Enhanced block-request streaming using cooperative parallel HTTP and forward error correction
A block-request streaming system provides for improvements in the user experience and bandwidth efficiency of such systems, typically using an ingestion system that generates data in a form to be served by a conventional file server (HTTP, FTP, or the like), wherein the ingestion system intakes content and prepares it as files or data elements to be served by the file server, which might or might not include a cache. A client device can be adapted to take advantage of the ingestion process as well as including improvements that make for a better presentation independent of the ingestion process. In the block-request streaming system, the an ingestion system generates data according to erasure codes and the client device, through various selection and timing of requests for media data and redundant data, can efficiently decode media to provide for presentations.
1. A computer-implemented method, comprising:
determining, at a client device, media blocks that are needed for a media presentation;
identifying one or more forward error correction (FEC) files, the one or more FEC files including one or more FEC blocks usable by the client device to recover portions of the media blocks not received by the client device;
determining a position of the one or more FEC blocks within the one or more FEC files;
transmitting a first request for a first media file that is usable by the client device to provide the media presentation;
receiving the first media file;
transmitting a second request for a second media file that is usable by the client device to provide additional portions of the media presentation;
receiving the second media file prior to completion of receiving the first media file;
transmitting a third request for an FEC file that is usable by the client device to recover portions of either the first media file or the second media file not yet received by the client device; and
receiving at least a portion of the FEC file prior to completion of receiving the first media file and the second media file.
2. The method of claim 1 , further comprising:
sending requests for media files in parallel, the media files including the media blocks;
receiving the media files in response to requests; and
managing requests in parallel, wherein managing includes sending requests while pending requests are outstanding and initiating receiving of responses to such requests prior to completion of prior responses.
3. The method of claim 1 , wherein a media presentation is requested as a plurality of media files including the media blocks.
4. The method of claim 1 , further comprising recovering portions of media files not yet received using FEC symbols from the FEC file.
5. The method of claim 1 , further comprising:
determining a bandwidth allocation among a plurality of requests;
determining playout times associated with the plurality of requests; and
adjusting the bandwidth allocation among the plurality of requests to reduce a probability of a stall, wherein a stall occurs when a playout time is reached before media that is associated with that playout time is available for playout.
6. The method of claim 1 , wherein a plurality of requests for media files comprises a plurality of requests for byte ranges from one or more files.
7. The method of claim 1 , further comprising determining an amount of data of a plurality of media files to request based on a capacity and contents of a media buffer.
8. The method of claim 1 , further comprising:
determining which of a plurality of outstanding requests to cancel based on a network condition; and
sending cancellation requests to cancel determined requests.
9. The method of claim 1 , further comprising determining which FEC blocks to request based on a target repair data ratio, a symbol size, a byte offset of a prior media fragment and a byte offset of a current media fragment.
10. An apparatus, comprising:
a processor configured to:
determine media blocks that are needed for a media presentation;
identify one or more forward error correction (FEC) files, the one or more FEC files including one or more FEC blocks usable by the apparatus to recover portions of the media blocks not received by the apparatus; and
determine a position of the one or more FEC blocks within the one or more FEC files
a transmitter configured to transmit a first request for a first media file that is usable to provide the media presentation; and
a receiver configured to receive the first media file;
wherein the transmitter is further configured to transmit a second request for a second media file that is usable to provide additional portions of the media presentation;
wherein the receiver is further configured to receive the second media file prior to completion of receiving the first media file;
wherein the transmitter is further configured to transmit a third request for an FEC file that is usable to recover portions of either the first media file or the second media file not yet received; and
wherein the receiver is further configured to receive at least a portion of the FEC file prior to completion of receiving the first media file and the second media file.
11. The apparatus of claim 10 , wherein the processor is further configured to:
send requests for media files in parallel, the media files including the media blocks;
receive the media files in response to requests; and
manage requests in parallel, wherein managing includes sending requests while pending requests are outstanding and initiating receiving of responses to such requests prior to completion of prior responses.
12. The apparatus of claim 10 , wherein a media presentation is requested as a plurality of media files including the media blocks.
13. The apparatus of claim 10 , wherein the processor is further configured to recover portions of media files not yet received using FEC symbols from the FEC file.
14. The apparatus of claim 10 , wherein the processor is further configured to:
determine a bandwidth allocation among a plurality of requests;
determine playout times associated with the plurality of requests; and
adjust the bandwidth allocation among the plurality of requests to reduce a probability of a stall, wherein a stall occurs when a playout time is reached before media that is associated with that playout time is available for playout.
15. The apparatus of claim 10 , wherein a plurality of requests for media files comprises a plurality of requests for byte ranges from one or more files.
16. The apparatus of claim 10 , wherein the processor is further configured to determine an amount of data of a plurality of media files to request based on a capacity and contents of a media buffer.
17. The apparatus of claim 10 , wherein the processor is further configured to:
determine which of a plurality of outstanding requests to cancel based on a network condition; and
send cancellation requests to cancel determined requests.
18. The apparatus of claim 10 , wherein the processor is further configured to determine which FEC blocks to request based on a target repair data ratio, a symbol size, a byte offset of a prior media fragment and a byte offset of a current media fragment.
19. One or more non-transitory computer-readable media storing computer-executable instructions that, when executed, cause one or more computing devices to:
determine media blocks that are needed for a media presentation;
identify one or more forward error correction (FEC) files, the one or more FEC files including one or more FEC blocks usable by a client device to recover portions of the media blocks not received by the client device;
determine a position of the one or more FEC blocks within the one or more FEC files;
determine one or more FEC files that contain the one or more FEC blocks;
transmit a first request for a first media file that is usable to provide the media presentation;
receive the first media file;
transmit a second request for a second media file that is usable to provide additional portions of the media presentation;
receive the second media file prior to completion of receiving the first media file;
transmit a third request for an FEC file that is usable to recover portions of either the first media file or the second media file not yet received; and
receive at least a portion of the FEC file prior to completion of receiving the first media file and the second media file.
20. The one or more non-transitory computer-readable media of claim 19 , further storing computer-executable instructions that, when executed, cause the one or more computing devices to:
send requests for media files in parallel;
receive the media files in response to requests; and
manage requests in parallel, wherein managing includes sending requests while pending requests are outstanding and initiating receiving of responses to such requests prior to completion of prior responses.
21. The one or more non-transitory computer-readable media of claim 19 , wherein a media presentation is requested as a plurality of media files.
22. The one or more non-transitory computer-readable media of claim 19 , further storing computer-executable instructions that, when executed, cause the one or more computing devices to recover portions of media files not yet received using FEC symbols from the FEC file.
23. The one or more non-transitory computer-readable media of claim 19 , further storing computer-executable instructions that, when executed, cause the one or more computing devices to:
determine a bandwidth allocation among a plurality of requests;
determine playout times associated with the plurality of requests; and
adjust the bandwidth allocation among the plurality of requests to reduce a probability of a stall, wherein a stall occurs when a playout time is reached before media that is associated with that playout time is available for playout.
24. The one or more non-transitory computer-readable media of claim 19 , wherein a plurality of requests for media files comprises a plurality of requests for byte ranges from one or more files.
25. The one or more non-transitory computer-readable media of claim 19 , further storing computer-executable instructions that, when executed, cause the one or more computing devices to determine an amount of data of a plurality of media files to request based on a capacity and contents of a media buffer.
26. The one or more non-transitory computer-readable media of claim 19 , further storing computer-executable instructions that, when executed, cause the one or more computing devices to:
determine which of a plurality of outstanding requests to cancel based on a network condition; and
send cancellation requests to cancel determined requests.
27. The one or more non-transitory computer-readable media of claim 19 , further storing computer-executable instructions that, when executed, cause the one or more computing devices to determine which FEC blocks to request based on a target repair data ratio, a symbol size, a byte offset of a prior media fragment and a byte offset of a current media fragment.