CN200944646Y - Video conference terminal for improving image quality - Google Patents

Abstract

A video conferencing terminal for improving image quality, including an analog video decoder for converting interlaced analog video signals into digital video signals, a video compression module for performing video compression on the digital video signals, and sending video compressed code streams A communication module that receives the compressed video code stream from the communication line, a video decompression module that decompresses the compressed video code stream, and a video decompression module that converts the decompressed digital video signal into an analog video signal output An analog video encoder; and several modules for processing audio signals; the interlaced digital video code stream decompressed by the video decompression module is converted into a progressive digital video code stream and output between the video decompression module and the analog video encoder Interlaced to progressive module. It overcomes the problems of low image refresh rate and flickering image caused by inputting and outputting interlaced video signals of existing equipment, improves image quality, and does not occupy too high bandwidth.

Description

A video conferencing terminal with improved image quality

technical field

The utility model relates to the field of video input and video output devices, in particular to a video conference terminal for improving image quality.

Background technique

At present, the general video input and video output of ordinary video conferencing terminals on the market are interlaced analog video signals, and the common ones are PAL (Phase Alternating Line, progressive phase inversion) system and NTSC (National Television System Committee, National Television System Committee) Standard composite video signal, as shown in Figure 1, it includes an analog video decoder A that converts the interlaced analog video signal into a digital video signal, and a video compression module B that performs video compression on the above-mentioned digital video signal. The above-mentioned video compression code stream is sent to the communication line and the communication module E that receives the compressed video code stream from the communication line, a video decompression module C that performs video decompression on the compressed video code stream transmitted by the communication module E, and a The decompressed digital video signal is then converted into an analog video signal and output by an analog video encoder D. It also includes an audio input module F, an audio compression module G, an audio decompression module H and an audio output module I for processing audio signals.

We know that compared with progressive video signals, the disadvantage of interlaced video signals is that the image refresh rate is low, resulting in flickering images, and it is easy to make people feel eye fatigue when watching for a long time; but the advantage is that it reduces the image compression and decompression of video conferencing terminals. Compressing the amount of calculation also reduces the bandwidth required to transmit the code stream, which saves a lot of cost. Although the video conferencing terminal fully adopting high-definition video technology no longer has the disadvantages of interlaced video signals, its image compression and decompression calculations are very large. Under the current technical conditions, its implementation difficulty and manufacturing cost have greatly increased. , and because the compressed data rate is higher, the meeting needs to occupy a higher bandwidth, which increases the cost of using the video conference.

Utility model content

The purpose of this utility model is to provide a video conferencing terminal with improved image quality, which solves the technical problem that the image refresh rate of the existing video conferencing terminal input and output interlaced video signals is low, resulting in a flickering image, which not only improves the image quality, but also improves the image quality. Does not take up too much bandwidth.

For solving the problems of the technologies described above, the technical solution of the utility model is:

A video conferencing terminal for improving image quality, which includes an analog video decoder for converting interlaced analog video signals into digital video signals, a video compression module for performing video compression on the digital video signals, and a video compression code for the above-mentioned A communication module that sends the stream to the communication line and receives the compressed video stream from the communication line, a video decompression module that performs video decompression on the compressed video stream transmitted by the communication module, and a video decompression module that decompresses the above-mentioned decompressed digital video signal An analog video encoder that is converted into an analog video signal for output, and an audio input module, an audio compression module, an audio decompression module, and an audio output module that process audio signals. It is characterized in that: the video decompression module and the analog video encoder are provided with a video interlaced converter that converts the interlaced digital video code stream decompressed by the video decompression module into a progressive digital video code stream and outputs it to the analog video encoder. Progressive module.

The video decompression module is a media processor.

In the case that the video decompression computing capability of the above-mentioned media processor is sufficient, the function of the video interlaced-to-progressive module is also realized by the media processor.

By virtue of the above technical solutions, the utility model has the following technical effects.

The utility model can convert the interlaced video signal input by the video conferencing terminal into a progressive video signal before outputting, so that the video output of the video conferencing terminal can obtain a better quality on the standard-definition television and high-definition television The image solves the shortcoming of flickering of the interlaced video signal output by the original video conferencing terminal, improves the image quality, and the implementation cost of this method increases less, and the implementation difficulty is also relatively low.

Description of drawings

Fig. 1 is a structural schematic block diagram of an existing video conferencing terminal;

Fig. 2 is a structural schematic block diagram of a video conferencing terminal of the present invention;

Fig. 3 is a schematic diagram of a specific embodiment of the utility model.

Detailed ways

Please refer to FIG. 2 , which is a structural schematic diagram of a video conferencing terminal for improving image quality of the present invention. As shown in the figure: it includes an analog video decoder 1 that converts interlaced analog video signals into digital video signals, a video compression module 2 that performs video compression on the above-mentioned digital video signals, and sends the above-mentioned video compression code stream to A communication line and a communication module 5 receiving compressed video code stream from the communication line, a video decompression module 3 for decompressing the above-mentioned compressed video code stream transmitted through the communication module 5, and a digital video after the above-mentioned decompression The signal is converted into an analog video encoder 4 for analog video signal output; it also includes an audio input module 7, an audio compression module 8, an audio decompression module 9 and an audio output module 10 for processing audio signals. The difference with the existing device is: between the video decompression module 3 and the analog video encoder 4, an interlaced digital video code stream decompressed by the video decompression module 3 is converted into a progressive digital video code stream and sent to The video interlaced conversion module 6 output by the analog video encoder 4 is progressive.

The video decompression module 3 of the video conferencing terminal is a media processor. When in use, it can decompress the remote compressed video stream and output the digital video code stream, and the digital video code stream is sent to the video interlaced to progressive module 6 The interlaced video signal is converted into a progressive video signal for output, and the progressive digital video signal is sent to an analog video encoder 4 for video digital-to-analog conversion to output a progressive analog video signal. The progressive analog video signal can be displayed relatively well on TVs supporting progressive video signals, such as standard definition television and high definition television, which improves the image quality output by the video conferencing terminal.

When the computing power of the video decompression media processor is sufficient, the computing work of the interlaced to progressive module 6 can also be undertaken by the media processor; or a media processor or an interlaced to progressive chip can be used alone to undertake the interlaced Switch to the operation of the row-by-row module 6. The realization method of the interlaced to progressive conversion is mainly to double the scan lines of one field to become one frame by means of interpolation, and the interpolated scan lines are calculated by the data of adjacent lines. There are many kinds of interpolation methods, such as direct copy method (copy the image data of the previous line directly as the image data of the inserted line), two-line average method (take the average value of the image data of the two lines before and after as the image data of the inserted line) image data) and so on.

Please refer to Fig. 3, which is a structural schematic diagram of a specific embodiment of the present utility model. As shown in the figure: the analog video decoder uses Philips' analog video decoder SAA7118 to complete the conversion of video analog signals to digital signals; Texas Instruments' TMS320DM642 is a media processor, so TMS320DM642-1 is mainly used for video compression Work, TMS320DM642-2 mainly does video decompression work, TMS320DM642-3 mainly completes the operation of video interlaced to progressive; ADV7310 is an analog video encoder, which completes the conversion of video digital signals to analog signals.

The working process is as follows: the analog video signal output from the camera is sent to the SAA7118 of the video conferencing terminal for video analog-to-digital conversion, converted into digital video signal and sent to TMS320DM642-1 for video compression, and the compressed code stream will be transmitted through the communication module to the video conferencing terminal at the remote venue; the compressed video stream transmitted from the remote venue is sent to TMS320DM642-2 for video decompression through the communication module, and the decompressed digital video signal is sent to TMS320DM642-3 for processing and interlaced conversion Progressive operation, convert the interlaced video signal into a progressive digital video signal output, the progressive digital video signal is sent to the analog video encoder ADV7310 for digital-to-analog conversion, and output an analog progressive video signal.

The foregoing is an embodiment of a video conferencing terminal that converts video from interlaced to progressive. In this example, the video decompression module and the video interlaced to progressive module are separated and completed by two media processors, TMS320DM642-2 and TMS320DM642-3 respectively. TMS320DM642-3 can be replaced by video interlaced to progressive chip, such as PW1235 of PIXELWORKS company. In the case that the amount of computation of TMS320DM642-2 is sufficient, the combination of video decompression and video interlaced to progressive conversion can also be completed by TMS320DM642-2, which saves TMS320DM642-3.

To sum up, the above are only preferred embodiments of the present utility model, and are not intended to limit the implementation scope of the present utility model. That is, all equivalent changes and modifications made according to the content of the patent scope of the utility model should be within the technical category of the utility model.

Claims (4)

1. A video conferencing terminal for improving image quality, which includes an analog video decoder (1) that converts interlaced analog video signals into digital video signals, and a video compression module (2) that performs video compression on the above-mentioned digital video signals ), a communication module (5) that sends the above-mentioned video compression code stream to the communication line and receives the compressed video code stream from the communication line, and carries out video decompression on the above-mentioned compressed video code stream transmitted through the communication module (5). Decompression module (3), one converts the above-mentioned decompressed digital video signal into an analog video encoder (4) for analog video signal output; and an audio input module (7) and an audio compression module (8) for processing audio signals ), audio decompression module (9) and audio output module (10); it is characterized in that: a video decompression module (3) is decompressed between the video decompression module (3) and the analog video encoder (4) The compressed interlaced digital video code stream is converted into a progressive digital video code stream and is output to the video interlaced to progressive module (6) of the analog video encoder (4). 2. The video conferencing terminal for improving image quality according to claim 1, wherein the video decompression module is a media processor. 3. The video conferencing terminal for improving image quality according to claim 1, characterized in that: the video interlaced-to-progressive module (6) is a media processor or an interlaced-to-progressive chip. 4. The video conferencing terminal for improving image quality according to claim 1, 2 or 3, characterized in that: the video interlaced-to-progressive module (6) doubles the scan lines of one field by interpolation into a frame.

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