Framework for quality-aware video optimization

Patent metadata

Field	Value
Publication number	US-9894361-B2
Application number	US-75195110-A
Country	US
Kind code	B2
Filing date	Mar 31, 2010
Priority date	Mar 31, 2009
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A computer-implemented method includes receiving an encoded video frame, decompressing the received encoded video frame, extracting a first quantization parameter (QP) from the decompressed video frame, and acquiring a delta QP based on the first QP. The method also includes acquiring a second QP based on the delta QP and the first QP, compressing the decompressed video frame based on the second QP, and providing the compressed video frame. The first QP corresponds to quantization settings originally used for compressing the encoded video frame. And the second QP corresponds to quantization settings for compressing the decompressed video frame.

First claim

What is claimed is:

1. A computer-implemented method comprising:
receiving an encoded video frame;
decompressing the received encoded video frame;
extracting a first quantization parameter (QP) from the decompressed video frame, wherein the first QP corresponds to quantization settings originally used for compressing the encoded video frame;
acquiring a delta QP based on the first QP;
acquiring an inflation adjustment based on a comparison between total byte size of frames previously decompressed and total byte size of the frames after being previously compressed, wherein the received encoded video frame and the frames previously decompressed are part of a sequence including a plurality of video frames;
acquiring a second QP based on the delta QP, the first QP, and the inflation adjustment, wherein the second QP corresponds to quantization settings for compressing the decompressed video frame;
compressing the decompressed video frame based on the acquired second QP; and
providing the compressed video frame.

2. The method of claim 1 , further comprising:
determining whether a compression format of the received encoded video frame is different from a compression format to be used for compressing the decompressed video frame;
converting, based on the determination, the first QP from an input QP scale into an output QP scale, wherein the input QP scale corresponds to the compression format of the received encoded video frame, and the output QP scale corresponds to the compression format to be used for compressing the decompressed video frame; and
acquiring the second QP based on the converted first QP and the delta QP.

3. The method of claim 2 , wherein converting the first QP is further based on a mapping between the input QP scale and the output QP scale.

4. The method of claim 1 , wherein acquiring the delta QP is further based on a mapping between the first QP and the delta QP.

5. The method of claim 1 , wherein acquiring the delta QP comprises:
choosing, if a value of the first QP is below a threshold, a positive value for the delta QP.

6. The method of claim 1 , wherein acquiring the delta QP comprises:
choosing, if a value of the first QP is above a threshold, a negative value for the delta QP.

7. The method of claim 1 , further comprising:
acquiring a quality degradation offset for controlling amount of video quality degradation to be introduced during compression of the decompressed video frame; and
acquiring the second QP based on the quality degradation offset, the first QP, and the delta QP.

8. The method of claim 7 , wherein acquiring the quality degradation offset can be based on analysis of historical data of compressed video.

9. The method of claim 7 , wherein a default value of the quality degradation offset can be set to zero if minimal quality degradation is introduced during the compression.

10. A computer-implemented method comprising:
decompressing a received encoded video frame that is a part of a sequence including a plurality of video frames;
extracting a first quantization parameter (QP) from the decompressed video frame, wherein the first QP corresponds to quantization settings originally used for compressing the encoded video frame;
acquiring a delta QP based on the first QP;
acquiring an inflation adjustment based on a comparison between total byte size of frames previously decompressed and total byte size of the frames after being previously compressed, wherein the received encoded video frame and the frames previously decompressed are part of the sequence including a plurality of video frames;
acquiring a second QP based on the delta QP and the inflation adjustment, wherein the second QP corresponds to quantization settings for compressing the decompressed video frame; and
compressing the decompressed video frame based on the second QP.

11. The method of claim 10 , wherein the inflation adjustment is further acquired based on historical data concerning the sequence including byte size inflation that has been introduced during compression of at least some of sequence frames.

12. The method of claim 10 , wherein the historical data concerning the sequence includes byte size of at least some of sequence frames previously decompressed and byte size of the at least some of the sequence frames after previously being compressed.

13. A video optimizer comprising:
a decoder configured to decompress a received encoded video frame, wherein the decompressed video frame includes a first quantization parameter (QP) corresponding to quantization settings originally used for compressing the encoded video frame;
an inflation prevention module configured to acquire an inflation adjustment based on a comparison between total byte size of frames previously decompressed and total byte size of the frames after being previously compressed, wherein the received encoded video frame and the frames previously decompressed are part of a sequence including a plurality of video frames;
a QP adjustment module configured to obtain a delta QP based on the first QP, and to acquire a second QP based on the delta QP the first QP, and the inflation adjustment, wherein the second QP corresponds to quantization settings for compressing the decompressed video frame; and
an encoder configured to compress the decompressed video frame based on the second QP.

14. The video optimizer of claim 13 , further comprising a de-quantizer configured to decompress the received encoded video frame and to extract the first QP from the decompressed video frame.

15. The video optimizer of claim 13 , wherein the QP adjustment module is further configured to:
acquire compression format adjustment accounting for differences between a compression format of the received encoded video frame and a compression format to be used for compressing the decompressed video frame;
convert the first QP from an input QP scale into an output QP scale based on the compression format adjustment, wherein the input QP scale corresponds to the compression format of the received encoded video frame, and the output QP scale corresponds to the compression format to be used for compressing the decompressed video frame; and
obtain the second QP based on the converted first QP and the delta QP.

16. The video optimizer of claim 13 , wherein the QP adjustment module is further configured to obtain the compression format adjustment from a database containing a mapping between the input QP scale and the output QP scale.

17. The video optimizer of claim 13 , wherein the QP adjustment module is further configured to obtain the delta QP from a database containing a mapping between the first QP and the delta QP.

18. The video optimizer of claim 13 , wherein the QP adjustment module is further configured to:
acquire a quality degradation offset for controlling amount of video quality degradation to be introduced during compression of the decompressed video frame; and
obtain the second QP based on the quality degradation offset and the delta QP.

19. The video optimizer of claim 18 , wherein the QP adjustment module is further configured to acquire the quality degradation offset from a database containing historical data analysis of compressed videos.

20. The video optimizer of claim 13 , further comprising a quantizer configured to compress the decompressed video frame by applying the quantization settings represented by the second QP to compression of the decompressed video frame.

21. A video optimizer comprising:
a decoder c

Assignees

• Melnyk Miguel
• Penner Andrew
• Tidemann Jeremy
• Citrix Systems Inc

Inventors

• Melnyk Miguel
• Penner Andrew
• Tidemann Jeremy

Classifications

• H04N19/152

  by measuring the fullness of the transmission buffer · CPC title

• H04N19/172

  the region being a picture, frame or field · CPC title

• H04N19/154

  Measured or subjectively estimated visual quality after decoding, e.g. measurement of distortion (use of rate-distortion criteria H04N19/147) · CPC title

• H04N19/124 Primary

  Quantisation · CPC title

• H04N19/46

  Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence) · CPC title