200843478 P51950197TW 23076twf.doc/n 九、發明說明： 【發明所屬之技術領域】 本發明是有關於-種影像處理的裝置 別是有關於一種影像強化的裝置及其方、、，、万去，且特 【先前技術】 ^ 隨著數位科技的大幅進步，再加上網 :術二高度發展，許多影像都希望可以轉“數;二：:200843478 P51950197TW 23076twf.doc/n IX. Description of the Invention: [Technical Field] The present invention relates to an apparatus for image processing, and relates to an apparatus for image enhancement and a method thereof, and Special [Prior Art] ^ With the great advancement of digital technology, plus the Internet: The second development of the second high, many images hope to be able to transfer "number; two::
接擷取實物景象。 相機來直 做越f於的:益精進’數位相機的體積也越 做越小，以便卩近身攜f。甚至將數位相機與其他的行 置結合，例如手機相機，也是目前普遍的趨勢。然而，: 般的數位相機都是配備定焦的鏡頭，然後使用數:變焦: 方式來放大影像，以滿足使用者的需求。因此，如何讓影 像經過數位放大後，對於使用者來說仍然有足夠好的影像 品質’是很重要的。 ' 在數位相機的影像處理流程中，會有一個邊緣強化 (edge enhancement)的步驟。其中，邊緣強化的步驟可以增 大影像邊緣之間的對比，以讓晝面顯得更銳利。 請參照圖1A〜1C，其繪示一種習知之影像邊緣強化的 示意圖’其中橫轴為畫素(pixel)編5虎’縱轴為影像強度大 小。在圖1A中，曲線101為影像訊7虎經過數位放大後， 影像訊號中一個邊緣的曲線圖。在圖1B中，曲線1〇3是 曲線101作邊緣偵測後的結果。在此可明顯看出在邊緣的 4 200843478 P51950197TW 23076twf.doc/n 兩端會有強烈的響應值，而邊緣中間的影像強度為零。而 此影像強度為零的位置，稱之為零交點(zer〇cr〇ssing)。在 圖1C中，曲線105為曲線101和103相加之後的結果。 在圖1C中，可以明顯看出邊緣兩端的對比被拉開。 圖2繪示為另一習知之影像邊緣強化之示意圖，其中 橫軸是晝素(pixel)編號，縱軸是影像強度大小。在圖2A 中’曲線201為影像訊號經過數位放大後，影像訊號中一 個邊緣的曲線圖。在圖2Β中，曲線203是在影像訊號作 邊緣偵測後，再進行數位放大後所得的結果。在圖2c中， 曲線205為曲線201和203相加之後的結果。 然而，在習知之影像邊緣強化技術中，是以拉大邊緣 兩端的對比，來增加邊緣中間的斜率。若曲線1〇3和2〇3 乘上較小的增益值，則無法提供足夠的放大倍率。相對的， 若曲線103和203乘上較大的增益值，則會產生多餘的色 彩衍生物(artifact)產生。 【發明内容】 本發明提供一種影像強化之方法，可以增加影像邊緣 之對比。 、 本發明提供一種影像強化裝置，可以增加影像邊緣之 對比。 、 本务明^供一種影像強化之方法’包括下列步驟。將 :影像訊號進行邊緣偵測，用以產生影像響應。接著，將 、/像％應進行門模值偵測，而使影像響應區分為正影像響 應和負景>像響應。接著，將影像訊號、正影像響應以及負 200843478 P51950197TW 23〇76twfdoc/n 影像響應進行訊號處理。 本發明提供一種影像強化裝置，包括門檻值偵測單元 7增益控制單元。其中，門檻值偵測單元用以將影像訊號 區为為正影像響應和負影像響應。而增益控制單元耦接至 門檻值偵測單元，並依據正影像響應和負影像響應以產生 補償響應值。 由於本發明所提供的影像強化的方法，可以將影像響 fTake in the real scene. The camera is straightforward and more versatile: the size of the digital camera is getting smaller and smaller, so that it can be close to the body. Even combining digital cameras with other devices, such as cell phone cameras, is a common trend. However, the general digital camera is equipped with a fixed focus lens, and then use the number: zoom: way to enlarge the image to meet the needs of users. Therefore, how to make the image digitally magnified is still very good for the user. In the image processing flow of a digital camera, there is an edge enhancement step. Among them, the edge enhancement step can increase the contrast between the edges of the image to make the face look sharper. 1A to 1C, a schematic diagram of a conventional image edge enhancement is shown, wherein the horizontal axis is a pixel and the vertical axis is the image intensity. In Fig. 1A, a curve 101 is a graph of an edge of the image signal after the digital signal is digitally amplified. In Fig. 1B, the curve 1〇3 is the result of the edge detection of the curve 101. It is apparent here that there is a strong response at both ends of the edge of the 4 200843478 P51950197TW 23076twf.doc/n, and the image intensity in the middle of the edge is zero. The position where the image intensity is zero is called zero crossing point (zer〇cr〇ssing). In Fig. 1C, curve 105 is the result of the addition of curves 101 and 103. In Figure 1C, it is apparent that the contrast at both ends of the edge is pulled apart. FIG. 2 is a schematic diagram showing another conventional image edge enhancement, wherein the horizontal axis is a pixel number and the vertical axis is an image intensity. In Fig. 2A, the curve 201 is a graph of an edge of the image signal after the image signal is digitally amplified. In Fig. 2, curve 203 is the result of digitally magnifying the image signal after edge detection. In Figure 2c, curve 205 is the result of the addition of curves 201 and 203. However, in the conventional image edge enhancement technique, the contrast between the two ends of the edge is increased to increase the slope in the middle of the edge. If the curves 1〇3 and 2〇3 are multiplied by a smaller gain value, sufficient magnification cannot be provided. In contrast, if curves 103 and 203 are multiplied by a larger gain value, an extra color artifact is produced. SUMMARY OF THE INVENTION The present invention provides a method of image enhancement that can increase the contrast of image edges. The present invention provides an image enhancement device that can increase the contrast of image edges. The method for providing an image enhancement includes the following steps. The image signal is edge-detected to generate an image response. Next, the /, image % should be gated value detection, and the image response is divided into positive image response and negative image > image response. Next, the image signal, the positive image response, and the negative 200843478 P51950197TW 23〇76twfdoc/n image response are signal processed. The invention provides an image enhancement device comprising a threshold value detecting unit 7 gain control unit. The threshold value detecting unit is configured to use the image signal area as a positive image response and a negative image response. The gain control unit is coupled to the threshold detection unit and generates a compensation response value according to the positive image response and the negative image response. Due to the image enhancement method provided by the present invention, the image can be sounded f
應區分為正影像響應和負影像響應，透過增益值大小的控 制，可以產生補償響應值。藉此，本發明將放大後的影像 訊號與補償響應仙加後，可祕高影像輕之間的銳利 度。 為讓本發明之上述特徵和優點能更明顯易懂，下文特 舉一些實施例，並配合所附圖式，作詳細說明如下。 【實施方式】 f 3纟會福依照本發明之—實施例的—種影像強化裝 路圖。請參關3，影像強化裝置_包括邊緣偵 ^早兀30卜門檻值偵測單元3〇3、訊號處理單元兕5、增 益^單元3〇7以及加法器·。其中，邊緣偵測單元^ 馬、,^門才皿值偵測單元303，而門植值债測單元303搞接 =盈控制單元3〇7。訊號處理單元3GS配置於門植值偵 =兀3〇3和增益控制單元3〇7之間。此外，加法器, 麵接至增盈控制單元307。 ，4 依照本發明之—實例之影像強化之控制方 法的机程圖。請合併參照圖3和圖4，當邊緣偵測單元期 200843478 P51950197TW 23076twf.doc/n 接收衫像sfU虎Im時，可以如步驟§4〇1所述，將影像訊 號Im進行邊緣偵測，並產生一影像響應。 邊緣偵測單70 301所接收的影像訊號Im，可以是如圖 5旦A所緣示。在目5A巾，橫車由是晝素(pixel)編號，縱軸是 衫像強度大小。在本實施例中，邊緣偵測單元3〇1會將影 像汛唬Im進行二次微分。當影像訊號Im經過二次微分 後，在邊緣的兩端會產生很大的響應，例如圖5B所繪示 之波形。 在本貝鉍例中，邊緣偵測單元3〇1例如是二次微分濾 波器或是拉普拉斯濾波器(Laplacian糧er)。當影像訊號Im 、、、工過邊緣偵測後，將產生之影像響應傳送至門檻值偵測單 元 303。 、、，當門檻值偵測單元303接收到邊緣偵測單元3〇丨所傳 运的影像響鱗，會將接收到的影像響麵分為正影像響 應Imp和負影像響應Imn(步驟S4〇3)，如圖咒所繪示: 在圖冗中，影像強度大於0的部份是正影像響應Imp。相 對地，影像強度小於0的部份是負影像響應〗^^^ 門檻值偵測單元303會將正影像響應Imp和負影像響 w Imn傳送至成號處理單元305。藉此，訊號處理單元305 可以將正影像響應Imp和負影像響應Imn分別放大至一預 ，值，例如是圖5D所繪示。另外，訊號處理單元3〇5將 影像訊號Im放大至一預設值後(例如是圖5E所繪示），並 傳送至加法器3〇9(步驟S405)。 請繼續合併參照圖3和圖4，增益控制單元3〇7會依 7 200843478 F5119 7TW 23 076twf.doc/n 據經過放大後的正影像響應Imp和負景 生補償響應值傳送至加法器309(步驟^4^響應Imn，而產 在圖5D中，將影像響應區分為第〜〇7)。 二子集範圍R2以及第三子集範圍R3子集範圍幻、第 圍R1為負影像響應Imn為零的區域，二、中，第一子集範 為正影像響應Imp為零的區域，第三子^二子集範圍R2 像響應Imp和負影像響應Imn皆不為^把11 R3為正影It should be divided into positive image response and negative image response. Through the control of the gain value, the compensation response value can be generated. Therefore, the present invention can increase the sharpness between the image and the compensation signal after the enlarged image signal. The above described features and advantages of the invention will be apparent from the following description. [Embodiment] An image-enhanced circuit diagram according to an embodiment of the present invention is provided. Please refer to 3, Image Enhancement Device _ includes edge detection, early detection, 3 〇 threshold detection unit 3〇3, signal processing unit 兕5, gain unit 3〇7, and adder·. The edge detection unit ^ horse, the door value detection unit 303, and the door value debt measurement unit 303 engages the profit control unit 3〇7. The signal processing unit 3GS is disposed between the gate value detection 兀3〇3 and the gain control unit 3〇7. In addition, the adder is connected to the gain control unit 307. 4 is a machine diagram of a control method of image enhancement according to an embodiment of the present invention. Please refer to FIG. 3 and FIG. 4 together. When the edge detection unit period 200843478 P51950197TW 23076twf.doc/n receives the shirt image like sfU tiger Im, the image signal Im can be edge-detected as described in step §4〇1, and Generate an image response. The image signal Im received by the edge detection unit 70 301 may be as shown in FIG. In the head of the 5A towel, the crossbar is numbered by the pixel and the vertical axis is the intensity of the shirt image. In this embodiment, the edge detecting unit 3〇1 will perform second-order differentiation of the image 汛唬Im. When the image signal Im is subjected to the second differentiation, a large response is generated at both ends of the edge, such as the waveform shown in Fig. 5B. In the present example, the edge detecting unit 3〇1 is, for example, a quadratic differential filter or a Laplacian filter (Laplacian grain er). When the image signal Im, , and the detected edge are detected, the generated image response is transmitted to the threshold value detecting unit 303. When the threshold detection unit 303 receives the image scale transmitted by the edge detection unit 3, the received image surface is divided into a positive image response Imp and a negative image response Imn (step S4〇). 3), as shown in the figure: In the picture redundancy, the part with image intensity greater than 0 is the positive image response Imp. Conversely, the portion where the image intensity is less than 0 is the negative image response. The threshold value detecting unit 303 transmits the positive image response Imp and the negative image response w Imn to the number processing unit 305. Thereby, the signal processing unit 305 can respectively enlarge the positive image response Imp and the negative image response Imn to a pre-value, for example, as shown in FIG. 5D. In addition, the signal processing unit 3〇5 enlarges the image signal Im to a predetermined value (for example, as shown in Fig. 5E), and transmits it to the adder 3〇9 (step S405). Please continue to merge with reference to FIG. 3 and FIG. 4, the gain control unit 3〇7 will transmit to the adder 309 according to the amplified positive image response Imp and the negative scene compensation response value according to 7 200843478 F5119 7TW 23 076twf.doc/n (step ^4^ responds to Imn, and is produced in Fig. 5D, and the image response is divided into the first ~ 〇 7). The second subset range R2 and the third subset range R3 subset range illusion, the circumference R1 is the area where the negative image response Imn is zero, and the second subset is the area where the positive image response Imp is zero, and the third Sub ^ 2 subset range R2 like response Imp and negative image response Imn are not ^ 11 11 R3 is the shadow
以下將詳細說明產生補償響應值的沭 Λ 中，對於每一個子集範圍可以提供不同^询二在本實施例 言，若是影像響應落在第一子集範圍Rl、增盃值。舉例而 單元307產生-第-增益值gainl心：像控: 理，而處理步驟如下式·· 篆胃應進订處 R=Rpx gainl 其中，R為補償響應值，Rp為正影像響應值。 則增益控制 響應進行處 若是影像響應落在第二子集範圍玟2内， 早凡307產生弟—增益值gain2來對旦;〆务 理，而處理步驟如下式： 〜 R二Rnx gain2 其中，Rn為負影像響應值。 另外，若是影像響應落在第三子集範圍R3内，並且 ，則增益控制單元307產生一第三增益值 來_影像響應進行處理，而處理步驟如下所示： R^Rpx gainl—Rnx gain3 δ 200843478 P51950197TW 23 〇76twf.doc/n 相對地，若是影像響應落在第三子集範圍R3内，並 且Rp<-Rn’則增盈控制單元3〇7利用一第四增益值喊4 來對影像響應進行處理，而處理步驟如下所示： R^Rnx gain2~Rpx gain4 ° 在本實施例中，第三增益可以大於第一增益，而第四增益 則大於第二增益。 另外，逖需要考慮一種情形，就是當正影像響應值 (、Rp等於影像響應值-Rn時，則補償響應值例如是最靠近此 點的周圍兩點（其中—點在Rp》Rn的範圍内，另一點在 Rp<-Rn的範圍内）之響應值的平均。 需注意的是，在實務操作上可依實際的需求調整上述 不同子集範圍之增益值以及補償響應值。另外，產生的補 償響應值例如是圖5F。 接著’進行步驟S409，藉由加法器309將經過數位放 ^後的影像訊號與補償響應值相加，其相加後的結果例如 是圖5G所繪示。值得注意的是，圖5A和圖5G的圖形相 U ^度很高。因此，本發明之影像強化的控制方法，可以使 得影像訊號經過數位放大後，提昇影像邊緣之銳利度。 綜上所述，本發明所提供的影像強化的控制方法，可 以將衫像響應區分為正影像響應和負影像響應，透過增益 值大小的控制，可以產生補償響應值。藉此，本發明將放 大後的影像訊號與補償響應值相加後，可以提高影像邊緣 之間的銳利度。 雖:、、:本务明已提供了多組實施例揭露如上，然其並非 9 200843478 FM^Uiy/TW 23076twf.doc/n :::艮明’任何所屬技術領域中具有通常知識者， 在不脫縣發日月之精神和範_，t可作些許之更動與潤 ，發明之__當視後附之申請專利範圍所界 疋f马竿。 【圖式簡單說明】 圖1A〜1C!會示為習知之影像邊緣強化的示意圖。 圖2A〜2C緣不為另_習知之影像邊緣強化之示意圖。 ，3繪不為依照本發明之一實施例的一種影 置之電路圖。 圖4緣不為依照本發明之一實例之影像強化之控制方 法的流程圖。 圖5A〜5G繪示為本發明之影像邊緣強化的示意圖。 【主要元件符號說明】 o 邊緣偵測單元 門檻值偵測單元 訊號處理單元 增益控制單元 加法器 、S403、S405、S407、S409 :步驟 301 303 305 307 309 ： S401In the following, the 产生 产生 for generating the compensation response value can be provided for each subset range. In the present embodiment, if the image response falls within the first subset range R1, the increment value is increased. For example, unit 307 generates a -first gain value gainl heart: image control: and the processing step is as follows: · stomach should be ordered R = Rpx gainl where R is the compensation response value and Rp is the positive image response value. Then, if the gain control response is performed, the image response falls within the second subset range 玟2, and the 307 generates the brother-gain value gain2 to be tuned; the processing step is as follows: ~ R 2 Rnx gain2 where Rn is the negative image response value. In addition, if the image response falls within the third subset range R3, and the gain control unit 307 generates a third gain value to process the image response, the processing steps are as follows: R^Rpx gainl—Rnx gain3 δ 200843478 P51950197TW 23 〇76twf.doc/n In contrast, if the image response falls within the third subset range R3, and Rp<-Rn' then the gain control unit 3〇7 uses a fourth gain value to call the image 4 The response is processed, and the processing steps are as follows: R^Rnx gain2~Rpx gain4 ° In this embodiment, the third gain may be greater than the first gain, and the fourth gain is greater than the second gain. In addition, 逖 need to consider a situation, that is, when the positive image response value (, Rp is equal to the image response value -Rn, then the compensation response value is, for example, the two points closest to the point (where - the point is in the range of Rp"Rn The other point is the average of the response values in the range of Rp<-Rn. It should be noted that the gain value and the compensation response value of the different subset ranges can be adjusted according to actual needs in practical operation. The compensation response value is, for example, FIG. 5F. Then, in step S409, the image signal after the digital display is added to the compensation response value by the adder 309, and the added result is, for example, as shown in FIG. 5G. It is noted that the graphs of FIGS. 5A and 5G have a high U ^ degree. Therefore, the image enhancement control method of the present invention can enhance the sharpness of the image edges after the image signals are digitally amplified. The image enhancement control method provided by the invention can distinguish the shirt image response into a positive image response and a negative image response, and can generate a compensation response value by controlling the magnitude of the gain value. The invention adds the amplified image signal and the compensation response value, and can improve the sharpness between the edges of the image. Although:,: The present invention has provided a plurality of sets of embodiments to disclose the above, but it is not 9 200843478 FM ^Uiy/TW 23076twf.doc/n :::艮明' Anyone who has the usual knowledge in the technical field, can not make a difference between the spirit of the sun and the moon and the _, t can make some changes and run, the invention __ Figure 1A~1C! will show a schematic diagram of the image edge enhancement of the conventional image. Figure 2A~2C is not the edge of another image. 3 is a circuit diagram of a shadowing method according to an embodiment of the present invention. FIG. 4 is not a flowchart of a method for controlling image enhancement according to an example of the present invention. FIGS. 5A to 5G are diagrams. A schematic diagram of image edge enhancement according to the present invention. [Main component symbol description] o Edge detection unit threshold detection unit signal processing unit gain control unit adder, S403, S405, S407, S409: Step 301 303 305 307 309: S401