Encoding apparatus and method, and multiplexing apparatus and method

• US 6,795,499 B1
• Filed: 05/31/2000
• Issued: 09/21/2004
• Est. Priority Date: 06/01/1999
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kato, Motoki, Takashima, Yoshikazu, Obata, Koji, Igi, Nobuhiro
• Primary Examiner(s): PHILIPPE, GIMS S
• Application Number:
  US09/583,422
• Time in Patent Office: 1,574 Days
• Field of Search: 375/240.01, 375/240.02, 375/240.16, 375/240.28, 386/52, 386/91, 386/111-112, 382/236, 348/419.1, 348/423.1, 348/500, 341/55
• US Class Current: 375/240.01
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/036 Insert-editing
• CPC Class Codes: H04N 19/115 Selection of the code volume for a coding unit prior to coding
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/172 the region being a picture, frame or field
• CPC Class Codes: H04N 19/177 the unit being a group of pictures [GOP]
• 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 19/197 including determination of the initial value of an encoding parameter H04N19/56 takes precedence
• 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 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/23406 involving management of server-side video buffer
• CPC Class Codes: H04N 21/23424 involving splicing one content stream with another content stream, e.g. for inserting or substituting an advertisement
• CPC Class Codes: H04N 21/23655 Statistical multiplexing, e.g. by controlling the encoder to alter its bitrate to optimize the bandwidth utilization
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/44016 involving splicing one content stream with another content stream, e.g. for substituting a video clip
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 9/8042 involving data reduction
• CPC Class Codes: H04N 9/8063 using time division multiplex of the PCM audio and PCM video signals

Abstract

An encoder to encode video streams representing a moving picture is provided whose video encoder calculates a bit storage quantity an STD video buffer should have when input of a stream ending with a first picture to the STD video buffer ends, calculates an initial bit storage quantity of a second picture of a stream concatenated to the end of the first picture and starting with the second picture, in a VBV buffer, based on the calculated bit storage quantity of the STD buffer, and encodes the stream based on the bit storage quantity. The video encoder further calculates a bit storage quantity of the STD video buffer, for decoding a picture of the stream in the STD video buffer, calculates, based on the calculated bit storage quantity, a bit storage quantity the VBV buffer should have for ending decoding of a fourth picture of a second stream concatenated to the beginning of a third picture and ending with the fourth picture, and encodes the stream based on the calculated bit storage quantity. With such encoding, a part of video streams can be re-coded without referencing to information indicative of an initial status of a video buffer when editing the video streams.

Claims

1. An encoder comprising:

means for re-encoding a first encoded stream ending with a first picture and a second stream concatenated to the end of the first picture and starting with a second picture;

a first means for calculating, for a video buffer in a virtual system target decoder model for decoding encoded streams re-encoded by the encoding means, a first bit storage quantity which should be when input of the first picture of the first encoded stream to the video buffer ends;

a second means for calculating, based on the first bit storage quantity calculated by the first bit storage quantity calculating means, a second bit storage quantity the video buffer in the virtual system target decoder model should have for starting decoding of the second picture of the second encoded stream according to the virtual system target model;

means for controlling, based on the second bit storage quantity calculated by the second bit storage quantity calculating means, re-encoding of the second encoded stream, effected by the encoding means; and

a multiplexing means for generating, based on the first bit storage quantity, a multiplexed stream including the second encoded stream re-encoded by the encoding controlling means.

2. An encoder comprising:

means for re-encoding a first encoded stream ending with a first picture and a second stream concatenated to the end of the first picture and starting with a second picture;

a first means for calculating, for a video buffer in a virtual system target decoder model for decoding encoded streams re-encoded by the encoding means, a first bit storage quantity which should be when input of the first picture of the first encoded stream to the video buffer ends;

a second means for calculating, based on the first bit storage quantity calculated by the first bit storage quantity calculating means, a second bit storage quantity the video buffer in the virtual system target decoder model should have for starting decoding of the second picture of the second encoded stream according to the virtual system target model;

means for controlling, based on the second bit storage quantity calculated by the second bit storage quantity calculating means, re-encoding of the second encoded stream, effected by the encoding means; and

means for changing a number of pictures included in the second encoded stream based on the second bit storage quantity;

the encoding means re-encoding the second encoded stream based on an instruction supplied from the number-of-pictures changing means.

3. An encoding method comprising steps of:

calculating, for a video buffer in a virtual system target decoder model for decoding re-encoded encoded streams, a first bit storage quantity which should be when input of a first picture of a first encoded stream ending with the first picture to the video buffer ends;

calculating, based on the first bit storage quantity, a second bit storage quantity the video buffer in the virtual system target decoder should have for starting, according to the virtual system target model, decoding of a second picture of a second encoded stream concatenated to the end of the first picture and beginning with the second picture;

re-encoding the second encoded stream based on the second bit storage quantity; and

generating, based on the first bit storage quantity, a multiplexed stream including the re-encoded second encoded stream.

4. An encoding method comprising steps of:

calculating, for a video buffer in a virtual system target decoder model for decoding re-encoded encoded streams, a first bit storage quantity which should be when input of a first picture of a first encoded stream ending with the first picture to the video buffer ends;

calculating, based on the first bit storage quantity, a second bit storage quantity the video buffer in the virtual system target decoder should have for starting, according to the virtual system target model, decoding of a second picture of a second encoded stream concatenated to the end of the first picture and beginning with the second picture;

re-encoding the second encoded stream based on the second bit storage quantity; and

changing a number of pictures included in the second encoded stream based on the second bit storage quantity to re-encode the second encoded stream whose number of pictures is changed.

5. An encoder comprising:

means for re-encoding a first encoded stream beginning with a first picture and a second stream concatenated to the beginning of the first picture and ending with a second picture;

means for calculating a first bit storage quantity a video buffer in a virtual system target decoder model for decoding encoded streams re-encoded by the encoding means should have for decoding the first picture of the first encoded stream;

means for calculating, based on the first bit storage quantity calculated by the first bit storage quantity calculating means, a second bit storage quantity the video buffer in the virtual system target decoder model should have for ending decoding of the second picture of the second encoded stream according to the virtual system target model;

means for controlling, based on the second bit storage quantity calculated by the second bit storage quantity calculating means, re-encoding of the second encoded stream, effected by the encoding means; and

means for changing a number of pictures included in the second encoded stream based on the second bit storage quantity;

the encoding means re-encoding the second encoded stream based on an instruction supplied from the number-of-pictures changing means.

6. An encoding method comprising steps of:

calculating a first bit storage quantity a video buffer in a virtual system target decoder model for decoding re-encoded encoded streams should have for decoding a first picture at the top of a first encoded stream;

calculating, based on the first bit storage quantity, a second bit storage quantity the video buffer should have for ending, according to the virtual system target model, decoding of a second picture of a second encoded stream concatenated to the beginning of the first picture and ending with the second picture;

re-encoding the second encoded stream based on the second bit storage quantity; and

changing a number of pictures included in the second encoded stream based on the second bit storage quantity to re-encode the second encoded stream whose number of pictures is changed.