Systems, methods, and media for distributed transcoding video data
Methods, systems, and computer readable media for transcoding video data based on metadata are provided. In some embodiments, methods for transcoding video data using metadata are provided, the methods comprising: receiving a first plurality of encoded images from a storage device; decoding the first plurality of encoded images based on a first coding scheme to generate a plurality of decoded images; receiving a plurality of encoding parameters from the storage device; and encoding the plurality of decoded images into a second plurality of encoded images based on a second coding scheme and the plurality of encoding parameters.
1. A method for transcoding video data into a set of multiple alternate video streams, the method comprising:
providing at least a portion of encoded video, in a first format that includes a first plurality of encoded images, to a plurality of encoding processors;
providing media metadata for the portion of encoded video to the plurality of encoding processors, wherein the media metadata comprises coding parameters and scene information for a set of video scenes of the portion of the encoded video; and
encoding, at each of the plurality of encoding processors, the portion of the encoded video into a transcoded portion of encoded video of an alternate video stream in a second format, wherein:
encoding the portion of the encoded video comprises determining a number of bits to encode a group of pictures (GOP) in the portion based at least in part on a number of frames between the start and end of the GOP as indicated by the media metadata,
the GOP comprises a plurality of consecutive scenes, the length of the GOP equals the number of frames between at least two adjacent scene changes in the plurality of consecutive scenes,
the start of the GOP corresponds to the start of the first scene of the plurality of consecutive scenes, and
the end of the GOP corresponds to the end of the last scene of the plurality of consecutive scenes.
2. The method of claim 1 , wherein encoding the portion of the encoded video comprises generating an I-frame as a first frame of the GOP using the scene information.
3. The method of claim 1 , wherein encoding the portion of the encoded video comprises generating a set of one or more prediction images based on the scene information.
4. The method of claim 1 , wherein encoding the portion of the encoded video further comprises:
determining a structure of the GOP based on the media metadata; and
determining a set of quantization parameters (QP) for the GOP based on the determined structure of the GOP.
5. The method of claim 1 , wherein the scene information includes a set of scene change types for transitions between scenes of the portion of encoded video and encoding the portion of the encoded video is further based on the set of scene change types.
6. The method of claim 1 , wherein the scene information for a scene comprises at least one of the group consisting of scene start, scene end, and a measure of a length of the scene.
7. The method of claim 1 , wherein the scene information comprises at least one selected from the group consisting of scene complexity information and a video scene type.
8. The method of claim 1 , wherein the scene information comprises a scene change indication signal.
9. The method of claim 1 , wherein encoding the portion of the encoded video is performed in parallel across the plurality of encoding processors.
10. A transcoding system comprising:
a set of one or more processors; and
a non-volatile storage containing an application for causing the set of one or more processors to perform the steps of:
providing at least a portion of encoded video, in a first format that includes a first plurality of encoded images, to a plurality of encoding processors;
providing media metadata for the portion of encoded video to the plurality of encoding processors, wherein the media metadata comprises coding parameters and scene information for a set of video scenes of the portion of the encoded video; and
encoding, at each of the plurality of encoding processors, the portion of the encoded video into a transcoded portion of encoded video of an alternate video stream in a second format, wherein:
encoding the portion of the encoded video comprises determining a number of bits to encode a group of pictures (GOP) in the portion based at least in part on a number of frames between the start and end of the GOP as indicated by the media metadata,
the GOP comprises a plurality of consecutive scenes,
the length of the GOP equals the number of frames between at least two adjacent scene changes in the plurality of consecutive scenes;
the start of the GOP corresponds to the start of the first scene of the plurality of consecutive scenes, and
the end of the GOP corresponds to the end of the last scene of the plurality of consecutive scenes.
11. The transcoding system of claim 10 , wherein encoding the portion of the encoded video comprises generating an I-frame as a first frame of the GOP using the scene information.
12. The transcoding system of claim 10 , wherein encoding the portion of the encoded video comprises generating a set of one or more prediction images based on the scene information.
13. The transcoding system of claim 10 , wherein encoding the portion of the encoded video further comprises:
determining a structure of the GOP based on the media metadata; and
determining a set of quantization parameters (QP) for the GOP based on the determined structure of the GOP.
14. The transcoding system of claim 10 , wherein the scene information includes a set of scene change types for transitions between scenes of the portion of encoded video and encoding the portion of the encoded video is further based on the set of scene change types.
15. The transcoding system of claim 10 , wherein the scene information for a scene comprises at least one of the group consisting of scene start, scene end, and a measure of a length of the scene.
16. The transcoding system of claim 10 , wherein the scene information comprises at least one selected from the group consisting of scene complexity information and a video scene type.
17. The transcoding system of claim 10 , wherein the scene information comprises a scene change indication signal.
18. The transcoding system of claim 10 , wherein encoding the portion of the encoded video is performed in parallel across the plurality of encoding processors.
19. The method of claim 1 , wherein the transcoded portion includes a second plurality of encoded images that are encoded based on the coding parameters and the scene information for the set of video scenes.
20. The transcoding system of claim 10 , wherein the transcoded portion includes a second plurality of encoded images that are encoded based on the coding parameters and the scene information for the set of video scenes.