message: imgcodecs: fix webp IMREAD_GRAYSCALE loading
diff: @@ -162,6 +162,8 @@ bool WebPDecoder::readData(Mat &img)
  {
  if( m_width > 0 && m_height > 0 )
  {
  + bool convert_grayscale = (img.type() == CV_8UC1); // IMREAD_GRAYSCALE requested
  +
  if (img.cols != m_width || img.rows != m_height || img.type() != m_type)
  {
  img.create(m_height, m_width, m_type);
  @@ -184,6 +186,10 @@ bool WebPDecoder::readData(Mat &img)
  if(res_ptr == out_data)
  {
  + if (convert_grayscale)
  + {
  + cvtColor(img, img, COLOR_BGR2GRAY);
  + }
  return true;
  }
  }
  