[FFmpeg-devel] [PATCH, v2] lavc/vaapi_encode: grow packet if vaMapBuffer returns multiple buffers

[Fu, Linjie]

> -----Original Message-----
> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> Of Fu, Linjie
> Sent: Tuesday, June 4, 2019 17:11
> To: ffmpeg-devel at ffmpeg.org
> Cc: Mark Thompson <sw at jkqxz.net>
> Subject: Re: [FFmpeg-devel] [PATCH, v2] lavc/vaapi_encode: grow packet if
> vaMapBuffer returns multiple buffers
> 
> > -----Original Message-----
> > From: Fu, Linjie
> > Sent: Friday, May 31, 2019 08:35
> > To: ffmpeg-devel at ffmpeg.org
> > Cc: Fu, Linjie <linjie.fu at intel.com>
> > Subject: [PATCH,v2] lavc/vaapi_encode: grow packet if vaMapBuffer
> returns
> > multiple buffers
> >
> > It seems that VA_CODED_BUF_STATUS_SINGLE_NALU allows driver to
> map
> > buffer for each slice.
> >
> > Currently, assigning new buffer for pkt when multiple buffer returns
> > from vaMapBuffer will cover the previous encoded pkt data and lead
> > to encode issues.
> >
> > Iterate through the buf_list first to find out the total buffer size
> > needed for the pkt, allocate the whole pkt to avoid repeated reallocation
> > and memcpy, then copy data from each buf to pkt.
> >
> > Signed-off-by: Linjie Fu <linjie.fu at intel.com>
> > ---
> > [v2]: allocate the whole pkt to avoid repeated reallocation
> > and memcpy
> >
> >  libavcodec/vaapi_encode.c | 18 +++++++++++++-----
> >  1 file changed, 13 insertions(+), 5 deletions(-)
> >
> > diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
> > index 2dda451..9c9e5dd 100644
> > --- a/libavcodec/vaapi_encode.c
> > +++ b/libavcodec/vaapi_encode.c
> > @@ -489,6 +489,8 @@ static int vaapi_encode_output(AVCodecContext
> > *avctx,
> >      VAAPIEncodeContext *ctx = avctx->priv_data;
> >      VACodedBufferSegment *buf_list, *buf;
> >      VAStatus vas;
> > +    int total_size = 0;
> > +    uint8_t *ptr;
> >      int err;
> >
> >      err = vaapi_encode_wait(avctx, pic);
> > @@ -505,15 +507,21 @@ static int vaapi_encode_output(AVCodecContext
> > *avctx,
> >          goto fail;
> >      }
> >
> > +    for (buf = buf_list; buf; buf = buf->next)
> > +        total_size += buf->size;
> > +
> > +    err = av_new_packet(pkt, total_size);
> > +    ptr = pkt->data;
> > +
> > +    if (err < 0)
> > +        goto fail_mapped;
> > +
> >      for (buf = buf_list; buf; buf = buf->next) {
> >          av_log(avctx, AV_LOG_DEBUG, "Output buffer: %u bytes "
> >                 "(status %08x).\n", buf->size, buf->status);
> >
> > -        err = av_new_packet(pkt, buf->size);
> > -        if (err < 0)
> > -            goto fail_mapped;
> > -
> > -        memcpy(pkt->data, buf->buf, buf->size);
> > +        memcpy(ptr, buf->buf, buf->size);
> > +        ptr += buf->size;
> >      }
> >
> >      if (pic->type == PICTURE_TYPE_IDR)
> > --
> > 2.7.4
> 
> Ping?
> This can fix the encoding issue for vaapi_vp8:
> ffmpeg -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -v verbose -f
> rawvideo -pix_fmt yuv420p -s:v 1280x720 -i ./input_I420.yuv -vf
> 'format=nv12,hwupload' -c:v vp8_vaapi -rc_mode CQP -g 1 -global_quality 14
> -loop_filter_sharpness 0 -loop_filter_level 0 -vframes 10 -y out.ivf

Media driver will return 2 buffers in fact. The first buffer is VACodedBufferSegment
buffer which includes encoded output. And the second buffer is extra VACodedBufferVP9Status.
https://github.com/intel/media-driver/issues/624

Fixes vp8 encoding issues for core platforms(Kaby Lake) and could be verified.
Ping?

- linjie