Performing personal video recording (PVR) functions on digital video streams

• US 8,923,688 B2
• Filed: 12/11/2002
• Issued: 12/30/2014
• Est. Priority Date: 09/12/2001
• Status: Active Grant

• Current Assignee: Broadcom Corporation (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Aggarwal, Gaurav, Rao, Arun Gopalakrishna, Kellerman, Marcus, Erickson, David, Demas, Jason, Bhatia, Sandeep, Hulmani, Girish
• Primary Examiner(s): NGUYEN BA, HOANG VU A
• Application Number:
  US10/318,295
• Publication Number:
  US 20030169815A1
• Time in Patent Office: 4,402 Days
• Field of Search: 375/240.12, 375/240.05, 375/240.07, 386/347, 386/348, 386/345, 386/356
• US Class Current: 386/347
• CPC Class Codes: G06T 9/004 Predictors, e.g. intraframe, interframe coding
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/50 using predictive coding H04N19/61 takes precedence
• CPC Class Codes: H04N 19/52 by predictive encoding
• CPC Class Codes: H04N 19/573 Motion compensation with multiple frame prediction using two or more reference frames in a given prediction direction
• CPC Class Codes: H04N 19/577 Motion compensation with bidirectional frame interpolation, i.e. using B-pictures
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/2387 Stream processing in response to a playback request from an end-user, e.g. for trick-play
• CPC Class Codes: H04N 21/4147 PVR [Personal Video Recorder] H04N5/76 takes precedence ; arrangements for broadcast with accumulation-type receivers H04H20/40
• CPC Class Codes: H04N 21/4331 Caching operations, e.g. of an advertisement for later insertion during playback
• CPC Class Codes: H04N 21/4385 Multiplex stream processing, e.g. multiplex stream decrypting
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream

Abstract

Presented herein are systems, methods, and apparatus for improving performance of video decoders during rewind and fast forward operation. Video decoder performance is improved by avoiding repetitive decoding of prediction pictures. When a decoded prediction picture is stored in a frame buffer, techniques are presented for decoding multiple pictures in the rewind order which are dependent thereon, displaying the picture directly from the frame buffer, and setting one type of prediction picture as another type of prediction picture.

Claims

1. A method for decoding pictures, said method comprising:

selecting a group of pictures in a rewind order, the group of pictures comprising a plurality of pictures;

decoding a reference picture of the plurality of pictures;

storing the decoded reference picture in a reference picture buffer, the reference picture buffer comprising a memory;

displaying each additional picture of the plurality of pictures in the rewind order, the each additional picture being data dependent on the reference picture, the displaying of the each additional picture comprising;

decoding each P-picture between the reference picture and the each additional picture to be displayed; and

decoding the each additional picture based on the decoded reference picture stored in the reference picture buffer and the each decoded P-picture between the reference picture and the each additional picture to be displayed;

determining that a next picture to be displayed is the reference picture; and

displaying the reference picture directly from the reference picture buffer based on the determination that the next picture to be displayed is the reference picture.

2. The method of claim 1, wherein the reference picture is stored during displaying the each additional picture of the plurality of pictures.

3. An integrated circuit comprising:

memory for storing a plurality of instructions;

a processor connected to the memory;

wherein execution of the plurality of instructions by the processor causes;

selecting a group of pictures in a rewind order, the group of pictures comprising a plurality of pictures;

decoding a reference picture of the plurality of pictures;

storing the decoded reference picture in a reference picture buffer;

displaying each additional picture of the plurality of pictures in the rewind order, the each additional picture being data dependent on the reference picture, the displaying of the each additional picture comprising;

decoding each P-picture between the reference picture and the each additional picture to be displayed; and

decoding the each additional picture based on the decoded reference picture stored in the reference picture buffer and the each decoded P-picture between the reference picture and the each additional picture to be displayed;

determining that a next picture to be displayed is the reference picture; and

displaying the reference picture directly from the reference picture buffer based on the determination that the next picture to be displayed is the reference picture.

4. The integrated circuit of claim 3, wherein the reference picture comprises an intra-coded picture.

5. The integrated circuit of claim 3, wherein the reference picture is stored during displaying the each additional picture of the plurality of pictures.

6. A method for decoding pictures, the method comprising:

selecting a group of pictures in a fast forward order, the group of pictures comprising a plurality of pictures;

decoding a prediction picture of the plurality of pictures;

storing the decoded prediction picture in a frame buffer, the frame buffer comprising a memory;

displaying a next picture for display of the plurality of pictures in the fast forward order, the next picture for display being data dependent on the prediction picture, the displaying of the next picture for display comprising;

decoding each P-picture between the prediction picture and the next picture for display; and

decoding the next picture for display based on the decoded prediction picture stored in the frame buffer and the each decoded P-picture between the prediction picture and the next picture for display;

determining that a second next picture for display is the prediction picture; and

displaying the prediction picture directly from the frame buffer based on the determination that the second next picture for display is the prediction picture.

7. The method of claim 6, wherein the prediction picture comprises a past prediction picture.

8. The method of claim 6, wherein the prediction picture comprises a future prediction picture.

9. A video decoder for displaying pictures, said video decoder comprising:

a first frame buffer for storing a prediction picture;

a second frame buffer for storing a picture to be displayed;

a display engine for displaying the picture to be displayed; and

a decompression engine configured to;

select a group of pictures in a fast forward order, the group of pictures comprising a plurality of pictures;

decode a prediction picture of the plurality of pictures;

store the decoded prediction picture in the first frame buffer;

cause the display engine to display a next picture for display of the plurality of pictures in the fast forward order from the second frame buffer, the next picture for display being data dependent on the prediction picture, the display of the next picture for display comprising;

decode each P-picture between the prediction picture and the next picture for display; and

decode the next picture for display based on the decoded prediction picture stored in the first buffer and the each decoded P-picture between the prediction picture and the next picture for display;

determine that a second next picture for display is the prediction picture; and

cause the display engine to display the prediction picture directly from the first frame buffer based on the determination that the second next second picture for display is the prediction picture.

10. The video decoder of claim 9, wherein the prediction picture comprises a past prediction picture.

11. The video decoder of claim 9, wherein the prediction picture comprises a future prediction picture.

12. The video decoder of claim 9, wherein the prediction picture comprises an intra-coded picture.

13. The video decoder of claim 12, wherein the prediction picture comprises a P-picture with at least one intra-coded slice.