Abstract:
A video playback system and the video playing method thereof. The video playback system includes a display panel, a video player for outputting a CCIR video, and a control circuit including a CCIR transformer and a timing controller. The CCIR transformer receives the CCIR video and transforms it to image data. The timing controller receives the image data and outputs a control timing and pixel data for controlling the panel.

Description:
[0001]     This application claims the benefit of Taiwan application Serial No. 93122626, filed Jul. 28, 2004, the subject matter of which is incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The invention relates in general to a video playback system and the video playing method thereof, and more particularly to a video playback system capable of reducing power consumption, and the video playing method thereof.  
         [0004]     2. Description of the Related Art  
         [0005]     Due to technological advancements, electronics companies nowadays are not only directing their product development towards light-weight, thin, short, and small components, but are also emphasizing on developing products that are more power conserving. Especially with regards to portable personal entertainment systems, such as portable DVD players, consumers rely primarily on the internal batteries to run the players, and because of such circumstances, it is particularly important that power consumption is considered in the design of the products.  
         [0006]      FIG. 1A  is a conventional video playback system  100 . The video playback system  100  includes a video player  110 , a control circuit  130 , and a display panel  180 . For illustration, display panel  180  is assumed to be an analog display panel. The video player  110  includes a MPEG decoder  112 , a video processor  114 , and an image encoder  116 . MPEG decoder  112  is for receiving encoded data read from compact discs, and outputting decoded data. The MPEG decoder  112  provides decoding methods such as in MPEG1, MPEG2, and MPEG4 etc. The video processor  114  receives decoded data and outputs video data D 0  in digital format. Image encoder  116  receives digital video data, and converts digital video data to analog video data A 1 , such as composite video or S-video data. Also, the image encoder  116  outputs a control timing C 1 .  
         [0007]     The control circuit  130  includes a sync separator  131 , a timing controller  132 , and an image decoder  134 . The sync separator  131  is for receiving the control timing C 1  output from the video player  110 , then separating the control timing into different sync timings, and finally outputting the control timing C 1 . The image decoder  134  is for receiving image data A 1 , then digitizing and decoding image data A 1 , and finally outputting image data D. The timing controller  132  then converts image data D into analog pixel data P, and outputs analog pixel data P according to timing signal C 2 .  
         [0008]      FIG. 1B  shows a block diagram of image decoder  134 . The image decoder  134  includes an analog input interface  141 , an A/D Converter (ADC)  142 , an image processor  143 , and a scaler  144 . Image data A 1  is first received by the analog input interface  141 , and is then fed into the ADC  142  to be converted into digital data, and is in turn processed by the image processor  143  and the scaler  144  to output image data D. The image processor  143  can perform various controls such as brightness, hue, and gamut adjustments, while the scaler  144  can perform image size scaling.  
         [0009]     Since conventional displays, such as CRT televisions having control circuit  130  and display panel  180  as described above, are only built to receive analog signals. Thus, the video player  110  has to encode the internally processed digital signals into analog image data A 1  before transferring. Consequently, conventional video playback systems must perform multiple analog-to-digital (A/D) and digital-to-analog (D/A) conversions, and resulting in signal data loss, overuse of power consumption, and unnecessary waste of costs and resources etc.  
         [0010]     To better illustrate, the image encoder  116  for example first performs a D/A conversion, then the image decoder  134  performs a A/D conversion, then the timing controller  132  again performs another D/A conversion. While performing A/D or D/A signal conversions, a greater amount of power is consumed, and since conventional video playback systems require signals to go through multiple levels of A/D and D/A conversions, power consumption can not be effectively reduced.  
       SUMMARY OF THE INVENTION  
       [0011]     It is therefore an object of the invention to provide a video playback system capable of reducing power consumption, and the video playing method thereof.  
         [0012]     The International Radio Consultative Committee (CCIR) interfaces are commonly used as the interface between video decoders and display control ICs (Scaler, Timing Controller), for applying internally to the display system. The CCIR interface under present invention is being implemented, in novelty, between the video playback system and the display system. By such implementation, the D/A conversions are no longer required in video playback systems, and in digital display systems, the A/D conversions are no longer required as well. Thus, the system costs can be effectively reduced, while arriving at better picture quality. Similarly, for analog playback systems, by eliminating the D/A conversion originally required in video players, better picture quality can also be achieved.  
         [0013]     The invention achieves the above-identified object by providing a video playback system, including a video player, a control circuit, and a display panel. The video player is for outputting a CCIR video. The control circuit includes a CCIR transformer and a timing controller. The CCIR transformer if for receiving and converting the CCIR video into image data. The timing controller is for receiving image data, and outputting a control timing and image data. The display panel is for receiving image data and control timing, and outputting picture frames accordingly.  
         [0014]     The invention achieves another above-identified object by providing a method of displaying video. First, the CCIR transformer is utilized to receive the CCIR video and transform the CCIR video to image data. Next, utilizing the timing controller, image data is received, and then pixel data and a control timing are outputted. Then, according to pixel data and the control timing, picture frames are displayed on the display panel.  
         [0015]     Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIGS. 1A and 1B  show illustrations of a conventional video playback system.  
         [0017]      FIG. 2  is block diagram of a video playback system  200  according to an embodiment of the invention.  
         [0018]      FIG. 3  shows block diagram illustrating the CCIR transformer  234 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]      FIG. 2  is block diagram of a video playback system  200  according to an embodiment of the invention. Video playback system  200  is, for example, a portable DVD player, and includes a video player  200  and a display module. The display module includes control circuit  230  and a display panel  280 . Video player  220  is for outputting a CCIR video D 1 . Control circuit  230  is for receiving the CCIR video D 1  and outputting pixel data P and control timing C 2  accordingly. Display panel  280  then displays picture frames according to control timing C 2  and pixel data P. The CCIR video is the video format standard set out by the International Radio Consultative Committee (CCIR).  
         [0020]     Video player  220  includes a MPEG decoder  212 , a video processor  214 , and an image encoder  216 . MPEG decoder  212  is for receiving and decoding encoded data into decoded data for output. The decoded data are for instance data read from a DVD. Video processor  214  receives the decoded data and outputs the video data accordingly, then image encoder  216  in turn receives the video data and outputs a CCIR video D 1  in digital format. The CCIR video D 1  is for example a CCIR 601/656 4:2:2 of YCbCr format.  
         [0021]     Control circuit  230  includes a CCIR transformer  234  and a timing controller  232 . CCIR transformer  234  receives the CCIR video D 1 , then transforms CCIR video D 1  into image data D 2 , and extracts control timing C 1  from image data D 2 . Timing controller  232  then receives image data D 2  and control timing C 1 , and outputs pixel data P and control timing C 2  accordingly.  
         [0022]      FIG. 3  shows a block diagram illustrating the CCIR transformer  234 . CCIR transformer  234  includes a CCIR interface  310 , a sync signal generator  340 , a converting unit  320 , and a scaler  330 . CCIR interface  310  is for receiving CCIR video D 1 . Converting unit  320  receives CCIR video D 1  via CCIR interface  310  and outputs a RGB video. The scaler  330  receives and scales the RGB video, and outputs image data D 2 . Sync signal generator  340  receives CCIR video D 1  via CCIR interface  310 , and extracts a sync timing contained in CCIR video D 1  to generate a control timing C 1 .  
         [0023]     The difference between the embodiment of present invention ( FIG. 2 ) and the conventional embodiment ( FIG. 1 ) is primarily that the present invention utilizes the CCIR interface to replace the conventional composite video signal (CVBS) or S-Video interfaces. Since the die size of CCIR transformer is much smaller compared to that of CVBS or S-Video video decoders, the costs can be effectively reduced.  
         [0024]     In addition, for the CCIR transformer according to the embodiment of present invention, the input video signals are not required to undergo data conversions through ADCs, thus data loss resulting from analog to digital conversions can be prevented, and data can be presented as picture frames in the most realistic form.  
         [0025]     Furthermore, the brightness, hue and gamut adjustments originally handled by conventional image processors can now be performed by video player  220 . Therefore, functions required for CCIR transformer  234  can be greatly reduced, which directly translates to the reduction of die size and manufacturing costs  
         [0026]     The display panel  280  according to the embodiment of the invention can be in analog format or in digital format. When display panel  280  displays in analog format, pixel data P output by timing controller  232  is also in analog format, such as in interlaced RGB format; when display panel  280  displays in digital format, pixel data is also in digital format, such as in LVDS, DV1 etc.  
         [0027]     The video play back system as according to above mentioned embodiment of the present invention can be concluded to have the following advantages: 
        1. Costs reduction     Without having to use the image decoder for decoding, costs of manufacturing image decoder can be reduced, thus effectively reducing overall system costs.     2. Good picture quality     With this novel system architecture, video signals undergo neither digital to analog conversions, nor analog to digital conversions. Hence, the data can be prevented from being lost during conversions, and thus the data is presented as picture frames in the most realistic form.     3. Conserve power consumption     The videos output by the video player are digital format CCIR videos; therefore, during output, the video player does not need to perform D/A conversions, and the CCIR converter in the control circuit does not need to perform A/D conversions either. Since the invention eliminates the unnecessary A/D and D/A format conversions, power consumption can be effectively reduced.     4. Control circuit can be integrated on the display panel, allowing the size of the video playback system to reduce even further.        
 
         [0035]     While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. Rather, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.