Method and apparatus for encoding/decoding image data

• US 5,212,742 A
• Filed: 05/24/1991
• Issued: 05/18/1993
• Est. Priority Date: 05/24/1991
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Chu, Ke-Chiang, Normile, James O., Wright, Daniel W., Yeh, Chia L.
• Primary Examiner(s): Razavi, Michael T.
• Assistant Examiner(s): COUSO, YON JUNG
• Application Number:
  US07/705,284
• Time in Patent Office: 725 Days
• Field of Search: 362/27, 362/49, 362/56, 362/41, 340/752
• US Class Current: 382/166
• CPC Class Codes: H04N 19/107 between spatial and temporal predictive coding, e.g. picture refresh
• CPC Class Codes: H04N 19/30 using hierarchical techniques, e.g. scalability H04N19/63 takes precedence
• 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 19/436 using parallelised computational arrangements
• CPC Class Codes: H04N 19/503 involving temporal prediction adaptive coding with adaptive selection between spatial and temporal predictive coding H04N19/107; adaptive coding with adaptive selection among a plurality of temporal predictive coding modes H04N19/109
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/236 Assembling of a multiplex stream, e.g. transport stream, by combining a video stream with other content or additional data, e.g. inserting a URL [Uniform Resource Locator] into a video stream, multiplexing software data into a video stream; Remultiplexing of multiplex streams; Insertion of stuffing bits into the multiplex stream, e.g. to obtain a constant bit-rate; Assembling of a packetised elementary stream multiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 5/783 Adaptations for reproducing at a rate different from the recording rate
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 7/54 the signals being synchronous H04N21/23602, H04N21/23614, H04N21/2365, H04N21/2368, H04N21/4341, H04N21/4342, H04N21/4347, H04N21/4348 take precedence
• CPC Class Codes: H04N 9/8047 using transform coding

Abstract

An apparatus and method for processing video data for compression/decompression in real-time. The apparatus comprises a plurality of compute modules, in a preferred embodiment, for a total of four compute modules coupled in parallel. Each of the compute modules has a processor, dual port memory, scratch-pad memory, and an arbitration mechanism. A first bus couples the compute modules and a host processor. Lastly, the device comprises a shared memory which is coupled to the host processor and to the compute modules with a second bus. The method handles assigning portions of the image for each of the processors to operate upon.

Claims

1. A method in a video display system of partitioning an image for processing by N processing units coupled in parallel to an input means for receiving said image, said image of dimensions of H rows and W columns, comprising the following steps:

a. initializing an index variable i;

b. assigning an ith horizontal region of said image in the input means to an ith processing unit, said ith region starting at a ith starting position and ending at the ith starting position offset by a partition length value of H/N, said ith region comprising W columns, and H/N and an overlap number of complete rows, said overlap number of rows being shared with a next processor, and

c. incrementing said index variable i and repeating step b if said index variable i is less than N.

2. The method of claim 1 wherein the ith region of said image is assigned to a ith processing means, said processing means comprising a processor, a local memory and a means for receiving said ith region of said image.

3. The method of claim 1 wherein each of said regions comprises blocks of luminance and chrominance information.

4. The method of claim 1 wherein said processing comprises compressing said image.

5. The method of claim 1 wherein said image comprises one in a plurality of images.

6. The method of claim 5 wherein said processing comprises compressing said plurality of images.

7. The method of claim 5 wherein said processing comprises decompressing said plurality of images.

8. The method of claim 1 wherein said processing comprises decompressing said image.

9. A method in a video display system of partitioning an image for processing by N processing units coupled in parallel to an input means for receiving said image, comprising the following steps:

a. assigning an ith horizontal region of said image in the input means to an ith processing unit, said ith region starting at a ith starting position and ending at the ith starting position offset by a partition length value of H/N, said ith region comprising W columns and H/N number of complete rows; and

b. incrementing said index variable i and repeating step a if said index variable i is less than N.

10. The method of claim 9 wherein said ith region further comprises an overlap area which is shared with a i+1 processing unit.

11. The method of claim 9 wherein the ith region of said image is assigned to a ith processing means, said processing means comprising a processor, a local memory and a means for receiving said ith region of said image.

12. The method of claim 9 wherein each of said regions comprises blocks of luminance and chrominance information.

13. The method of claim 9 wherein said processing comprises said image.

14. The method of claim 9 wherein said image comprises one in a plurality of images.

15. The method of claim 9 wherein said processing comprises compressing said plurality of images.

16. The method of claim 9 wherein said processing comprises decompressing said image.