Determining sample adaptive offset filter parameters

• US 10,448,009 B1
• Filed: 12/14/2017
• Issued: 10/15/2019
• Est. Priority Date: 12/14/2017
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Khsib, Ramzi
• Primary Examiner(s): Li, Tracy Y.
• Application Number:
  US15/841,962
• Time in Patent Office: 670 Days
• CPC Class Codes: H04N 19/103 Selection of coding mode or of prediction mode
• CPC Class Codes: H04N 19/117 Filters, e.g. for pre-processing or post-processing sub-band filter banks H04N19/635
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/149 by estimating the code amount by means of a model, e.g. mathematical model or statistical model
• CPC Class Codes: H04N 19/154 Measured or subjectively estimated visual quality after decoding, e.g. measurement of distortion use of rate-distortion criteria H04N19/147
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/196 being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters processing of motion vectors H04N19/513
• CPC Class Codes: H04N 19/82 involving filtering within a prediction loop

Abstract

A content streaming system and methodology facilitates the selection of sample adaptive offset filter parameters for use in a sample adaptive filter in encoding content for content streaming. Selection of the sample adaptive offset filter parameters can include multiple active parameter selection modes responsive to block-based statistics. Multiple active parameter selection modes provide increased granularity in the encoded content.

Claims

1. A system that encodes content organized into a plurality of segments, the system comprising:

one or more computing devices associated with a video packaging and origination service, wherein the video packaging and origination service is configured to;

access content for a requested segment corresponding to a received request for streaming content;

calculate an average quantization parameter per frame for the requested segment;

select one of at least three sample adaptive offset filter operating modes based on the calculated quantization parameter per frame;

determine sample adaptive offset filter parameters responsive to the selected mode;

encode the content of the requested segment according to the determined sample adaptive offset filter parameters; and

transmit the encoded content responsive to the received request for streaming content.

2. The system of claim 1 wherein selecting the one of the at least three sample adaptive filter offset operating modes responsive to the calculated quantization parameter per frame includes selecting a first adaptive operating mode corresponding to no adaptive filtering.

3. The system of claim 1 wherein selecting the one of the at least three sample adaptive filter offset operating modes responsive to the calculated quantization parameter per frame includes selecting a first adaptive filter operating mode corresponding to full adaptive filtering.

4. The system of claim 1 wherein selecting the one of the at least three sample adaptive filter offset operating modes responsive to the calculated quantization parameter per frame includes selecting a first adaptive filter operating mode corresponding to partial adaptive filtering.

5. A computer-implemented method to encode content for transmission to computing devices comprising:

receiving a request for streaming content, the streaming content organized as a set of segments;

determining a sample adaptive offset (SAO) filtering mode from at least three available SAO filtering modes in response to a calculated average quantization parameter per frame;

encoding the requested content utilizing the determined SAO filtering mode; and

causing a transmission of the encoded content.

6. The computer-implemented method of claim 5 wherein the at least three available SAO filtering modes includes at least five SAO filtering modes.

7. The computer-implemented method of claim 5 further comprising comparing the calculated average quantization parameter per frame to a threshold.

8. The computer-implemented method of claim 5 further comprising determining SAO filter parameters in response to the determined SAO filtering mode.

9. The computer-implemented method of claim 8 wherein the determined SAO filter parameters include offsets used in reconstruction of the encoded content.

10. The computer-implemented method of claim 5 further comprising selecting a first SAO filtering mode from the at least three available SAO filtering modes responsive to the calculated average quantization parameter per frame being less than a first threshold associated with the first SAO filtering mode.

11. The computer-implemented method of claim 5 further comprising determining the SAO filter type in response to the determined SAO filtering mode.

12. The computer-implemented method of claim 11 wherein the SAO filter type includes at least one of an Edge Offset (EO) type and a Band Offset (BO) type.

13. The computer-implemented method of claim 5 wherein one of the at least three available SAO filtering modes includes a block adaptive mode to preserve texture and sharpness of a reconstructed segment.

14. The computer-implemented method of claim 13 wherein encoding the requested content utilizing the block adaptive mode includes determining SAO filter parameters for an Edge Offset (EO) SAO filter type and a Band Offset (BO) SAO filter type.

15. The computer-implemented method of claim 14 wherein encoding the requested content utilizing the block adaptive mode further includes encoding the requested segment with EO SAO filter parameters associated with the EO SAO filter type to form a first encoded segment and encoding the requested segment with BO SAO filter parameters associated with the BO SAO filter type to form a second encoded segment.

16. The computer-implemented method of claim 15 wherein encoding the requested content utilizing the block adaptive mode further allows for reconstructing the first encoded segment and reconstructing the second encoded segment.

17. The computer-implemented method of claim 16 wherein encoding the requested content utilizing the block adaptive mode further includes selecting one of the EO SAO filter parameters, the BO SAO filter parameters, and no SAO filter parameters in response to a measure of sharpness of reconstructed segments.

19. The computer-implemented method of claim 16 further comprising determining filter offsets in response to the selected operational mode.

20. The computer-implemented method of claim 16 wherein the transmission includes the filter offsets.

18. A computer-implemented method to deliver content comprising:

receiving a request for encoded content segments;

selecting from a plurality of active sample adaptive offset filtering operational modes, wherein the selected operational mode is identified by average quantization parameter per frame information; and

causing a transmission of the encoded content segments.