MOVING-PICTURE COMPRESSION-ENCODING APPARATUS

• US 20090110056A1
• Filed: 10/20/2008
• Published: 04/30/2009
• Est. Priority Date: 10/26/2007
• Status: Active Grant

• Current Assignee: KDDI Corporation
• Original Assignee: KDDI Corporation
• Inventors: MIYAJI, Satoshi, TAKISHIMA, Yasuhiro
• Granted Patent: US 8,660,183 B2
• Time in Patent Office: Days
• US Class Current: 375/240.10
• CPC Class Codes: H04N 19/103 Selection of coding mode or of prediction mode
• CPC Class Codes: H04N 19/105 Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/147 according to rate distortion criteria rate-distortion as a criterion for motion estimation H04N19/567
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/157 Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

Re-encoding information indicating whether or not an input moving picture has been compression-encoded is provided to a mode determining unit. The mode determining unit determines an optimal encoding mode for the input moving picture, out of a plurality of encoding modes. The mode determining operation is controlled by the re-encoding information. According to a mode determination result of the mode determining unit, a prediction error value corresponding to the determined mode is selected by a selection switch, and then, an encoding process is performed. As the re-encoding information, a predetermined value, a bit rate, and a quantization parameter, etc., could be provided.

Claims

1. A moving-picture compression-encoding apparatus that selectively compression-encodes a moving picture that has not been compression-encoded and a moving picture obtained by decoding a compression-encoded moving picture, comprising:

a mode determining means that determines which mode, out of a plurality of encoding modes, is used to encode an input moving picture, by using a mode determining coefficient that serves as a threshold for a mode determination;

an encoding means that performs an encoding process on the input moving picture with the mode determined by the mode determining means;

an acquiring means that acquires re-encoding information indicating whether or not the input moving picture has been compression-encoded; and

a changing means that changes a mode determining operation in the mode determining means, when the re-encoding information acquired by the acquiring means is indicating that the input moving picture has been compression-encoded.

2. The moving-picture compression-encoding apparatus according to claim 1, wherein the changing means changes the mode determining operation by changing a coupling coefficient in rate-distortion optimization control.

3. The moving-picture compression-encoding apparatus according to claim 1, wherein the changing means changes the mode determining operation by changing an amount of side information in the mode determining means.

4. The moving-picture compression-encoding apparatus according to claim 1, wherein the re-encoding information acquired by the acquiring means has a value indicating a level of influence of encoding noise incurred as a result of the compression encoding, and the changing means changes the mode determining operation according to the value.

5. The moving-picture compression-encoding apparatus according to claim 2, wherein the re-encoding information acquired by the acquiring means has a value indicating a level of influence of encoding noise incurred as a result of the compression encoding, and the changing means changes the mode determining operation according to the value.

6. The moving-picture compression-encoding apparatus according to claim 3, wherein the re-encoding information acquired by the acquiring means has a value indicating a level of influence of encoding noise incurred as a result of the compression encoding, and the changing means changes the mode determining operation according to the value.

7. The moving-picture compression-encoding apparatus according to claim 4, wherein the acquiring means comprises a means that calculates a bit rate by observing a number of bits per unit time from a bit stream when the input moving picture is encoded, and provides the bit rate calculated thereby as the re-encoding information.

8. The moving-picture compression-encoding apparatus according to claim 5, wherein the acquiring means comprises a means that calculates a bit rate by observing a number of bits per unit time from a bit stream when the input moving picture is encoded, and provides the bit rate calculated thereby as the re-encoding information.

9. The moving-picture compression-encoding apparatus according to claim 6, wherein the acquiring means comprises a means that calculates a bit rate by observing a number of bits per unit time from a bit stream when the input moving picture is encoded, and provides the bit rate calculated thereby as the re-encoding information.

10. The moving-picture compression-encoding apparatus according to claim 4, wherein the acquiring means comprises a means that resolves a bit rate by taking out an information field indicating a bit rate from a bit stream when the input moving picture is encoded, and provides the bit rate taken out thereby as the re-encoding information.

11. The moving-picture compression-encoding apparatus according to claim 5, wherein the acquiring means comprises a means that resolves a bit rate by taking out an information field indicating a bit rate from a bit stream when the input moving picture is encoded, and provides the bit rate taken out thereby as the re-encoding information.

12. The moving-picture compression-encoding apparatus according to claim 6, wherein the acquiring means comprises a means that resolves a bit rate by taking out an information field indicating a bit rate from a bit stream when the input moving picture is encoded, and provides the bit rate taken out thereby as the re-encoding information.

13. The moving-picture compression-encoding apparatus according to claim 4, wherein the acquiring means comprises a means that estimates an encoding noise amount by observing a quantization parameter per frame from a bit stream when the input moving picture is encoded, and provides the encoding noise amount estimated thereby as the re-encoding information.

14. The moving-picture compression-encoding apparatus according to claim 5, wherein the acquiring means comprises a means that estimates an encoding noise amount by observing a quantization parameter per frame from a bit stream when the input moving picture is encoded, and provides the encoding noise amount estimated thereby as the re-encoding information.

15. The moving-picture compression-encoding apparatus according to claim 6, wherein the acquiring means comprises a means that estimates an encoding noise amount by observing a quantization parameter per frame from a bit stream when the input moving picture is encoded, and provides the encoding noise amount estimated thereby as the re-encoding information.