This week was held in Incheon, South Korea, the 104th MPEG meeting. For this occasion, the GPAC team worked hard to prepare the following contribution.
This contribution discusses SVC, WebVTT and in particular the support for MPEG-HEVC (High Efficiency Video Coding, a.k.a. H.265) packaging, streaming and playback in GPAC. I’ve extracted the HEVC related part of this contribution in this post.
The playback support is powered by the open-source OpenHEVC decoder. HEVC support in GPAC should work on Windows and MacOSX (32 and 64 bits) starting with SVN revision 4524, and Linux and nightly builds should come soon. If you’re interested in that part, you can also read the post: Comparing HEVC and H.264 quality: see for yourself, by Iain Richardson.
Multiplexing HEVC bitstreams into ISOBMF
All profiles should be supported, interlace is not supported yet. The support is based on the study text of HEVC file format.
Command line example
|HEVC Import||MP4Box -add file.hvc -new file.mp4||Adds file.hvc (Annex B format) to the given file.The default import format uses “hvc1” storage.|
|MP4Box -add file.bin:FMT=HEVC -new file.mp4||FMT is used to indicate the format is HEVC, and can be omitted if the file extension is hvc, hevc or 265|
|MP4Box -add file.hvc:fps=50 -new file.mp4||FPS is by default 25, and should be specified most of the time as VUI timing is not yet parsed.|
|HEVC File inspection||MP4Box -info file.mp4MP4Box -info ID file.mp4||Gives info on the file or on the track.|
|HEVC Export||MP4Box –raw <trackId> file.mp4||Exports an HEVC file to annex B format.|
All DASH operations from GPAC (client and MP4Box) are supported on HEVC, including bitstream switching modes using hev1. For more information on DASH, see here.
MPEG-2 TS support
All MPEG-2 TS operations from GPAC (client and MP42TS) are supported on HEVC. MP42TS can be used to generate TS files usable for DASH or for injection in modulation chains; it can also be used to send the TS over an UDP or RTP stream in unicast or multicast mode.
Related links about GPAC and HEVC: