[FFmpeg-devel] [PATCH] hwcontext_vdpau: implement av_hwdevice_get_hwframe_constraints()

[wm4]

On Mon, 15 Jan 2018 11:34:30 +0000
Mark Thompson <sw at jkqxz.net> wrote:

> On 15/01/18 11:22, wm4 wrote:
> > On Mon, 15 Jan 2018 11:17:39 +0000
> > Mark Thompson <sw at jkqxz.net> wrote:
> >   
> >> On 13/01/18 06:06, wm4 wrote:  
> >>> In addition, this does not allow creating frames contexts with sw_format
> >>> for which no known transfer formats exist. In theory, we should check
> >>> whether the chroma format (i.e. the sw_format) is supported at all by
> >>> the vdpau driver, but checking for transfer formats has the same effect.
> >>>
> >>> Note that the pre-existing code adds 1 to priv->nb_pix_fmts[i] for
> >>> unknown reason, and some checks need to account for that to check for
> >>> empty lists. They are not off-by-one errors.
> >>> ---
> >>>  libavutil/hwcontext_vdpau.c | 55 ++++++++++++++++++++++++++++++++-------------
> >>>  1 file changed, 39 insertions(+), 16 deletions(-)
> >>>
> >>> diff --git a/libavutil/hwcontext_vdpau.c b/libavutil/hwcontext_vdpau.c
> >>> index 9b8f839647..c11c3cfdab 100644
> >>> --- a/libavutil/hwcontext_vdpau.c
> >>> +++ b/libavutil/hwcontext_vdpau.c
> >>> @@ -79,11 +79,12 @@ static const VDPAUPixFmtMap pix_fmts_444[] = {
> >>>  
> >>>  static const struct {
> >>>      VdpChromaType chroma_type;
> >>> +    enum AVPixelFormat frames_sw_format;
> >>>      const VDPAUPixFmtMap *map;
> >>>  } vdpau_pix_fmts[] = {
> >>> -    { VDP_CHROMA_TYPE_420, pix_fmts_420 },
> >>> -    { VDP_CHROMA_TYPE_422, pix_fmts_422 },
> >>> -    { VDP_CHROMA_TYPE_444, pix_fmts_444 },
> >>> +    { VDP_CHROMA_TYPE_420, AV_PIX_FMT_YUV420P, pix_fmts_420 },
> >>> +    { VDP_CHROMA_TYPE_422, AV_PIX_FMT_YUV422P, pix_fmts_422 },
> >>> +    { VDP_CHROMA_TYPE_444, AV_PIX_FMT_YUV444P, pix_fmts_444 },
> >>>  };
> >>>  
> >>>  static int count_pixfmts(const VDPAUPixFmtMap *map)
> >>> @@ -170,6 +171,35 @@ static void vdpau_device_uninit(AVHWDeviceContext *ctx)
> >>>          av_freep(&priv->pix_fmts[i]);
> >>>  }
> >>>  
> >>> +static int vdpau_frames_get_constraints(AVHWDeviceContext *ctx,
> >>> +                                        const void *hwconfig,
> >>> +                                        AVHWFramesConstraints *constraints)
> >>> +{
> >>> +    VDPAUDeviceContext   *priv  = ctx->internal->priv;
> >>> +    int nb_sw_formats = 0;
> >>> +    int i;
> >>> +
> >>> +    constraints->valid_sw_formats = av_malloc_array(FF_ARRAY_ELEMS(vdpau_pix_fmts) + 1,
> >>> +                                                    sizeof(*constraints->valid_sw_formats));
> >>> +    if (!constraints->valid_sw_formats)
> >>> +        return AVERROR(ENOMEM);
> >>> +
> >>> +    for (i = 0; i < FF_ARRAY_ELEMS(vdpau_pix_fmts); i++) {
> >>> +        if (priv->nb_pix_fmts[i] > 1)
> >>> +            constraints->valid_sw_formats[nb_sw_formats++] = vdpau_pix_fmts[i].frames_sw_format;
> >>> +    }
> >>> +    constraints->valid_sw_formats[nb_sw_formats] = AV_PIX_FMT_NONE;
> >>> +
> >>> +    constraints->valid_hw_formats = av_malloc_array(2, sizeof(*constraints->valid_hw_formats));
> >>> +    if (!constraints->valid_hw_formats)
> >>> +        return AVERROR(ENOMEM);
> >>> +
> >>> +    constraints->valid_hw_formats[0] = AV_PIX_FMT_VDPAU;
> >>> +    constraints->valid_hw_formats[1] = AV_PIX_FMT_NONE;
> >>> +
> >>> +    return 0;
> >>> +}
> >>> +
> >>>  static void vdpau_buffer_free(void *opaque, uint8_t *data)
> >>>  {
> >>>      AVHWFramesContext          *ctx = opaque;
> >>> @@ -214,26 +244,18 @@ static int vdpau_frames_init(AVHWFramesContext *ctx)
> >>>  
> >>>      int i;
> >>>  
> >>> -    switch (ctx->sw_format) {
> >>> -    case AV_PIX_FMT_YUV420P: priv->chroma_type = VDP_CHROMA_TYPE_420; break;
> >>> -    case AV_PIX_FMT_YUV422P: priv->chroma_type = VDP_CHROMA_TYPE_422; break;
> >>> -    case AV_PIX_FMT_YUV444P: priv->chroma_type = VDP_CHROMA_TYPE_444; break;
> >>> -    default:
> >>> -        av_log(ctx, AV_LOG_ERROR, "Unsupported data layout: %s\n",
> >>> -               av_get_pix_fmt_name(ctx->sw_format));
> >>> -        return AVERROR(ENOSYS);
> >>> -    }
> >>> -
> >>>      for (i = 0; i < FF_ARRAY_ELEMS(vdpau_pix_fmts); i++) {
> >>> -        if (vdpau_pix_fmts[i].chroma_type == priv->chroma_type) {
> >>> +        if (vdpau_pix_fmts[i].frames_sw_format == ctx->sw_format) {
> >>> +            priv->chroma_type = vdpau_pix_fmts[i].chroma_type;
> >>>              priv->chroma_idx  = i;
> >>>              priv->pix_fmts    = device_priv->pix_fmts[i];
> >>>              priv->nb_pix_fmts = device_priv->nb_pix_fmts[i];
> >>>              break;
> >>>          }
> >>>      }
> >>> -    if (!priv->pix_fmts) {
> >>> -        av_log(ctx, AV_LOG_ERROR, "Unsupported chroma type: %d\n", priv->chroma_type);
> >>> +    if (priv->nb_pix_fmts < 2) {    
> >>
> >> I think keeping the (equivalent) older check of !priv->pix_fmts would look slightly clearer?  
> > 
> > I don't think that would be the same. Checking priv->pix_fmts tells you
> > that there was a matching chroma type, but checking nb_pix_fmts < 2
> > tells you in addition whether there is any working sw_format. That in
> > turn is needed to tell whether the vdpau implementation supports the
> > chroma format at all.  
> 
> Right, priv->pix_fmts could be a valid list containing nothing.  Then yes, use your way.

Thanks for the review, pushed.