437253 B7 五、發明說明（1 ) 本申請案擁有下列美國專利申請案之優先權，其序號爲 60/065,855 ’ 名稱爲 “Multipurpose Digital Signal Processing + System”（多用途數位信號處理系統），申請日期：1997年 11月14日，其内容在此直接併供參考。 發明範疇 本發明大致有關於三維（3D)音效，尤其有關於使用於3 D 數位音效應用中聽覺間時間延遲之數位應用。 發明背景 許多高端消耗裝置提供三維（3D)音效的選擇，容許岭聽 音效時更眞實的感受。在某些應用中，3D音效使聽者可 從一 3 D音頻系統播放之音效聽出一物體的動作。437253 B7 V. Description of the Invention (1) This application has the priority of the following U.S. patent applications, whose serial number is 60 / 065,855 'The name is "Multipurpose Digital Signal Processing + System" (multipurpose digital signal processing system), application date : November 14, 1997, the contents of which are here directly and for reference. Field of the Invention The present invention relates generally to three-dimensional (3D) sound effects, and more particularly to digital applications for the time delay between hearings used in 3D digital sound effects. BACKGROUND OF THE INVENTION Many high-end consumer devices provide a choice of three-dimensional (3D) sound effects, allowing for a more realistic feel when listening to sound effects. In some applications, 3D sound effects allow listeners to hear the motion of an object from sound effects played by a 3D audio system.
Ata丨及Schroeder早在1962年即建構串音消除器，如美國 專利號3,236,949號’在此併供參考。八1&1-3(：111'〇646130音 效串音消除器爲使用特殊類比放大器及類比濾波器的類比 實例。爲使用兩個喇叭以獲得較佳之音效定位性能，Atal 及Schroeder依據實證加入依賴確定頻率之滤波器。無疑 地’這些複雜的類比裝置不適用於今日之數位音頻技術。 聽覺間時間差異（ITD)即聲波到達兩耳所需時間的差異， 爲3 D音效設計中所使用之重要且主導的參數。該聽覺間 時間差異導致3D音頻或聽覺顯示中兩耳的不一致。尤其 是當一音效物體在一水平平面移動，在該音效物體衝擊一 耳與同一音效物體衝擊另一耳之間，發生連續的聽覺間時 間延遲。使用此ITD而造出聽者所想要之往任何方向移動 的聽覺映像。 -4- 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公f {請先閲讀背面之注意事項再填寫本頁)Ata 丨 and Schroeder built crosstalk cancellers as early as 1962, such as U.S. Patent No. 3,236,949 'and incorporated herein by reference. Eight 1 & 1-3 (: 111'〇646130 audio crosstalk canceller is an example of the use of special analog amplifiers and analog filters. In order to use two speakers to obtain better sound localization performance, Atal and Schroeder added dependence based on the evidence Frequency-determining filters. Undoubtedly, these complex analog devices are not suitable for today's digital audio technology. The time difference between hearings (ITD) is the difference in the time required for sound waves to reach both ears. It is used in 3D sound design. Important and dominant parameter. The time difference between hearing causes the inconsistency of the two ears in 3D audio or auditory display. Especially when a sound effect object moves on a horizontal plane, the sound effect object impacts one ear and the same sound object impacts the other ear. There is a continuous time delay between hearings. Use this ITD to create the auditory image that the listener wants to move in any direction. -4- This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297) Public f (Please read the notes on the back before filling this page)
装--------^訂·--------線I 經濟部智慧財產局員工消費合作社印製 A7 ^37253 *—________— B7___ 五、發明說明（2 ) 藉由適當地延遲至少一耳的聲波，可「欺騙」聽者的耳 朵相信音效是從聽者所想像位置發出的。這通常需要適當 地消除另一耳之原始聲波，並適當地消除前一耳之综合聲 波。Equipment -------- ^ Order · -------- Line I Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 ^ 37253 * —________— B7___ V. Description of the Invention (2) By appropriate Delaying at least one ear's sound waves can "trick" the listener's ear into believing that the sound is emitted from the listener's imagination. This usually requires the proper cancellation of the original sound wave of the other ear and the comprehensive sound wave of the previous ear.
Atal-Schroeder以適當的類比濾波器與類比放大器應用延 遲及消除’如圖5及6所示。圖5，6在Atal-Schroeder美國 專利號3,236,949中詳細説明，在此分別參考圖2及4。在此 圖5顯示習用之3 D音效系統，用以造出來自聽者所想像位 置之音效映像’而圖6在此則顯示Atal- Schroeder所應用之 多個分接點的類比延遲線。 因此’操縱該聽覺間時間延遲以综合特定聲源位置，並 造出特定音效之移動感。 習用3 D音效系統將聽覺間時間差異嵌入實證判定之頭相 關傳輸功能（HRTF)中，其通常藉由在假人頭耳朵植入麥克 風而判定。可得之延遲通常具有以空的濾波器分接點形成 之較大解析度’如Atal-Schroeder所揭露。 然而，習用數位環境中之類比方法的應用有兩個基本問 靖°首先’可得時間延遲之大解析度使聽者所期望之位置 造成不連續取樣的聽覺間時間差異。因此，必須選擇「最 接近」或「最合適」之ITD，其最高可偏離理想參數 50% ^此會導致聽者音效移動感的跳動效應。此外，仿效 如圖ό所示具有多個分接點類比濾波器之數位濾波器的應 用是需要大量計算，因此從計算觀點而言該系統是無效率 的0 ί請先閲讀背面之注意事項再填寫本頁) 表-----I--訂·.---一 — —1線- 經濟部智慧財產局員工消費合作社印製Atal-Schroeder applies delay and cancellation with appropriate analog filters and analog amplifiers' as shown in Figures 5 and 6. Figures 5 and 6 are detailed in Atal-Schroeder U.S. Patent No. 3,236,949, and reference is made here to Figures 2 and 4, respectively. Figure 5 shows a conventional 3D sound system used to create a sound image from the position imagined by the listener '. Figure 6 here shows the analog delay lines of multiple tap points applied by Atal-Schroeder. So 'manipulate the time delay between hearings to synthesize a specific sound source position and create a sense of movement of a specific sound effect. The conventional 3D sound system embeds the temporal difference between hearings into the head-related transmission function (HRTF) of the empirical judgment, which is usually determined by implanting a microphone into the ear of the dummy. The available delay usually has a larger resolution 'formed with empty filter taps, as disclosed by Atal-Schroeder. However, the application of the analog method in the conventional digital environment has two basic problems. First of all, the large resolution of the available time delay makes the position expected by the listener cause discontinuous sampling time difference between hearings. Therefore, it is necessary to choose the "closest" or "most suitable" ITD, which can deviate from the ideal parameter by up to 50% ^ This will cause the sound effect of the listener to move. In addition, the application of a digital filter that emulates an analog filter with multiple tap points as shown in Figure 6 requires a lot of calculations, so from a calculation point of view, the system is inefficient. 0 Please read the precautions on the back first (Fill in this page) Form ----- I--Order · .--- One-- —Line 1-Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs
A7 437253 ------------Β7___ 五、發明說明（3 ) —般常提出之根據固定解析度提供更準確ITD之數位3Ε) 音效系統的應用，爲插入整個HRTF裝置而使ITD亦插入。 不幸地’插入法本身變成需密集計算，而可能在有關數位 3 D音效系統之其他情況下增加而非解決計算的無效性。 因此需要提供數位3D音效有效而簡單的方法及裝置。 發明飨.娃 根據本發明之原則’使用在3 D音頻音效系統中之數位延 遲線’包括提供在第一解析度内選擇任一延遲之第一延遲 模組。第二延遲模組與該第一延遲模組串聯。該第二延遲 模組提供任何額外之複數分數延遲的選擇。各個額外分數 延遲少於該第一解析度。 根據本發明另一概念，用以在數位3 D音效系統中提供聽 覺間時間延遲的方法，包括選擇複數可得第一時間延遲之 一 ’其在各個該複數可得時間延遲間具有一第一解析度。 另外，選擇複數可得第二時間延遲之一。該複數可得第二 時間延遲各少於該第一解析度。將所選擇之第一時間延遲 加上第二時間延遲，而提供所要之聽覺間時間延遲。 附圖簡單説明 配合以下附圖來説明本發明，熟習此技藝者即可更明暸 本發明的目的及優點，其中： 圖1爲一方塊圖，根據本發明原則，顯示包括一數位聽 覺間延遲線的數位3 D音效系統。 圖2爲一更詳細之圖表，根據本發明原則，顯示用以在 一數位環境中創造3D音效之數位3D音效系統。 -6- 紙張尺度適用中國國家標準（CNS)A4規格（21〇 x 297^1------ 1--------1 ----1 ^---------^ I (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 437253 A7 經濟部智慧財產局員工消費合作社印製 Β7 五、發明說明（4 ) 圖3舄根據本發明原則，顯示使用分數延遲減波器共同 觸排之多個數位音頻流的應用圖。 圖4爲根據本發明原則’顯示用以造出—改進之〖το查詢 表的程序，該查詢表適用於如圖1，2顯示之3D音效應用 所使用之ITD查詢表。 圖5顯示一習用3 D音效系統，用以從聽者所想像位置造 出音效映像。 圖ό顯示Atal-Schroeder所應用之具有多個分接點的習用 類比延遲線。 實施例詳細韻明 根據本發明原則，從所量測及實證判定之hrtf抽取出 ITD ’將之校平並應用於一查詢表。藉由一延遲線提供該 ITD的應用，該延遲線包括：提供粗略估計延遲之整數部 分，及提供非常準確延遲之分數部分，並除去聽覺範圍内 之不連續，而提供更舒適的聆聽環境。 本發明提供一數位濾波器觸排，具有一簡單而低成本之 結構，用以執行穩定的_音消除，提供實際音效映像的良 好定位及具體化。 根據本發明原則，記錄並使用對應於味I w八位置之頭相關 傳輸功能，以構成該濾波器係數。研究該喇p八位置與渡波 器設計間的關係，而提供更舒適的聆聽環境，最佳化其 3 D音效效應。因此，聽者不須坐在十分準確地相對於响 八而定位的位置，而可欣賞僅藉由兩個味j α八表現音頻的 3 D概念。 本紙張又度適用中國國家標準（CNS)A4規格（210 X 297公釐） f靖先閱讀背面之注意事項再填寫本頁) 裝·------ -訂----1----線 437253 A7 ---— B/_ ___ 五、發明說明（5 ) 圖1爲一方塊圖，根據本發明原則，顯示所揭露之數位 3 D音效系統實施例之基本組件，該數位3 d音效系統包括 一數位聽覺間延遲線。 特別將一音效源220輸入一數位聽覺間時間延遲線254。 該聽覺間延遲線254包括：一整數延遲模組250，提供所需 要之聽覺間時間延遲之粗略估計，以及一分數延遲模组 252 ’提供極精細的額外時間延遲。在揭露之實施例中， 從複數預設延遲間，選擇該整數延遲模組25〇及分數延遲 模組252兩者之特定配置，大幅減少或消除在其他情況下 插入一特定聽覺間時間延遲所需之密集運算。 藉由一定位控制模組270，提供與左（或右）耳信號26〇與 右（或左）耳信號262有關並提供所需音效映像定位的特定 延遲。 圖2爲圖1所顯示之數位3 d音效系統更詳細的圖表。 所揭露實施例之整數延遲模組250尤其包括一先入先出 (FIFO)緩衝器204。該FIFO緩衝器204對應該數位音頻樣本 而可爲任何適合的寬度，如〗6位元。此外，該FIFO緩衝 器204的長度是根據應用所期望之3 d音效映像所需之最大 延遲。該特定延遲與將該特定數位音頻樣本輸入該FIF〇緩 衝器204後所選擇之時脈週期有關。此一整數延遲時間的 選擇在圖2中以多工開關206代表。任一特定數位音頻樣本 224a-224d均串聯饋入該FIFO緩衝器204，而各樣本224a- 224d代表分接點數。 該FIFO緩衝器204之時脈週期大於取樣頻率。因此，模 -8- 297公釐） (諝先閱讀背面之注意事項再填寫本頁) 裝--------訂·--------線· 經濟部智慧財產局員工消費合作社印製 43 7253 經濟部智慧財產局員工消貲合作社印製 A7 B7 五、發明說明（6 ) 範取樣頻率2 2千赫’則該整數延遲模組2 5 〇之「整數」部 分或解析度爲1/22,000或近似4 5微秒（uS)。 該數位聽覺間延遲線254以一分數延遲模組提供一更爲 精細的「分數」延遲。此一分數延遲是藉由選擇任一複數 分數延遲濾波器208-2 12而提供的。 分數延遲模組252以比整數延遲模組25〇更精細的解析 度’有效地製造一可校正延遲。分數延遲2〇8_212各爲所 謂的可變相位濾波器’對應於所需之分數延遲而具有可變 相位位移。該相位數量（即分數延遲濾波器2〇8_212)藉由人 聆聽之行爲測驗而實證地判定。 所揭露實施例中’使用6 4個分數延遲濾波器，其各在適 合應用之精細解析增量中提供遞增的延遲。舉例來説，在 示範抽樣頻率爲2 2千赫時，該分數延遲濾波器20.8-2 12之 間的解析度爲（45 uS)/64，或是約0.7 uS的解析度。此特別 精細的解析度（以及由整數延遲模組250所提供之粗略估計 解析度）’可根據特定之應用所需而加以校正。 分數延遲滤波器208-212各爲無限脈·衝回應（Fir);慮波 器’即多相濾波器’影響所需之延遲。各個分數延遲遽波 器208-212 ’及/分數延遲控制開關216及/或多工器214，皆 可根據本發明原則應用於任一適合的處理器中，如數位信 號處理器（DSP)，微處理器，或微控制器。 在使用2 2千赫抽樣頻率之示範實施例中，該第一分數延 遲遽波器2 0 8提供〇 · 7 S之延遲給通過該處之數位音頻樣 本，第二分數延遲濾波器2 1〇提供近似1.4 uS之延遲等等， -9- 本紙張尺度適用中國國家標準（CNS)A4規樁（210 X 297公釐） ---^-------—* 訂·--------線. (請先閲讀背面之注意事項再4寫本頁> 43 7253 經濟部智慧財產局員工消費合作社印製 A7 B7 五、發明說明（7 ) 直到提供近似44.3 11S延遲的最後分數延遲濾波器212。 藉由在分數延遲模組252中之多工器214，應用適當分數 延遲濾波器208-212選擇。所顯示之實施例中，在一處理 器（如數位信號處理器）中應用各分數延遲濾波器208-212， 而最好在前端從該分數延遲濾波器208-212中做一適當選 擇’以避免執行在該特定音頻樣本中不會使用之分數延遲 濾波器208-2 12而浪費計算功率。 該聽覺間時間延遲藉由定位控制模组270控制，其包括 一 3 D音頻應用源位置控制器222，一聽覺間時間延遲（itd) 查詢表220，及一整數及分數延遲選擇器218。在揭露之實 施例中，將該定位控制模組270應用於一合適之處理器， 如微處理器，微控制器’或數位信號處理器（DSpp當 然，該定位控制模组2 7 0亦可部分地或全部地應用於硬體 中，如使用可程式陣列邏輯。 該3 D音頻應用源位置控制器222選擇當時輸入該數位聽 覺間延遲線254之音效樣本的所需「想像」位置。相對於 一參考點’如聽者頭部，該所需位置可具有所需之χ，^及 z座標。根據所需位置，在ITD查詢表220中判定一相關 ITD。該整數及分數延遲選擇器判定在整數延遲模組25〇之 解析度内不超過所需ITD而能獲得之最大整數値，並適當 地控制該整數延遲模組2 5 0，以將該所需延遲提供給該音 頻樣本。同樣地，藉由從分數延遲模组252中可得之分數 延遲濾波器208-2 12適當選擇所需要者，而提供該整數延 遲模組250所未提供之所需ITD剩餘或分數部分。 -10- 本紙張尺度適用t國國家標準（CNS)A4規格（210 X 297公釐） ^—l — f — i^.i——-----線- ί靖先閱讀背面之注意事項再填寫本頁) A7 B7 43々53 五、發明說明（8 ) 圖3顯示根據本發明原則使用分數延遲濾波器共同觸排 之多數位音頻流的應用圖。因此，藉由用於同一聽者之複 數音頻源’可使用複數分數延遲濾波器208-2 12，而不需 爲各個音頻源複製該分數延遲模组252。 围4顯示造出圖2所示之ITD查詢表220之程序。 在步驟102中’特別將一聲源置於環繞聆聽環境之不同 位置，如沿著該聲源周圍球面之增量點，而實際地量測兩 耳脈衝反應。 步驟104中’從步驟102所獲得之實際量測資訊中抽取出 ITD資訊’而判定該球面上各適當點ITD値之「網絡」。該 I T D樣本尤其可從使用互相關量測之左-右耳頭相關傳輸 功能（HRTF)而取得。這些樣本可視爲方位及高度座標之連 續ITD功能之不連續樣本。 步驟106中，爲避免給聽者「跳動」或其他不需要之效 應，使用任一適當之校平算法校平步驟1 〇4中所判定之ITD 網絡°舉例來説’該ITD樣本可使用「一般的齒條模型」 加以规律化，或藉由·—維滤波益加以適當地滤波及插入而 獲得平順及連續。由於此校平可爲密集計算，而僅離線地 執行一次，且不在接收數位音頻樣本之即時執行。 步驟108中’將該已校平之ITD網絡輸入ITD查詢表22〇 d 該ITD網絡可使用任一座標系統，如球面座標或標準X， 及z座標系統。 在揭露之實施例中，判定整體延遲之最精細解析度最好 少於1微秒（uS) ’以使該音效流所導致的任何不連續低於 -11 - 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公爱） (請先閱讀背面之注意事項再填寫本頁) 戚------ 訂---------線 經濟部智慧財產局員工消費合作社印f 37253 --------B7 五、發明說明（9 ) —般人類之聆聽門檻，其中該整體延遲即是藉由整數延遲 模组250及分數延遲模組252所提供延遲之結合。在高拙樣 頻率的情況下’最好用較快時間的解析。例如，一音頻流 抽樣頻率22,05千赫時，使用6 4相多相濾波器以在時間延 遲中獲得次微秒解析度。另一例中，使用一 6 〇相多相滅波 器以提供所需之時間延遲’而合適地表現在48千赫抽樣之 音頻流。 由於所揭露實施例中之分數延遲濾波器208-212各爲 FIR(多相）濾波器，可將本發明原則同樣地應用於其他在 數位音頻樣本中提供所需延遲的濾波器或數位延遲。 根據本發明原則之數位聽覺間延遲線254可應用在任一 合適的處理器或電腦系統中。舉例來説，該數位聽覺間延 遲線254可應用於使用正式指令裝置或MMX™技術之個人 電腦（PC)平台的主機層，或可應用於數位信號處理器（DSP) 中。 根據本發明原則，爲進一步改進效率，可根據所需之來 源音效移動，將延遲固定給一耳，而改變給另一耳之音 效。此不同方法比起處理兩耳不同延遲音效，可節省最多 一半的指令週期。 可使已適當延遲之左右耳信號前進另一級以更進一步處 理，或直接傳送至頭戴耳機或喇叭而呈現給聽者，如簡單 的兩耳信號處理方法。 因此，根據本發明原則，只需用梢微處理的延遲’即可 解決在3 D音頻產生適當聽覺間時間延遲及聽覺實際顯示 -12- 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閱讀背面之注意事項再填寫本頁) 装--------訂---------線· 經濟部智慧財產局員工消費合作社印製 43?253 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（1〇 ) 應用的問題。本發明原則比習用插入技術更能節省處理器 I指令週期’而使用FIFO緩衝器204可不需儲存合適的複 數空分接點’其爲其他情況下各個習用HRTF濾波器所需 的。所省下之處理功率可用於其他用途，如加強hRTF效 應。 由於ITD被抽取出，處理，並分別應用於粗略解析的延 遲模组（即整數延遲模組250)及細調的延遲模組（即分數延 遲模組252)中，可輕易地控制並校正該3D音頻效應以配 合其他需要，如最佳化以供不同的頭部尺寸。根據本發明 原則，以超解析度次樣本濾波多相濾波器爲主的延遲線， 在呈現給聽者時，僅傳導所需之延遲而不會不連續傳導戋 傳出「喀嚒」聲。 本發明之原則可應用於任一3D音頻系統，其使用一聽覺 間時間延遲做爲聽者聽出之音效方向的定位行列。舉例來 説，本發明有關於定位於聚集，具體化多喇叭陣列系統的 3 D音效，該陣列系統具有兩個在AC3/D〇lbyTM數位系統中 之物理性喇叭，先進的電腦使用者介面，用於建構性預排 的有效聽覺眞實性軟體，聽覺化軟/硬體，用於—般立體 聲及無線頭戴耳機之3D增強等。 以上已參考示範實施例説明本發明，在不悖離本發明實 際精神及範圍下，熟習此技藝者可針對本發明所述之實施 例做不同改進。 ' -13- 本纸張尺度_中_家標準（CNS)A4現格⑵Q x视公爱）A7 437253 ------------ B7___ V. Description of the invention (3)-Digital 3E that is often proposed to provide a more accurate ITD based on a fixed resolution) The application of a sound effect system is for inserting the entire HRTF device. Make ITD also inserted. Unfortunately, the 'insert method' itself becomes computationally intensive, and may increase rather than address the computational inefficiency in other situations related to digital 3D sound systems. Therefore, it is necessary to provide an effective and simple method and device for digital 3D sound effects. Invention 娃. Baby According to the principle of the present invention 'digital delay line used in 3D audio sound system' includes a first delay module which provides selection of any delay within a first resolution. A second delay module is connected in series with the first delay module. The second delay module provides the option of any additional plural fractional delay. Each additional fractional delay is less than the first resolution. According to another concept of the present invention, a method for providing an auditory time delay in a digital 3D sound system includes selecting one of a plurality of first time delays obtainable from a plurality of time delays. Resolution. In addition, selecting the complex number yields one of the second time delays. The plural numbers can be obtained that the second time delays are each less than the first resolution. The selected first time delay is added to the second time delay to provide the desired inter-auditory time delay. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be explained with the following drawings. Those skilled in the art will better understand the objects and advantages of the invention. Among them: FIG. 1 is a block diagram showing a digital inter-auditory delay line according to the principles of the invention. Digital 3D sound system. Fig. 2 is a more detailed diagram showing a digital 3D sound system for creating 3D sound effects in a digital environment according to the principles of the present invention. -6- Paper size applies to China National Standard (CNS) A4 specification (21〇x 297 ^ 1 ------ 1 -------- 1 ---- 1 ^ ------- -^ I (Please read the notes on the back before filling this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 437253 A7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economics B7 V. Description of the invention (4) Figure 3 舄In accordance with the principles of the present invention, an application diagram showing multiple digital audio streams that are collectively touched using a fractional delay canceller is shown. Figure 4 is a program that shows a query table created and improved according to the principles of the present invention. The query The table is suitable for the ITD look-up table used for the 3D sound effects shown in Figures 1 and 2. Figure 5 shows a conventional 3D sound effect system for creating a sound image from the position imagined by the listener. A conventional analog delay line with multiple tap points is used. Detailed description of the embodiment According to the principles of the present invention, ITD is extracted from the measured and empirically determined hrtf and leveled and applied to a lookup table. By A delay line provides the application of the ITD, the delay line includes: providing a rough estimate of the delay The digital part, and the fraction part that provides a very accurate delay, removes discontinuities in the hearing range, and provides a more comfortable listening environment. The present invention provides a digital filter touch pad with a simple and low-cost structure for Perform stable sound cancellation, provide good localization and concreteness of actual sound image. According to the principles of the present invention, record and use the head-related transmission function corresponding to the eight positions of taste I w to form the filter coefficient. The relationship between the eight-position and the design of the ferrule provides a more comfortable listening environment and optimizes its 3D sound effect. Therefore, the listener does not need to sit in a position that is positioned relatively accurately with respect to the loud eight, but can enjoy Only the 3D concept of audio is expressed by two flavors. This paper is again applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm). F Jing first read the precautions on the back before filling in this page). · ------ -Order ---- 1 ---- line 437253 A7 ----- B / _ ___ V. Description of the invention (5) Figure 1 is a block diagram showing the Exposed Digital 3D Sound System Example The basic components of the digital audio system comprising 3 d between a digital delay line audible. In particular, a sound source 220 is input to a digital inter-auditory time delay line 254. The inter-auditory delay line 254 includes an integer delay module 250, which provides a rough estimate of the required inter-auditory time delay, and a fractional delay module 252 ', which provides extremely fine extra time delay. In the disclosed embodiment, a specific configuration of the integer delay module 250 and the fractional delay module 252 is selected from a plurality of preset delay intervals, which greatly reduces or eliminates the insertion of a specific auditory time delay in other cases. Need intensive operations. Through a positioning control module 270, a specific delay related to the left (or right) ear signal 26 and the right (or left) ear signal 262 is provided and a desired sound image localization is provided. Figure 2 is a more detailed diagram of the digital 3D sound system shown in Figure 1. The integer delay module 250 of the disclosed embodiment includes a first-in-first-out (FIFO) buffer 204. The FIFO buffer 204 may correspond to digital audio samples and may have any suitable width, such as 6 bits. In addition, the length of the FIFO buffer 204 is based on the maximum delay required by the application for the 3 d audio image. The specific delay is related to a selected clock period after the specific digital audio sample is input into the FIF buffer 204. The selection of this integer delay time is represented by the multiplexer switch 206 in FIG. Any specific digital audio samples 224a-224d are fed into the FIFO buffer 204 in series, and each sample 224a-224d represents the number of tap points. The clock period of the FIFO buffer 204 is greater than the sampling frequency. Therefore, the mold-8-297 mm) (谞 Please read the notes on the back before filling in this page). Printed by the consumer cooperative 43 7253 Printed by the staff of the Intellectual Property Bureau of the Ministry of Economy A7 B7 Printed by the cooperative V. Description of the invention (6) If the sampling frequency is 2 2 kHz, the “integer” part of the integer delay module 2 5 0 or analysis The degree is 1 / 22,000 or approximately 45 microseconds (uS). The digital interaural delay line 254 provides a finer "fractional" delay with a fractional delay module. This fractional delay is provided by selecting any of the complex fractional delay filters 208-2 12. The fractional delay module 252 efficiently produces a correctable delay with a finer resolution 'than the integer delay module 25. Each of the fractional delays 208_212 is a so-called variable phase filter 'which has a variable phase shift corresponding to a required fractional delay. The number of phases (ie, the fractional delay filter 208_212) is empirically determined by a behavioral test of human listening. In the disclosed embodiment ', 64 fractional delay filters are used, each of which provides an incremental delay in a fine resolution increment suitable for the application. For example, at a sample frequency of 2 2 kHz, the resolution between the fractional delay filters 20.8-2 12 is (45 uS) / 64, or a resolution of about 0.7 uS. This particularly fine resolution (and the rough estimated resolution provided by the integer delay module 250) 'can be corrected as needed for a particular application. The fractional delay filters 208-212 are each infinite pulse impulse response (Fir); the delay required to consider the effect of the wave filter 'i.e. the polyphase filter'. Each of the fractional delay chirpers 208-212 'and / or the fractional delay control switch 216 and / or the multiplexer 214 can be applied to any suitable processor, such as a digital signal processor (DSP), according to the principles of the present invention. Microprocessor, or microcontroller. In an exemplary embodiment using a sampling frequency of 22 kHz, the first fractional delay waver 208 provides a delay of 0.7 S to the digital audio samples passing there, and the second fractional delay filter 2 1 Provides a delay of approximately 1.4 uS, etc., -9- This paper size applies to China National Standard (CNS) A4 gauge pile (210 X 297 mm) --- ^ --------- * Order · --- ----- line. (Please read the precautions on the back and then write this page> 43 7253 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Description (7) Until the approximately 44.3 11S delay is provided Finally, the fractional delay filter 212. By using the multiplexer 214 in the fractional delay module 252, the appropriate fractional delay filter 208-212 is selected. In the embodiment shown, a processor such as a digital signal processor ), Each fractional delay filter 208-212 is applied, and it is best to make an appropriate selection from the fractional delay filter 208-212 at the front end to avoid performing the fractional delay filter 208 that will not be used in this particular audio sample. -2 12 and wasted computing power. The time delay between hearings is controlled by positioning Module 270 controls, which includes a 3D audio application source position controller 222, an inter-auditory time delay (itd) lookup table 220, and an integer and fractional delay selector 218. In the disclosed embodiment, the positioning The control module 270 is applied to a suitable processor, such as a microprocessor, a microcontroller, or a digital signal processor (DSpp. Of course, the positioning control module 270 can also be partially or fully applied to hardware. For example, using programmable array logic. The 3D audio application source position controller 222 selects the desired "imaginary" position of the audio sample of the digital inter-aural delay line 254 at that time. Relative to a reference point, such as the listener's head The required position may have the required χ, ^, and z coordinates. According to the required position, a related ITD is determined in the ITD lookup table 220. The integer and fractional delay selector determines the resolution in the integer delay module 25. The maximum integer 値 that can be obtained within the required ITD is not exceeded, and the integer delay module 2 50 is appropriately controlled to provide the required delay to the audio sample. Similarly, by using the fractional delay module 252 The obtained fractional delay filter 208-2 12 appropriately selects the required ones, and provides the remaining or fractional part of the required ITD which is not provided by the integer delay module 250. -10- This paper standard is applicable to National Standards (CNS) A4 Specifications (210 X 297 mm) ^ —l — f — i ^ .i ——----- line-ί Jing first read the notes on the back before filling out this page) A7 B7 43々53 V. Description of the invention (8) FIG. 3 shows an application diagram of a majority-bit audio stream commonly touched using a fractional delay filter in accordance with the principles of the present invention. Therefore, the complex fractional delay filter 208-2 12 can be used by a plurality of audio sources' for the same listener, without having to duplicate the fractional delay module 252 for each audio source. Figure 4 shows the procedure for creating the ITD lookup table 220 shown in FIG. In step 102 ', a sound source is specifically placed at different positions around the listening environment, such as incremental points along the spherical surface around the sound source, and the ear ear pulse response is actually measured. In step 104, "the ITD information is extracted from the actual measurement information obtained in step 102", and the "network" of each appropriate point ITD on the sphere is determined. The I T D sample can be obtained in particular from the left-to-right ear-correlation transfer function (HRTF) using cross-correlation measurements. These samples can be considered as discontinuous samples of continuous ITD functions for azimuth and altitude coordinates. In step 106, in order to avoid "jumping" or other unwanted effects to the listener, use any appropriate leveling algorithm to level the ITD network determined in step 104. For example, 'The ITD sample can use " "General rack model" can be regularized, or smoothed and continuous by proper filtering and insertion through dimensional filtering benefits. Because this leveling can be computationally intensive, it is performed only once offline, and not immediately when receiving digital audio samples. In step 108, the leveled ITD network is entered into the ITD lookup table 22 d. The ITD network may use any coordinate system, such as a spherical coordinate or a standard X, and a z coordinate system. In the disclosed embodiment, it is better to determine the finest resolution of the overall delay to be less than 1 microsecond (uS) 'so that any discontinuity caused by the audio stream is lower than -11-this paper size applies Chinese national standards ( CNS) A4 specification (210 X 297 public love) (Please read the precautions on the back before filling this page) Qi -------- Order --------- Consumer Consumption Cooperative of Intellectual Property Bureau, Ministry of Economic Affairs Print f 37253 -------- B7 V. Description of the invention (9)-The threshold of human listening, in which the overall delay is a combination of the delay provided by the integer delay module 250 and the fractional delay module 252 . In the case of a high sample frequency, it is better to use a faster analysis time. For example, at an audio stream sampling frequency of 22,05 kHz, a 6 4-phase polyphase filter is used to obtain sub-microsecond resolution in the time delay. In another example, a 60-phase polyphase annihilator is used to provide the required time delay ' and to appropriately represent an audio stream sampled at 48 kHz. Since the fractional delay filters 208-212 in the disclosed embodiments are each FIR (polyphase) filters, the principles of the present invention can be similarly applied to other filters or digital delays that provide the required delay in digital audio samples. The digital inter-auditory delay line 254 according to the principles of the present invention may be applied to any suitable processor or computer system. For example, the digital auditory delay line 254 can be applied to the host layer of a personal computer (PC) platform using a formal command device or MMX ™ technology, or it can be applied to a digital signal processor (DSP). According to the principles of the present invention, in order to further improve the efficiency, the delay can be fixed to one ear and changed to the other ear's sound effect according to the required source sound effect movement. This different method saves up to half of the instruction cycles compared to processing different delay sounds in both ears. The left and right ear signals, which have been appropriately delayed, can be advanced to another stage for further processing, or directly transmitted to headphones or speakers for presentation to the listener, such as a simple binaural signal processing method. Therefore, according to the principles of the present invention, only the delay of the micro-processing is needed to solve the time delay and the actual display of hearing between 3D audio generation. -12- This paper standard is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) (Please read the precautions on the back before filling out this page) Packing -------- Ordering -------- Line Printed by Employee Consumption Cooperative of Intellectual Property Bureau, Ministry of Economic Affairs 43 253 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the invention (1) Application issues. The principle of the present invention can save the processor I instruction cycle more than the conventional insertion technology, and the use of the FIFO buffer 204 does not need to store a suitable complex space tapping point, which is required by other conventional HRTF filters in other cases. The saved processing power can be used for other purposes, such as enhancing hRTF effect. Since the ITD is extracted, processed, and applied to the rough analysis delay module (that is, the integer delay module 250) and the fine-tuned delay module (that is, the fractional delay module 252), it can be easily controlled and corrected. 3D audio effects to meet other needs, such as optimization for different head sizes. According to the principles of the present invention, a delay line mainly composed of a super-resolution sub-sample filtering polyphase filter, when presented to a listener, conducts only the required delay without discontinuous conduction. A "click" sound is emitted. The principle of the present invention can be applied to any 3D audio system, which uses an inter-auditory time delay as the positioning sequence of the sound effect direction heard by the listener. For example, the present invention relates to the 3D sound effect of a multi-speaker array system positioned in a cluster, which has two physical speakers in an AC3 / DolbyTM digital system, an advanced computer user interface, Effective auditory solid software for constructive walkthrough, auditory software / hardware, for general stereo and 3D enhancement of wireless headphones, etc. The present invention has been described above with reference to the exemplary embodiments. Without departing from the actual spirit and scope of the present invention, those skilled in the art can make different improvements to the embodiments described in the present invention. '-13- This paper size _ Medium _ Home Standard (CNS) A4 is now Q x Q as public love)
Iilllt — ιί — — — 褒 I I I I I I I 訂-------I 1 - (請先閱讀背面之注意事項再填寫本頁)Iilllt — ιί — — — 褒 I I I I I I I Order ------- I 1-(Please read the notes on the back before filling in this page)