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MPEG-DASH SRD and HEVC tiling for VR videos

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We were at MMSys 2016 talking about new nice features in GPAC: support for MPEG-DASH Spatial Relation Description and HEVC motion-constrained tiling!
We had a quick poster presenting our two demos
Continue reading MPEG-DASH SRD and HEVC tiling for VR videos

Open positions in our lab

The GPAC team at Telecom ParisTech has two new open positions:

We also have an open PhD position on peer-to-peer streaming in web browsers, description available here.

If you would like to join us in our offices in Paris and participate in our open-source and R&D activities, don’t hesitate to contact us!



As part of the 4Ever project, we have been releasing an HEVC and DASH ultra high definition dataset, ranging from 8bit 720p 30Hz up to 10bit 2160p 60 Hz. The dataset is released under CC BY-NC-ND.
The data set web page is here, and more information on the dataset can also be found in this article.

GPAC goes 10 bit

⚠ The content of this page may be outdated.
Please refer to this page for more up to date information:


We have introduced support for 10 bit HEVC profile last week in GPAC, using the great openHEVC decoder. Doing so, we also introduced support for 10 bit display. The support requires a graphics card capable of driving a 10 bit display; this support is usually enabled via the control application of your GPU. Do not worry, 10-bit video will still show in 8 bit if your graphics card doesn’t handle 10 bit output !

The setup currently requires manual configuration of the player. Edit the GPAC configuration file and set the following keys:




You can also enable it from the command line:

MP4Client -opt Compositor:OpenGLMode=always -opt Video:GLNbBitsPerComponent=10 -opt Systems:Output8bit=no

This has only been successfully tested on windows, using the “DirectX Video Output” module of GPAC. It has been tested on a ATI FirePro W5000 GPU but should work the same on other ATI models or NVidia ones.
Support for 10 bit is also enabled on X11 (same config) but doesn’t seem to work with the FirePro W5000.

We welcome any feedback you may give on the compatibility of GPAC’s 10bit support on any GPUs !


HEVC Live Showcase

As part of the 4Ever project, GPAC is currently on-air at Roland Garros, the French Tennis Open, for a world premiere live broadcast of 720p50 HEVC over DVB-T2 (broadcasted in Rennes through ImaginLab), IPTV and MPEG-DASH ! If you’re in town and want to check it out, drop us a line or stop at the RGLab booth !

GPAC 0.5.0

Release 0.5.0 of GPAC is finally out, with many new features and bug fixes, including:
– MPEG-DASH and HLS support (players and MP4Box)
– MPEG-U Widgets and UPnP support in the player
– Stereo and multiview display support
– Better AVC and SVC support including OpenSVC decoder integration
– More live tools: RTP, MPEG-TS, T-DMB support, scene encoders (BIFS and RME/DIMS)
– iOS and Android support
– and many other good things

Find out more at

Enjoy and spread the news!


We have a few R&D positions opening this spring (home networking, hybrid broadcast/brodband delivery, next-generation TV services…), so feel free to contact us if you are interested (M.Sc. or equivalent, PhD candidates welcome).