[babl] add API for managing palette based formats

[Ãyvind KolÃs <ok src gnome org>]

commit 47f3c99e1c58bb50e60d03727c2b2cdcef363cbf
Author: Ãyvind KolÃs <pippin gimp org>
Date:   Sat Mar 17 12:22:10 2012 +0000

    add API for managing palette based formats

 babl/Makefile.am      |    1 +
 babl/babl-ids.h       |    1 +
 babl/babl-types.h     |    8 +++-
 babl/babl.h           |   21 +++++++++
 babl/base/babl-base.h |    1 +
 tests/Makefile.am     |    3 +-
 tests/palette.c       |  108 +++++++++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 139 insertions(+), 4 deletions(-)
---
diff --git a/babl/Makefile.am b/babl/Makefile.am
index 93c2657..cefab57 100644
--- a/babl/Makefile.am
+++ b/babl/Makefile.am
@@ -27,6 +27,7 @@ c_sources =				\
 	babl-memory.c			\
 	babl-model.c			\
 	babl-mutex.c			\
+	babl-palette.c    \
 	babl-sampling.c			\
 	babl-sanity.c			\
 	babl-type.c			\
diff --git a/babl/babl-ids.h b/babl/babl-ids.h
index f0f6c61..f26add8 100644
--- a/babl/babl-ids.h
+++ b/babl/babl-ids.h
@@ -85,6 +85,7 @@ enum {
   BABL_CB,
   BABL_CR,
   BABL_PADDING,
+  BABL_PAL,
   BABL_COMPONENT_LAST_INTERNAL,
 
   BABL_FORMAT_BASE = 100000,
diff --git a/babl/babl-types.h b/babl/babl-types.h
index 7871e3b..ea30b7f 100644
--- a/babl/babl-types.h
+++ b/babl/babl-types.h
@@ -35,7 +35,9 @@ typedef union _Babl Babl;
  */
 typedef long (*BablFuncLinear)    (const char  *src,
                                    char  *dst,
-                                   long   n);
+                                   long   n,
+                                   void  *src_model_data,
+                                   void  *dst_model_data);
 
 /* TypePlanar,ModelPlanar and FormatPlanar */
 typedef long (*BablFuncPlanar)    (int    src_bands,
@@ -44,6 +46,8 @@ typedef long (*BablFuncPlanar)    (int    src_bands,
                                    int    dst_bands,
                                    char  *dst[],
                                    int    dst_pitch[],
-                                   long   n);
+                                   long   n,
+                                   void  *src_model_data,
+                                   void  *dst_model_data);
 
 #endif
diff --git a/babl/babl.h b/babl/babl.h
index 49110d3..e4b0082 100644
--- a/babl/babl.h
+++ b/babl/babl.h
@@ -200,6 +200,27 @@ int babl_format_is_format_n (Babl *format);
 Babl * babl_conversion_new (void *first_arg,
                             ...) BABL_ARG_NULL_TERMINATED;
 
+/**
+ * create a new palette based format, name is optional pass in NULL to get
+ * an anonymous format.
+ */
+Babl *babl_new_palette         (const char *name);
+
+/**
+ * Assign a palette to a palette format, the data is a single span of pixels
+ * representing the colors of the palette.
+ */
+void  babl_palette_set_palette (Babl              *babl,
+                                Babl              *format,
+                                void              *data,
+                                int                count);
+
+/**
+ * reset a palette to initial state.
+ */
+void  babl_palette_reset       (Babl              *babl);
+
+
 
 /*
  * Backwards compatibility stuff
diff --git a/babl/base/babl-base.h b/babl/base/babl-base.h
index 57d4ceb..bed3c64 100644
--- a/babl/base/babl-base.h
+++ b/babl/base/babl-base.h
@@ -28,6 +28,7 @@ void babl_base_type_u8     (void);
 void babl_base_type_u16    (void);
 void babl_base_type_u32    (void);
 
+void babl_base_model_pal   (void);
 void babl_base_model_rgb   (void);
 void babl_base_model_gray  (void);
 void babl_base_model_ycbcr (void);
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 8b9060d..ba88a9c 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -10,6 +10,7 @@ TESTS =				\
 	sanity			\
 	babl_class_name		\
 	types			\
+	palette \
 	extract \
 	nop \
 	n_components		\
@@ -33,6 +34,4 @@ noinst_PROGRAMS =		\
 	babl-html-dump		\
 	conversions		\
 	formats			\
-	extract \
-	nop			\
 	$(TESTS)
diff --git a/tests/palette.c b/tests/palette.c
new file mode 100644
index 0000000..02f79ac
--- /dev/null
+++ b/tests/palette.c
@@ -0,0 +1,108 @@
+/* babl - dynamically extendable universal pixel conversion library.
+ * Copyright (C) 2005, Ãyvind KolÃs.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include "babl.h"
+
+
+#define CHECK_CONV(test_name, componenttype, src_fmt, dst_fmt, src_pix, expected_pix) \
+  {       \
+  Babl *fish;       \
+  int i;       \
+  fish = babl_fish (src_fmt, dst_fmt);       \
+  if (!fish)       \
+    {       \
+      printf ("  %s failed to make fish\n", test_name);       \
+      OK = 0;       \
+    }       \
+  for (i = 0; i < sizeof(src_pix)/sizeof(src_pix[0]); i ++)       \
+    {       \
+      int c;\
+      componenttype result[10];       \
+      babl_process (fish, src_pix[i], result, 1);       \
+      for (c = 0; c < sizeof(expected_pix[i])/sizeof(expected_pix[i][0]); c++) \
+      if (result[c] != expected_pix[i][c])       \
+        {       \
+          printf (" %s failed #%i[%i]  got %i expected %i\n", test_name, i, c, result[c], expected_pix[i][c]);       \
+          OK = 0;          \
+        }       \
+    }       \
+  }
+
+
+int
+main (int    argc,
+      char **argv)
+{
+  int OK = 1;
+  babl_init ();
+
+  {
+    unsigned char in[][1]   = {{        0},{          1},{          2},{15}};
+    unsigned char out[][4]  = {{0,0,0,255},{127,0,0,255},{0,127,0,255},{255,255,255,255}};
+    Babl *palA = babl_new_palette (NULL);
+    Babl *palB = babl_new_palette (NULL);
+
+    CHECK_CONV("pal to rgba", unsigned char,
+        palA, babl_format("RGBA u8"),
+        in, out);
+
+    CHECK_CONV("pal to rgba", unsigned char,
+        palB, babl_format("RGBA u8"),
+        in, out);
+
+    CHECK_CONV("pal to rgba", unsigned char,
+        palA, babl_format("RGBA u8"),
+        in, out);
+  }
+
+  {
+    unsigned char in[][4]  = {{0,0,0,255},{140,0,0,255},{0,127,0,255}};
+    unsigned char out[][1] = {{        0},{          1},{          2}};
+
+    CHECK_CONV("rgba to pal", unsigned char,
+         babl_format("RGBA u8"), babl_new_palette ("palC"),
+         in, out);
+  }
+
+  /* check with a custom floating point palette */
+  {
+    float palette[] = {
+      0.5,  1.0,
+      0.23, 0.42,
+      1.0,  0.2
+    };
+
+    unsigned char in[][1]   = {{         0},{          1},{          2}};
+    unsigned char out[][4]  = {{128,128,128,255},{59,59,59,107},{255,255,255,51}};
+
+    Babl *pal = babl_new_palette (NULL);
+
+    babl_palette_set_palette (pal, babl_format ("YA float"), palette, 3);
+
+    CHECK_CONV("rgba to YA float pal", unsigned char,
+         pal, babl_format("RGBA u8"),
+         in, out);
+  }
+
+  babl_exit ();
+  return !OK;
+}