GPAC has never been so alive!
We are happy to announce a new release of GPAC (v0.8.0), featuring AV1, HDR, full CENC, CMAF, HEIF and ATSC3.0 support! For more details, check the detailed changelog.
Enjoy, and stay tuned for more info on GPAC !
GPAC has never been so alive!
We are happy to announce a new release of GPAC (v0.8.0), featuring AV1, HDR, full CENC, CMAF, HEIF and ATSC3.0 support! For more details, check the detailed changelog.
Enjoy, and stay tuned for more info on GPAC !
Dear reader,
GPAC has added support for new codecs recently:
This article gives you some useful command lines to use AV1 streams, but the same can be applied for VP9 streams.
Command-line for importing AV1 streams into MP4 files
To store an AV1 bitstream into an ISOBMFF/MP4 file , use the following command line. If the input file is called *.av1, its content can be OBUs (as specified in Section 5 of the AV1 specification), IVF or Annex B bitstreams. WebM streams are not supported. You can also call OBU-based bistream *.obu and IVF files *.ivf:
MP4Box -add file.av1 file_av1.mp4
If your file extension is not recognized by MP4Box, you can indicate the bitstream format with “:fmt=obu” or :fmt=AnnexB or fmt=IVF (case insensitive) as follows:
MP4Box -add file.xxx:fmt=obu file_av1.mp4
AV1 bitstreams may not contain frame rate information, you can use the following to indicate it:
MP4Box -add file.av1:fps=1000 file_av1.mp4
Command-line for AV1 adaptive streaming preparation
You can use the usual MP4Box command line parameters to segment your AV1 MP4 file and prepare it for adaptive streaming. The following command line will generate an MPEG-DASH onDemand manifest based on an AV1 representation (with its ‘codecs’ parameter) and it will create a segmented MP4 file with segments starting at AV1 KEY FRAMEs and targeting 1 second duration.
MP4Box -dash 1000 -profile onDemand file_av1.mp4
Command-line for AV1 encryption/decryption
Encryption of AV1 streams in MP4 files follows the general principles given by MPEG’s Common Encryption specification. To use MP4Box for encryption or decryption, use the following command lines where the file ‘info.xml’ is an XML file that provides encryption parameters, as described in more details here. Example of such XML files can be found in our test base.
Encryption:
MP4Box -crypt info.xml -out file_av1_encrypted.mp4 file_av1.mp4
Decryption:
MP4Box -decrypt info.xml -out file_av1_decrypted.mp4 file_av1_encrypted.mp4
Acknowledgements and conclusion
The work on AV1 and VP9 was largely sponsored by Alliance for Open Media and Netflix. Kudos to them 🙂
As usual, if you find any bug or miss documentation, let us know.
It’s demo season !
GPAC is powering a 16K 360° video demo at Roland Garros 2017 as part of the Live360TV project:
We are also exhibiting at the Future en Seine event as part of the 4Ever-2 project, where we demonstrate hybrid scalable broadcast broadband with an AVC 1080p 50hz SDR base broadcast enhanced with an SHVC UHD HDR (PQ) layer carried over broadband DASH, check it out !
SHVC decoding is powered by our close friends at openHEVC, broadband/broadcast synchronization is achieved through MPEG-2 TS TEMI.
The H2B2VS project has received the excellence award in multimedia for its outstanding work, at the Celtic-Plus Event in Barcelona on 18 May 2017!
During this project, the GPAC team has standardized the MPEG-2 TEMI extensions used for broadcast-brodband synchronization and implemented several demos based on this techno (small tutorial here on how to use GPAC for such demonstrations).
A new release of GPAC is out (0.7.0), check it out ! New features, many fixes and improvements, see the changelog.
Also note that you can meet us at NAB in Las Vegas in two weeks and at EBU Broadcast Thinking. The focus is on low latency MPEG-DASH. Don’t hesitate to contact us!