Read a line from an image, and write the values of the
pixel format component c to dst.
@param data the array containing the pointers to the planes of the image
@param linesize the array containing the linesizes of the image
@param desc the pixel format descriptor for the image
@param x the horizontal coordinate of the first pixel to read
@param y the vertical coordinate of the first pixel to read
@param w the width of the line to read, that is the number of
values to write to dst
@param read_pal_component if not zero and the format is a paletted
format writes the values corresponding to the palette
component c in data[1] to dst, rather than the palette indexes in
data[0]. The behavior is undefined if the format is not paletted.
@param dst_element_size size of elements in dst array (2 or 4 byte)
Read a line from an image, and write the values of the pixel format component c to dst.
@param data the array containing the pointers to the planes of the image @param linesize the array containing the linesizes of the image @param desc the pixel format descriptor for the image @param x the horizontal coordinate of the first pixel to read @param y the vertical coordinate of the first pixel to read @param w the width of the line to read, that is the number of values to write to dst @param read_pal_component if not zero and the format is a paletted format writes the values corresponding to the palette component c in data[1] to dst, rather than the palette indexes in data[0]. The behavior is undefined if the format is not paletted. @param dst_element_size size of elements in dst array (2 or 4 byte)