[FFmpeg-devel] [PATCH 00/15] OpenCL infrastructure, filters

Mark Thompson sw at jkqxz.net
Tue Nov 14 21:47:15 EET 2017


Changes since the last time this was posted:
* Add unsharp filter (to replace existing unsharp).
* Remove old experimental API.
* Miscellaneous fixes.

Now also tested with AMD OpenCL on Windows (DXVA2 mapping works nicely, D3D11 does not because it wants the Intel extension for NV12 support).

Thanks,

- Mark


Silly example using everything (for i965 VAAPI + Beignet):

./ffmpeg_g -y -init_hw_device vaapi=va:/dev/dri/renderD128 -init_hw_device opencl=ocl at va -hwaccel vaapi -hwaccel_device va -hwaccel_output_format vaapi -i in.mp4 -f image2 -r 1 -i overlays/%d.png -an -filter_hw_device ocl -filter_complex '[1:v]format=yuva420p,hwupload[x2]; [0:v]scale_vaapi=1280:720:yuv420p,hwmap[x1]; [x1][x2]overlay_opencl=0:0,program_opencl=test.cl:rotate_image,unsharp_opencl=lx=17:ly=17:la=5,hwmap=derive_device=vaapi:reverse=1,scale_vaapi=1280:720:nv12' -c:v h264_vaapi -frames:v 1000 out.mp4

test.cl:

__kernel void rotate_image(__write_only image2d_t dst,
                           __read_only  image2d_t src,
                           unsigned int index)
{
  const sampler_t sampler = (CLK_NORMALIZED_COORDS_FALSE |
                             CLK_FILTER_LINEAR);

  float angle = (float)index / 100;

  float2 dst_dim = convert_float2(get_image_dim(dst));
  float2 src_dim = convert_float2(get_image_dim(src));

  float2 dst_cen = dst_dim / 2;
  float2 src_cen = src_dim / 2;

  int2   dst_loc = (int2)(get_global_id(0), get_global_id(1));

  float2 dst_pos = convert_float2(dst_loc) - dst_cen;
  float2 src_pos = {
    cos(angle) * dst_pos.x - sin(angle) * dst_pos.y,
    sin(angle) * dst_pos.x + cos(angle) * dst_pos.y
  };
  src_pos = src_pos * src_dim / dst_dim;

  float2 src_loc = src_pos + src_cen;

  if (src_loc.x < 0         || src_loc.y < 0 ||
      src_loc.x > src_dim.x || src_loc.y > src_dim.y)
    write_imagef(dst, dst_loc, 0.5);
  else
    write_imagef(dst, dst_loc, read_imagef(src, sampler, src_loc));
}


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