[babl] add a u15 type that is 16bit only using 15bits

[Jon Nordby <jonnor src gnome org>]

commit 8167d33480d05308b753ad61acaaa17ff2f26c3c
Author: Ãyvind KolÃs <pippin gimp org>
Date:   Thu May 3 01:20:29 2012 +0200

    add a u15 type that is 16bit only using 15bits

 babl/base/Makefile.am  |    1 +
 babl/base/babl-base.c  |    3 +
 babl/base/babl-base.h  |    1 +
 babl/base/model-gray.c |   37 +++++++++++++
 babl/base/model-rgb.c  |   53 +++++++++++++++++++
 babl/base/type-u15.c   |  136 ++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 231 insertions(+), 0 deletions(-)
---
diff --git a/babl/base/Makefile.am b/babl/base/Makefile.am
index 74052c2..55cd1df 100644
--- a/babl/base/Makefile.am
+++ b/babl/base/Makefile.am
@@ -8,6 +8,7 @@ c_sources =			\
 	type-float.c		\
 	type-half.c		\
 	type-u8.c		\
+	type-u15.c		\
 	type-u16.c		\
 	type-u32.c		\
 	model-rgb.c		\
diff --git a/babl/base/babl-base.c b/babl/base/babl-base.c
index 0831eb1..3fe3cfc 100644
--- a/babl/base/babl-base.c
+++ b/babl/base/babl-base.c
@@ -50,6 +50,7 @@ babl_base_destroy (void)
 static void
 types (void)
 {
+  babl_base_type_u15 ();
   babl_base_type_half ();
   babl_base_type_float ();
   babl_base_type_u8 ();
@@ -65,7 +66,9 @@ types (void)
 static void
 models (void)
 {
+  babl_hmpf_on_name_lookups--;
   babl_base_model_rgb ();
   babl_base_model_gray ();
+  babl_hmpf_on_name_lookups++;
   babl_base_model_ycbcr ();
 }
diff --git a/babl/base/babl-base.h b/babl/base/babl-base.h
index f3bf6cd..588e2f1 100644
--- a/babl/base/babl-base.h
+++ b/babl/base/babl-base.h
@@ -27,6 +27,7 @@ void babl_base_type_half   (void);
 void babl_base_type_float  (void);
 void babl_base_type_u8     (void);
 void babl_base_type_u16    (void);
+void babl_base_type_u15    (void);
 void babl_base_type_u32    (void);
 
 void babl_base_model_pal   (void);
diff --git a/babl/base/model-gray.c b/babl/base/model-gray.c
index 057c831..239333e 100644
--- a/babl/base/model-gray.c
+++ b/babl/base/model-gray.c
@@ -625,6 +625,43 @@ formats (void)
     babl_type_from_id (BABL_HALF),
     babl_component_from_id (BABL_LUMA),
     NULL);
+  /***********/
+
+  babl_format_new (
+    babl_model_from_id (BABL_GRAY_ALPHA),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_LUMINANCE),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+  babl_format_new (
+    babl_model_from_id (BABL_GRAY_ALPHA_PREMULTIPLIED),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_LUMINANCE_MUL_ALPHA),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+  babl_format_new (
+    babl_model_from_id (BABL_GRAY),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_LUMINANCE),
+    NULL);
+  babl_format_new (
+    babl_model_from_id (BABL_GRAY_GAMMA_2_2_ALPHA),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_LUMA),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+  babl_format_new (
+    babl_model_from_id (BABL_GRAY_GAMMA_2_2_ALPHA_PREMULTIPLIED),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_LUMA_MUL_ALPHA),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+  babl_format_new (
+    babl_model_from_id (BABL_GRAY_GAMMA_2_2),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_LUMA),
+    NULL);
+
   babl_format_new (
     babl_model_from_id (BABL_GRAY_ALPHA),
     babl_type_from_id (BABL_U32),
diff --git a/babl/base/model-rgb.c b/babl/base/model-rgb.c
index 2d72343..4ba6f7d 100644
--- a/babl/base/model-rgb.c
+++ b/babl/base/model-rgb.c
@@ -570,6 +570,59 @@ formats (void)
     babl_component_from_id (BABL_ALPHA),
     NULL);
 
+  /******/
+  babl_format_new (
+    babl_model_from_id (BABL_RGB),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_RED),
+    babl_component_from_id (BABL_GREEN),
+    babl_component_from_id (BABL_BLUE),
+    NULL);
+
+  babl_format_new (
+    babl_model_from_id (BABL_RGBA),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_RED),
+    babl_component_from_id (BABL_GREEN),
+    babl_component_from_id (BABL_BLUE),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+
+  babl_format_new (
+    babl_model_from_id (BABL_RGBA_PREMULTIPLIED),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_RED_MUL_ALPHA),
+    babl_component_from_id (BABL_GREEN_MUL_ALPHA),
+    babl_component_from_id (BABL_BLUE_MUL_ALPHA),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+
+  babl_format_new (
+    babl_model_from_id (BABL_RGB_GAMMA_2_2),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_RED_GAMMA_2_2),
+    babl_component_from_id (BABL_GREEN_GAMMA_2_2),
+    babl_component_from_id (BABL_BLUE_GAMMA_2_2),
+    NULL);
+
+  babl_format_new (
+    babl_model_from_id (BABL_RGBA_GAMMA_2_2),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_RED_GAMMA_2_2),
+    babl_component_from_id (BABL_GREEN_GAMMA_2_2),
+    babl_component_from_id (BABL_BLUE_GAMMA_2_2),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+
+  babl_format_new (
+    babl_model_from_id (BABL_RGBA_GAMMA_2_2_PREMULTIPLIED),
+    babl_type ("u15"),
+    babl_component_from_id (BABL_RED_GAMMA_2_2_MUL_ALPHA),
+    babl_component_from_id (BABL_GREEN_GAMMA_2_2_MUL_ALPHA),
+    babl_component_from_id (BABL_BLUE_GAMMA_2_2_MUL_ALPHA),
+    babl_component_from_id (BABL_ALPHA),
+    NULL);
+
 
   babl_format_new (
     babl_model_from_id (BABL_RGB),
diff --git a/babl/base/type-u15.c b/babl/base/type-u15.c
new file mode 100644
index 0000000..47e3878
--- /dev/null
+++ b/babl/base/type-u15.c
@@ -0,0 +1,136 @@
+/* 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 <string.h>
+#include <stdint.h>
+#include <assert.h>
+#include <math.h>
+
+#include "babl-internal.h"
+#include "babl-base.h"
+
+
+static inline long
+convert_double_u15_scaled (double   min_val,
+                           double   max_val,
+                           uint16_t min,
+                           uint16_t max,
+                           char    *src,
+                           char    *dst,
+                           int      src_pitch,
+                           int      dst_pitch,
+                           long     n)
+{
+  while (n--)
+    {
+      double   dval = *(double *) src;
+      uint16_t u15val;
+
+      if (dval < min_val)
+        u15val = min;
+      else if (dval > max_val)
+        u15val = max;
+      else
+        u15val = rint ((dval - min_val) / (max_val - min_val) * (max - min) + min);
+
+      *(uint16_t *) dst = u15val;
+      dst              += dst_pitch;
+      src              += src_pitch;
+    }
+  return n;
+}
+
+static inline long
+convert_u15_double_scaled (double   min_val,
+                           double   max_val,
+                           uint16_t min,
+                           uint16_t max,
+                           char    *src,
+                           char    *dst,
+                           int      src_pitch,
+                           int      dst_pitch,
+                           long     n)
+{
+  while (n--)
+    {
+      int    u15val = *(uint16_t *) src;
+      double dval;
+
+      if (u15val < min)
+        dval = min_val;
+      else if (u15val > max)
+        dval = max_val;
+      else
+        dval = (u15val - min) / (double) (max - min) * (max_val - min_val) + min_val;
+
+      (*(double *) dst) = dval;
+      dst              += dst_pitch;
+      src              += src_pitch;
+    }
+  return n;
+}
+
+#define MAKE_CONVERSIONS(name, min_val, max_val, min, max)      \
+  static long \
+  convert_ ## name ## _double (void *src, \
+                               void *dst, \
+                               int src_pitch, \
+                               int dst_pitch, \
+                               long n)                               \
+  { \
+    return convert_u15_double_scaled (min_val, max_val, min, max, \
+                                      src, dst, src_pitch, dst_pitch, n); \
+  }                                                               \
+  static long \
+  convert_double_ ## name (void *src, \
+                           void *dst, \
+                           int src_pitch, \
+                           int dst_pitch, \
+                           long n)                                 \
+  { \
+    return convert_double_u15_scaled (min_val, max_val, min, max, \
+                                      src, dst, src_pitch, dst_pitch, n); \
+  }
+
+MAKE_CONVERSIONS (u15, 0.0, 1.0, 0, (1<<15))
+
+void
+babl_base_type_u15 (void)
+{
+  babl_hmpf_on_name_lookups--;
+  babl_type_new (
+    "u15",
+    "bits", 16,
+    NULL);
+
+  babl_conversion_new (
+    babl_type ("u15"),
+    babl_type_from_id (BABL_DOUBLE),
+    "plane", convert_u15_double,
+    NULL
+  );
+
+  babl_conversion_new (
+    babl_type_from_id (BABL_DOUBLE),
+    babl_type ("u15"),
+    "plane", convert_double_u15,
+    NULL
+  );
+  babl_hmpf_on_name_lookups++;
+}