Transcoding mpeg bittstreams for adding sub-picture content

• US 20050018770A1
• Filed: 12/14/2002
• Published: 01/27/2005
• Est. Priority Date: 12/28/2001
• Status: Active Grant

• Current Assignee: Magnolia Licensing LLC (IP Edge LLC)
• Original Assignee: Thomson Licensing SA (Vantiva SA)
• Inventors: Ostermann, Ralf, Adolph, Dirk
• Granted Patent: US 8,902,314 B2
• Time in Patent Office: Days
• US Class Current: 375/240.160
• 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 19/467 characterised by the embedded information being invisible, e.g. watermarking
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

A DVD transport stream including a video and a sub-picture stream shall be transcoded to a broadcasting transport stream. For this a decoding-encoding-chain merging video and sub-picture into a single video bitstream to conserve the information of the sub-pictures although not in the broadcasting format reserved is provided. By performing a sub-picture macroblock analysis the transcoding can be controlled such that the motion estimation unit of a standard MPEG-2 encoder and/or the entire decoding loop within the encoder can be saved.

Claims

1. Method for merging encoded video picture data from a transport stream including a video bitstream and a sub-picture bitstream, comprising, digitally decoding said sub-picture bitstream, extracting position information for the video picture area that will be affected by the sub-picture, generating a merged bitstream consisting of unaltered encoded video data from the video bitstream in the area that remains unaffected by the sub-picture and newly encoded video data for the area where the sub-picture affects the video content in the picture.

2. Method according to claim 1, wherein said digitally encoding includes standard MPEG-2 encoding with motion estimation and prediction.

3. Method according to claim 1, wherein said position information defines a frame area, preferably consisting of macroblocks, which is affected by the sub-picture.

4. Method according to claim 1, wherein said digitally encoding includes motion compensation being limited to a zero vector motion compensation.

5. Method according to claim 1, wherein video picture data are processed as macroblocks and all macroblocks in the affected picture area are intra encoded.

6. Method according to claim 1, wherein the merged bitstream is a MPEG2 transport stream and the transport packets are delivered in bus packets over a bus connection of a home network to a device being equipped with MPEG2 decoder.

7. Method according to claim 6, wherein the bus of the home network is the IEEE1394 bus.

8. Device for merging encoded video picture data from a transport stream including an encoded video bitstream and an encoded sub-picture bitstream, comprising, decoding means for digitally decoding said video and sub-picture bitstream, adding means for merging decoded video and sub-picture data and encoding means for digitally encoding said merged video and sub-picture data to generate a new video bitstream.

9. Device according to claim 8, wherein said encoding means includes a standard MPEG-2 encoder.

10. Device according to claim 8, wherein said device includes determining means for processing at least said decoded subpicture data to extract position information for the video picture area that will be affected by the sub-picture, preferably in units of macroblocks.

11. Device according to claim 10, wherein said position information controls switching means for copying the encoded macroblocks from the video bitstream that are unaffected by the sub-picture to the output and for forwarding the encoded merged video and sub-picture data to the output to form a new video bitstream.

12. Device according to claim 8, wherein said encoding means includes motion compensation means exclusively compensating with a zero motion vector.

13. Device according to claim 8, wherein picture data are processed as macroblocks and all macroblocks are intra encoded by said encoding means.

14. Device according to claim 8, wherein the merged bitstream is a MPEG2 transport stream and the device comprises means for sorting the MPEG2 transport packets in bus packets for a bus connection of a home network.

15. Device according to claim 14, wherein the means for sorting the MPEG2 transport packets in bus packets are included in a IEEE1394 bus interface.