[FFmpeg-devel] [PATCH] libavutil/hwcontext_qsv: clean padding when upload qsv frames

Xiang, Haihao haihao.xiang at intel.com
Thu Dec 9 10:39:38 EET 2021


On Thu, 2021-12-02 at 15:40 +0800, Wenbin Chen wrote:
> When we upload a frame that is not padded as MSDK requires, we create a
> new AVFrame to copy data. The frame's padding data is uninitialized so
> it brings run to run problem. For example, If we run the following
> command serveral times we will get different outputs.
> 
> ffmpeg -init_hw_device qsv=qsv:hw -qsv_device /dev/dri/renderD128
> -filter_hw_device qsv -f rawvideo -s 192x200 -pix_fmt p010
> -i 192x200_P010.yuv -vf "format=nv12,hwupload=extra_hw_frames=16"
> -c:v hevc_qsv output.265
> 
> According to 
> https://github.com/Intel-Media-SDK/MediaSDK/blob/master/doc/mediasdk-man.md#encoding-procedures
> "Note: It is the application's responsibility to fill pixels outside
> of crop window when it is smaller than frame to be encoded. Especially
> in cases when crops are not aligned to minimum coding block size (16
> for AVC, 8 for HEVC and VP9)"
> 
> I add a function to fill padding area with border pixel to fix this
> run2run problem, and also move the new AVFrame to global structure
> to reduce redundant allocation operation to increase preformance.
> 
> Signed-off-by: Wenbin Chen <wenbin.chen at intel.com>
> ---
>  libavutil/hwcontext_qsv.c | 96 +++++++++++++++++++++++++++++++++------
>  1 file changed, 83 insertions(+), 13 deletions(-)
> 
> diff --git a/libavutil/hwcontext_qsv.c b/libavutil/hwcontext_qsv.c
> index 268be9f8a1..983494666b 100644
> --- a/libavutil/hwcontext_qsv.c
> +++ b/libavutil/hwcontext_qsv.c
> @@ -47,6 +47,7 @@
>  #include "pixfmt.h"
>  #include "pixdesc.h"
>  #include "time.h"
> +#include "imgutils.h"
>  
>  #define QSV_VERSION_ATLEAST(MAJOR, MINOR)   \
>      (MFX_VERSION_MAJOR > (MAJOR) ||         \
> @@ -90,6 +91,7 @@ typedef struct QSVFramesContext {
>  
>      mfxExtOpaqueSurfaceAlloc opaque_alloc;
>      mfxExtBuffer *ext_buffers[1];
> +    AVFrame realigned_tmp_frame;
>  } QSVFramesContext;
>  
>  static const struct {
> @@ -137,6 +139,54 @@ static uint32_t qsv_get_d3d11va_bind_flags(int mem_type)
>  }
>  #endif
>  
> +static int qsv_fill_border(AVFrame *dst, const AVFrame *src)
> +{
> +    const AVPixFmtDescriptor *desc;
> +    int i, planes_nb = 0;
> +    if (dst->format != src->format)
> +        return AVERROR(EINVAL);
> +
> +    desc = av_pix_fmt_desc_get(dst->format);
> +
> +    for (i = 0; i < desc->nb_components; i++)
> +        planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
> +
> +    for (i = 0; i < planes_nb; i++) {
> +        int sheight, dheight, y;
> +        ptrdiff_t swidth = av_image_get_linesize(src->format,
> +                                                 src->width,
> +                                                 i);
> +        ptrdiff_t dwidth = av_image_get_linesize(dst->format,
> +                                                 dst->width,
> +                                                 i);
> +        const AVComponentDescriptor comp = desc->comp[i];
> +        if (swidth < 0 || dwidth < 0) {
> +            av_log(NULL, AV_LOG_ERROR, "av_image_get_linesize failed\n");
> +            return AVERROR(EINVAL);
> +        }
> +        sheight = src->height;
> +        dheight = dst->height;
> +        if (i) {
> +            sheight = AV_CEIL_RSHIFT(src->height, desc->log2_chroma_h);
> +            dheight = AV_CEIL_RSHIFT(dst->height, desc->log2_chroma_h);
> +        }
> +        //fill right padding
> +        for (y = 0; y < sheight; y++) {
> +            void *line_ptr = dst->data[i] + y*dst->linesize[i] + swidth;
> +            av_memcpy_backptr(line_ptr,
> +                           comp.depth > 8 ? 2 : 1,
> +                           dwidth - swidth);
> +        }
> +        //fill bottom padding
> +        for (y = sheight; y < dheight; y++) {
> +            memcpy(dst->data[i]+y*dst->linesize[i],
> +                   dst->data[i]+(sheight-1)*dst->linesize[i],
> +                   dwidth);
> +        }
> +    }
> +    return 0;
> +}
> +
>  static int qsv_device_init(AVHWDeviceContext *ctx)
>  {
>      AVQSVDeviceContext *hwctx = ctx->hwctx;
> @@ -220,6 +270,7 @@ static void qsv_frames_uninit(AVHWFramesContext *ctx)
>      av_freep(&s->surface_ptrs);
>      av_freep(&s->surfaces_internal);
>      av_freep(&s->handle_pairs_internal);
> +    av_frame_unref(&s->realigned_tmp_frame);
>      av_buffer_unref(&s->child_frames_ref);
>  }
>  
> @@ -1014,12 +1065,13 @@ static int qsv_transfer_data_to(AVHWFramesContext
> *ctx, AVFrame *dst,
>      QSVFramesContext   *s = ctx->internal->priv;
>      mfxFrameSurface1   in = {{ 0 }};
>      mfxFrameSurface1 *out = (mfxFrameSurface1*)dst->data[3];
> +    mfxFrameInfo tmp_info;
>  
>      mfxSyncPoint sync = NULL;
>      mfxStatus err;
>      int ret = 0;
>      /* make a copy if the input is not padded as libmfx requires */
> -    AVFrame tmp_frame;
> +    AVFrame *tmp_frame = &s->realigned_tmp_frame;
>      const AVFrame *src_frame;
>      int realigned = 0;
>  
> @@ -1048,24 +1100,40 @@ static int qsv_transfer_data_to(AVHWFramesContext
> *ctx, AVFrame *dst,
>      if (ret < 0)
>          return ret;
>  
> +    /* According to MSDK spec for mfxframeinfo, "Width must be a multiple of
> 16.
> +     * Height must be a multiple of 16 for progressive frame sequence and a
> +     * multiple of 32 otherwise.", so allign all frames to 16 before
> uploading. */
>      if (src->height & 15 || src->linesize[0] & 15) {
>          realigned = 1;
> -        memset(&tmp_frame, 0, sizeof(tmp_frame));
> -        tmp_frame.format         = src->format;
> -        tmp_frame.width          = FFALIGN(src->width, 16);
> -        tmp_frame.height         = FFALIGN(src->height, 16);
> -        ret = av_frame_get_buffer(&tmp_frame, 0);
> -        if (ret < 0)
> +        if (tmp_frame->format != src->format ||
> +            tmp_frame->width  != FFALIGN(src->width, 16) ||
> +            tmp_frame->height != FFALIGN(src->height, 16)) {
> +            av_frame_unref(tmp_frame);
> +
> +            tmp_frame->format = src->format;
> +            tmp_frame->width  = FFALIGN(src->width, 16);
> +            tmp_frame->height = FFALIGN(src->height, 16);
> +            ret = av_frame_get_buffer(tmp_frame, 0);
> +            if (ret < 0)
> +                return ret;
> +        }
> +        ret = av_frame_copy(tmp_frame, src);
> +        if (ret < 0) {
> +            av_frame_unref(tmp_frame);
>              return ret;
> -
> -        ret = av_frame_copy(&tmp_frame, src);
> +        }
> +        ret = qsv_fill_border(tmp_frame, src);
>          if (ret < 0) {
> -            av_frame_unref(&tmp_frame);
> +            av_frame_unref(tmp_frame);
>              return ret;
>          }
> +
> +        tmp_info = out->Info;
> +        out->Info.CropW = FFMIN(out->Info.Width,  tmp_frame->width);
> +        out->Info.CropH = FFMIN(out->Info.Height, tmp_frame->height);
>      }
>  
> -    src_frame = realigned ? &tmp_frame : src;
> +    src_frame = realigned ? tmp_frame : src;
>  
>      if (!s->session_upload) {
>          if (s->child_frames_ref)
> @@ -1097,8 +1165,10 @@ static int qsv_transfer_data_to(AVHWFramesContext *ctx,
> AVFrame *dst,
>          return AVERROR_UNKNOWN;
>      }
>  
> -    if (realigned)
> -        av_frame_unref(&tmp_frame);
> +    if (realigned) {
> +        out->Info.CropW = tmp_info.CropW;
> +        out->Info.CropH = tmp_info.CropH;
> +    }
> 
> 
>      return 0;
>  }

Thanks for this old issue, LGTM 

-Haihao




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