Video signal encoding apparatus

• US 5,337,087 A
• Filed: 03/09/1993
• Issued: 08/09/1994
• Est. Priority Date: 01/17/1991
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Mishima, Hidetoshi
• Primary Examiner(s): Britton, Howard W.
• Application Number:
  US08/029,941
• Time in Patent Office: 518 Days
• Field of Search: 358/133, 358/135, 358/136, 358/138, 358/13, 348/405, 348/408
• US Class Current: 375/240.04
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• 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 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/88 involving rearrangement of data among different coding units, e.g. shuffling, interleaving, scrambling or permutation of pixel data or permutation of transform coefficient data among different blocks
• CPC Class Codes: H04N 19/91 Entropy coding, e.g. variable length coding [VLC] or arithmetic coding
• CPC Class Codes: H04N 19/93 Run-length coding
• CPC Class Codes: H04N 5/92 Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
• CPC Class Codes: H04N 5/9264 using transform coding

Abstract

A video signal encoding apparatus in which the number of quantization bits used in a quantizing circuit is determined on the basis of the activity index of each video block and the length of coded data or alternatively on the basis of the activity index of each video block and the number of events (each event consisting of the zero run length and nonzero value of quantized data). The video signal is encoded in a compressed form after shuffling the video blocks in such a manner that, when attention is given to any given video block, its four neighboring video blocks belong to units different from the unit to which the attention video block belong. Compression encoding of the video blocks is performed in sequence starting with the center of the screen and then proceeding toward the sides of the screen.

Claims

1. A video signal encoding apparatus for compressing and encoding a digital video signal, comprising:

block structuring means for structuring blocks each consisting of a plurality of pixels in the video signal;

transformation means for performing an orthogonal transform on each of the structure blocks to obtain a transform coefficient;

quantizing means for quantizing the transform coefficient;

encoding means for encoding the quantized data to obtain coded data; and

decision means for determining a number of quantization bits for said quantizing means on the basis of an activity index of each block and an amount of the obtained coded data.

2. A video signal encoding apparatus for compressing and encoding a digital video signal containing a chrominance signal, comprising:

block structuring means for structuring the video signal into a matrix array of blocks each consisting of a plurality of pixels;

transformation means for performing an orthogonal transform on each of the structure blocks to obtain a transform coefficient;

encoding means for encoding the obtained transform coefficient to obtain coded data; and

unit structuring means for structuring units, each unit including a plurality of blocks, prior to the orthogonal transform by said transformation means, by shuffling blocks such that any given shuffling unit and four shuffling units most adjacent to the given shuffling unit have different references, a reference of the shuffling unit being a number of blocks which the chrominance signal occupy on the screen.

3. A video signal encoding apparatus for compressing and encoding a digital video signal, comprising:

block structuring means for structuring the video signal into a matrix array of blocks each consisting of a plurality of pixels;

transformation means for performing an orthogonal transform on each of the structure blocks to obtain a transform coefficient;

encoding means for encoding the obtained transform coefficient to obtain coded data; and

unit structuring means for structuring units, each unit including a plurality of blocks, prior to the orthogonal transform by said transformation means, such that any given block and four blocks most adjacent to the given block belong to different units.

4. A video signal encoding apparatus for compressing and encoding a digital video signal, comprising:

block structuring means for structuring the video signal into a matrix array of blocks each consisting of a plurality of pixels;

transformation means for performing an orthogonal transform on each of the structured blocks to obtain a transform coefficient;

encoding means for encoding the obtained transform coefficient to obtain coded data;

unit structuring means for structuring units, each unit including a plurality of blocks, prior to the orthogonal transform by said transformation means, such that any given block and four blocks most adjacent to the given block belong to different units;

decision means for determining an order in which the blocks are to be encoded, the order within each unit being such that encoding is performed starting with blocks nearer to a center of the screen and then proceeding to blocks nearer to sides of the screen; and

control means for controlling the amount of coded data on a unit-by-unit basis.

5. A video signal encoding apparatus for compressing and encoding a digital video signal containing a chrominance signal, comprising:

block structuring means for structuring the video signal into a matrix array of blocks each consisting of a plurality of pixels;

transformation means for performing an orthogonal transform on each of the structure blocks to obtain a transform coefficient;

quantizing means for quantizing the transform coefficient;

encoding means for encoding the obtained transform coefficient to obtain coded data;

decision means for determining a number of quantization bits for said quantizing means on the basis of an activity index of each block and an amount of the obtained coded data; and

unit structuring means for structuring units, each unit including a plurality of blocks, prior to the orthogonal transform by said transformation means, by shuffling blocks such that any given shuffling unit and four shuffling units most adjacent to the given shuffling unit have different references, a reference of the shuffling unit being a number of blocks which the chrominance signal occupy on the screen.

6. A video signal encoding apparatus for compressing and encoding a digital video signal, comprising:

block structuring means for structuring the video signal into a matrix array of blocks each consisting of a plurality of pixels;

transformation means for performing an orthogonal transform on each of the structure blocks to obtain a transform coefficient;

quantizing means for quantizing the transform coefficient;

encoding means for encoding the obtained transform coefficient to obtain coded data;

decision means for determining a number of quantization bits for said quantizing means on the basis of an activity index of each block and an amount of the obtained coded data; and

unit structuring means for structuring units, each unit including a plurality of blocks, prior to the orthogonal transform by said transformation means, such that any given block and four blocks most adjacent to the given block belong to different units.

7. A video signal encoding apparatus for compressing and encoding a digital video signal, comprising:

block structuring means for structuring the video signal into a matrix array of blocks each consisting of a plurality of pixels;

transformation means for performing an orthogonal transform on each of the structured blocks to obtain a transform coefficient;

quantizing means for quantizing the transform coefficient;

encoding means for encoding the obtained transform coefficient to obtain coded data;

unit structuring means for structuring units, each unit including a plurality of blocks, prior to the orthogonal transform by said transformation means, such that any given block and four blocks most adjacent to the given block belong to different units;

decision means for determining an order in which the blocks are to be encoded, the order within each unit being such that encoding is performed starting with blocks nearer to a center of the screen and then proceeding to blocks nearer to sides of the screen and for determining a number of quantization bits for said quantizing means on the basis of an activity index of each block and an amount of the obtained coded data; and

control means for controlling the amount of the obtained coded data on a unit-by-unit basis.