Device for video decompression and display

• US 20070280357A1
• Filed: 05/31/2006
• Published: 12/06/2007
• Est. Priority Date: 05/31/2006
• Status: Abandoned Application

• Current Assignee: Taiwan Imaging Tek Corporation
• Original Assignee: Taiwan Imaging Tek Corporation
• Inventors: Sung, Chih-Ta Star
• Application Number:
  US11/443,522
• Publication Number:
  US 20070280357A1
• Time in Patent Office: Days
• US Class Current: 375/240.250
• CPC Class Codes: H04N 19/42 characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/423 characterised by memory arrangements H04N19/433 takes precedence
• CPC Class Codes: H04N 19/426 using memory downsizing methods
• CPC Class Codes: H04N 19/428 Recompression, e.g. by spatial or temporal decimation
• CPC Class Codes: H04N 19/44 Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 21/4122 additional display device, e.g. video projector digital output for controlling a plurality of local displays G06F3/1423
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/44008 involving operations for analysing video streams, e.g. detecting features or characteristics in the video stream arrangements characterised by components specially adapted for monitoring, identification or recognition of video in broadcast systems H04H60/59
• CPC Class Codes: H04N 21/440254 by altering signal-to-noise parameters, e.g. requantization
• CPC Class Codes: H04N 21/440263 by altering the spatial resolution, e.g. for displaying on a connected PDA

Abstract

A device of decompressing video data, scaling the image and displaying to a displaying device significantly reduces the power consumption. The compressed video data is reconstructed and temporarily compressed before storing into a temporary display frame buffer and decompressed before displaying in a display device. A video data is partially decoded to the DCT domain and scaled according to the resolution of display before the video decompression. A video communication device includes an image sensor integrated together with the video compression engine into the same die and a display driver with the video decompression engine integrated together in the same die.

Claims

1. A device of video data decompression and displaying, comprising:

a decompression engine to reconstruct the compressed video data with a first storage device for temporarily saving the referencing frame image;

a second storage device functioning as a display frame buffer to temporarily save the reconstructed pixels to be driven out to be displayed;

an image compression codec to compress the image before saving into the second storage device of the display frame buffer and to decompress the pixels accessed from the display frame buffer before driving out to the display driver and display panel;

a timing control unit which determines the time to drive out the corresponding pixels to the display panel; and

a display driver comprising;

a source driver to drive out at least the Red, Green and Blue color components each pixel;

a gate driver to select the row of pixels to be driven out to the display panel.

2. The method of claim 1, wherein the compressed video source input to the video decompression engine is comprised of at least one of Y, Cr, Cb or Y, U, V elements with the data ratio of 4:

2;

2 or 4;

2;

0 or 4;

4;

4 format.

3. The method of claim 1, wherein the image source of the display image buffer is comprised of pixel data with YUV format and is converted to be Red, Green, Blue color elements before driving out to the display media.

4. The method of claim 1, wherein the source driver of the display driver drives out the pixels line by line with a line shifter coupled between the image decompression unit which reconstructs the pixels of the display image buffer and a line buffer.

5. A device of video data decompression, comprising:

a decompression engine to reconstruct the compressed video data including;

a variable length decoder to block by block decode and reconstruct the DCT coefficients;

de-quantization unit to multiply the DCT coefficients by the corresponding values of the quantization matrix to shift the DCT coefficients to the right values;

inverse DCT to transform the DCT coefficients to the time domain pixels in I-type coding or pixel differences in inter-frame coding; and

motion compensation unit to add the difference of block pixels to the block of pixels of the referencing frame in inter-frame coding;

a storage device for temporarily saving the referencing frame pixels; and

an image compression and decompression engine coupled between the video decompression engine and the referencing frame buffer to compress the image to be saved to the referencing frame buffer and to access the compressed image from the frame buffer and reconstruct them to be reference in the video decompression engine.

6. The device of claim 5, wherein a compression engine used to reduce the data rate of the referencing frame compresses the image block by block with each block pixels having the same output bit rate.

7. The device of claim 6, wherein a block is comprised of smaller amount of pixels compared to the block size for the motion compensation.

8. The device of claim 5, wherein the referencing frame buffer and the compression codec reside on the same die with the video decompression engine.

9. The device of claim 5, wherein the compressed video data is comprised of MPEG video compression data stream.

10. The device of claim 9, wherein the video compression engine compressed video data of Y, U, V or Y, Cr, Cb color components.

11. An apparatus of scaling, decompressing and displaying the video frame, comprising

a first decompression engine includes the video header decoder, a variable length decoder, and a dequantizer to recover the compressed frequency domain video data of DCT coefficients to block based information;

a scaler scales the video frame size according to the resolution of the display screen by re-calculating the DCT coefficients reconstructed by the first decompression engine;

a second decompression engine to block by block reconstruct the scaled video data includes the inverse DCT, and a motion compensation unit to add/subtract the block difference between the targeted block and the corresponding block of the referencing frame; and

a display driver which includes a timing controller unit to decide the time to driver out the corresponding pixels to the display panel, source and gate driver, an RAM temporarily storing the pixels to be driven out to the display panel and a still image codec engine to compress and decompress the image to be stored into the temporary image buffer.

12. The device of claim 11, wherein in the first decompression engine, the variable length decoding and de-quantization are applied to recover the DCT coefficients of block pixels.

13. The device of claim 11, wherein the timing control unit calculates the timing of driving out the corresponding pixels color elements of each row by sending signal to the gate drive, the source driver and the frame buffer of image regarding the right timing and location of frame pixels to be displayed.

14. A video communication device, comprising

A first device integrating image sensor and a video compression engine integrated on the same die;

A transceiver which transmits the compressed video data out which is generated from the first device and receives the compressed data and sends to the display device; and

A display device including a display panel and a display driver with the display image buffer and its corresponding compression codec and a video decompression unit integrated in the same die.

15. The device of claim 14, wherein the image sensor device is made of a semiconductor image sensing element.

16. The device of claim 14, wherein the semiconductor sensing element is a CMOS image sensor.

17. The device of claim 14, wherein the video compression engine includes a memory array storing at least one referencing frame buffer into the same die.

18. The device of claim 14, wherein the display driver includes a source driver driving out the pixels to the display panel, a gate driver selecting the row of pixels to be driven out and a timing controller deciding the time to drive the corresponding row of pixels.

19. The device of claim 14, wherein the video decompression engine includes a decompression engine, another compression codec to reduce the data rate of the referencing frame buffer and a memory array to temporarily save the compressed frame pixels.

20. The device of claim 14, wherein the reconstructed frame to be displayed is compressed by an engine before storing to the display image buffer and is decompressed before sending to the display driver.