[FFmpeg-devel] [PATCH] libavutil/hwcontext_qsv: Command line using hwaccel 'QSV' doesn't work

[Mark Thompson]

On 06/01/17 06:37, Huang, Zhengxu wrote:
> Hi
> 
> According to the suggestion update the patch.
> 
> thanks.
> 
> 
> From 4beadd3c84c797a56c4f375458d0a1e9d9b233c8 Mon Sep 17 00:00:00 2001
> From: Zhengxu <zhengxu.maxwell at gmail.com>
> Date: Thu, 5 Jan 2017 14:48:06 +0800
> Subject: [PATCH] ffmpeg_qsv: Add an option "qsv_child_device" to choose an
>  proper node for QSV child device(vaapi or dxva2).
> 
> Reason: For some cases, such as 2 or more graphics card existing, the
> default command line may fail because ffmpeg open a wrong device node:
>     ffmpeg -hwaccel qsv -c:v h264_qsv -i test.264 -c:v h264_qsv out.264
> Let user to choose the proper one by running like below:
>     ffmpeg -hwaccel qsv -qsv_child_device /dev/dri/renderD128 -c:v h264_qsv \
> -i test.264 -c:v h264_qsv out.264

I think it should just be "qsv_device".  It is the device being used by qsv, the fact that it is a child device of another kind (dxva or vaapi) wrapped inside the hwcontext infrastructure isn't really relevant to the ffmpeg utility.

> 
> Signed-off-by: ChaoX A Liu <chaox.a.liu at gmail.com>
> Signed-off-by: Huang, Zhengxu <zhengxu.maxwell at gmail.com>
> Signed-off-by: Andrew, Zhang <huazh407 at gmail.com>
> ---
>  ffmpeg.h     |  3 +++
>  ffmpeg_opt.c |  5 +++++
>  ffmpeg_qsv.c | 11 ++++++++++-
>  3 files changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/ffmpeg.h b/ffmpeg.h
> index ebe5bf0..91a3333 100644
> --- a/ffmpeg.h
> +++ b/ffmpeg.h
> @@ -602,6 +602,9 @@ extern const OptionDef options[];
>  extern const HWAccel hwaccels[];
>  extern int hwaccel_lax_profile_check;
>  extern AVBufferRef *hw_device_ctx;
> +#if CONFIG_QSV
> +extern char *qsv_child_device;
> +#endif
>  
>  
>  void term_init(void);
> diff --git a/ffmpeg_opt.c b/ffmpeg_opt.c
> index 6862456..7fd08a2 100644
> --- a/ffmpeg_opt.c
> +++ b/ffmpeg_opt.c
> @@ -3679,5 +3679,10 @@ const OptionDef options[] = {
>          "set VAAPI hardware device (DRM path or X11 display name)", "device" },
>  #endif
>  
> +#if CONFIG_QSV
> +    { "qsv_child_device", HAS_ARG | OPT_STRING | OPT_EXPERT, { &qsv_child_device },
> +        "set QSV child device (DRM path or DXVA)", "device"},

An X11 display will still work here.  Also, maybe clarify that the DXVA case is a DirectX adapter index?

"set QSV hardware device (DirectX adapter index, DRM path or X11 display name)", say.

> +#endif
> +
>      { NULL, },
>  };
> diff --git a/ffmpeg_qsv.c b/ffmpeg_qsv.c
> index 68ff5bd..5a6db20 100644
> --- a/ffmpeg_qsv.c
> +++ b/ffmpeg_qsv.c
> @@ -28,6 +28,8 @@
>  
>  #include "ffmpeg.h"
>  
> +char *qsv_child_device = NULL;
> +
>  static int qsv_get_buffer(AVCodecContext *s, AVFrame *frame, int flags)
>  {
>      InputStream *ist = s->opaque;
> @@ -44,9 +46,16 @@ static void qsv_uninit(AVCodecContext *s)
>  static int qsv_device_init(InputStream *ist)
>  {
>      int err;
> +    AVDictionary *dict = NULL;
> +
> +    if (qsv_child_device) {
> +        err = av_dict_set(&dict, "child_device", qsv_child_device, 0);
> +        if (err < 0)
> +            return err;
> +    }
>  
>      err = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_QSV,
> -                                 ist->hwaccel_device, NULL, 0);
> +                                 ist->hwaccel_device, dict, 0);
>      if (err < 0) {
>          av_log(NULL, AV_LOG_ERROR, "Error creating a QSV device\n");
>          return err;
> -- 
> 1.8.3.1
> 

Patch otherwise ok.

Thanks,

- Mark