partial YCCK colorspace support

diff --git a/images/color.c b/images/color.c
index 193a0f138477d313734c410901cbc4d2bfc0ff40..ee1525e098847e45de81bb9bcebbb36368f80fb5 100644 (file)
--- a/images/color.c
+++ b/images/color.c
@@ -248,6 +248,47 @@ pixel_conv_rgb_to_cmyk(byte *dest, byte *src)
 #define IMAGE_WALK_DO_STEP do{ pixel_conv_rgb_to_cmyk(walk_pos, walk_sec_pos); }while(0)
 #include "images/image-walk.h"
 
+/* YCCK <-> RGB */
+
+static inline void
+pixel_conv_ycck_to_rgb(byte *dest, byte *src)
+{
+  int y = src[0], cb = src[1] - 128, cr = src[2] - 128;
+  uns d = (255 - src[3]) * (0xffffffffU / 255 /255);
+  dest[0] = (d * CLAMP(y + (91881 * cr) / 0x10000, 0, 255) >> 24);
+  dest[1] = (d * CLAMP(y - (22553 * cb + 46801 * cr) / 0x10000, 0, 255) >> 24);
+  dest[2] = (d * CLAMP(y + (116129 * cb) / 0x10000, 0, 255) >> 24);
+}
+
+#define IMAGE_WALK_PREFIX(x) walk_##x
+#define IMAGE_WALK_FUNC_NAME image_conv_ycck_4_to_rgb_n
+#define IMAGE_WALK_DOUBLE
+#define IMAGE_WALK_SEC_COL_STEP 4
+#define IMAGE_WALK_DO_STEP do{ pixel_conv_ycck_to_rgb(walk_pos, walk_sec_pos); }while(0)
+#include "images/image-walk.h"
+
+static inline void
+pixel_conv_rgb_to_ycck(byte *dest, byte *src)
+{
+  uns k = MAX(src[0], src[1]);
+  k = MAX(k, src[2]);
+  uns d = fast_div_u32_u8(0x7fffffffU, k); /* == 0 for zero K */
+  uns r = 255 - ((d * (k - src[0])) >> 23);
+  uns g = 255 - ((d * (k - src[1])) >> 23);
+  uns b = 255 - ((d * (k - src[2])) >> 23);
+  dest[0] = (19595 * r + 38470 * g + 7471 * b) / 0x10000;
+  dest[1] = (0x800000 + 0x8000 * b - 11058 * r - 21710 * g) / 0x10000;
+  dest[2] = (0x800000 + 0x8000 * r - 27439 * g - 5329 * b) / 0x10000;
+  dest[3] = 255 - k;
+}
+
+#define IMAGE_WALK_PREFIX(x) walk_##x
+#define IMAGE_WALK_FUNC_NAME image_conv_rgb_n_to_ycck_4
+#define IMAGE_WALK_DOUBLE
+#define IMAGE_WALK_COL_STEP 4
+#define IMAGE_WALK_DO_STEP do{ pixel_conv_rgb_to_ycck(walk_pos, walk_sec_pos); }while(0)
+#include "images/image-walk.h"
+
 /* Main functions */
 
 static int
@@ -287,6 +328,13 @@ image_conv_color_space(struct image_context *ctx UNUSED, struct image *dest, str
                  return 1;
                }
              break;
+           case COLOR_SPACE_YCCK:
+             if (src->pixel_size == 4)
+               {
+                 image_conv_ycck_4_to_rgb_n(dest, src);
+                 return 1;
+               }
+             break;
        }
        break;
       case COLOR_SPACE_YCBCR:
@@ -309,6 +357,18 @@ image_conv_color_space(struct image_context *ctx UNUSED, struct image *dest, str
              break;
           }
         break;
+      case COLOR_SPACE_YCCK:
+       switch (src->flags & IMAGE_CHANNELS_FORMAT)
+         {
+           case COLOR_SPACE_RGB:
+             if (dest->pixel_size == 4)
+               {
+                 image_conv_rgb_n_to_ycck_4(dest, src);
+                 return 1;
+               }
+             break;
+         }
+       break;
     }
   return 0;
 }

diff --git a/images/io-libjpeg.c b/images/io-libjpeg.c
index 03952519ee8542a0af5f49f97e8726592e3d5d1e..a3120dfb0dcf987b8c4b7b74d565fba2807cda11 100644 (file)
--- a/images/io-libjpeg.c
+++ b/images/io-libjpeg.c
@@ -358,7 +358,11 @@ libjpeg_read_data(struct image_io *io)
          {
            case JCS_CMYK:
              read_flags = (read_flags & ~IMAGE_COLOR_SPACE & IMAGE_CHANNELS_FORMAT) | COLOR_SPACE_CMYK; 
-             i->cinfo.out_color_space = JCS_YCbCr;
+             i->cinfo.out_color_space = JCS_CMYK;
+             break;
+           case JCS_YCCK:
+             read_flags = (read_flags & ~IMAGE_COLOR_SPACE & IMAGE_CHANNELS_FORMAT) | COLOR_SPACE_YCCK; 
+             i->cinfo.out_color_space = JCS_YCCK;
              break;
            default:
              read_flags = (read_flags & ~IMAGE_COLOR_SPACE & IMAGE_CHANNELS_FORMAT) | COLOR_SPACE_RGB; 
@@ -520,6 +524,7 @@ libjpeg_write(struct image_io *io)
     }
   i.cinfo.input_components = color_space_channels[img->flags & IMAGE_COLOR_SPACE];
   jpeg_set_defaults(&i.cinfo);
+  jpeg_set_colorspace(&i.cinfo, i.cinfo.in_color_space);
   if (io->jpeg_quality)
     jpeg_set_quality(&i.cinfo, MIN(io->jpeg_quality, 100), 1);
   if (io->exif_size)