System method and apparatus for seamlessly splicing data

• US 6,567,471 B1
• Filed: 03/25/1999
• Issued: 05/20/2003
• Est. Priority Date: 07/25/1997
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yoshinari, Hiromi
• Primary Examiner(s): Kelley, Chris
• Assistant Examiner(s): Bugg, George A
• Application Number:
  US09/275,999
• Time in Patent Office: 1,517 Days
• Field of Search: 375/240, 375/240.16, 375/240.26, 375/240.28, 348/409, 348/402
• US Class Current: 375/240.26
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• 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 19/114 Adapting the group of pictures [GOP] structure, e.g. number of B-frames between two anchor frames H04N19/107 takes precedence
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/142 Detection of scene cut or scene change
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• 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 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• 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 19/40 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 19/50 using predictive coding H04N19/61 takes precedence
• CPC Class Codes: H04N 19/513 Processing of motion vectors
• CPC Class Codes: H04N 19/52 by predictive encoding
• 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 21/23406 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 21/2343 : involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements video transcoding H04N19/40; media packet handling at the source H04L65/762
• 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 21/440254 : by altering signal-to-noise parameters, e.g. requantization
• CPC Class Codes: H04N 7/52 : Systems for transmission of a pulse code modulated video signal with one or more other pulse code modulated signals, e.g. an audio signal or a synchronizing signal assembling of a multiplex stream by combining a video stream with other content or additional data, remultiplexing of multiplex streams, insertion of stuffing bits into the multiplex stream, assembling of a packetised elementary stream at server side H04N21/236; disassembling of a multiplex stream, remultiplexing of multiplex streams, extraction or processing of Service Information, disassembling of packetised elementary stream at client side H04N21/434

Abstract

A plurality of bit streams are seamlessly spliced. Separate decoders decode each bit stream. A controller selects the decoded pictures according to a re-encoding range in the vicinity of a splicing point of the bit streams. Pictures presenting a reordering of the streams are excluded in the selection of the decoded pictures. An encoder re-encodes the pictures within the re-encoding range. When it is determined that crossover motion compensation exists between pictures of different streams, the controller changes the motion prediction direction of the problematic picture. The controller changes a motion prediction picture type of a picture which is improperly motion predicted with reference to another stream. A quantization characteristic or motion vectors for the new picture type are generated by the controller. The controller effects the encoding in accordance with a target amount of bits to prevent a breakdown of a buffer and a discontinuation of an amount of data occupancy thereof. A multiplexer multiplexes the original streams with the re-encoded stream to produce a seamless bit stream.

Claims

1. A splicing apparatus for splicing a plurality of source encoded streams, comprising:

splicing-point setting means for setting a splicing point for said plurality of source encoded streams;

decoding means for decoding pictures included in said plurality of source encoded streams in a region of said splicing point to generate decoded video data,

wherein a decoding-side decodes spliced streams and includes a video buffer verifier (VBV) characterized by a data occupancy;

re-encoding means for re-encoding said decoded video data to generate re-encoded streams;

spliced-stream producing means for switching between said source encoded streams and said re-encoded streams to produce said spliced streams; and

splice control means for controlling said re-encoding means and said spliced-stream producing means so as to prevent a discontinuity of said spliced streams when said spliced streams are decoded,

wherein said splice control means calculates a target amount of bits for re-encoding said decoded video data in re-encoding by said re-encoding means so as to prevent a discontinuity of a locus of said data occupancy of said VBV buffer at a switching point between said source encoded streams and said re-encoded streams or the splicing points of said re-encoded streams, and said re-encoding means encodes said decoded video data in accordance with said target amount of bits supplied from said splice control means.

2. A splicing apparatus for splicing a plurality of source encoded streams, comprising:

splicing-point setting means for setting a splicing point for said plurality of source encoded streams;

decoding means for decoding pictures included in said plurality of source encoded streams in a region of said splicing point to generate decoded video data,

wherein a decoding-side decodes spliced streams and includes a video buffer verifier (VBV) characterized by a data occupancy;

re-encoding means for re-encoding said decoded video data to generate re-encoded streams;

spliced-stream producing means for switching between said source encoded streams and said re-encoded streams to produce said spliced streams; and

splice control means for controlling said re-encoding means and said spliced-stream producing means so as to prevent a discontinuity of said spliced streams when said spliced streams are decoded,

wherein said splice control means controls said re-encoding means so as to approximate a locus of said data occupancy of said VBV buffer corresponding to said re-encoded streams to said locus of said data occupancy in said VBV buffer which is an original locus of said source encoded streams.

3. A splicing method for splicing a plurality of source encoded streams to produce spliced streams, comprising the steps of:

setting splicing points for said plurality of source encoded streams;

decoding pictures in a region of said splicing points of said plurality of source encoded streams and generating decoded video data,

wherein a decoding-side which decodes spliced streams and includes a video buffer verifier (VBV) characterized by a data occupancy;

re-encoding said decoded video data to generate re-encoded streams;

performing switching between said source encoded streams and said re-encoded streams to effect output so as to produce said spliced streams; and

controlling said re-encoding and said spliced streams producing so as to prevent a discontinuity of said spliced streams when said spliced streams are decoded,

wherein said splice control step calculates a target amount of bits for re-encoding said decoded video data in re-encoding which is performed in said re-encoding step so as to prevent a discontinuity of a locus of said data occupancy of said VBV buffer at a switching point between said source encoded streams and said re-encoded streams or the splicing point of said re-encoded streams, and said re-encoding step encodes said source encoded streams in accordance with said target amount of bits generated in said splice control step.

4. A splicing method for splicing a plurality of source encoded streams to produce spliced streams, comprising the steps of:

setting splicing points for said plurality of source encoded streams;

decoding pictures in a region of said splicing points of said plurality of source encoded streams and generating the decoded video data,

wherein a decoding-side which decodes spliced streams and includes a video buffer verifier (VBV) characterized by a data occupancy;

re-encoding said decoded video data to generate re-encoded streams;

performing switching between said source encoded streams and said re-encoded streams to effect output so as to produce said spliced streams; and

controlling said re-encoding step and said spliced streams producing step so as to prevent a discontinuity of said spliced streams when said spliced streams are decoded,

wherein said splice control step controls said re-encoding step so as to approximate a locus of said data occupancy of said VBV buffer corresponding to said re-encoded streams to said locus of said data occupancy of said VBV buffer which is an original locus of said source coded streams.

5. A splicing apparatus for splicing a plurality of source encoded streams, comprising:

a splicing-pointer for setting a splicing point for said plurality of source encoded streams;

a decoder for decoding pictures included in said plurality of source encoded streams in a region of said splicing point to generate decoded video data;

wherein a decoding-side decodes spliced streams and includes a video buffer verifier (VBV) characterized by a data occupancy;

a re-encoder for re-encoding said decoded video data to generate re-encoded streams;

a spliced-stream switcher for switching between said source encoded streams and said re-encoded streams to produce spliced streams; and

a splice controller for controlling said re-encoder and said spliced-stream switcher so as to prevent a discontinuity of said spliced streams when said spliced streams are decoded,

wherein said splice controller calculates a target amount of bits for re-encoding said decoded video data in re-encoding by said re-encoder so as to prevent a discontinuity of a locus of said data occupancy of said VBV buffer at a switching point between said source encoded streams and said re-encoded streams or said splicing points of said re-encoded streams, and said re-encoder re-encodes said decoded video data in accordance with said target amount of bits supplied from said splice controller.

6. A splicing apparatus for splicing a plurality of source encoded streams, comprising:

a splicing-pointer for setting a splicing point for said plurality of source encoded streams;

a decoder for decoding pictures included in said plurality of source encoded streams in a region of said splicing point to generate decoded video data;

wherein a decoding-side decodes spliced streams and includes a video buffer verifier (VBV) characterized by a data occupancy;

a re-encoder for re-encoding said decoded video data to generate re-encoded streams;

a spliced-stream switcher for switching between said source encoded streams and said re-encoded streams to produce spliced streams; and

a splice controller for controlling said re-encoder and said spliced-stream switcher so as to prevent a discontinuity of said spliced streams when said spliced streams are decoded,

wherein said splice controller controls said re-encoder so as to approximate a locus of said data occupancy of said VBV buffer corresponding to said re-encoded streams to said locus of said data occupancy in said VBV buffer which is an original locus of said source encoded streams.

7. Coding apparatus for coding source video data, comprising:

first encoding means for encoding said source video data to generate a first encoded stream;

decoding means for decoding said first encoded stream encoded by said first encoding means to generate decoded video data;

second encoding means for encoding said decoded video data to generate a re-encoded stream in accordance with a value of a coding parameter of said first encoded stream;

encoding control means for controlling said second encoding means with respect to said coding parameter so as to prevent overflow and underflow of a VBV buffer resulting from encoding said decoded video data,

wherein said encoding control means calculates a target amount of bits for re-encoding said decoded video data by said second encoding means so as to prevent a discontinuity of a locus of a data occupancy of said VBV buffer, and said second encoding means encodes said decoded video data in accordance with said target amount of bits supplied from said encoding control means.

8. A coding method for coding source video data, comprising the steps of:

encoding said source video data to output a first encoded stream;

decoding said first encoded stream encoded in a first encoding step to generate decoded video data;

encoding said decoded video data to generate a re-encoded stream in accordance with a value of a coding parameter of said first encoded stream;

controlling second-mentioned encoding step with respect to said coding parameter so as to prevent overflow and underflow of a VBV buffer resulting from encoding said decoded video data,

wherein said encoding control step calculates a target amount of bits for re-encoding said decoded video data in a second encoding step so as to prevent a discontinuity of a locus of a data occupancy of said VBV buffer, and said second encoding step encodes said decoded video data in accordance with said target amount of bits supplied from said encoding control step.

9. Coding apparatus for coding source video data,

wherein a decoding-side for decoding a spliced stream includes a video buffer verifier (VBV) comprising:

a first encoder for encoding said source video data to generate a first encoded stream;

a decoder for decoding said first encoded stream encoded by said first encoder to generate decoded video data;

a second encoder for encoding said decoded video data to generate a re-encoded stream in accordance with a value of a coding parameter of said first encoded stream;

an encoding controller for controlling said second encoder with respect to said coding parameter so as to prevent overflow and underflow of said VBV buffer resulting from encoding said decoded video data,

wherein said encoding controller calculates a target amount o f bits for re-encoding said decoded video data by said second encoder so as to prevent a discontinuity of a locus of a data occupancy of said VBV buffer, and said second encoder encode s said decoded video data in accordance with said target amount of bits supplied from said encoding controller.