RFC: Static libva builds with embedded drivers

[tmm1]

Hi, I've been using the following patch along with CFLAGS="-DSTATIC_DRIVER" to build libva statically (combined with a static build of the intel-driver) and link it together with a static build of ffmpeg: https://github.com/01org/libva/compare/6b8fbf6ea348bb2970af2df9b8e0b3493e3e86f5...ad5f1f4b3491ccef390074f791cf36f4ec39b065

Is there any interest in including something like this in libva, perhaps with ./configure --enable-static? If so, I'm happy to submit a PR to do so.

At the moment, my patch hacks in an extern VADriverInit __vaDriverInit_0_XX and expects the embedded driver to expose that symbol. This means only a single driver can be embedded. Perhaps it makes sense to generalize this approach further to allow multiple drivers to all be linked statically together along with a static libva.

[fhvwy]

No comment on the code, but if you want to do this then please be very careful about licensing because the combined work will be covered by more than the MIT licence of libva. In particular, the Intel driver contains proprietary blobs without source code, and is therefore incompatible with many licences. For example, an ffmpeg linked with a combined libva+intel driver and libx264 would not be distributable, and that really should be detectable at ffmpeg configure time to avoid accidental GPL violations.

[tmm1]

Thanks for the heads up about licensing.

The intel-vaapi-driver has an MIT license here: https://github.com/01org/intel-vaapi-driver/blob/master/COPYING

Can you point me at the proprietary blobs present in that driver? I'm having a hard time finding them.

[fhvwy]

The MIT licence indeed applies to the source code which is available, but it says nothing about that source code being complete.

See code like https://github.com/01org/intel-vaapi-driver/blob/master/src/i965_avc_encoder_kernels.c, which is compiled from some other source and included as a binary embedded in a source file. Technically this generated source file is copyable/editable under MIT terms, but it definitely wouldn't count as the full "Corresponding Source" required by the GPL.

(intel/intel-vaapi-driver#220 has a more complete list of files without source code.)

[xhaihao]

Thanks, but we haven't a plan to support static libva build