[FFmpeg-devel] [PATCH v2] avfilter: add QSV variants of the stack filters

[Soft Works]

> -----Original Message-----
> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> Haihao Xiang
> Sent: Wednesday, 4 August 2021 10:33
> To: ffmpeg-devel at ffmpeg.org
> Cc: Haihao Xiang <haihao.xiang at intel.com>
> Subject: [FFmpeg-devel] [PATCH v2] avfilter: add QSV variants of the stack
> filters
> 
> Include hstack_qsv, vstack_qsv and xstack_qsv, some code is copy and
> pasted from other filters
> 
> Example:
> $> ffmpeg -hwaccel qsv -c:v hevc_qsv -i input.h265 -filter_complex
> "[0:v][0:v]hstack_qsv" -f null -
> ---

[...]

> +
> +/*
> + * Callback for qsvvpp
> + * @Note: qsvvpp composition does not generate PTS for result frame.
> + *        so we assign the PTS from framesync to the output frame.
> + */
> +
> +static int filter_callback(AVFilterLink *outlink, AVFrame *frame)
> +{
> +    QSVStackContext *sctx = outlink->src->priv;
> +
> +    frame->pts = av_rescale_q(sctx->fs.pts,
> +                              sctx->fs.time_base, outlink->time_base);
> +    return ff_filter_frame(outlink, frame);
> +}

If the surface.Data.TimeStamp gets overwritten by libMFX, why not copy 
the PTS from the input frame in ff_qsvvpp_filter_frame ?

That would apply the timestamp from the last input, though. Preferably would it
be taken from the first input instead. For 2-n, you could perhaps clone the frames and 
assign the pts from the first input's frame?

softworkz