200930090 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種影像分配器，特別是關於一種具有 視訊補償功能的影像分配器。 【先前技術】 近年來，影像分配器(Video splitter)的應甩愈來愈普 〇 及’可應用於商場的宣傳廣播、公司、學校的簡報設備... 或其他商業用途。影像分配器是一種影音分享設備，由單 —輸入來源接收視訊與音訊訊號，並經過複製與增強後， 輸出至複數台顯示裝置，其中顯示裝置可包括顯示器、投 影機...等。 請參照圖一，其係為習知影像分配系統示意圖。如圖 所示’影像分配系統至少包括一電腦主機10、一影像分配 器12、複數台顯示裝置13及複數條傳輸線14。其中，此 〇 影像分配器丨2具有一個輸入端122及複數個輸出端124。 每一傳輸線14的兩端可分別連接到影像分配器12的輸出 端124及顯示裝置13，而成為影像分配器12與顯示裝置 13間的傳輸通道。 電腦主機10係為視訊與音訊訊號的提供者 ，可將視訊 與音訊訊號傳送到影像分配器12。在較佳實施例中，電腦 主機1G係藉由-傳輸鱗接至影像分配^ 12的輸入端 122 ’上述訊號便可藉由此傳輸線傳送至影像分配器12。 影像分配器12接收視訊與音訊訊號後，便進行訊號的 200930090 複製與增強…等程序，然後將其透過每一條傳輸線Μ傳送 到各個顯示裝置13。 由於場地需求的關係，影像分配器12與顯示裝置a 間的距離可能會相隔很遠’視訊與音訊訊號便需透過很長 的傳輸線14去傳送訊號。然而，當所經傳輸線14長度愈 長時，視訊訊號的衰減程度愈明顯。 請參照圖二Α及圖二Β，其係分別為影像分配系統之 電腦主機10所輸出之視訊訊號示意圖，以及習知影像分配 系統之顯示裝置13所接收到之視訊訊號示意圖。如圖所 示，經過傳輸線長距離的傳輸後，視訊訊號會產生明顯地 衰減。此時，顯示裝置13所播放出來的影像就會產生失 真、拖影及色彩不飽和…等現象，而嚴重影響影像品質。 習知技術係以CAT5纜線及差動傳輸之方式延伸電腦 主機與顯示裝置間之距離，請參照中華民國專利〖243890 , 此專利的線長量測裝置係在傳輸線之一端(影像訊號來源) 設置-訊號合成電路，另—端(影像接收端博置一訊號轉 換電路及線長計算電路。此專利藉由裝設在影像接收端之 -線長計算電路量測衰減量計算出傳輸線的長度，並依據 ^:測結果’使用-色彩訊號補償電路補償衰減的視訊訊 號。在-視頻訊號之-垂直同步訊號有效時，訊號合成電 路將-電子峨4加至傳輸線之彡對子線之—。訊號轉換 電路將經線傳輸後之該冑子訊讎滅一數值， 線長計算電路便根據該數值計算丨該傳輸線的長度。 然而’上述專利必須在傳輸線的兩端分別設置線長量 測裝置及訊號合成電路，在實際翻上成本較高。 200930090 如何改善顯示裝置所播放出來的影像品質，J *、用的便利性’實為當前技術所必須解決的問題 【發明内容】 ，本發^之―目的係在於，對讀輸·麟會造成的 訊號她預先做—補償，使顯示裝置的影像不會有失 真或拖影的現象。200930090 IX. Description of the Invention: [Technical Field] The present invention relates to an image distributor, and more particularly to an image distributor having a video compensation function. [Prior Art] In recent years, video splitters have become more and more popular and can be applied to promotional broadcasts in stores, companies, school briefing devices, or other commercial uses. The image distributor is an audio-visual sharing device that receives video and audio signals from a single-input source, and after being copied and enhanced, outputs to a plurality of display devices, wherein the display device can include a display, a projector, and the like. Please refer to FIG. 1 , which is a schematic diagram of a conventional image distribution system. As shown in the figure, the image distribution system includes at least a computer main unit 10, an image distributor 12, a plurality of display devices 13, and a plurality of transmission lines 14. The image distributor 丨2 has an input terminal 122 and a plurality of output terminals 124. Both ends of each transmission line 14 can be respectively connected to the output end 124 of the image distributor 12 and the display device 13, and become a transmission channel between the image distributor 12 and the display device 13. The host computer 10 is a provider of video and audio signals, and can transmit video and audio signals to the image distributor 12. In the preferred embodiment, the computer host 1G is coupled to the image distributor 12 by the transmission line by means of a transmission scale connected to the input 122 of the image distribution unit. After receiving the video and audio signals, the image distributor 12 performs a process such as copying and enhancing the signal of 200930090, and then transmits it to each display device 13 through each of the transmission lines. Due to the demand of the venue, the distance between the image distributor 12 and the display device a may be far apart. The video and audio signals need to be transmitted through the long transmission line 14. However, as the length of the transmission line 14 is longer, the degree of attenuation of the video signal becomes more pronounced. Please refer to FIG. 2 and FIG. 2 respectively, which are respectively a schematic diagram of the video signal outputted by the computer host 10 of the image distribution system, and a schematic diagram of the video signal received by the display device 13 of the conventional image distribution system. As shown in the figure, after a long distance transmission of the transmission line, the video signal will be significantly attenuated. At this time, the image played by the display device 13 will cause distortion, smear, and color saturation, etc., which seriously affect the image quality. The conventional technology extends the distance between the host computer and the display device by means of CAT5 cable and differential transmission. Please refer to the Republic of China patent 〖 243890. The line length measurement device of this patent is at one end of the transmission line (source of image signal). Setting-signal synthesis circuit, the other end (the image receiving end is configured with a signal conversion circuit and a line length calculation circuit. This patent calculates the length of the transmission line by measuring the attenuation amount of the line length calculation circuit installed at the image receiving end. And according to the ^: test result 'use-color signal compensation circuit to compensate the attenuated video signal. When the - video signal - vertical sync signal is valid, the signal synthesizing circuit will add - the electronic 峨 4 to the 彡 pair of the transmission line - The signal conversion circuit annihilates the dice signal after the warp transmission, and the line length calculation circuit calculates the length of the transmission line according to the value. However, the above patent must set the line length measurement at both ends of the transmission line. Device and signal synthesis circuit, the actual cost of turning over is high. 200930090 How to improve the image quality played by the display device, J *, convenience The problem that must be solved by the current technology [invention], the purpose of this is to compensate for the signal caused by reading and losing Lin, so that the image of the display device will not be distorted or smeared. The phenomenon.
❹ 本發明提供—種具視訊補償功能的影像分配器，用以 藉由傳輸線之-連接器將一主機之視訊訊號提供到至少 一顯示裝置。 影像分配器包括至少—輸出端、—信號產生器及一補 償裝置。輸出端係用來連接傳輸線。信號產生器可發送一 測試信號至傳輸線。補償裝置可根據測試信號經由第一傳 輸路徑或第二傳輸路徑的往返時間來補償上述視訊訊號。 其中’第一傳輸路徑係指測試信號經由連接器之一空 腳位(unusedpin)反射後回傳之路徑；第二傳輸路徑係指連 接器之任兩腳位接通形成迴路時，測試信號經由其中一腳 位回傳之路徑。 本發明提供一種線長偵測及視訊補償方法，適用於一 影像分配器將一主機之視訊訊號提供到至少一顯示裝置的 系統，且影像分配器係藉由一傳輸線之一連接器連接至顯 示裝置，此視訊補償方法包含下列步驟： 經由傳輸線傳送一測試信號至連接器之一空腳位 (unused pin)； 8 200930090 接收返回之測試信號； 計算測試信號的往返時間； 依據上述往返_，提供—控制訊號 :以及 ，並將赃後之視訊訊號 傳送到顯示裝置。 本發明提供一種視訊補償方法，適用於一影像分配器 將一主機之視訊訊號提供到至少一顯示裝置的系統，且影 像分配器係藉由一傳輸線將上述視訊訊號傳輸至顯示裝 置，此視訊補償方法包含下列步驟： 將傳輸線之一第一連接器連接至影像分配器，另一端 之一第二連接器則浮置； 接通第二連接器之任兩腳位，以形成一迴路； 經由傳輸線傳送一測試信號至上述迴路； 接收返回之測試信號； 計算測試信號的往返時間； 根據上述往返時間，提供一控制訊號； 將第二連接器連接至顯示裝置；以及 依據控制訊號調整視訊訊號，並將調整後之視訊訊號 傳送到顯示裝置。 關於本發明之優點與精神，以及更詳細的實施方式可 以藉由以下的實施方式以及所附圖式得到進一步的暸解。 200930090 【實施方式】 如先前技術所述’當連接於影像分配器12與顯示裝置 • 13間的傳輸線長度愈長時，顯示裝置13所接收到的視訊 訊號的衰減愈為嚴重。由此可見，視訊訊號的衰減程度與 傳輸線長度成正相關。 因此，本發明之技術内容係包括先測得傳輸線長度， 再根據所測之傳輸線長度預先對影像分配器所輸出的視訊 訊號作補償。也就是說，本發明之影像分配器除了用以將 ❹ 一主機之視訊訊號提供到至少一顯示裝置外，同時具有視 訊補償功能’可對傳輸線長度所會造成的視訊訊號衰減進 行補償。其巾，本剌所权域脑可提供視訊訊號之 主機，例如：電腦主機、DVD播放機..等。 請參照圖三及_，其係分麟本發·彡像分配器執 行補償功能之兩種實施例之示意圖。如圖所示，影像分配 器22包括至少一輸出端224、一信號產生器mi及一補償 裝置23。輸出端224係用來連接一傳輸線24，傳輸線以 ❹ 的兩端分別具有一第一連接器241與一第二連接器242， 而第一連接器241連接到影像分配器22的輸出第 二連接_输《峨13。肢， 為影像分配H 22 _示裝置13間視訊職轉輸通道。 在較佳實施例中，此傳輸線24兩端之第一連接器241與第 二連接器242係為DB15連接器。 上述之信號產生器221可發送一測試信號至傳輸線 24。補償裝置23則可根據職信舰由—第—傳輸路徑或 一第二傳輸路捏的往返時間來推算出傳輸線24之長度，進 200930090 訊訊號;或者是，補償裝置23 的，間補傳輸路徑或該第二傳輪路徑 其中，第-傳輸路捏係指測試信號經由第二連接器 ❹ 之一空腳位(unusedpin)2421反射後回傳之路徑，如圖 第二傳輸路徑係指第二連接器242之任兩腳位 、2423接通形成迴路時，測試信號經由上述其中一腳 位回傳之_。在較佳實闕t上箱卿t 2422、2423 之導通係可用-跳邮之綱導體元件來進行。 補償装置23更包含一控制單元⑽⑽C(mi1io1融， MCU)231及一補償電路232。控制單元231可用來接收由 第-路徑或第二路徑回傳之測試信號，判斷測試信號的往 返時間’並根據往返時間提供一控制訊號，以控制補償電 路232對此視訊訊號進行補償。在較佳實施例中，此控制 訊號可根據測試信號的往返時間對照至一表單233而得 到，或是依據一查表電路(lookup table)所取得的一補償參 數。此控制訊號可使補償電路232產生一補償訊號。 補償電路232則是依據上述控制訊號來調整發送至顯 示裝置13的視訊訊號。在本實施例中，補償電路232係依 據控制訊號來調整一電容值，進而提供補償訊號至視訊訊 號。視訊訊號至少包括R、G及B三訊號，這三個訊號被 傳送至顯示裝置13之前，會先經過補償電路232，並加入 (疊加)補償訊號後’再予傳送到顯示裝置13。 請參照圖五，其係為本發明影像分配器22所輸出之具 有補償訊號之視訊訊號示意圖。承上所述，當視訊訊號加 200930090 ^補償魏時’便會呈現類似圖五之訊號娜。接著，上 述ί有簡峨之視tiU峨經轉輸線24的傳輸後，會產 生衰減S後’顯不襄置13所接收到的視訊訊號型態則恰The present invention provides an image distributor having a video compensation function for providing a video signal of a host to at least one display device via a connector of a transmission line. The image distributor includes at least an output, a signal generator and a compensation device. The output is used to connect the transmission line. The signal generator can send a test signal to the transmission line. The compensating means can compensate the video signal according to the round trip time of the test signal via the first transmission path or the second transmission path. Wherein the first transmission path refers to a path in which the test signal is reflected back through an unused pin of the connector; the second transmission path is when the two pins of the connector are turned on to form a loop, and the test signal passes through the test signal. The path of a foot return. The invention provides a line length detection and video compensation method, which is suitable for a video distributor to provide a video signal of a host to at least one display device, and the image distributor is connected to the display by a connector of a transmission line. The device, the video compensation method comprises the following steps: transmitting a test signal to an unpinned pin of the connector via the transmission line; 8 200930090 receiving the returned test signal; calculating a round trip time of the test signal; according to the round trip _, providing - The control signal: and, and the subsequent video signal is transmitted to the display device. The present invention provides a video compensation method, which is suitable for an image distributor to provide a video signal of a host to at least one display device, and the image distributor transmits the video signal to the display device through a transmission line, and the video compensation is performed. The method comprises the steps of: connecting one of the first connectors of the transmission line to the image distributor, and the second connector of the other end is floating; turning on any two positions of the second connector to form a loop; Transmitting a test signal to the loop; receiving the returned test signal; calculating a round trip time of the test signal; providing a control signal according to the round trip time; connecting the second connector to the display device; and adjusting the video signal according to the control signal, and The adjusted video signal is transmitted to the display device. The advantages and spirit of the present invention, as well as the more detailed embodiments, may be further understood by the following embodiments and the accompanying drawings. 200930090 [Embodiment] As described in the prior art, the longer the transmission line length between the image distributor 12 and the display device 13 is, the more the attenuation of the video signal received by the display device 13 is. It can be seen that the degree of attenuation of the video signal is positively related to the length of the transmission line. Therefore, the technical content of the present invention includes measuring the length of the transmission line first, and then pre-compensating for the video signal output by the image distributor according to the measured length of the transmission line. That is to say, the image distributor of the present invention not only provides the video signal of the host to the at least one display device, but also has the video compensation function to compensate for the attenuation of the video signal caused by the length of the transmission line. Its towel, the domain of the brain can provide the host of video signals, such as: computer host, DVD player.. Please refer to FIG. 3 and _, which are schematic diagrams of two embodiments of the compensation function of the split-unit hair-distributing agent. As shown, image distributor 22 includes at least one output 224, a signal generator mi, and a compensation device 23. The output end 224 is used to connect a transmission line 24 having a first connector 241 and a second connector 242 at both ends of the transmission line, and the first connector 241 is connected to the output second connection of the image distributor 22. _ lose "峨13. The limbs are assigned H 2 _ display device 13 video transmission channels. In the preferred embodiment, the first connector 241 and the second connector 242 at both ends of the transmission line 24 are DB15 connectors. The signal generator 221 described above can transmit a test signal to the transmission line 24. The compensating device 23 can calculate the length of the transmission line 24 according to the round-trip time of the carrier-first transmission path or a second transmission path, and enter the 200930090 signal signal; or the compensation transmission path of the compensation device 23 Or the second transmission path, wherein the first transmission path refers to a path in which the test signal is reflected back through the unconnected pin 2421 of the second connector ,, and the second transmission path refers to the second connection. When either of the two positions of the 242 and 2423 are turned on to form a loop, the test signal is returned via the one of the above-mentioned pins. In the preferred embodiment, the conduction system of the box t 2422, 2423 can be carried out using the conductor element of the hopping. The compensation device 23 further includes a control unit (10) (10) C (mi1io1, MCU) 231 and a compensation circuit 232. The control unit 231 can be configured to receive the test signal returned by the first path or the second path, determine the return time of the test signal and provide a control signal according to the round trip time to control the compensation circuit 232 to compensate the video signal. In the preferred embodiment, the control signal can be derived from a round trip time of the test signal to a form 233 or a compensation parameter obtained from a lookup table. This control signal causes the compensation circuit 232 to generate a compensation signal. The compensation circuit 232 adjusts the video signal sent to the display device 13 according to the control signal. In this embodiment, the compensation circuit 232 adjusts a capacitance value according to the control signal to provide a compensation signal to the video signal. The video signal includes at least three signals R, G, and B. Before the three signals are transmitted to the display device 13, they are first passed through the compensation circuit 232, and then added (superimposed) the compensation signal, and then transmitted to the display device 13. Please refer to FIG. 5 , which is a schematic diagram of a video signal with a compensation signal output by the image distributor 22 of the present invention. As stated above, when the video signal plus 200930090 ^Compensation Wei Shi' will present a signal similar to Figure 5. Then, after the transmission of the tiU 转 转 转 转 转 转 转 转 转 转 24 24 24 24 24 24 24 ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’
• 與，機1G所輸^之原始.視訊訊號鶴大致相同，如圖二A 所不。如此-來’顯示裝置13所顯示的影像便不會有失真 的問題。 值得注意的是，上述所列舉的視職號型態，僅為方 便轉之用。本發明之技術特徵並非限定於上述之視訊訊 © 號型態。 為了更加清楚地顯示本發明所提出之補償方法，可將 圖二及圖四之示意圖分別配合相關的流程圖（圖六及圖七） 來描述。 請同時參賴三及圖六，其係為本發明補償方法之第 一實施例，亦即透過上述第一路徑所進行的補償方法。在 本實施例中，傳輸線24兩端之第一連接器241與第二連接 器242已分別連接至影像分配器22與顯示裝置η。第二 ® 連接器242具有一空腳位(⑽似以pin)2421，此空腳位2421 並未與顯示裝置13產生電性連接。也就是說，當一訊號透 過傳輸線24傳送到此空腳位2421時，此訊號會反射，然 後沿著原本線路回傳。 根據上述特性’本實施例的補償方法係包含下列步 驟：影像分配器22的信號產生器221發送一測試信號至第 一連接器241之一腳位2411(此腳位2411係對應至第二連 接器242之空腳位2421)。此測試信號經由傳輸線％傳送 至第二連接器242之空腳位2421 (S11)。測試信號到達第二 12 200930090 連接器242之空腳位2421後，隨即反射並沿原線路回傳至 上述第一連接器241之腳位2411。補償裝置23之控制單 •元231接收返回之測試信號(S12) ’並計算測試信號的往返 • 時間(S13)。 接著’補償裝置23之控制單元231係根據上述往返時 間，提供一控制訊號(S14)給補償電路232 ,在較佳實施例 中控制訊號可使補償電路232產生一補償訊號。最後，補 償電路232依據此補償訊號調整視訊訊號，並透過傳輸線 0 24傳送到顯示裝置13(S15)。 上述提供補償訊號之步驟，控制單元231係根據測試 信號的往返時間對照至表單233，或是依據一查表電路 (lookup table)，以產生控制訊號。其中，表單可包括一儲 存於記憶體内的對應資料；查表電路可包括一硬體電路。 。然後，補償電路232再依據該控制訊號，調整該視訊 訊號。其中，上述表單233儲存於影像分配器22内，其具 有測試信號的往返時間或各種線長所對應的補償參數資 泛料。控制單元231可根據往返時間及補償參數資料，取得 控制訊號。 或者，上述調整視訊訊號之步驟可根據測試信號的往 返時間，先計算傳輸線24長度。接著，根據傳輸線24長 度對照至表單233，以取得控制訊號^最後，藉由補償電 路，調整該視訊訊號，例如將該補償訊號疊加至該視訊訊 號。其中，上述表單233儲存於影像分配器22内，其具有 傳輸線24長度所對應的補償參數資料。控制單元231可根 據往返時間及補償參數資料’取得控制訊號。 13 200930090 四及圖七’其係為本發明補償方法之第 二二透過上述第二路徑所進行的補償方法。本 2^==^訂卿：魏，_傳輸線 24之長度’將傳輸線24之第一連接器2 Ο ❹ 配器則巧先暫時不將第二連接_連接至顯示】置 13 ’也就疋浮置第二連接器撕（S21)。利用一跳線27之 類的導體元件接通第二連接器Μ2之任兩腳位期、 2423 ’以形成-迴路(S22)。影像分配器22内之信號產生 器221發送一測試信號至第一連接器241之-腳位2412(此 腳位2412係對應至第二連接器242之腳位2422)。 β測試信號經由傳輸線24傳送至上述迴路(S23)，也就 是測試信號依序經過第一連接器241之腳位2412、傳輸線 24、第二連接器242之腳位2422、跳線27、第二連接器 242之另一腳位2423、傳輸線24後，再傳到第一連接器之 另一腳位2413(此腳位2413係對應至第二連接器242之腳 位2423)。接著，補償裝置23之控制單元231接收返回之 測试信號(S24)，並計算測試信號的往返時間(S25)。 接著，補償裝置23之控制單元231係根據上述往返時 間’提供一控制訊號(S26)給補償電路232。將傳輸線24 之第二連接器242連接至顯示裝置13(S27)。最後，補償電 路232依據控制訊號調整視訊訊號，並將調整後之視訊訊 號透過傳輪線24傳送到顯示裝置13(S28)。 而上述調整視訊訊號之詳細步驟，係與第一實施例之 補償方法相同，在此並不多加贅述。 另外’本發明之影像分配器可藉由多條傳輸線連接至 200930090 裝Γ由於每台顯示裝置與影像分配器間的距離 成不Η，所咖須透财同長度的傳輸線來連接。而本 供::補償ΐ法與補償裝置可根據不同的傳輸線長度，提 =當的補償訊號。藉此，每台顯示妓皆能顯示出原ί 應有的影像品質。 .j 綜上所述’本發明之影像分配器與補償方法係： -、對於傳輸線長度所會造成的視訊職祕做一預 ^償’使顯示裝置的影像不會有失真或拖影的 以 提供好的影像品質。 二、 可根據不同的傳輸線長度，提供適當的補償訊號， 使每台顯示裝置皆能顯示出原本應有的影像品質。 三、 傳輸線長度的量測裝置係設置於影像分配器内， 任何可用來傳輸視訊的傳輸線，只要連接至影像分配器即 可進行線長的量測。. ❹ 本發明雖以較佳實例闡明如上，然其並非用以限定本 發明精神與發明實體僅止於上述實施姻。對熟悉此項技 術者富了輕易了解並利用其它元件或方式來產生相同的 功效。是以，在不脫離本發明之精神與範圍内所作之修改， 均應包含在下述之申請專利範圍内。 【圖式簡單說明】 藉由以下詳細之描述結合所附圖示，將可輕易的了解 上述内容及此項發明之諸多優點，其中： 圖一係為習知影像分配系統示意圖； 15 200930090 係為影像分配系統之主機所輸出之視訊訊號 圖二A 示意圖； 圖一 B係為習知影像分配系統之顯示農置所接收到 之視訊訊號之示意圖；_ 圖三係為本發明影像分配器執行補償功能之示意 ngt · 園， 圖四係為本發明影像分配器執行補償功能之另一之 實施例； 圖五係為本發明影像分配器所輸出之具有補償訊號 之視訊訊號示意圖； 圖六係為本發明之補償方法流程圖；以及 圖七係為本發明另一實施例之補償方法流程圖。 【主要元件符號說明】• It is roughly the same as the original video signal crane that was sent by the 1G machine, as shown in Figure 2A. Thus, the image displayed by the display device 13 does not have a problem of distortion. It is worth noting that the above-mentioned list of job title types is only for convenience. The technical features of the present invention are not limited to the above-described video signal type. In order to more clearly show the compensation method proposed by the present invention, the schematic diagrams of FIG. 2 and FIG. 4 can be respectively described in conjunction with the related flowcharts (FIG. 6 and FIG. 7). Please refer to FIG. 3 and FIG. 6 simultaneously, which is the first embodiment of the compensation method of the present invention, that is, the compensation method performed through the first path. In the present embodiment, the first connector 241 and the second connector 242 at both ends of the transmission line 24 have been connected to the image distributor 22 and the display device n, respectively. The second ® connector 242 has an empty pin ((10) like pin) 2421 that is not electrically connected to the display device 13. That is to say, when a signal is transmitted to the empty pin 2421 through the transmission line 24, the signal is reflected and then transmitted back along the original line. According to the above characteristics, the compensation method of the present embodiment includes the following steps: the signal generator 221 of the image distributor 22 sends a test signal to one of the pins 2411 of the first connector 241 (this pin 2411 corresponds to the second connection). The empty position of the 242 is 2421). This test signal is transmitted to the empty pin 2421 of the second connector 242 via the transmission line % (S11). After the test signal reaches the empty pin 2421 of the second 12 200930090 connector 242, it is reflected and transmitted back along the original line to the pin 2411 of the first connector 241. The control unit 231 of the compensating means 23 receives the returned test signal (S12)' and calculates the round trip time of the test signal (S13). Next, the control unit 231 of the compensating device 23 provides a control signal (S14) to the compensation circuit 232 according to the round trip time. In the preferred embodiment, the control signal causes the compensation circuit 232 to generate a compensation signal. Finally, the compensation circuit 232 adjusts the video signal based on the compensation signal and transmits it to the display device 13 via the transmission line 0 24 (S15). In the above step of providing the compensation signal, the control unit 231 compares the round-trip time of the test signal to the form 233 or according to a lookup table to generate a control signal. The form may include a corresponding data stored in the memory; the look-up table circuit may include a hardware circuit. . Then, the compensation circuit 232 adjusts the video signal according to the control signal. The form 233 is stored in the image distributor 22, and has a round trip time of the test signal or a compensation parameter corresponding to various line lengths. The control unit 231 can obtain the control signal according to the round trip time and the compensation parameter data. Alternatively, the step of adjusting the video signal may first calculate the length of the transmission line 24 according to the return time of the test signal. Then, the length of the transmission line 24 is compared to the form 233 to obtain the control signal. Finally, the video signal is adjusted by the compensation circuit, for example, the compensation signal is superimposed on the video signal. The form 233 is stored in the image distributor 22 and has compensation parameter data corresponding to the length of the transmission line 24. The control unit 231 can obtain the control signal based on the round trip time and the compensation parameter data. 13 200930090 IV and Fig. 7' are the compensation methods performed by the second path through the second path of the second compensation method of the present invention. Ben 2^==^Booking: Wei, _ length of transmission line 24 'The first connector 2 of the transmission line 24 Ο ❹ The adapter will not connect the second connection _ to the display temporarily] Set 13 'is also floating The second connector is torn (S21). A conductor element such as a jumper 27 is used to turn on any two-bit period, 2423' of the second connector Μ2 to form a loop (S22). The signal generator 221 in the image distributor 22 sends a test signal to the pin 2412 of the first connector 241 (this pin 2412 corresponds to the pin 2422 of the second connector 242). The beta test signal is transmitted to the above loop via the transmission line 24 (S23), that is, the test signal sequentially passes through the pin 2412 of the first connector 241, the transmission line 24, the pin 2422 of the second connector 242, the jumper 27, and the second. The other pin 2423 of the connector 242, after the transmission line 24, is transmitted to the other pin 2413 of the first connector (this pin 2413 corresponds to the pin 2423 of the second connector 242). Next, the control unit 231 of the compensating means 23 receives the returned test signal (S24), and calculates the round trip time of the test signal (S25). Next, the control unit 231 of the compensating device 23 supplies a control signal (S26) to the compensation circuit 232 based on the round-trip time described above. The second connector 242 of the transmission line 24 is connected to the display device 13 (S27). Finally, the compensation circuit 232 adjusts the video signal according to the control signal, and transmits the adjusted video signal to the display device 13 through the transmission line 24 (S28). The detailed steps of adjusting the video signal are the same as those of the first embodiment, and are not described here. In addition, the image distributor of the present invention can be connected to the 200930090 by a plurality of transmission lines. Since the distance between each display device and the image distributor is not enough, the coffee beans must be connected to the same length of the transmission line. And this:: The compensation method and the compensation device can provide the compensation signal according to the length of the different transmission lines. In this way, each display can display the original image quality. .j In summary, the image distributor and compensation method of the present invention is: - a pre-compensation for the video secrets caused by the length of the transmission line, so that the image of the display device is not distorted or smeared. Provide good image quality. Second, according to the length of different transmission lines, provide appropriate compensation signals, so that each display device can display the original image quality. 3. The measuring device for the length of the transmission line is set in the image distributor. Any transmission line that can be used for transmitting video can be measured by the line length as long as it is connected to the image distributor. The present invention has been described above by way of a preferred example, and it is not intended to limit the spirit of the invention and the invention of the invention. It is easy for those skilled in the art to understand and utilize other components or methods to produce the same effect. Modifications made within the spirit and scope of the invention are intended to be included within the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The above and other advantages of the invention will be readily understood by the following detailed description in conjunction with the accompanying drawings in which: FIG. 1 is a schematic diagram of a conventional image distribution system; 15 200930090 is Figure 2B is a schematic diagram of the video signal outputted by the host of the image distribution system; Figure 1B is a schematic diagram showing the video signal received by the farmer in the conventional image distribution system; _ Figure 3 is the image dispenser of the present invention performing compensation The function of the function is ngt · garden, FIG. 4 is another embodiment of the image dispenser performing compensation function of the present invention; FIG. 5 is a schematic diagram of the video signal with the compensation signal output by the image distributor of the present invention; A flowchart of a compensation method of the present invention; and FIG. 7 is a flowchart of a compensation method according to another embodiment of the present invention. [Main component symbol description]
10 :主機 122 ·輸入端 13 :顯示裝置 221 :信號產生器 231 :控制單元 233 :表單 242 :第二連接器 12、22 :影像分配器 124、224 :輸出端 14、24 :傳輸線 23 :補償裝置 232 :補償電路 241 :第一連接器 2421 :空腳位 2411、2412、2413、2422、2423 :腳位 27 :跳線10: host 122 · input 13 : display device 221 : signal generator 231 : control unit 233 : form 242 : second connector 12 , 22 : image distributor 124 , 224 : output 14 , 24 : transmission line 23 : compensation Device 232: compensation circuit 241: first connector 2421: empty positions 2411, 2412, 2413, 2422, 2423: pin 27: jumper