METHOD AND APPARATUS FOR DISTRIBUTING VIDEO PROGRAM MATERIAL

• US 20100188581A1
• Filed: 01/27/2009
• Published: 07/29/2010
• Est. Priority Date: 01/27/2009
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: General Instrument Corporation (CommScope Holding Company, Inc.)
• Inventors: Wirick, Kevin S.
• Granted Patent: US 8,532,174 B2
• Time in Patent Office: Days
• US Class Current: 348/598
• CPC Class Codes: H04H 20/30 by a single channel
• CPC Class Codes: H04H 20/42 Arrangements for resource management
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

A method of distributing video program material includes encoding the program material in accordance with a first distribution constraint (CBR) to produce a first stream (A), encoding the program material in accordance with a second distribution constraint, which is more relaxed that the first distribution constraint, to produce a second stream (B), and employing the first and second streams to produce a third stream (C) representing differences between the first and second streams.

Claims

1. A method of distributing video program material, including:

encoding the program material in accordance with a first distribution constraint (CBR) to produce a first stream (A),

encoding the program material in accordance with a second distribution constraint, which is more relaxed that the first distribution constraint, to produce a second stream (B), and

employing the first and second streams to produce a third stream (C) representing differences between the first and second streams.

2. A method according to claim 1, wherein the first distribution constraint is that the first stream has a constant bit rate and the second distribution constraint is that the stream has a variable bit rate.

3. A method according to claim 1, including, before the steps of encoding the program material in accordance with the first and second distribution constraints, receiving a sequence of pictures, dividing each picture into blocks of chroma and luma values, and transforming the chroma and luma values to a set of frequency coefficients for each block, and wherein the step of employing the first and second streams to produce a third stream comprises subtracting a frequency coefficient of the first stream from a corresponding frequency coefficient of the second stream, whereby the third stream comprises, for each block, a succession of difference coefficients.

4. A method according to claim 3, further comprising entropy encoding both the first stream and the third stream, and creating a single program transport stream containing the first stream as a packetized elementary stream and containing the third stream as supplementary data.

5. A computer readable medium containing software that, when executed by a computer having an input for receiving video program material, performs a method including:

encoding the program material in accordance with a first distribution constraint (CBR) to produce a first stream (A),

encoding the program material in accordance with a second distribution constraint, which is more relaxed that the first distribution constraint, to produce a second stream (B), and

employing the first and second streams to produce a third stream (C) representing differences between the first and second streams.

6. Apparatus for distributing video program material, including:

a first encoder for encoding the program material in accordance with a first distribution constraint (CBR) to produce a first stream (A),

a second encoder for encoding the program material in accordance with a second distribution constraint, which is more relaxed that the first distribution constraint, to produce a second stream (B), and

a separator for employing the first and second streams to produce a third stream (C) representing differences between the first and second streams.

7. A method of processing a transport stream that contains a first stream representing frequency coefficients derived from blocks into which a sequence of pictures has been divided, the first stream having a constant bit rate, and also contains a supplemental data stream representing frequency coefficient adjustments derived from said blocks, the method comprising:

separating the first stream and the supplemental data stream from the transport stream,

entropy decoding the first stream and the supplemental data stream, and

combining the first stream and the supplemental data stream on a frequency coefficient basis to form a third stream representing adjusted frequency coefficients.

8. A method according to claim 7, wherein the supplemental data stream represents differences between the first stream and a variable bit rate stream representing said frequency coefficients.

9. A method according to claim 8, wherein the first and second streams are bit streams encoded in compliance with a first compression standard and the method comprises entropy encoding the third stream and decoding the third stream in accordance with a process for decoding a stream that has been encoded in compliance with the first compression standard.

10. A method according to claim 9, further comprising encoding the third stream in compliance with a second compression standard.

11. A computer readable medium containing software that, when executed by a computer having an input for receiving a transport stream that contains a first stream representing frequency coefficients derived from blocks into which a sequence of pictures has been divided, the first stream having a constant bit rate, and also contains a supplemental data stream representing frequency coefficient adjustments derived from said blocks, processes the transport stream by a method comprising:

separating the first stream and the supplemental data stream from the transport stream,

entropy decoding the first stream and the supplemental data stream, and

combining the first stream and the supplemental data stream on a frequency coefficient basis to form a stream representing adjusted frequency coefficients.

12. Apparatus for processing a transport stream that contains a first stream representing frequency coefficients derived from blocks into which a sequence of pictures has been divided, the first stream having a constant bit rate, and also contains a supplemental data stream representing frequency coefficient adjustments derived from said blocks, said apparatus comprising:

a transport demultiplexer for separating the first stream and the supplemental data stream from the transport stream,

entropy decoders for decoding the first stream and the supplemental data stream, and

a combiner for combining the first stream and the supplemental data stream on a frequency coefficient basis to form a third stream representing adjusted frequency coefficients.