color ink and the adjustment value of the rotational speed of the roll for each ink (see the roll 412 in FIG. 6) are obtained. The adjustment value obtained in the section is indicated. In this embodiment, in the adjustment value instruction unit 750, the adjustment value of each ink key for each color ink and the adjustment value of the rotation speed of the roll for each color ink are displayed on the display screen of the image display unit 510 of the computer 510 shown in FIG. These adjustment values are sent to the ink key control unit 418 and the roll rotation control unit 417 to automatically adjust the opening degree and roll rotation speed of each ink key. The coating thickness of each color ink is automatically adjusted.
[0093]
However, the adjustment value instruction unit 750 of the ink adjustment amount instruction device 700 of FIG. 9 only gives instructions to the operator by displaying those adjustment values on the display screen, and the ink key control unit 418 and the roll rotation control. The command of the opening degree of each ink key and the roll rotation speed to the unit 417 may be left to the operator.
[0094]
Further details of the ink adjustment amount instruction device 700 of FIG. 9 will be described in the following description of an embodiment of the ink adjustment amount instruction method of the present invention described below.
[0095]
10 and 11 are a block diagram and a flowchart showing the flow of processing of the ink adjustment amount instruction method according to the embodiment of the present invention.
[0096]
First, as shown in step S11 of FIG. 11, the printing press is set to a standard state. In other words, CMYK inks are supplied to the printing machine, the printing paper to be printed is set, and the settings of each part of the printing machine are set to the conditions suitable for the printing. The environment such as temperature and humidity is also set to a predetermined environment.
[0097]
After the printing press is set to the standard state in this way, as described with reference to FIG. 2, the color chart is printed and the color patches constituting the color chart are measured to measure the color on the image data. A color profile (print profile) representing the correspondence between values (coordinate values in the CMYK color space) and colorimetric values on the print image (coordinate values in the CIEXYZ color space) is created (step S12 in FIG. 11). The created color profile is stored in the computer 510 shown in FIGS. 6 and 7 (color profile 710a in the storage unit 710 in FIG. 9).
[0098]
Also, when the printing press is in a standard state, only a set value of each ink key opening is changed from the standard state, and a single color patch in which the halftone dot area ratio of each of C, M, Y, and K is 100%. Is printed in the area corresponding to each ink key, and the density (solid density) of those single color patches is measured, thereby obtaining the correspondence between the set value of the ink key opening and the CMYK solid density (step S21). ). It is created for each ink key of one color ink of CMYK. FIG. 10C shows a correspondence relationship for one ink key of one color ink.
[0099]
The correspondence obtained in step S21 is also stored in the computer 510 shown in FIGS. 6 and 7 (correspondence 710c in the storage unit 710 in FIG. 9).
[0100]
As described with reference to FIG. 6, the ink application thickness is adjusted by both the opening degree of the ink key and the roll rotation speed. However, in order to simplify the explanation, the roll rotation speed is set to the standard. It is assumed that the ink application thickness is adjusted by adjusting the opening of the ink key.
[0101]
The case where the ink coating thickness is adjusted by both adjusting the roll rotation speed and adjusting the opening of each ink key will be described later.
[0102]
In step S31, the mapping relationship before and after the dot gain is calculated is obtained as follows.
[0103]
Here, M (magenta), Y (yellow), and K (black) mesh% (this may simply be expressed as M = O%, for example, for magenta. Regarding Y, K, and C (cyan)) Is also changed to C = 0%, 10%, 20%,..., 100% while keeping M = Y = K = 0%, and referring to the above color profile, (C, M, Y, K) = (0%, 0%, 0%, 0%), (10%, 0%, 0%, 0%), (20%, 0%, 0%, 0% ),..., (100%, 0%, 0%, 0%) corresponding to the value of X in CIEXYZ
[0104]
[Expression 1]

[0105]
C 'is obtained according to In this equation (2), X100 is the value of X in CIEXYZ associated with (C, M, Y, K) = (100%, 0%, 0%, 0%) by the color profile, X0 is the value of X in CIEXYZ associated with (C, M, Y, K) = (0%, 0%, 0%, 0%) by the same color profile. Here, C ′ obtained according to the equation (1) is associated with C when the value of X in the equation (1) is obtained with reference to the color profile. For example, X20 is obtained by referring to the color profile based on (C, M, Y, K) = (20%, 0%, 0%, 0%), and according to the equation (1),
[0106]
[Expression 2]

[0107]
Is obtained, C = 20% is associated with C ′ = 24%. At this time, C = 20% is the halftone on the image data before the dot gain is included, and C ′ = 24% is the halftone after the dot gain is included.
[0108]
The same applies not only to C (cyan) but also to M (magenta), Y (yellow), and K (black). For M (magenta), C = Y = K = 0% and M = 0. %, 10%, 20%,..., 100% and refer to the color profile to obtain Y of CIEXYZ.
[0109]
[Equation 3]

[0110]
Y100 and Y0 are Y values of CIEXYZ when M = 100% and 0% (C = Y = K is always 0%).
M 'after dot gain calculation is obtained according to the above, M before dot gain calculation and M' after calculation are associated with each other, and Y (yellow) is fixed at C = M = K = 0% and Y = Change the values to 0%, 10%, 20%, ..., 100% and refer to the color profile to obtain the value of Z of CIEXYZ.
[0111]
[Expression 4]

[0112]
However, Z100 and Z0 are values of Z of CIEXYZ when Y = 100% and 0% (C = M = K is always 0%).
Y ′ after the dot gain is calculated according to the above, Y before the dot gain is included and Y ′ after the dot gain are matched, and K (black) is fixed at C = M = Y = 0% and K = Change the values to 0%, 10%, 20%, ..., 100% and refer to the color profile to obtain the Y value of CIEXYZ.
[0113]
[Equation 5]

[0114]
Y100 and Y0 are Y values of CIEXYZ when K = 100% and 0% (C = M = Y is always 0%).
Then, K ′ after the dot gain is calculated is obtained, and K before the dot gain is calculated is associated with K ′ after the calculation.
[0115]
In step S31 in FIG. 11, the mapping relationship from the coordinate value on the image data before the dot gain calculation to the coordinate value after the dot gain calculation on the CMYK color space is obtained in this way. This mapping relationship is also stored in the computer 510 shown in FIGS. 6 and 7 (mapping relationship 710b of the storage unit 710 shown in FIG. 9).
[0116]
Here, the mapping relationship before and after the dot gain calculation is calculated by referring to the color profile obtained in step S11. However, for the above-described image data (for example, C (cyan), M = Y = K = Image data representing a plurality of single color patches fixed at 0% and changed to C = 0%, 10%, 20%,..., 100% (the same applies to M, Y, K)) C ′, M ′, Y ′, K ′ after the dot gain calculation is obtained by measuring the halftone dot area ratio of the single color patch printed on the printing paper and the image data before the dot gain calculation is calculated. The mapping relationship before and after the dot gain calculation may be obtained by associating C, M, Y, and K with C ′, M ′, Y ′, and K ′ after the dot gain calculation obtained by actual measurement.
[0117]
Each of the above steps S11, S12, S21, and S31 is a step in a preparation stage. After such preparation is completed, the process proceeds to an actual image printing scene.
[0118]
Here, as shown in FIG. 6, in addition to the actually required print image P <b> 1, a halftone gray patch P <b> 2 that is important for the print image P <b> 1 is provided at the position corresponding to each ink key in the margin of the print paper P. Printed. As described above, these gray patches P2 are composed of CMY gray patches with, for example, C = M = Y = 50% on which three colors of CMY ink are superimposed, and K single color ink, for example, K = 50. % K gray patch is included. These gray patches P2 are measured by the colorimeter 500 when the gray patches P2 of the printing paper P pass the position of the colorimeter 500, and CIEXYZ values are obtained (steps S41a and S41b in FIG. 11).
[0119]
The CIEXYZ value is transmitted to the computer 510 shown in FIG. 6 and is captured by the XYZ acquisition unit 720 in FIG.
[0120]
In the computer 510, the color profile 710a stored in the storage unit 710 shown in FIG. 9 is referred to, and the XYZ value obtained by measuring the CMY gray patch among the CIEXYZ values acquired by the XYZ acquisition unit 720 is calculated. CMY values that are device signals (coordinate values in the CMYK color space) are calculated under the constraint condition of K = 0% (step S42a), and from the XYZ values obtained by measuring the K gray patch, C = The device signal K is calculated under the constraint that M = Y = 0% (step S42b). When the device signal CMYK is calculated, the device signal CMYK is calculated from the CIEXYZ values obtained by the colorimetry in the colorimeter 500. In the same manner, the CIEXYZ value that is the target of the gray patch that is the object to be measured by the colorimeter 500 is also calculated. It is converted into device signal CMYK_tar based on the color profile. Here, “_tar” is a subscript indicating a target.
[0121]
The device signal CMYK_tar as the target value is the image data itself used for creating the gray patch. When the image data itself is stored, conversion from the target CIEXYZ to CMYK_tar is not necessary. .
[0122]
Next, in the computer 510, both of the device signals CMYK and CMYK_tar thus obtained are mapped relation 710b stored in the storage unit 710 in FIG. 9 (an example of cyan (C) in FIG. 10B). Dot gain correction is performed on the basis of (shown), and correction device signals C′M′Y′K ′ and C′M′Y′K′_tar including the dot gain are calculated (steps S43a and S43b). The processing in these steps S43a and S43b is processing in the dot gain calculation unit 731 constituting the solid density calculation unit 730 of the ink correction amount instruction apparatus 700 shown in FIG.
[0123]
Next, in steps S44a and S44b, density values are calculated from correction device signals C′M′Y′K ′ and C′M′Y′K′_tar including dot gain. Here, the following Murray-Davis formula is adopted to obtain the density value from the correction device signal. The cyan C′_tar of the corrected device signal C′M′Y′K′_tar obtained by adding the dot gain to the device signal CMYK_tar obtained from the target CIEXYZ is as follows.
[0124]
[Formula 6]

[0125]
It is. Where D _c 100 is the solid density of a single color patch of cyan (C) with a dot area ratio of 100% when the printing press is in the standard state including the opening of the ink key. This solid density D _c 100 is a correspondence 710c obtained in step S21 in FIG. 11 and stored in the storage unit 710 in FIG. 9 (correspondence between the set value of the opening degree of the ink key for adjusting the ink application thickness and the solid density). ) The solid density of the monochrome patch when the ink key is set to the standard opening.
[0126]
Based on the above equation (6), the correction device signal C′_tar including the dot gain is the density value D. _cp Converted to _tar.
[0127]
Similarly, the correction device signal C′M′Y′K ′ obtained by adding the dot gain to the device signal CMYK obtained from the measurement CIEXYZ obtained by measuring the gray patch P2 shown in FIG. For signal C ′:
[0128]
[Expression 7]

[0129]
In accordance with the correction device signal C ′ _cp Is obtained (step S44a).
[0130]
Here, the correction device signal C ′ generally shows a different halftone value compared to the correction device signal C′_tar. However, the halftone value has changed apparently, and the ink coating thickness has actually changed. The dot area ratio is considered to be constant (actually, the dot area ratio on the printed image changes slightly when the ink coating thickness changes, but the change is considered to be small. ).
[0131]
Therefore, here, two density values D calculated from the equations (6) and (7) are used. _cp _ _tar , D _cp Therefore, the correction device signals C′_tar and C ′ are regarded as the same (C′_tar = C ′), and the solid density value D in the current state of the printing press _c 100 'is obtained (step S45a).
[0132]
[Equation 8]

[0133]
The calculations of the above formulas (6) to (8) relate to cyan (C), but the same applies to magenta (M), yellow (Y), and black (K).
[0134]
That is, for magenta (M)
[0135]
[Equation 9]

[0136]
[Expression 10]

[0137]
However, D _M 100 is a solid density of a single color patch having a dot area ratio of 100% of magenta when the printing machine is in a standard state including the opening of the ink key.
Based on the density values D corresponding to M′_tar and M ′, respectively. _MP _ _tar , D _MP _ Is calculated (step S44a) and the formula
[0138]
## EQU11 ##

[0139]
The solid density value D in the current state of the press according to _M _100 'is calculated (step S45a).
[0140]
For yellow (Y),
[0141]
[Expression 12]

[0142]
[Formula 13]

[0143]
However, D _Y 100 is the solid density of a single color patch with a yellow dot area ratio of 100% when the printing machine is in the standard state including the opening of the ink key.
On the basis of the density values D corresponding to Y′_tar and Y ′, respectively. _YP _ _tar , D _YP Is calculated (step S44a) and the formula
[0144]
[Expression 14]

[0145]
The solid density value D in the current state of the press according to _Y _100 'is calculated (step S45a).
[0146]
In addition, for ink (K),
[0147]
[Expression 15]

[0148]
[Expression 16]

[0149]
However, D _K 100 is the solid density of a monochrome patch having a dot area ratio of 100% in black (K) when the printing press is in a standard state including the opening of the ink key.
Based on the density values D corresponding to K′_tar and K ′, respectively. _KP _ _tar , D _KP Is calculated (step S44b) and the equation
[0150]
[Expression 17]

[0151]
The solid density value D in the current state of the press according to _K _100 'is calculated (step S45b). The processes in steps S44a, S44b, S45a, and S45b are performed by the solid density estimation unit 732 included in the solid density calculation unit 730 of the ink adjustment amount instruction device 700 illustrated in FIG. 9, and the above (6) to (17). According to the formula, an estimate D of the solid density in the current state of the press _C 100 ', D _M 100 ', D _Y 100 ', D _K 100 'is required.
[0152]
As described above, the gray patch P2 shown in FIG. 6 includes the same number of CMY gray patches P21 as the number of ink keys and the same K gray patch P22 as the number of ink keys. The processing from S41b to steps S45a and S45b is performed for each of the arranged ink keys (see ink keys 411a, 411b,..., 411n for one color shown in FIG. 6), and C, M, Y, K An estimated value of the solid density is obtained for each color ink and each arranged ink key.
[0153]
In step S46 of FIG. 11, based on the correspondence obtained in step S21, that is, the correspondence 710c (see FIG. 10C) stored in the storage unit 710 of the ink adjustment amount instruction device 700 of FIG. An ink key adjustment value M is obtained from the solid density estimation value.
[0154]
The adjustment value M of the ink key is as follows for one ink key of one color ink.
M = f (D100 ′, D100) (18)
It can be expressed as Here, M is the adjustment value of the one ink key of the one color ink, D100 ′ is the estimated value of the solid density corresponding to the one ink key of the one color ink, and D100 is the ink key. The measured value of the solid density corresponding to the one ink key of the ink of one color when all the printing presses including the set value of the opening degree are in the standard state.
[0155]
FIG. 12 is a diagram showing the correspondence 710c stored in the storage unit 710 of the ink adjustment amount instruction device 700 of FIG. 9, that is, the correspondence between the solid density and the set value of the ink key opening.
[0156]
In step S46 of FIG. 11, as shown in the above equation (18), the solid density is the same as the solid density in the standard state based on both the solid density estimated value D100 ′ and the solid density value D100 in the standard state. An adjustment value M for adjusting the opening of the ink key so as to obtain a solid density is obtained. The processing in step S46 corresponds to the adjustment value calculation unit 740 of the ink adjustment amount instruction device 700 in FIG.
[0157]
The calculation of the adjustment value M in step S46 is performed for each color ink of CMYK and for each ink key.
[0158]
In step S47 of FIG. 11 (adjustment value instruction unit 750 of the ink adjustment amount instruction device 700 of FIG. 9), the adjustment value M obtained in step S46 (adjustment value calculation unit 740 of the ink adjustment amount instruction device 700 of FIG. 9) is obtained. The CMYK color inks are displayed on the display screen of the computer 510 and sent to ink key control units (ink key control units 418 for one color are shown in FIG. 6) corresponding to the CMYK color inks. The opening degree of each ink key is adjusted.
[0159]
FIG. 13 is a diagram showing the ink key opening adjustment value M displayed on the display screen 530a of the computer 510 shown in FIGS.
[0160]
Here, the adjustment value M for each color ink of CMYK and for each ink key (here, 13 ink keys of No. 1 to No. 13) is shown. “+0” indicates that the opening degree of the ink key may remain as it is, “+1” indicates that the opening degree of the ink key should be adjusted by +1 step, and “−1”. Indicates that the opening of the ink key should be adjusted by -1 step. The same applies to “+2”, “−2” and the like.
[0161]
In the present embodiment, the current ink key opening is set to “+0”, and relative adjustment values (“+1”, “−2”, etc.) from the current opening are displayed. Instead of the relative value from the current opening, for example, the absolute value of the opening of the ink key when the ink key is fully closed may be obtained and displayed.
[0162]
In the present embodiment, as described above, not only the adjustment value of the opening degree of each ink key is displayed, but also the adjustment value is an ink key control unit for each color ink of CMYK (the ink key control unit of FIG. 6). 418), the opening degree of each ink key is adjusted.
[0163]
However, in the adjustment value instruction unit 750 of the ink adjustment amount instruction device 700 of FIG. 9, the adjustment value is displayed on the display screen of the other computer 570 as shown in FIG. The transmission of the ink key opening degree command to the ink key control units corresponding to the CMYK inks such as the 6 ink key control unit 418 may be left to the operator.
[0164]
Next, the case where the ink application thickness is adjusted by controlling not only the ink key opening but also the rotation speed of the roll together with the ink key opening will be described.
[0165]
In this case, in step S21 in FIG. 11, using the printing machine in the standard state, not only the opening of the ink key but also the rotation of the rolls (each roll for supplying CMYK inks corresponding to the roll 412 in FIG. 6). Changing the speed from the standard state, printing single color solid patches of CMYK color inks (dot area ratio 100%), measuring the density of each single color patch, and measuring the solid density and ink key opening In addition to the correspondence with the set value (see FIG. 12), the correspondence between the solid density and the rotation speed setting value of the roll is obtained for each color ink of CMYK. These correspondences are stored in the storage unit 710 of FIG.
[0166]
FIG. 14 is a conceptual diagram showing a correspondence relationship for one color between the solid density and the roll rotation speed setting value.
[0167]
When adjusting the ink application thickness by adjusting both the rotation speed of the roll and the opening of the ink key, the estimated values of solid densities corresponding to each ink key (steps S45a and S45b in FIG. The solid density calculation unit 730) calculates the solid density relating to a series of ink keys corresponding to each roll (for example, a series of ink keys 411a, 411b,..., 411n corresponding to the roll 412 shown in FIG. 6). Estimated average value D100 ' _ave And the average value D100 ′ of the solid concentration estimated values _ave 14 is obtained based on the solid density D100 when the printing press is in the standard state including the opening of the ink key and the rotational speed of the roll. For each ink key corresponding to the roll, the solid density estimated value D100 ′ is corrected to a new estimated value as follows.
[0168]
New estimate D100 ′ =
Original estimate D100 '-(D100' _ave -D100) (18)
For each ink key, the new estimated value D100 ′ obtained based on the equation (18) is used, and the ink key adjustment value M is determined from the correspondence between the solid density and the ink key setting value as shown in FIG. Ask for.
[0169]
In step S47 in FIG. 11 (adjustment value instruction unit 750 in FIG. 9), the roll rotation speed adjustment values M corresponding to the CMYK color inks obtained as described above are used as the roll rotation speed adjustment values M corresponding to the CMYK color inks. Is sent to each roll speed control section (see roll speed control section 417 in the configuration for one color in FIG. 6) to control the rotation speed of each roll, and the rotation speed of each roll is adjusted and each adjustment value M of each ink key is set to CMYK. Is sent to each ink key control unit corresponding to each color ink (see ink key control unit 418 in the configuration for one color in FIG. 6) for each adjustment value M to adjust the opening of each ink key. At the same time, the adjustment value of each ink key shown in FIG. 13 and the adjustment value of the roll rotation speed are displayed on the display screen of the computer 510.
[0170]
FIG. 15 is a diagram illustrating a display example of the roll rotation speed adjustment value.
[0171]
Here, for each roll in charge of applying each color ink of CMYK, the rotational speed should be increased by 2.0 steps, the rotational speed should be increased by 1.0 steps, and the rotational speed should be decreased by 2.0 steps. And that the rotational speed should be increased by 1.0 step.
[0172]
In the case of the embodiments described so far, the correspondence between the solid density and the set value is obtained, an estimated value of the solid density is obtained from the colorimetric value of the halftone gray patch, and the ink is obtained from the estimated value of the solid density. An adjustment value for adjusting the coating thickness is obtained. In this case, the halftone dot area ratio of the halftone gray patch can be changed according to the characteristics of the printed image.
[0173]
Next, a second embodiment of the present invention that replaces the first embodiment described with reference to FIGS. 8 to 15 will be described.
[0174]
FIG. 16 is a schematic configuration diagram of an ink adjustment amount instruction program as a second embodiment of the present invention stored in a CD-ROM.
[0175]
The CD-ROM 570 stores an ink adjustment amount instruction program 800 including a storage unit 810, an XYZ acquisition unit 620, a coordinate mapping unit 830, an adjustment value calculation unit 840, and an adjustment value instruction unit 850.
[0176]
Here, the CD-ROM 510 storing the ink adjustment amount instruction program 800 shown in FIG. 16 is loaded into the CD-ROM drive 525 of the computer 510 shown in FIGS. 6 and 7, and the ink stored in the CD-ROM 570 is stored. The adjustment amount instruction program is uploaded to the computer 510 and stored in the hard disk device 523. When the ink adjustment amount instruction program 800 stored in the hard disk device 523 is expanded in the memory 522 shown in FIG. 7 and executed by the CPU 521, the computer 510 displays the ink adjustment amount instruction as the second embodiment of the present invention. Operates as a device.
[0177]
The operation of each unit 810 to 850 of the ink adjustment amount instruction program 800 shown in FIG. 16 will be described later.
[0178]
FIG. 17 is a functional block diagram showing an ink adjustment amount indicating device as a second embodiment of the present invention.
[0179]
An ink adjustment amount instruction device 900 shown in FIG. 17 is constructed in the computer 510 by installing and executing the ink adjustment amount instruction program 800 shown in FIG. 16 on the computer 510 shown in FIGS. It is.
[0180]
An ink adjustment amount instruction device 900 illustrated in FIG. 17 includes a storage unit 910, an XYZ acquisition unit 920, a coordinate mapping unit 930, an adjustment value calculation unit 940, and an adjustment value instruction unit 950.
[0181]
The storage unit 910, the XYZ acquisition unit 920, the coordinate mapping unit 930, the adjustment value calculation unit 940, and the adjustment value instruction unit 950 constituting the ink adjustment amount instruction device 900 shown in FIG. The instruction program 800 corresponds to the storage unit 810, the XYZ acquisition unit 820, the coordinate mapping unit 830, the adjustment value calculation unit 840, and the adjustment value instruction unit 850, respectively. However, the ink adjustment amount instruction device 900 in FIG. Each unit 910 to 950 is composed of a combination of hardware of the computer 510, an operating system (OS), and an application program, whereas each unit 810 to 850 of the ink adjustment amount instruction program 800 in FIG. It consists only of the application program part of them. When the ink adjustment amount instruction program 600 shown in FIG. 16 is installed in the computer 510 and executed, the operations of the respective portions 810 to 850 of the ink adjustment amount instruction program 800 are as follows. The operations of the units 810 to 850 of the ink adjustment amount instruction program 800 of FIG. 16 are described below by describing the operations of the units 710 to 750 of the ink adjustment amount instruction apparatus 700 of FIG. It shall also serve as an explanation.
[0182]
Here, as in the case of the first embodiment described above, the outline of the operations of the respective units 910 to 950 of the ink adjustment amount instruction device 900 of FIG. 17 will be described only. FIG. 19 will be used together with the description of the ink adjustment amount instruction method according to the second embodiment of the present invention.
[0183]
The ink adjustment amount indicating device 900 shown in FIG. 17 uses a printing machine that outputs a halftone print image on the printing paper shown in FIGS. 5 and 6 while adjusting the coating thickness of each color ink of CMYK. This is an apparatus for instructing each adjustment value for adjusting the coating thickness of each color ink of CMYK when outputting a halftone dot print image on the paper P. Here, the coating thickness of each color ink is performed by adjusting the opening of the ink keys 411a, 411b,..., 411n and the rotation speed of the roll 412 shown in FIG. Only the configuration for one color of CMYK is shown).
[0184]
Here, the color profile 910a and the correspondence 910b are stored in the storage unit 910 of the ink adjustment amount instruction device 900 of FIG.
[0185]
The color profile 910a corresponds to the print profile described with reference to FIG. 2, and includes coordinate values on a device color space (here, the CMYK color space) having a dot area ratio of each color ink CMYK as a coordinate axis; Based on the image data associated with the coordinate values, the printer is in a predetermined standard state (each predetermined color ink or a predetermined printing paper is used, each part of the printer, its environmental temperature and humidity, etc. Corresponding to coordinate values in a predetermined common color space (here, CIEXYZ color space) representing the color on the print image output by the printing press when it is in the standard state) It is.
[0186]
Also, the color space of each color ink of CMYK of the printing press (corresponding to a coordinate value corresponding to a halftone typically in the CIEXYZ color space) via the color profile (typically a coordinate value corresponding to a halftone) ( Target patch data further associated with coordinate values on the CMYK color space (here, for example, patch data representing halftone patches such as 50% halftone dot area ratio for C, M, Y, and K). CMY gray based on CMY gray patches in which cyan (C) ink, magenta (M) ink, and yellow (Y) ink are superimposed, and K gray patch containing only black (K) ink) For the patch and the K gray patch, when the printing press is in the standard state, only the setting value of the ink key opening is changed from the standard state so that the coating thickness of each color ink is not changed. A plurality of CMY gray patches and each K gray patch are measured to obtain respective coordinate values (each XYZ value) on the CIEXYZ color space, and each coordinate value (each XYZ value) on the obtained CIEXYZ color space is obtained. Value) is converted into a coordinate value (CMYK value) in the CMYK color space based on the color profile.
[0187]
The coordinate values in the CMYK color space thus obtained are associated with the above set values for each color ink of CMYK. The correspondence relationship 910b stored in the storage unit 910 in FIG. 17 is a correspondence relationship between the coordinate values in the CMYK color space obtained as described above and the setting values for each color ink of CMYK and for each ink key. It represents.
[0188]
Further, the XYZ acquisition unit 920 constituting the ink adjustment amount instruction device 900 in FIG. 17 outputs the target patch output on the printing paper P when the printing image is output on the printing paper P using the printing machine. On the CIEXYZ color space obtained by measuring the CMY gray patch and K gray patch (here, the gray patch P2 (CMY gray patch P21 and K gray patch P22) shown in FIG. 7 is received from the colorimeter 500. The hardware of the XYZ acquisition unit 720 is mainly played by the input interface 526 shown in FIG.
[0189]
In addition, in the coordinate mapping unit 930 of the ink adjustment amount instruction device 900 of FIG. 17, the coordinate value (XYZ value) in the CIEXYZ color space received by the XYZ acquisition unit 920 is used based on the color profile 910a stored in the storage unit 910. Thus, coordinate values in the CMYK color space are obtained.
[0190]
In addition, the adjustment value calculation unit 940 of the ink adjustment amount instruction device 900 in FIG. 17 stores the correspondence 910b (coordinate values in the CMYK color space and the ink key opening degree for adjusting the ink application thickness) stored in the storage unit 910. On the basis of the correspondence relationship with the adjustment value), the adjustment value for each color ink and for each ink key is obtained from each value of CMYK constituting the coordinate value in the CMYK color space obtained by the coordinate mapping unit 930.
[0191]
Further, the adjustment value instruction unit 950 constituting the ink adjustment amount instruction device 910 of FIG.
[0192]
In the present embodiment, the adjustment value instruction unit 950 displays the adjustment value of each ink key for each color ink on the display screen of the image display unit 510 of the computer 510 shown in FIG. Then, for each adjustment value corresponding to each color ink, it is sent to the ink key control section (each ink key control section 418 for one color is shown in FIG. 6) for each color ink, and the opening of each ink key is automatically set. Thus, the application thickness of each color ink on the printing paper P is automatically adjusted.
[0193]
However, the adjustment value instruction unit 950 of the ink adjustment amount instruction device 900 in FIG. 17 only gives instructions to the operator by displaying those adjustment values on the display screen, and each ink key to the ink key control unit is instructed. The opening command may be left to the operator.
[0194]
Further details of the ink adjustment amount instruction device 900 shown in FIG. 17 will be described in the following description of the ink adjustment amount instruction method according to the second embodiment of the present invention.
[0195]
18 and 19 are a block diagram and a flowchart showing the flow of processing of the ink adjustment amount instruction method according to the second embodiment of the present invention.
[0196]
Steps S51 and S52 in FIG. 19 are the same as steps S11 and S12 in FIG. 11 in the first embodiment described above. That is, here, the printing press is set to the standard state, the color chart is printed and measured by the printing press in the standard state, and the value on the image data (coordinate value in the CMYK color space) and the measurement on the print image are measured. A color profile representing the correspondence with color values (coordinate values in the CIEXYZ color space) is created. The created color profile is stored in the computer 570 shown in FIGS. 6 and 7 (color profile 910a in the storage unit 910 in FIG. 17).
[0197]
Further, in step S61 in FIG. 19, when the printing press is in the standard state, only the setting value of each ink key opening is changed from the standard state, and for example, the dot area ratio is 50% for all of CMYK. CMY gray patches and K gray patches based on predetermined target patch data are printed corresponding to each ink key, and the color values of the CMY gray patches and K gray patches are measured and coordinate values (XYZ values) in the CIEXYZ color space are measured. ), And converts each coordinate value (XYZ value) to a coordinate value in the CMYK color space based on the color profile created in step S52, thereby setting the opening value of each ink key and the CMY gray patch. And a correspondence relationship between the values of the K gray patches in the CMYK color space (CMYK values).
[0198]
The correspondence obtained in step S61 is also stored in the computer 510 shown in FIGS. 6 and 7 (the correspondence 910b in the storage unit 910 in FIG. 17).
[0199]
As described with reference to FIG. 6, the ink application thickness is adjusted by both the opening degree of the ink key and the roll rotation speed. However, in order to simplify the explanation, the roll rotation speed is set to the standard. It is assumed that the ink application thickness is adjusted only by adjusting the opening of the ink key.
[0200]
However, as described in the first embodiment, the ink application thickness may be adjusted by both adjusting the roll rotation speed and adjusting the opening of each ink key.
[0201]
In the present embodiment, the above steps S51, S52, and S61 are steps in the preparation stage, and after such preparation is completed, the process proceeds to an actual image printing scene.
[0202]
When actually printing an image on the printing paper P, as shown in FIG. 6, in addition to the printing image P1 that is actually required, the target used when obtaining the correspondence in the margin of the printing paper P in step S61. A halftone gray patch P2 (C, M, Y) based on the target patch data having the same dot area ratio as the patch data (here, as described above, for example, each CMYK ink has a dot area ratio of 50%). A CMY gray patch P21 on which ink is superimposed and a K gray patch P22) of a single K ink are printed.
[0203]
Here, the CMY gray patch P21 and the K gray patch P22 are printed one by one corresponding to the plurality of ink keys 411a, 411b,..., 411n arranged as shown in FIG. These gray patches P2 are measured by the colorimeter 500 when passing through the position of the colorimeter 500, and coordinate values (XYZ values) in the CIEXYZ color space are calculated (steps S71a and S71b in FIG. 19). ). This CIEXYZ value is transmitted to the computer 510 shown in FIG. 6 and taken into the computer 510 (XYZ acquisition unit 720 in FIG. 17).
[0204]
Then, the computer 510 refers to the color profile 910a stored in the storage unit 910 shown in FIG. 17 (the color profile created in step S52), and among the CIEXYZ values obtained by the XYZ acquisition unit 720, CMY gray A device signal (CMY value) is calculated from the XYZ value obtained by measuring the color of the patch under the constraint condition of K = 0% (step S72). From the XYZ value obtained by measuring the color of the K gray patch, A device signal (K value) is calculated under the constraint that C = M = Y = 0% (step S72b).
[0205]
When the device signal CMYK is calculated, not only the device signal CMYK is obtained from the CIEXYZ value obtained by the colorimetry with the colorimeter 500, but in the same way, the object of the colorimetry with the colorimeter 500 is obtained. The CIEXYZ value that is the target of the gray patch is converted to the device signal CMYK_tar based on the same color profile.
[0206]
The device signal CMYK_tar is the target patch data itself used to create the gray patch. When the target patch data is stored, the conversion from the target CIEXYZ to CMYK_tar is not necessary.
[0207]
Next, in step S73, based on the correspondence 910b (correspondence obtained in step S61 in FIG. 19 (see FIG. 18B)) stored in the storage unit 910 of the ink adjustment amount instruction device 900 in FIG. The ink key adjustment value M is calculated from the device signals CMYK and CMYK_tar obtained as described above. The ink key adjustment value M is obtained for each ink key of each ink of CMYK.
[0208]
The ink key adjustment value M is related to one ink key of one color ink (here, cyan (C)).
Mc = f (C, C _std ) …… (19)
It can be expressed as In the equation (19), Mc is an adjustment value of one ink key of cyan (C) ink, and C is a CMYK color space obtained from a color measurement value (XYZ value) of a CMY gray patch according to a color profile. Value of C, C _std Is the color profile from the colorimetric values (XYZ values) of the CMY gray patch for the ink key of cyan (C) ink when all of the printing press including the setting value of the ink key opening is in the standard state. C value on the CMYK color space obtained according to
[0209]
In step S74 of FIG. 19 (adjustment value instruction unit 950 of the ink adjustment amount instruction device 900 of FIG. 17), the adjustment value M obtained in step S73 (adjustment value calculation unit 940 of the ink adjustment amount instruction device 900 of FIG. 17). Is displayed on the display screen of the computer 510 (see FIG. 13), and is sent to the ink key control unit corresponding to each color ink of CMYK (FIG. 6 shows the ink key control unit 418 for one color). Thus, the opening degree of each ink key of each color ink of CMYK is adjusted.
[0210]
In the case of the first embodiment described above, a correspondence relationship between the solid density and the set value is obtained, an estimated value of the solid density is obtained from the colorimetric value of the halftone gray batch, and the ink application thickness is adjusted from the estimated value. Because the value is calculated, a gray patch with a halftone dot area ratio that is arbitrarily adjusted according to the characteristics of the print image is printed together with the print image, and ink application with a halftone dot area ratio is applied to the gray patch. Although the thickness can be adjusted, in the case of the second embodiment described here, the gray patch to be printed for obtaining the correspondence in step S61 in FIG. 19 and the margin at the time of actual image printing are printed. The gray patch needs to be a gray patch based on patch data with the same halftone dot area ratio, so if you want to adjust the ink application thickness of different halftones according to the characteristics of the printed image, for each halftone It is necessary to obtain the response relationship. However, in exchange for this, as can be seen from FIGS. 18 and 19, the calculation for adjusting the ink coating thickness during actual printing is simpler than in the case of the first embodiment.
[0211]
Next, a modification of the second embodiment described with reference to FIGS. 16 to 19 will be described.
[0212]
20 to 23 are schematic configuration diagrams of an ink adjustment instruction program stored in a CD-ROM, a functional block diagram of an ink adjuster instruction device, and an ink adjustment amount instruction method, respectively, in a modification of the second embodiment of the present invention. FIG. 6 is a block diagram showing the flow of processing and a flowchart showing the flow of processing of the ink adjustment amount instruction method.
[0213]
The ink adjustment amount instruction program 800 stored in the CD-ROM 570 of FIG. 20 is the same as FIG. 16 on FIG. Differences from the ink adjustment amount instruction program of FIG. 16 will be described together with the description of the ink adjustment amount instruction device of FIG. The relationship between the ink adjustment amount instruction program 800 in FIG. 20 and the ink adjustment amount instruction device 900 in FIG. 21 is the same as the relationship between the ink adjustment amount instruction program in FIG. 16 and the ink adjustment amount instruction device in FIG. That is, the ink adjustment amount instruction device 900 shown in FIG. 21 is constructed in the computer 510 by installing and executing the ink adjustment amount instruction program 800 shown in FIG. 20 on the computer 510 shown in FIGS. Is.
[0214]
The storage unit 910 constituting the ink adjustment amount instruction device 900 shown in FIG. 21 is different from the storage unit constituting the ink adjustment amount instruction device shown in FIG. 17 in that a mapping relation 910c is further stored. . This mapping relationship 910c defines the mapping relationship from the coordinate value associated with the image data to the coordinate value including the dot gain in the CMYK color space. The mapping relationship 910c of the ink adjustment amount instruction device 700 shown in FIG. It is created in the same manner as the mapping relation 710b stored in the storage unit 710.
[0215]
Further, the correspondence relationship 910b stored in the storage unit 910 of the ink adjustment amount instruction device 900 shown in FIG. 21 is the relationship between the CMYK coordinate values when the dot gain is taken into account, and the opening values of the ink keys. It defines the correspondence.
[0216]
Accordingly, in the coordinate mapping unit 930 of the ink adjustment amount instruction device 930 shown in FIG. 21, the CIEXYZ value obtained by the XYZ acquisition unit is converted into the CMYK value based on the color profile 910a (up to this point, FIG. In addition, the CMYK value is converted into a new CMYK value when the dot gain is taken into consideration based on the mapping relation 910c.
[0217]
Accordingly, the adjustment value calculation unit 940 obtains the dot gain obtained by the coordinate mapping unit 930 based on the correspondence 910b between the CMYK coordinate values and the ink key setting values when the dot gain is considered. The ink key adjustment value is obtained from the new CMYK value in consideration of the above.
[0218]
The ink adjustment amount indicating device of FIG. 21 is different from the ink adjustment amount indicating device of FIG. 17 only in the above points, and all other points are the same as the ink adjustment amount indicating device of FIG.
[0219]
These differences will be further described with reference to FIGS.
[0220]
22 is compared with FIG. 18, the mapping relationship of FIG. 22C is added, and C′M′Y′K which is CMYK when CMYK includes dot gain based on the mapping relationship. A conversion block to 'has been added. Further, the correspondence relationship shown in FIG. 22B is not the correspondence relationship between CMYK and ink key setting values as shown in FIG. 18, but C′M′Y′K ′ after considering dot gain and ink. Based on the correspondence relationship with the set value of the key, the ink key adjustment value M from C′M′Y′K ′ in which the dot gain is considered based on the mapping relationship of FIG. Is required.
[0221]
In FIG. 23, steps S81, S82a, and S82b are added compared to FIG. Also, steps S61 and S73 in FIG. 23 are slightly different from steps S61 and S73 in FIG.
[0222]
In step S81, the mapping relationship before and after the dot gain is calculated. The method for obtaining the mapping relationship in step S81 is the same as the method for obtaining the mapping relationship in step S31 in FIG. 11, and a duplicate description is omitted here.
[0223]
Further, in step S61 in FIG. 23, when the printing press is in the standard state, only the setting value of each ink key opening is changed from the standard state, and for example, the dot area ratio is 50% for any of CMYK. CMY gray patches and K gray patches based on predetermined target patch data are printed corresponding to each ink key, and the color values of the CMY gray patches and K gray patches are measured and coordinate values (XYZ values) in the CIEXYZ color space are measured. ) And the coordinate values (XYZ values) thereof are converted into coordinate values in the CMYK color space based on the color profile created in step S52.
[0224]
The processing so far is the same as the processing in step S61 in FIG. In step S61 in FIG. 23, the CMYK color when the dot gain is taken into consideration from the coordinate values in the CMYK color space obtained by the conversion based on the color profile based on the mapping relationship obtained in step S81. This is converted into a new coordinate value in the space, whereby the coordinate value (C′M′Y′K ′ value) in consideration of the set value of the ink key and the doggy gain in the CMYK color space of the CMY gray patch and the K gray patch. ).
[0225]
This correspondence is related to, for example, one ink key of cyan (C).
M _C = F (C ', C' _std ... (20)
It can be expressed as Where M _C Is the adjustment amount of that one ink key of cyan (C) ink, C ′ is the value of C in the CMYK color space obtained from the colorimetric value (XYZ value) of the CMY gray patch according to the color profile and mapping relationship, C ' _std Is the color profile from the colorimetric values (XYZ values) of the CMY gray patch for the ink key of cyan (C) ink when all of the printing press including the setting value of the ink key opening is in the standard state. And the value of C in the CMYK color space obtained according to the mapping relationship.
[0226]
Further, in steps S82a and S82b of FIG. 23, the CMYK values obtained in accordance with the color profile in steps S72a and S72b are changed to C′M′Y′K ′ values in consideration of dot gain based on the mapping relationship obtained in step S81. Converted.
[0227]
In step S73, it calculated | required by step S61. The correspondence between the ink key setting value and the device signal C′M′Y′K ′ when considering the dot gain of the gray patch is referred to, and the device signal C′M′Y ′ obtained in steps S82a and S82b is referred to. An ink key adjustment value M is calculated from K ′.
[0228]
Each of the above embodiments has been described by taking a printing machine as an example of the image output device according to the present invention. However, the image output device that is an object of the present invention is not limited to the printing machine, and the present invention is not limited thereto. Is an image output device that outputs a halftone image that expresses a density gradation or a color tone based on a halftone dot area ratio, and can be a general image output device having a mechanism for adjusting the ink application thickness.
[0229]
【The invention's effect】
As described above, according to the present invention, the ink adjustment amount is objectively calculated without depending on the skill of the operator.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a printing and proof image creation system including a printing system to which an embodiment of the present invention is applied.
FIG. 2 is a conceptual diagram of a print profile.
FIG. 3 is a conceptual diagram of a printer profile.
FIG. 4 is a diagram illustrating a link profile obtained by combining a print profile and a printer profile.
FIG. 5 is a schematic diagram showing a part of a printing machine.
FIG. 6 is a schematic diagram of a computer operating as a portion of the printing press related to the embodiment of the present invention and an ink adjustment amount instruction device as an embodiment of the present invention.
FIG. 7 is a hardware configuration diagram of a computer whose appearance is shown in FIG. 6;
FIG. 8 is a schematic configuration diagram of an ink adjustment amount instruction program stored in a CD-ROM.
FIG. 9 is a functional block diagram showing an embodiment of an ink adjustment amount instruction device of the present invention.
FIG. 10 is a block diagram illustrating a processing flow of an ink adjustment amount instruction method according to an embodiment of the invention.
FIG. 11 is a flowchart showing a process flow of an ink adjustment amount instruction method according to an embodiment of the present invention.
FIG. 12 is a diagram illustrating a correspondence relationship between solid density and a set value of the opening of the ink key.
13 is a diagram showing an ink key opening adjustment value M displayed on a display screen 530a of the computer 510 shown in FIGS. 6 and 7. FIG.
FIG. 14 is a conceptual diagram illustrating a correspondence value for one color between a solid density and a roll rotation speed setting value.
FIG. 15 is a diagram illustrating a display example of a roll rotation speed adjustment value.
FIG. 16 is a schematic configuration diagram of an ink adjustment amount instruction program as a second embodiment of the present invention stored in a CD-ROM.
FIG. 17 is a functional block diagram illustrating an ink adjustment amount instruction device according to a second embodiment of the invention.
FIG. 18 is a block diagram illustrating a processing flow of an ink adjustment amount instruction method according to a second embodiment of the invention.
FIG. 19 is a flowchart showing a process flow of an ink adjustment amount instruction method according to the second embodiment of the present invention;
FIG. 20 is a schematic configuration diagram of an ink adjustment instruction program stored in a CDROM in a modification of the second embodiment of the present invention.
FIG. 21 is a functional block diagram of an ink adjuster indicating device in a modification of the second embodiment of the present invention.
FIG. 22 is a block diagram showing a flow of processing of an ink adjustment amount instruction method in a modification of the second embodiment of the present invention.
FIG. 23 is a flowchart illustrating a process flow of an ink adjustment amount instruction method according to a modification of the second embodiment of the present invention.
[Explanation of symbols]
10 Color scanner
11 Document image
20 workstations
30 Film printer
40 Printing system
41 Print image
50 Personal computer
60 Printer
61 Proof Image
70 Colorimeter
411, 411a, 411b, ..., 411n Ink key
412 roll
416 Ink supply unit
417 Roll rotation control
418 Ink key control unit
500 Colorimeter
510 computer
520 Main unit
521 CPU
522 Main memory
523 hard disk device
524 FD drive
525 CD-ROM drive
526 input interface
527 output interface
528 bus
540 keyboard
550 mice
560 FD
570 CD-ROM
600 Ink adjustment amount instruction program
610 storage unit
620 XYZ acquisition unit
630 solid concentration calculator
631 Dot gain calculation section
632 Concentration estimation unit
640 Adjustment value calculation unit
650 Adjustment value instruction section
700 Ink adjustment amount instruction program
710 storage unit
720 XYZ acquisition unit
730 solid density calculator
731 Dot gain calculation section
732 solid concentration estimation unit
740 Adjustment value calculation unit
750 Adjustment value indicator
800 Ink adjustment amount instruction program
810 storage unit
820 XYZ acquisition unit
830 Coordinate mapping part
840 Adjustment value calculation unit
850 Adjustment value instruction section
900 Ink adjustment amount indicating device
910 storage unit
920 XYZ acquisition unit
930 Adjustment amount indicating device
940 Adjustment value calculation unit
950 Adjustment value indicator

Claims (15)

A halftone image on a recording medium using an image output device that outputs a halftone image on the recording medium by applying a plurality of color inks on a predetermined recording medium while adjusting the application thickness of each color ink. In the ink adjustment amount instruction method for instructing each adjustment amount for adjusting the coating thickness of each color ink,
The image output based on the coordinate value in the device color space having the dot area ratio of each color ink as the coordinate axis and the image data associated with the coordinate value when the image output device is in a predetermined standard state A first step of obtaining a color profile in which coordinate values in a predetermined common color space representing colors on a halftone dot image output from the device are associated;
A target color patch based on target patch data further associated with a coordinate value on the device color space associated with a predetermined target coordinate value on the common color space via the color profile; When the ink is in a predetermined standard state, by changing only the adjustment amounts from the standard state, a plurality of outputs are made while changing the coating thickness of each color ink, and the target color patch is measured to measure the color on the common color space. The coordinate value in the common color space is converted into the coordinate value in the device color space, and the correspondence between the coordinate value in the device color space and the adjustment amount is obtained for each color ink. The second step;
Obtaining coordinate values on the common color space colorimetry target color patches based on the target patch data outputted on the recording medium Upon outputting a halftone image on a recording medium by using the image output device The third step;
A fourth step of obtaining a coordinate value on the device color space from a coordinate value on the common color space obtained in the third step;
Based on the correspondence obtained in the second step, each adjustment amount for each color ink is obtained from the value for each color ink constituting the coordinate value in the device color space obtained in the fourth step. The fifth step;
And a sixth step of instructing each of the adjustment amounts obtained in the fifth step. 2. The ink adjustment amount instruction method according to claim 1, wherein the second step and the third step are steps of outputting a gray patch as the target color patch. The second step converts the coordinate value on the common color space obtained by measuring the target color patch into the coordinate value on the device color space based on the color profile, and converts the coordinate value on the device color space. A step of obtaining a correspondence relationship between coordinate values and the adjustment amount;
The fourth step is, claim 1, wherein the third a step asking you to coordinate values on the device color space based from the coordinate value on the common color space determined in the color profile in step The ink adjustment amount instruction method described. On the device color space, a mapping relationship from coordinate values associated with image data to coordinate values including dot gain is determined,
The second step converts coordinate values on the common color space obtained by measuring the target color patch into coordinate values on the device color space based on the color profile, and on the device color space. Converting the coordinate value to a new coordinate value on the device color space based on the mapping relationship, and obtaining a correspondence relationship between the new coordinate value and each adjustment amount;
The fourth step obtains a coordinate value on the device color space based on the color profile from the coordinate value on the common color space obtained in the third step and converts the coordinate value on the device color space to the mapping Obtaining a new coordinate value on the device color space based on the relationship,
The fifth step is a step of obtaining each adjustment amount for each color ink from a value for each color ink constituting the new coordinate value of the device color space obtained in the fourth step. The ink adjustment amount instruction method according to claim 1 . The mapping relationship includes an operation for calculating a halftone value for each color ink including dot gain based on the coordinate value on the common color space associated with the coordinate value on the device color space by the color profile. 5. The ink adjustment amount instruction method according to claim 4 , wherein the ink adjustment amount instruction method is determined by performing a plurality of coordinate values on the device color space . The mapping relationship outputs a plurality of color patches based on a plurality of patch data associated with a plurality of coordinate values on the device color space, and each color ink including a dot gain for each of the plurality of color patches. ink adjustment amount indicating method according to claim 4 Symbol mounting, characterized in that by measuring the net percent, are as previously defined. 7. The ink adjustment amount instruction method according to claim 5, wherein the plurality of coordinate values are coordinate values corresponding to gray colors having different densities . The sixth step, the claims, characterized in that said each of said adjustment amount obtained in the fifth step is for instructing toward the operator to manually adjust the coating thickness of each color ink of the image output device The ink adjustment amount instruction method according to 1 . In the sixth step, the adjustment amounts obtained in the fifth step are instructed to a coating thickness adjusting device that automatically adjusts the coating thickness of each color ink of the image output device. The ink adjustment amount instruction method according to claim 1 . A halftone image on a recording medium using an image output device that outputs a halftone image on the recording medium by applying a plurality of color inks on a predetermined recording medium while adjusting the application thickness of each color ink. In an ink adjustment amount indicating device that indicates each adjustment amount for adjusting the coating thickness of each color ink when outputting
The image output based on the coordinate value in the device color space having the dot area ratio of each color ink as the coordinate axis and the image data associated with the coordinate value when the image output device is in a predetermined standard state Corresponding to a predetermined target coordinate value on the common color space via the color profile associated with a coordinate value on a predetermined common color space representing a color on the halftone image output by the device The target color patch based on the target patch data further associated with the coordinate value on the device color space is changed from the standard state only for each adjustment amount when the image output device is in a predetermined standard state. By changing the application thickness of each color ink, a plurality of outputs are output for each color ink, and the target color patch is measured to obtain a coordinate value in the common color space. Thus, the correspondence relationship between the coordinate value on the device color space and the adjustment amount for each color ink obtained by converting the coordinate value on the common color space to the coordinate value on the device color space. And a storage unit for storing
When outputting a halftone image on a recording medium using the image output device, the common color space obtained by measuring a target color patch based on the target patch data output on the recording medium. A colorimetric data acquisition unit for acquiring coordinate values;
A coordinate mapping unit for obtaining a coordinate value on the device color space from a coordinate value on the common color space acquired by the colorimetric data acquisition unit;
Adjustment for obtaining each adjustment amount for each color ink from the value for each color ink constituting the coordinate value in the device color space obtained by the coordinate mapping unit based on the correspondence stored in the storage unit A quantity calculator;
The adjustment amount calculation section, wherein the to Louis ink adjustment amount indicating device further comprising an adjustment amount indicating portion to which the obtained instructs each adjusting amount. The adjustment amount instruction unit instructs each adjustment amount obtained by the adjustment amount calculation unit to an operator who manually adjusts the application thickness of each color ink of the image output device. The ink adjustment amount indicating device according to claim 10 . The adjustment amount instruction unit instructs the adjustment amount obtained by the adjustment amount calculation unit to an application thickness adjusting device that automatically adjusts the application thickness of each color ink of the image output device. The ink adjustment amount indicating device according to claim 10, wherein: A halftone dot is formed on the recording medium by applying a plurality of color inks on a predetermined recording medium while adjusting the coating thickness of each color ink. Ink that operates as an ink adjustment amount indicating device that indicates each adjustment amount for adjusting the coating thickness of each color ink when a halftone image is output on the recording medium using an image output device that outputs an image In the adjustment amount instruction program,
The image output based on the coordinate value in the device color space having the dot area ratio of each color ink as the coordinate axis and the image data associated with the coordinate value when the image output device is in a predetermined standard state Corresponding to a predetermined target coordinate value on the common color space via the color profile associated with a coordinate value on a predetermined common color space representing a color on the halftone image output by the device The target color patch based on the target patch data further associated with the coordinate value on the device color space is changed from the standard state only for each adjustment amount when the image output device is in a predetermined standard state. By changing the application thickness of each color ink, a plurality of outputs are output for each color ink, and the target color patch is measured to obtain a coordinate value in the common color space. Thus, the correspondence relationship between the coordinate value on the device color space and the adjustment amount for each color ink obtained by converting the coordinate value on the common color space to the coordinate value on the device color space. And a storage unit for storing
When outputting a halftone image on a recording medium using the image output device, the common color space obtained by measuring a target color patch based on the target patch data output on the recording medium. A colorimetric data acquisition unit for acquiring coordinate values;
A coordinate mapping unit for obtaining a coordinate value on the device color space from a coordinate value on the common color space acquired by the colorimetric data acquisition unit;
Adjustment for obtaining each adjustment amount for each color ink from the value for each color ink constituting the coordinate value in the device color space obtained by the coordinate mapping unit based on the correspondence stored in the storage unit A quantity calculator;
Features and to Louis ink adjustment amount instruction program to be operated as an ink adjustment amount indicating device with an adjusting amount instructing unit for instructing the respective adjustment amount determined by the adjustment amount calculation section. The adjustment amount instruction unit instructs each adjustment amount obtained by the adjustment amount calculation unit to an operator who manually adjusts the application thickness of each color ink of the image output device. The ink adjustment amount instruction program according to claim 13 . The adjustment amount instruction unit instructs the adjustment amount obtained by the adjustment amount calculation unit to an application thickness adjusting device that manually adjusts the application thickness of each color ink of the image output device. claim 1 3 ink adjustment amount instruction program, wherein.

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