221 read_user_callback(png_structp png_ptr, png_row_infop row_info, png_bytep data)  in read_user_callback()  argument
224    PNG_UNUSED(row_info)  in read_user_callback()
237 count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)  in count_zero_samples()  argument
254     if (row_info->color_type == 0 || row_info->color_type == 3)  in count_zero_samples()
259        for (n = 0, nstop=row_info->width; n<nstop; n++)  in count_zero_samples()
261           if (row_info->bit_depth == 1)  in count_zero_samples()
273           if (row_info->bit_depth == 2)  in count_zero_samples()
285           if (row_info->bit_depth == 4)  in count_zero_samples()
297           if (row_info->bit_depth == 8)  in count_zero_samples()
301           if (row_info->bit_depth == 16)  in count_zero_samples()
313        int color_channels = row_info->channels;  in count_zero_samples()
314        if (row_info->color_type > 3)  in count_zero_samples()
317        for (n = 0, nstop=row_info->width; n<nstop; n++)  in count_zero_samples()
321              if (row_info->bit_depth == 8)  in count_zero_samples()
325              if (row_info->bit_depth == 16)  in count_zero_samples()
333           if (row_info->color_type > 3)  in count_zero_samples()
336              if (row_info->bit_depth == 16)  in count_zero_samples()