[Libva] VAAPI encoding with Intel Sandybridge GPU

[Ratin]

Hi,

I am trying to use libva with Intel driver back-end for decode and
encode. Decoding works like charm, but when I try to encode, I get
some problems.
I got the same errors using the sample code provided by Intel for encoding ,

I get the error :

video: 720x480; fourcc:0x56595559
negotiated frame resolution: 640x480
libva: VA-API version 0.32.0
libva: va_getDriverName() returns 0
libva: Trying to open /usr/local/lib/dri/i965_drv_video.so
libva: va_openDriver() returns 0
encode frame:0
h264enc: i965_drv_video.c:1408: i965_EndPicture: Assertion
`obj_context->codec_state.encode.seq_param' failed.
Aborted


First frame's encoding does succeed, but any subsequent pictures does
not because  when end_frame is called,
obj_context->codec_state.encode.sq_param is NULL, but pic_param is
valid (reasonably so). But there is an assert in i965_EndPicture
function :


 if (obj_context->codec_type == CODEC_ENC) {
        assert(VAEntrypointEncSlice == obj_config->entrypoint);

        assert(obj_context->codec_state.encode.pic_param);
        assert(obj_context->codec_state.encode.seq_param);
        assert(obj_context->codec_state.encode.num_slice_params >= 1);
    } else ...

which traps the code. My question is why would the seq.param need to
be non-null for subsequent pictures?

Also the first frames H.264 bitstream does not look like regular h.264
bitstream that I am familiar with - usually  SPS / PPS 0x67, 0x68
followed by slice NALU 0x65 etc. But the bitstream looks like the
following (first uint is the offset) :

0000000 5300 0007 0000 0000 0000 0000 0000 0000
0000010 5040 5d16 7ff0 0000 0000 0000 0000 0000
0000020 0000 0000 0000 0000 0000 0000 0000 0000

0000040 93f8 a443 ecff 8770 ca3a 84bf fc7d b1e0
0000050 8c8c 5fc2 2481 8b8a 1f10 d558 a347 3638
0000060 6f06 2c98 a616 9988 6d46 271f 07a8 e866
0000070 16f2 a335 06b4 859c 738a 5bee 8cdf 6fd5
0000080 3c70 788a eda8 9462 6ce1 2768 cf16 d700


Any body have any idea?

Thanks

Ratin