small bugfixes about transparency

[libucw.git] / images / images.h

diff --git a/images/images.h b/images/images.h
index 8300c3cc77386413e4c7bdf18659b89567b63b3a..282489fd7a1ddb88378296fd06be4a4769311b19 100644 (file)
--- a/images/images.h
+++ b/images/images.h
@@ -94,11 +94,20 @@ byte *color_space_to_name(enum color_space cs);
 byte *image_channels_format_to_name(uns format);
 uns image_name_to_channels_format(byte *name);
 
+struct color {
+  byte c[3];
+  byte color_space;
+} PACKED;
+
 /* scale.c */
 
 int image_scale(struct image_thread *thread, struct image *dest, struct image *src);
 void image_dimensions_fit_to_box(u32 *cols, u32 *rows, u32 max_cols, u32 max_rows, uns upsample);
 
+/* alpha.c */
+
+int image_apply_background(struct image_thread *thread, struct image *dest, struct image *src, struct color *background);
+
 /* image-io.c */
 
 enum image_format {
@@ -125,6 +134,7 @@ struct image_io {
   u32 flags;                           /* [ HI  ] - see enum image_io_flags */
   u32 jpeg_quality;                    /* [    W] - JPEG compression quality (1..100) */
   u32 number_of_colors;                        /* [ H   ] - number of image colors */
+  struct color background_color;       /* [ HI  ] - background color, zero if undefined */
 
   /* internals */
   struct image_thread *thread;
@@ -135,8 +145,9 @@ struct image_io {
 };
 
 enum image_io_flags {
-  IMAGE_IO_IMAGE_FLAGS = 0xffff,       /* [ HI  ] - parameter to image new, read_header fills IMAGE_CHANNELS_FORMAT */
+  IMAGE_IO_IMAGE_FLAGS = 0xffff,       /* [ HI  ] - mask of parameters to image new, read_header fills IMAGE_CHANNELS_FORMAT */
   IMAGE_IO_HAS_PALETTE = 0x10000,      /* [ H   ] - true for image with indexed colors */
+  IMAGE_IO_USE_BACKGROUND = 0x20000,   /* [  I  ] - merge transparent pixels with background_color */
 };
 
 void image_io_init(struct image_thread *it, struct image_io *io);