diff options
Diffstat (limited to 'gs/toolbin/bmpcmp.c')
| -rw-r--r-- | gs/toolbin/bmpcmp.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/gs/toolbin/bmpcmp.c b/gs/toolbin/bmpcmp.c index 2a82ff485..bcedb7aa7 100644 --- a/gs/toolbin/bmpcmp.c +++ b/gs/toolbin/bmpcmp.c @@ -1015,8 +1015,9 @@ static void *png_read(ImageReader *im, { png_structp png; png_infop info; - int stride, w, h, y; + int stride, w, h, y, x; unsigned char *data; + int expand = 0; /* There is only one image in each file */ if (ftell(im->file) != 0) @@ -1037,9 +1038,12 @@ static void *png_read(ImageReader *im, png_set_expand(png); png_set_packing(png); png_set_strip_16(png); - if (png_get_color_type(png, info) == PNG_COLOR_TYPE_GRAY_ALPHA) + if (png_get_color_type(png, info) == PNG_COLOR_TYPE_GRAY_ALPHA) { png_set_strip_alpha(png); - if (png_get_color_type(png, info) == PNG_COLOR_TYPE_RGB) + expand = 1; + } else if (png_get_color_type(png, info) == PNG_COLOR_TYPE_GRAY) { + expand = 1; + } else if (png_get_color_type(png, info) == PNG_COLOR_TYPE_RGB) png_set_add_alpha(png, 0xff, PNG_FILLER_AFTER); png_read_update_info(png, info); @@ -1047,10 +1051,25 @@ static void *png_read(ImageReader *im, w = png_get_image_width(png, info); h = png_get_image_height(png, info); stride = png_get_rowbytes(png, info); + if (expand) + stride *= sizeof(int); data = malloc(h * stride); - for (y = 0; y < h; y++) - png_read_row(png, data + (h - y - 1) * stride, NULL); + for (y = 0; y < h; y++) { + unsigned char *row = data + (h - y - 1) * stride; + png_read_row(png, row, NULL); + if (expand) { + unsigned char *dst = row + w*sizeof(int); + unsigned char *src = row + w; + for (x = w; x > 0; x--) { + unsigned char c = *--src; + *--dst = 0; + *--dst = c; + *--dst = c; + *--dst = c; + } + } + } png_read_end(png, NULL); png_destroy_read_struct(&png, &info, NULL); |