Video coding and video decoding apparatus

• US 6,546,138 B1
• Filed: 08/25/1999
• Issued: 04/08/2003
• Est. Priority Date: 09/29/1995
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Watanabe, Toshiaki, Ida, Takashi, Yamaguchi, Noboru, Kuratate, Takaaki
• Primary Examiner(s): Patel, Jayanti K.
• Assistant Examiner(s): Do, Anh Hong
• Application Number:
  US09/382,771
• Time in Patent Office: 1,322 Days
• Field of Search: 382/232, 348/390, 375/240.25
• US Class Current: 382/232
• CPC Class Codes: G06T 3/40 Scaling of whole images or parts thereof, e.g. expanding or contracting
• CPC Class Codes: G06T 3/4023 based on decimating pixels or lines of pixels; based on inserting pixels or lines of pixels
• CPC Class Codes: H04N 19/20 using video object coding
• CPC Class Codes: H04N 19/29 involving scalability at the object level, e.g. video object layer [VOL]
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution

Abstract

A video encoding apparatus is provided with a resolution converting section, an encoding section, and a transmitting section. The resolution converting section enlarges or reduces a binary picture which represents the shape of an object. The encoding section encodes a binary picture reduced by the resolution converting section. The reduction ratio used by the resolution converting section is encoded, and the transmitting section transmits this encoded reduction ratio along with encoded data on the binary picture. The amount of encoded data produced from the encoding section is controlled by changing the enlargement/reduction ratio used by the resolution converting section.

Claims

1. A computer system for encoding pictures, comprising:

a first resolution converter configured to reduce an alpha-map signal to control an amount of generated codes of the alpha-map signal by changing a resolution conversion according to a reduction ratio setting information signal, the alpha map signal indicating information for discriminating a picture between an object region and a background region;

an alpha-map encoder configured to encode a reduced alpha-map signal output from said first resolution converter and the reduction ratio setting information signal to output coded alpha-map data and coded reduction ratio setting information data;

a second resolution converter configured to enlarge the reduced alpha-map signal at an enlargement ratio to return the reduced alpha-map signal to an original size and output an enlarged alpha-map signal;

a multiplexer which multiplexes the coded alpha-map data and the coded reduction ratio setting information data; and

a video encoder configured to encode, in accordance with the enlarged alpha-map signal, a picture corresponding to the enlarged alpha-map signal.

2. A computer system according to claim 1, wherein:

the first resolution converter is configured to reduce the alpha-map signal which is a binary picture signal.

3. A computer system according to claim 1, further comprising:

a camera which outputs the picture encoded by the video encoder.

4. A computer system according to claim 1, further comprising:

a transmitter configured to transmit the picture which has been encoded by the video encoder.

5. A computer system according to claim 4, wherein:

said transmitter is a radio transmitter.

6. A computer system according to claim 1, wherein:

said transmitter outputs a signal on a line as a coded bit stream.

7. A computer system according to claim 1, further comprising:

a person computer.

8. A computer system for encoding pictures, comprising:

a first resolution conversion means for reducing an alpha-map signal to control an amount of generated codes of the alpha-map signal by changing a resolution conversion according to a reduction ratio setting information signal, the alpha map signal indicating information for discriminating a picture between an object region and a background region;

an alpha-map encoding means for encoding a reduced alpha-map signal output from said first resolution conversion means and the reduction ratio setting information signal to output coded alpha-map data and coded reduction ratio setting information data;

a second resolution conversion means for enlarging the reduced alpha-map signal at an enlargement ratio to return the reduced alpha-map signal to an original size and output an enlarged alpha-map signal;

multiplexing means for multiplexing the coded alpha-map data and the coded reduction ratio setting information data; and

video encoding means for encoding, in accordance with the enlarged alpha-map signal, a picture corresponding to the enlarged alpha-map signal.

9. A computer system according to claim 8, wherein:

the first resolution conversion means is for reducing the alpha-map signal which is a binary picture signal.

10. A computer system according to claim 8, further comprising:

image obtaining means for outputting the picture encoded by the video encoder.

11. A computer system according to claim 8, further comprising:

a transmission means for transmitting the picture which has been encoded by the video encoder.

12. A computer system according to claim 11, wherein:

said transmission means comprises a radio transmission means.

13. A computer system according to claim 8, wherein:

said transmission means outputs a signal on a line as a coded bit stream.

14. A computer system according to claim 8, further comprising:

a person computer means for computer.

15. A computer system for decoding pictures, comprising:

a demultiplexer configured to demultiplex a coded signal into an alpha-map signal for discriminating a picture between an object region and a background region, and a coded picture signal, the alpha-map signal including a reduction ratio setting information signal for reducing an amount of generated codes of the alpha map signal;

a decoder, configured to decode the alpha-map signal which has been demultiplexed by the demultiplexer, to separate the alpha-map signal into a decoded alpha-map and reduction ratio setting information;

a resolution converter configured to enlarge the decoded alpha-map signal in accordance with the reduction ratio setting information; and

a picture decoder configured to decode the coded picture signal in accordance with the enlarged alpha-map signal and to output a reconstructed picture signal.

16. A computer system according to claim 15, wherein:

the demultiplexer is configured to demultiplex the coded signal into the alpha-map signal which is a binary signal and the coded picture signal.

17. A computer system for decoding pictures, comprising:

a demultiplexing means for demultiplexing a coded signal into an alpha-map signal for discriminating a picture between an object region and a background region, and a coded picture signal, the alpha-map signal including a reduction ratio setting information signal for reducing an amount of generated codes of the alpha map signal;

means for decoding the alpha-map signal which has been demultiplexed by the demultiplexer, to separate the alpha-map signal into a decoded alpha-map and reduction ratio setting information;

resolution conversion means for enlarging the decoded alpha-map signal in accordance with the reduction ratio setting information; and

a picture decoding means for decoding the coded picture signal in accordance with the enlarged alpha-map signal and outputting a reconstructed picture signal.

18. A computer system according to claim 17, wherein:

the demultiplexing means demultiplexes the coded signal into the alpha-map signal which is a binary signal and the coded picture signal.

19. A computer system for encoding and decoding pictures, comprising:

a first computer including;

a first resolution converter configured to reduce an alpha-map signal to control an amount of generated codes of the alpha-map signal by changing a resolution conversion according to a reduction ratio setting information signal, the alpha map signal indicating information for discriminating a picture between an object region and a background region;

an alpha-map encoder configured to encode a reduced alpha-map signal output from said first resolution converter and the reduction ratio setting information signal to output coded alpha-map data and coded reduction ratio setting information data;

a second resolution converter configured to enlarge the reduced alpha-map signal at an enlargement ratio to return the reduced alpha-map signal to an original size and output an enlarged alpha-map signal;

a first multiplexer which multiplexes the coded alpha-map data and the coded reduction ratio setting information data and outputs a multiplexed alpha-map signal;

a video encoder configured to encode, in accordance with the enlarged alpha-map signal, a picture corresponding to the enlarged alpha-map signal and to output an encoded picture signal;

a second multiplexer which multiplexes said multiplexed alpha-map signal and the encoded picture signal and outputs a second multiplexed signal, and

a second computer including;

a first demultiplexer configured to demultiplex the second multiplexed signal into the alpha-map signal for discriminating a picture between an object region and a background region, and the encoded picture signal, the alpha-map signal including the reduction ratio setting information signal;

a second demulitplexer, configured to decode the alpha-map signal which has been demultiplexed by the first demultiplexer, to separate the alpha-map signal into a decoded alpha-map signal and the reduction ratio setting information signal;

a resolution converter configured to enlarge the decoded alpha-map signal in accordance with the reduction ratio setting information signal; and

a picture decoder configured to decode the encoded picture signal in accordance with the enlarged alpha-map signal and to output a reconstructed picture signal.

20. A computer system for encoding and decoding pictures, comprising:

a first computer including;

a first resolution conversion means for reducing an alpha-map signal to control an amount of generated codes of the alpha-map signal by changing a resolution conversion according to a reduction ratio setting information signal, the alpha map signal indicating information for discriminating a picture between an object region and a background region;

alpha-map encoding means for encoding a reduced alpha-map signal output from said first resolution conversion means and the reduction ratio setting information signal to output coded alpha-map data and coded reduction ratio setting information data;

a second resolution conversion means for enlarging the reduced alpha-map signal at an enlargement ratio to return the reduced alpha-map signal to an original size and output an enlarged alpha-map signal;

first multiplexing means for multiplexing the coded alpha-map data and the coded reduction ratio setting information data and outputting a multiplexed alpha-map signal;

video encoding means for encoding, in accordance with the enlarged alpha-map signal, a picture corresponding to the enlarged alpha-map signal and to output an encoded picture signal;

second multiplexing means for multiplexing said multiplexed alpha-map signal and the encoded picture signal and outputting a second multiplexed signal, and

a second computer including;

first demultiplexing means for demultiplexing the second multiplexed signal into the alpha-map signal for discriminating a picture between an object region and a background region, and the encoded picture signal, the alpha-map signal including the reduction ratio setting information signal;

second demulitplexing means for decoding the alpha-map signal which has been demultiplexed by the first demultiplexer, and separating the alpha-map signal into a decoded alpha-map signal and the reduction ratio setting information signal;

resolution conversion means for enlarging the decoded alpha-map signal in accordance with the reduction ratio setting information signal; and

picture decoder means for decoding the encoded picture signal in accordance with the enlarged alpha-map signal and outputting a reconstructed picture signal.