Method for efficient processing of BTP enabled MPEG4 stream
A system is provided for providing a trickplay operation using a digital video recorder (DVR) when the video includes Broadcom Transport Packets (BTPs) designed for MPEG-2, but in an MPEG-4 video steam. In a first embodiment, to enable trickplay to function properly with MPEG-4 video, the BTP descriptors included with each group of data frames are disabled so that a single descriptor provided without BTPs that would otherwise be provided in MPEG-4 is all that remains. In a second embodiment, the 5 descriptors for MPEG-4 are combined into a single descriptor. In a third embodiment, the pace of decoding of the MPEG-4 descriptors is increased so that the speed of encoding all the 5 descriptors is comparable to the pace of decoding a single MPEG-2 descriptor.
1. A method for providing a trickplay operation using a digital video recorder (DVR) comprising:
receiving a request for a trickplay operation at the DVR;
obtain a plurality of descriptors for the requested trickplay operation from the DVR, wherein the plurality of descriptors include Broadcom Transport Packets (BTPs), wherein the plurality of descriptors further comprise:
a startcode descriptor;
a first BTP descriptor BTP0;
a Sequence Parameter Set (SPS)/Picture Parameter Set (PPS) descriptor:
a second BTP descriptor BTP1;
first frame data excluding a last transport stream (TS) packet for the associated frame data;
a third BTP descriptor BTP2; and
second frame data including the last TS packet for the transport stream;
prepare a single descriptor framework that combines the plurality of descriptors into a single combined descriptor;
read frame data from memory of the DVR in a single memory read operation;
combine the read frame data into the single combined descriptor; and
provide the single combined descriptor through a decoder for playback on a video player device.
2. The method of claim 1 , wherein the descriptors comprise a plurality of BTP descriptors and a Sequence Parameter Set (SPS)/Picture Parameter (PPS) descriptor.
3. The method of claim 1 , wherein the trickplay operations are provided for data encoded using the MPEG-4 standard.
4. The method of claim 1 , further comprising:
decoding using the decoder while altering decode processing speed so that descriptors are processed with a pace higher than remaining data, so that descriptors for each group of frame data are processed with a speed similar to a pace of processing a single MPEG-2 standard format descriptor.
5. An apparatus for providing trickplay operations for recorded video comprising:
a Digital Video Recorder (DVR) memory for storing video data;
a System on a Chip (SoC), comprising:
a processor that connects to the DVR for obtaining video data from the DVR memory;
a decoder for decoding video data obtained from the DVR memory and providing the decoded data for playback on a video player device; and
a memory for storing code that is executable by the processor to enable the SoC to perform the following steps:
receive a request for a trickplay operation at the DVR;
obtain a plurality of descriptors for the requested trickplay operation from the DVR, wherein the plurality of descriptors include Broadcom Transport Packets (BTPs), wherein the plurality of descriptors further comprise:
a startcode descriptor;
a first BTP descriptor BTP0;
a Sequence Parameter Set (SPS)/Picture Parameter Set (PPS) descriptor;
a second BTP descriptor BTP1;
first frame data excluding a last transport stream (TS) packet for the associated frame data;
a third BTP descriptor BTP2; and
second frame data including the last (TS) packet for the transport stream;
prepare a single descriptor framework that combines the plurality of descriptors into a single combined descriptor;
read frame data from memory of the DVR in a single memory read operation;
combine the read frame data into the single combined descriptor; and
provide the single combined descriptor through the decoder for playback on the video player device.
6. The apparatus of claim 5 , wherein the descriptors comprise a plurality of BTP descriptors and a Sequence Parameter Set (SPS)/Picture Parameter (PPS) descriptor.
7. The apparatus of claim 5 , wherein the trickplay operations are provided for data encoded using the MPEG-4 standard.
8. The apparatus of claim 5 , wherein the memory further stores code to cause the SoC to perform the following additional step:
decode using the decoder while altering decode processing speed so that descriptors are processed with a pace higher than remaining data, so that descriptors for each group of frame data are processed with a speed similar to a pace of processing a single MPEG-2 standard format descriptor.