Apparatus and method of encoding/decoding a coded block pattern

• US 6,571,019 B1
• Filed: 05/07/1999
• Issued: 05/27/2003
• Est. Priority Date: 10/26/1995
• Status: Expired due to Term

• Current Assignee: Pantech Incorporated
• Original Assignee: Hyundai Curitel ,inc
• Inventors: Chun, Sung-Moon, Moon, Joo-Hee, Park, Kwang-Hoon, Lee, Jin-Hak, Kim, Jae-Kyoon, Chung, Jae Won
• Primary Examiner(s): Mehta, Bhavesh M .
• Assistant Examiner(s): PATEL, KANJIBHAI B
• Application Number:
  US09/306,743
• Time in Patent Office: 1,481 Days
• Field of Search: 382/236, 382/239, 382/241, 382/242, 382/243, 382/246, 382/245, 382/250, 382/251, 382/266, 382/276, 382/305, 375/240.03, 375/240.18, 375/240.2, 375/240.23, 375/240.24, 341/67, 341/65, 358/539, 348/14.13
• US Class Current: 382/246
• CPC Class Codes: G06T 9/20 Contour coding, e.g. using detection of edges
• CPC Class Codes: H04N 19/14 Coding unit complexity, e.g. amount of activity or edge presence estimation H04N19/146 takes precedence
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/196 being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters processing of motion vectors H04N19/513
• CPC Class Codes: H04N 19/20 using video object coding
• CPC Class Codes: H04N 19/463 by compressing encoding parameters before transmission
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards

Abstract

The present invention selectively applies one of VLC tables stored in a memory for encoding a coded block pattern of a macroblock according to the number of blocks having an object within the macroblock, the number of blocks obtained using shape information, thereby reducing the amount of data transmitted and increasing coding efficiency.

The present invention also selectively applies one of VLD tables stored in a memory for decoding a coded block pattern of a macroblock according to the number of blocks having an object within the macroblock, the number of blocks obtained using shape information.

Claims

1. In an object-based video coding system comprising a shape information encoding unit for encoding input shape information and providing reconstructed shape information and a texture information encoding unit including a transform unit, quantizer, scanning unit, and variable length coding (VLC) unit for encoding input texture information, a coded block pattern encoding apparatus comprising:

a non-transparent block counter for detecting the number of non-transparent blocks within the macroblock using said input reconstructed shape information and generating first and second switching control signals according to the detected number of non-transparent blocks;

a coded block pattern decision unit for generating numerical information for reading the coded block pattern according to the number of non-transparent blocks based upon said input reconstructed shape information;

a first switch for coupling information generated from said coded block pattern decision unit to one of a plurality of paths according to the first switching control signal generated from said non-transparent block counter;

a VLC table memory for providing the encoded coded block pattern according to information obtained through the first switch;

a second switch for coupling the coded block pattern generated from said VLC table memory to an output path according to the second switching control signal generated from said non-transparent block counter; and

multiplexing means for multiplexing the coded block pattern generated from said coded block pattern decision and encoding means and texture information generated from said VLC unit to provide an output.

2. The apparatus according to claim 1, wherein said VLC table memory comprises:

a first sub-memory for storing a VLC table corresponding to a macroblock having one block where an object is present and providing a coded block pattern corresponding to the macroblock having one block where the object is present;

a second sub-memory for storing a VLC table corresponding to a macroblock having two blocks where an object is present and providing a coded block pattern corresponding to the macroblock having two blocks where the object is present;

a third sub-memory for storing a VLC table corresponding to a macroblock having three blocks where an object is present and providing a coded block pattern corresponding to the macroblock having three blocks where the object is present; and

a fourth sub-memory for storing a VLC table corresponding to a macroblock having four blocks where an object is present and providing a coded block pattern corresponding to the macroblock having four blocks where the object is present.

3. In an object-based video decoding system comprising a shape information decoding unit for decoding an input shape bitstream and providing a reconstructed shape bitstream and a texture information decoding unit including a demultiplexer, variable length decoding (VLD) unit, inverse scanning, inverse quantizer, and inverse transform unit for decoding an input texture bitstream, a coded block pattern decoding apparatus comprising:

a non-transparent block counter for detecting the number of non-transparent blocks within the macroblock to be decoded using said reconstructed shape information and generating first and second switching control signals according to the detected number of non-transparent blocks;

a first switch for controlling a path of the coded block pattern output from said demultiplexer according to the first switching control signal generated from said non-transparent block counter;

a VLD table memory for providing a coded block pattern decoded according to VLD tables having different length using a signal applied via the first switch as an address; and

a second switch for coupling the coded block pattern generated from said VLD table memory to an output path according to the second switching control signal generated from said non-transparent block counter; and

switching means for allowing or not allowing the texture bitstream output from said demultiplexer to be transmitted to said VLD unit according to the switching control signal output from said coded block pattern decoding means.

4. The apparatus according to claim 3, wherein said non-transparent block counter detects blocks having object information using said reconstructed shape information, said block having a predetermined size in the macroblock decoded, counts the blocks having the object information, and generates said first and second switching control signals according to the counted value.

5. The apparatus according to claim 3, wherein said VLD table memory comprises:

a first sub-memory for storing a VLD table corresponding to a macroblock having one block where an object is present and providing a coded block pattern corresponding to the macroblock having one block where the object is present;

a second sub-memory for storing a VLD table corresponding to a macroblock having two blocks where an object is present and providing a coded block pattern corresponding to the macroblock having two blocks where the object is present;

a third sub-memory for storing a VLD table corresponding to a macroblock having three blocks where an object is present and providing a coded block pattern corresponding to the macroblock having three blocks where the object is present; and

a fourth sub-memory for storing a VLD table corresponding to a macroblock having four blocks where an object is present and providing a coded block pattern corresponding to the macroblock having four blocks where the object is present.

6. In an object-based video coding system and object based decoding system, in which the coding system comprises a shape information encoding unit for encoding input shape information and providing reconstructed shape information and a texture information encoding unit including a transform unit, a quantizer, a scanning unit, and a variable length coding (VLC) unit for encoding input texture information, and a coded block pattern encoding apparatus and, the decoding system comprises a shape information decoding unit for decoding an input shape bitstream and providing a reconstructed shape bitstream and a texture information decoding unit including a demultiplexer, a variable length decoding (VLD) unit, an inverse scanning, an inverse quantizer, and an inverse transform unit for decoding an input texture bitstream, and a coded block pattern decoding apparatus, the coding system comprising:

a coding non-transparent block counter for detecting the number of non-transparent blocks within the macroblock using said input reconstructed shape information and generating first and second switching control signals according to the detected number of non-transparent blocks;

a coded block pattern decision unit for generating numerical information for reading the coded block pattern according to the number of non-transparent blocks based upon said input reconstructed shape information;

a first switch for coupling information generated from said coded block pattern decision unit to one of a plurality of paths according to the first switching control signal generated from said non-transparent block counter;

a VLC table memory for providing the encoded coded block pattern according to information obtained through the first switch;

a second switch for coupling the coded block pattern generated from said VLC table memory to an output path according to the second switching control signal generated from said non-transparent block counter; and

multiplexing means for multiplexing the coded block pattern generated from said coded block pattern decision and encoding means and texture information generated from said VLC unit to provide an output.

7. The system according to claim 6, wherein the decoding system further comprises:

a decoding non-transparent block counter for detecting the number of non-transparent blocks within the macroblock to be decoded using said reconstructed shape information and generating third and fourth switching control signals according to the detected number of non-transparent blocks;

a third switch for controlling a path of the coded block pattern output from said demultiplexer according to the third switching control signal generated from said non-transparent block counter;

a VLD table memory for providing a coded block pattern decoded according to VLD tables having different length using a signal applied via the third switch as an address;

a fourth switch for coupling the coded block pattern generated from said VLD table memory to an output path according to the fourth switching control signal generated from said non-transparent block counter; and

switching means for allowing or not allowing the texture bitstream output from said demultiplexer to be transmitted to said VLD unit according to the switching control signal output from said coded block pattern decoding means.

8. In an object-based video coding system and object based decoding system, in which the coding system comprises a shape information encoding unit for encoding input shape information and providing reconstructed shape information and a texture information encoding unit including a transform unit, a quantizer, a scanning unit, and a variable length coding (VLC) unit for encoding input texture information, and a coded block pattern encoding apparatus and, the decoding system comprises a shape information decoding unit for decoding an input shape bitstream and providing a reconstructed shape bitstream and a texture information decoding unit including a demultiplexer, a variable length decoding (VLD) unit, an inverse scanning, an inverse quantizer, and an inverse transform unit for decoding an input texture bitstream, and a coded block pattern decoding apparatus, the decoding system comprising:

a decoding non-transparent block counter for detecting the number of non-transparent blocks within the macroblock to be decoded using said reconstructed shape information and generating third and fourth switching control signals according to the detected number of non-transparent blocks;

a third switch for controlling a path of the coded block pattern output from said demultiplexer according to the third switching control signal generated from said non-transparent block counter;

a VLD table memory for providing a coded block pattern decoded according to VLD tables having different length using a signal applied via the third switch as an address;

a fourth switch for coupling the coded block pattern generated from said VLD table memory to an output path according to the fourth switching control signal generated from said non-transparent block counter; and

switching means for allowing or not allowing the texture bitstream output from said demultiplexer to be transmitted to said VLD unit according to the switching control signal output from said coded block pattern decoding means.

9. The system of claim 8, wherein the coding system further comprises:

a coding non-transparent block counter for detecting the number of non-transparent blocks within the macroblock using said input reconstructed shape information and generating first and second switching control signals according to the detected number of non-transparent blocks;

a coded block pattern decision unit for generating numerical information for reading the coded block pattern according to the number of non-transparent blocks based upon said input reconstructed shape information;

a first switch for coupling information generated from said coded block pattern decision unit to one of a plurality of paths according to the first switching control signal generated from said non-transparent block counter;

a VLC table memory for providing the encoded coded block pattern according to information obtained through the first switch; and

a second switch for coupling the coded block pattern generated from said VLC table memory to an output path according to the second switching control signal generated from said non-transparent block counter; and

multiplexing means for multiplexing the coded block pattern generated from said coded block pattern decision and encoding means and texture information generated from said VLC unit to provide an output.