message: Improve resize_bilinear CPU back-prop kernel comment
diff: @@ -309,9 +309,12 @@ struct ResizeBilinearGrad<CPUDevice, T> {
  output_grad.setZero();
  - // Each resized pixel was computed as a weighted average of four input
  - // pixels. Here we find the pixels that contributed to each output pixel
  - // and add the corresponding coefficient to the gradient.
  + // Each resized output pixel was computed as a weighted average of four
  + // input pixels. Here we find the four input pixel locations that
  + // contributed to each output pixel and propgate the gradient at the output
  + // pixel location to each of those four input pixels locations in the same
  + // proportions that they originally contributed to the output pixel.
  + // Here is the forward-propagation pseudo-code, for reference:
  // resized(b, y, x, c) = top_left * (1 - y) * (1 - x)
  // + top_right * (1 - y) * x
  // + bottom_left * y * (1 - x)
  