Picture signal encoding method and apparatus, picture signal transmitting method, picture signal decoding method and apparatus and recording medium

• US 6,256,349 B1
• Filed: 12/24/1996
• Issued: 07/03/2001
• Est. Priority Date: 12/28/1995
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yagasaki, Yoichi, Suzuki, Teruhiko
• Primary Examiner(s): Kelley, Chris
• Assistant Examiner(s): PHILIPPE, GIMS S
• Application Number:
  US08/772,894
• Time in Patent Office: 1,652 Days
• Field of Search: H04/N.592, H04/N.712, H04/B.166, 348/403, 348/409, 348/410, 348/411, 348/412, 348/413, 348/416, 348/398, 386/68, 386/109, 340/825, 382/239, 382/244, 382/240, 714/736, 375/240.18
• US Class Current: 375/240.18
• CPC Class Codes: H04N 19/45 performing compensation of the inverse transform mismatch, e.g. Inverse Discrete Cosine Transform [IDCT] mismatch
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

There is provided a picture signal encoding method in which a signal obtained on processing picture signals with encoding accompanying real-number calculations and the resulting quantized signal is outputted, locally decoded data of the encoded data and data prevailing prior to execution of the real-number calculations are compared to each other to find a difference signal. This difference signal is added to decoded data for signal correction for realizing reversible encoding and the encoding/decoding of high-precision picture signals. Also provided are a corresponding signal encoding apparatus, a picture signal transmitting method, a picture signal decoding method and apparatus and a recording medium having thereon recorded signal decodable by the picture decoding apparatus

Claims

1. A picture signal encoding method for use with an encoding apparatus, said method comprising the steps of:

processing an input picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for processing the predicted picture signal with encoding accompanying real-number calculations for generating encoded data;

supplying an encoded signal corresponding to the encoded data to a first transmission buffer;

locally decoding the encoded data for generating locally decoded data;

determining a difference between the locally decoded data and picture data prevailing prior to performing real-number calculations, said difference being representative of information lost from the input picture signal; and

supplying a difference signal representative of said difference to a second transmission buffer;

wherein the encoded signal and said difference signal are usable with a decoding apparatus such that the encoded data is decoded in a manner similar to that performed in the locally decoding step so as to obtain second decoded data with lost information corresponding to the information lost during the encoding method and such that said difference is combined with the second decoded data so as to obtain the picture data.

2. The picture signal encoding method as claimed in claim 1 wherein said real-number calculations consist in discrete cosine transform.

3. The picture signal encoding method as claimed in claim 1 wherein said locally decoded data is data directly following the real-number calculations.

4. The picture signal encoding method as claimed in claim 1 wherein said encoding is the processing of predictive encoding followed by real-number calculations and wherein

said locally decoded data is data restored after addition thereto of a prediction signal of predictive encoding.

5. The picture signal encoding method as claimed in claim 1 wherein said encoding is the processing of performing real-number calculations on the difference between the representative value data determined from one pre-set block of the input picture data to another and the original input picture data.

6. A picture signal encoding apparatus comprising:

means for processing an input picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for processing the predicted picture signal with encoding accompanying real-number calculations for generating encoded data;

means for supplying an encoded signal corresponding to the encoded data to a first transmission buffer;

means for locally decoding the encoded data for generating locally decoded data;

means for determining a difference between the locally decoded data and picture data prevailing prior to performing the real-number calculations, said difference being representative of information lost from the input picture signal; and

means for supplying a difference signal representative of said difference to a second transmission buffer;

wherein the encoded signal and said difference signal are usable with a decoding apparatus such that the encoded data is decoded in a manner similar to that performed in the locally decoding step so as to obtain second decoded data with lost information corresponding to the information lost during the operations performed by the encoding apparatus and such that said difference is combined with the second decoded data so as to obtain the picture data.

7. The picture signal encoding apparatus as claimed in claim 6 wherein said real-number calculations consist in discrete cosine transform.

8. The picture signal encoding apparatus as claimed in claim 6 wherein said locally decoded data is data directly following the real-number calculations.

9. The picture signal encoding apparatus as claimed in claim 6 wherein said encoding is the processing of predictive encoding followed by real-number calculations and wherein

said locally decoded data is data restored after addition thereto of a prediction signal of predictive encoding.

10. The picture signal encoding apparatus as claimed in claim 6 wherein said encoding is the processing of performing real-number calculations on the difference between the representative value data determined from one pre-set block of the input picture data to another and the original input picture data.

11. A picture signal transmitting method for use with a transmitting apparatus, said method comprising the steps of:

processing an input picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for processing the predicted picture signal with encoding accompanying real-number calculations for generating encoded data;

supplying an encoded signal corresponding to the encoded data to a first transmission buffer for storage thereat;

obtaining the encoded signal stored in the first transmission buffer and transmitting the same;

locally decoding the encoded data for generating locally decoded data;

determining a difference between the locally decoded data and picture data prevailing prior to performing the real-number calculations, said difference being representative of information lost from the input picture signal;

supplying a difference signal representative of said difference to a second transmission buffer for storing thereat; and

obtaining the difference signal stored in the second transmission buffer and transmitting the same;

wherein the transmitted encoded signal and transmitted difference signal are usable with a receiving apparatus such that said transmitted encoded data is decoded in a manner similar to that performed in the locally decoding step so as to obtain second decoded data with lost information corresponding to the information lost during the transmitting method and such that said transmitted difference signal is processed so as to obtain said difference which is combined with the second decoded data so as to obtain the picture data.

12. The picture signal transmitting method as claimed in claim 11 wherein said real-number calculations consist in discrete cosine transform.

13. The picture signal transmitting method as claimed in claim 11 wherein said locally decoded data is data directly following the real-number calculations.

14. The picture signal transmitting method as claimed in claim 11 wherein said encoding is the processing of predictive encoding followed by real-number calculations and wherein

said locally decoded data is data restored after addition thereto of a prediction signal of predictive encoding.

15. The picture signal transmitting method as claimed in claim 11 wherein said encoding is the processing of performing real-number calculations on the difference between the representative value data determined from one pre-set block of the input picture data to another and the original input picture data.

16. A recording medium decodable by a decoding apparatus in which the recording medium has recorded signals decodable by said decoding apparatus, said recorded signals including an encoded signal and difference data, said recorded signal being recorded by a method comprising the steps of:

processing an input picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bidirectional prediction in accordance with a control signal to form a predicted picture signal and for processing the predicted picture signal with encoding accompanying real-number calculations for generating encoded data;

supplying an encoded signal corresponding to the encoded data to a first transmission buffer;

locally decoding the encoded data for generating locally decoded data;

determining a difference between the locally decoded data and picture data prevailing prior to performing the real-number calculations, said difference being representative of information lost from the input picture signal; and

supplying a difference signal representative of said difference to a second transmission buffer;

wherein the decoding apparatus is adaptable to decode the encoded data in a manner similar to that performed in the locally decoding step so as to obtain second decoded data with lost information corresponding to the information lost during the recording method and to combine said difference with the second decoded data so as to obtain the picture data.

17. A picture signal decoding method in which original picture data is restored by decoding an encoded signal obtained by processing input picture signals for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for processing the predicted picture signal with accompanying real-number calculations and difference data signals obtained from a difference between locally decoded data of encoded data corresponding to the encoded signal and picture data prevailing prior to performing said real-number calculations, said difference being representative of information lost from the input picture signals, comprising the steps of:

receiving said encoded signal at a first reception buffer;

decoding the received encoded data by decoding as a counterpart of the encoding for generating decoded data with lost information which corresponds to the information lost prior to performing the decoding method;

receiving the difference data signals at a second reception buffer; and

summing a signal corresponding to the received difference data signals to said decoded data so as to obtain the original picture data.

18. The picture signal decoding method as claimed in claim 17 wherein said decoding includes at least discrete cosine transform.

19. A picture signal decoding apparatus in which original picture data is restored by decoding an encoded signal obtained by processing input picture signals for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for processing the predicted picture signal with accompanying real-number calculations and difference data signals obtained from a difference between locally decoded data of encoded data corresponding to the encoded signal and picture data prevailing prior to performing said real-number calculations, said difference being representative of information lost from the input picture signals, comprising:

means for receiving said encoded signal at a first reception buffer;

means for decoding the received encoded data by decoding as a counterpart of the encoding for generating decoded data with lost information which corresponds to the information lost prior to operations performed by the decoding apparatus;

means for receiving the difference data signals at a second reception buffer; and

means for summing a signal corresponding to the received difference data signals to said decoded data so as to obtain the original picture data.

20. The picture signal decoding apparatus as claimed in claim 19 wherein said decoding includes at least discrete cosine transform.

21. A picture signal encoding method for use with an encoding apparatus, said method comprising the steps of:

processing a picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for encoding the predicted picture signal so as to obtain encoded data, in which said encoding includes performing a discrete cosine transform;

supplying an encoded signal corresponding to the encoded data to a first transmission buffer;

locally decoding the encoded data to form locally decoded data;

determining a difference between the locally decoded data and said picture signal, said difference being representative of information lost from said picture signal; and

supplying a difference signal representative of said difference to a second transmission buffer;

wherein the processing and encoding step, the encoded data supplying step, the locally decoding step, the difference signal supplying step and the determining step are performed by said encoding apparatus.

22. A picture signal encoding apparatus comprising:

means for processing a picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for encoding the predicted picture signal so as to obtain encoded data, in which the encoding means performs a discrete cosine transform;

means for supplying an encoded signal corresponding to the encoded data to a first transmission buffer;

means for locally decoding the encoded data to form locally decoded data;

means for determining a difference between the locally decoded data and said picture signal, said difference being representative of information lost from said picture signal; and

means for supplying a difference signal representative of said difference to a second transmission buffer.

23. A picture signal transmitting method for use with a transmitting apparatus, said method comprising:

processing a picture signal for one of intra-picture prediction, forward prediction, backward prediction, and bi-directional prediction in accordance with a control signal to form a predicted picture signal and for encoding the predicted picture signal so as to obtain encoded data, in which said encoding includes performing a discrete cosine transform;

supplying an encoded signal corresponding to the encoded data to a first transmission buffer for storage thereat;

obtaining the encoded signal stored in the first transmission buffer and transmitting the same;

locally decoding the encoded data to form locally decoded data;

determining a difference between the locally decoded data and said picture signal, said difference being representative of information lost from said picture signal;

supplying a difference signal representative of said difference to a second transmission buffer for storage thereat; and

obtaining the difference signal stored in the second transmission buffer and transmitting the same;

wherein the processing and encoding step, the encoded data supplying step, the locally decoding step, the determining step and the difference signal supplying step are performed in said transmitting apparatus.