Merge remote-tracking branch 'origin/released'

14 files changed, 476 insertions, 19 deletions

diff --git a/pixman/.gitignore b/pixman/.gitignore
index b9853b117..a4d9f99a7 100644
--- a/pixman/.gitignore
+++ b/pixman/.gitignore
@@ -36,12 +36,14 @@ demos/gradient-test
 demos/quad2quad
 demos/radial-test
 demos/screen-test
+demos/srgb-test
 demos/trap-test
 demos/tri-test
 pixman/pixman-combine32.c
 pixman/pixman-combine32.h
 pixman/pixman-combine64.c
 pixman/pixman-combine64.h
+pixman/pixman-srgb.c
 pixman/pixman-version.h
 test/a1-trap-test
 test/affine-test
diff --git a/pixman/demos/Makefile.am b/pixman/demos/Makefile.am
index 9aac1f5e9..d8fb0dab2 100644
--- a/pixman/demos/Makefile.am
+++ b/pixman/demos/Makefile.am
@@ -20,7 +20,8 @@ DEMOS =				\
 	trap-test		\
 	tri-test		\
 	quad2quad		\
-	checkerboard
+	checkerboard		\
+	srgb-test
 
 EXTRA_DIST = parrot.c parrot.jpg
 
@@ -35,6 +36,7 @@ convolution_test_SOURCES = convolution-test.c $(GTK_UTILS)
 radial_test_SOURCES = radial-test.c $(GTK_UTILS)
 tri_test_SOURCES = tri-test.c $(GTK_UTILS)
 checkerboard_SOURCES = checkerboard.c $(GTK_UTILS)
+srgb_test_SOURCES = srgb-test.c $(GTK_UTILS)
 
 noinst_PROGRAMS = $(DEMOS)
 
diff --git a/pixman/demos/srgb-test.c b/pixman/demos/srgb-test.c
new file mode 100644
index 000000000..bc073491e
--- /dev/null
+++ b/pixman/demos/srgb-test.c
@@ -0,0 +1,96 @@
+#include <math.h>
+
+#include "pixman.h"
+#include "gtk-utils.h"
+
+static uint32_t
+linear_argb_to_premult_argb (float a,
+			     float r,
+			     float g,
+			     float b)
+{
+    r *= a;
+    g *= a;
+    b *= a;
+    return (uint32_t) (a * 255.0f + 0.5f) << 24
+	 | (uint32_t) (r * 255.0f + 0.5f) << 16
+	 | (uint32_t) (g * 255.0f + 0.5f) <<  8
+	 | (uint32_t) (b * 255.0f + 0.5f) <<  0;
+}
+
+static float
+lin2srgb (float linear)
+{
+    if (linear < 0.0031308f)
+	return linear * 12.92f;
+    else
+	return 1.055f * powf (linear, 1.0f/2.4f) - 0.055f;
+}
+
+static uint32_t
+linear_argb_to_premult_srgb_argb (float a,
+				  float r,
+				  float g,
+				  float b)
+{
+    r = lin2srgb (r * a);
+    g = lin2srgb (g * a);
+    b = lin2srgb (b * a);
+    return (uint32_t) (a * 255.0f + 0.5f) << 24
+	 | (uint32_t) (r * 255.0f + 0.5f) << 16
+	 | (uint32_t) (g * 255.0f + 0.5f) <<  8
+	 | (uint32_t) (b * 255.0f + 0.5f) <<  0;
+}
+
+int
+main (int argc, char **argv)
+{
+#define WIDTH 400
+#define HEIGHT 200
+    int y, x, p;
+    float alpha;
+ 
+    uint32_t *dest = malloc (WIDTH * HEIGHT * 4);
+    uint32_t *src1 = malloc (WIDTH * HEIGHT * 4);
+    pixman_image_t *dest_img, *src1_img;
+   
+    dest_img = pixman_image_create_bits (PIXMAN_a8r8g8b8_sRGB,
+					 WIDTH, HEIGHT,
+					 dest,
+					 WIDTH * 4);
+    src1_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
+					 WIDTH, HEIGHT,
+					 src1,
+					 WIDTH * 4);
+
+    for (y = 0; y < HEIGHT; y ++)
+    {
+	p = WIDTH * y;
+	for (x = 0; x < WIDTH; x ++)
+	{
+	     alpha = (float) x / WIDTH;
+	     src1[p + x] = linear_argb_to_premult_argb (alpha, 1, 0, 1);
+	     dest[p + x] = linear_argb_to_premult_srgb_argb (1-alpha, 0, 1, 0);
+	}
+    }
+    
+    pixman_image_composite (PIXMAN_OP_ADD, src1_img, NULL, dest_img,
+			    0, 0, 0, 0, 0, 0, WIDTH, HEIGHT);
+    pixman_image_unref (src1_img);
+    free (src1);
+
+    pixman_image_unref (dest_img);
+
+    /* Now that the picture has been correctly constructed,
+     * we hand it over to our support library as argb which it
+     * knows how to handle (it doesn't understand _sRGB format). */
+    dest_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
+			 		 WIDTH, HEIGHT,
+					 dest,
+					 WIDTH * 4);
+    show_image (dest_img);
+    pixman_image_unref (dest_img);
+    free (dest);
+    
+    return 0;
+}
diff --git a/pixman/pixman/Makefile.sources b/pixman/pixman/Makefile.sources
index 6472994c4..cf7040f33 100644
--- a/pixman/pixman/Makefile.sources
+++ b/pixman/pixman/Makefile.sources
@@ -25,6 +25,7 @@ libpixman_sources =			\
 	pixman-region16.c		\
 	pixman-region32.c		\
 	pixman-solid-fill.c		\
+	pixman-srgb.c			\
 	pixman-timer.c			\
 	pixman-trap.c			\
 	pixman-utils.c			\
@@ -46,8 +47,12 @@ BUILT_SOURCES =				\
 	pixman-combine32.h		\
 	pixman-combine64.c		\
 	pixman-combine64.h		\
+	pixman-srgb.c			\
 	$(NULL)
 
+pixman-srgb.c: make-srgb.pl
+	$(PERL) $< > $@ || ($(RM) $@; exit 1)
+
 pixman-combine32.c: pixman-combine.c.template make-combine.pl
 	$(PERL) $(lastword $+) 8 < $< > $@ || ($(RM) $@; exit 1)
 pixman-combine32.h: pixman-combine.h.template make-combine.pl
diff --git a/pixman/pixman/make-srgb.pl b/pixman/pixman/make-srgb.pl
new file mode 100644
index 000000000..ebde2eac6
--- /dev/null
+++ b/pixman/pixman/make-srgb.pl
@@ -0,0 +1,112 @@
+#!/usr/bin/perl -w
+
+use strict;
+
+sub linear_to_srgb
+{
+    my ($c) = @_;
+
+    if ($c < 0.0031308)
+    {
+	return $c * 12.92;
+    }
+    else
+    {
+	return 1.055 * $c ** (1.0/2.4) - 0.055;
+    }
+}
+
+sub srgb_to_linear
+{
+    my ($c) = @_;
+
+    if ($c < 0.04045)
+    {
+	return $c / 12.92;
+    }
+    else
+    {
+	return (($c + 0.055) / 1.055) ** 2.4
+    }
+}
+
+my @linear_to_srgb;
+for my $linear (0 .. 4095)
+{
+    my $srgb = int(linear_to_srgb($linear / 4095.0) * 255.0 + 0.5);
+    push @linear_to_srgb, $srgb;
+}
+
+my @srgb_to_linear;
+for my $srgb (0 .. 255)
+{
+    my $linear = int(srgb_to_linear($srgb / 255.0) * 65535.0 + 0.5);
+    push @srgb_to_linear, $linear;
+}
+
+# Ensure that we have a lossless sRGB and back conversion loop.
+# some of the darkest shades need a little bias -- maximum is just
+# 5 increments out of 16. This gives us useful property with
+# least amount of error in the sRGB-to-linear table, and keeps the actual
+# table lookup in the other direction as simple as possible.
+for my $srgb (0 .. $#srgb_to_linear)
+{
+    my $add = 0;
+    while (1)
+    {
+	my $linear = $srgb_to_linear[$srgb];
+	my $srgb_lossy = $linear_to_srgb[$linear >> 4];
+	last if $srgb == $srgb_lossy;
+
+	# Add slight bias to this component until it rounds correctly
+	$srgb_to_linear[$srgb] ++;
+	$add ++;
+    }
+    die "Too many adds at $srgb" if $add > 5;
+}
+
+print <<"PROLOG";
+/* WARNING: This file is generated by $0.
+ * Please edit that file instead of this one.
+ */
+
+#include <stdint.h>
+
+#include "config.h"
+#include "pixman-private.h"
+
+PROLOG
+
+print "const uint8_t linear_to_srgb[" . @linear_to_srgb . "] =\n";
+print "{\n";
+for my $linear (0 .. $#linear_to_srgb)
+{
+    if (($linear % 10) == 0)
+    {
+	print "\t";
+    }
+    print sprintf("%d, ", $linear_to_srgb[$linear]);
+    if (($linear % 10) == 9)
+    {
+	print "\n";
+    }
+}
+print "\n};\n";
+print "\n";
+
+print "const uint16_t srgb_to_linear[" . @srgb_to_linear . "] =\n";
+print "{\n";
+for my $srgb (0 .. $#srgb_to_linear)
+{
+    if (($srgb % 10) == 0)
+    {
+	print "\t";
+    }
+    print sprintf("%d, ", $srgb_to_linear[$srgb]);
+    if (($srgb % 10) == 9)
+    {
+	print "\n";
+    }
+}
+print "\n};\n";
+
diff --git a/pixman/pixman/pixman-access.c b/pixman/pixman/pixman-access.c
index 6743887d0..9feafc49d 100644
--- a/pixman/pixman/pixman-access.c
+++ b/pixman/pixman/pixman-access.c
@@ -32,8 +32,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "pixman-private.h"
 #include "pixman-accessor.h"
+#include "pixman-private.h"
 
 #define CONVERT_RGB24_TO_Y15(s)						\
     (((((s) >> 16) & 0xff) * 153 +					\
@@ -210,6 +210,7 @@ get_shifts (pixman_format_code_t  format,
 	break;
 
     case PIXMAN_TYPE_ARGB:
+    case PIXMAN_TYPE_ARGB_SRGB:
 	*b = 0;
 	*g = *b + PIXMAN_FORMAT_B (format);
 	*r = *g + PIXMAN_FORMAT_G (format);
@@ -1027,6 +1028,130 @@ fetch_pixel_generic_64 (bits_image_t *image,
     return result;
 }
 
+/* The 32_sRGB paths should be deleted after narrow processing
+ * is no longer invoked for formats that are considered wide.
+ * (Also see fetch_pixel_generic_lossy_32) */
+static void
+fetch_scanline_a8r8g8b8_32_sRGB (pixman_image_t *image,
+                                 int             x,
+                                 int             y,
+                                 int             width,
+                                 uint32_t       *buffer,
+                                 const uint32_t *mask)
+{
+    const uint32_t *bits = image->bits.bits + y * image->bits.rowstride;
+    const uint32_t *pixel = (uint32_t *)bits + x;
+    const uint32_t *end = pixel + width;
+    uint32_t tmp;
+    
+    while (pixel < end)
+    {
+	tmp = READ (image, pixel++);
+	*buffer++ =                 (tmp >> 24)               << 24
+		  | (srgb_to_linear[(tmp >> 16) & 0xff] >> 8) << 16
+		  | (srgb_to_linear[(tmp >>  8) & 0xff] >> 8) <<  8
+		  | (srgb_to_linear[(tmp >>  0) & 0xff] >> 8) <<  0;
+    }
+}
+
+static void
+fetch_scanline_a8r8g8b8_64_sRGB (pixman_image_t *image,
+                                 int             x,
+                                 int             y,
+                                 int             width,
+                                 uint32_t       *b,
+                                 const uint32_t *mask)
+{
+    const uint32_t *bits = image->bits.bits + y * image->bits.rowstride;
+    const uint32_t *pixel = (uint32_t *)bits + x;
+    const uint32_t *end = pixel + width;
+    uint64_t *buffer = (uint64_t *)b;
+    uint32_t tmp;
+    
+    while (pixel < end)
+    {
+	tmp = READ (image, pixel++);
+	*buffer++ = (uint64_t)               ((tmp >> 24) * 257)  << 48
+		  | (uint64_t) srgb_to_linear[(tmp >> 16) & 0xff] << 32
+		  | (uint64_t) srgb_to_linear[(tmp >>  8) & 0xff] << 16
+		  | (uint64_t) srgb_to_linear[(tmp >>  0) & 0xff] <<  0;
+    }
+}
+
+static uint32_t
+fetch_pixel_a8r8g8b8_32_sRGB (bits_image_t *image,
+			      int           offset,
+			      int           line)
+{
+    uint32_t *bits = image->bits + line * image->rowstride;
+    uint32_t tmp = READ (image, bits + offset);
+    return                 (tmp >> 24)               << 24
+	 | (srgb_to_linear[(tmp >> 16) & 0xff] >> 8) << 16
+	 | (srgb_to_linear[(tmp >>  8) & 0xff] >> 8) <<  8
+	 | (srgb_to_linear[(tmp >>  0) & 0xff] >> 8) <<  0;
+}
+
+static uint64_t
+fetch_pixel_a8r8g8b8_64_sRGB (bits_image_t *image,
+			      int           offset,
+			      int	    line)
+{
+    uint32_t *bits = image->bits + line * image->rowstride;
+    uint32_t tmp = READ (image, bits + offset);
+    return (uint64_t)               ((tmp >> 24) * 257)  << 48
+	 | (uint64_t) srgb_to_linear[(tmp >> 16) & 0xff] << 32
+	 | (uint64_t) srgb_to_linear[(tmp >>  8) & 0xff] << 16
+	 | (uint64_t) srgb_to_linear[(tmp >>  0) & 0xff] <<  0;
+}
+
+static void
+store_scanline_a8r8g8b8_32_sRGB (bits_image_t   *image,
+                                 int             x,
+                                 int             y,
+                                 int             width,
+                                 const uint32_t *v)
+{
+    uint32_t *bits = image->bits + image->rowstride * y;
+    uint64_t *values = (uint64_t *)v;
+    uint32_t *pixel = bits + x;
+    uint64_t tmp;
+    int i;
+    
+    for (i = 0; i < width; ++i)
+    {
+	tmp = values[i];
+	WRITE (image, pixel++,
+		  ((uint32_t)     (tmp >> 24     )          << 24)
+		| (linear_to_srgb[(tmp >> 16 << 4) & 0xfff] << 16)
+		| (linear_to_srgb[(tmp >>  8 << 4) & 0xfff] <<  8)
+		| (linear_to_srgb[(tmp >>  0 << 4) & 0xfff] <<  0));
+    }
+}
+
+static void
+store_scanline_a8r8g8b8_64_sRGB (bits_image_t  *image,
+                                int             x,
+                                int             y,
+                                int             width,
+                                const uint32_t *v)
+{
+    uint32_t *bits = image->bits + image->rowstride * y;
+    uint64_t *values = (uint64_t *)v;
+    uint32_t *pixel = bits + x;
+    uint64_t tmp;
+    int i;
+    
+    for (i = 0; i < width; ++i)
+    {
+	tmp = values[i];
+	WRITE (image, pixel++,
+		  ((uint32_t)     (tmp >> 56)          << 24)
+		| (linear_to_srgb[(tmp >> 36) & 0xfff] << 16)
+		| (linear_to_srgb[(tmp >> 20) & 0xfff] <<  8)
+		| (linear_to_srgb[(tmp >>  4) & 0xfff] <<  0));
+    }
+}
+
 /*
  * XXX: The transformed fetch path only works at 32-bpp so far.  When all
  * paths have wide versions, this can be removed.
@@ -1079,6 +1204,13 @@ static const format_info_t accessors[] =
     FORMAT_INFO (r8g8b8x8),
     FORMAT_INFO (x14r6g6b6),
 
+/* sRGB formats */
+  { PIXMAN_a8r8g8b8_sRGB,
+    fetch_scanline_a8r8g8b8_32_sRGB,
+    fetch_scanline_a8r8g8b8_64_sRGB,
+    fetch_pixel_a8r8g8b8_32_sRGB, fetch_pixel_a8r8g8b8_64_sRGB,
+    store_scanline_a8r8g8b8_32_sRGB, store_scanline_a8r8g8b8_64_sRGB },
+
 /* 24bpp formats */
     FORMAT_INFO (r8g8b8),
     FORMAT_INFO (b8g8r8),
diff --git a/pixman/pixman/pixman-image.c b/pixman/pixman/pixman-image.c
index 8b634a7dc..15597bd61 100644
--- a/pixman/pixman/pixman-image.c
+++ b/pixman/pixman/pixman-image.c
@@ -909,7 +909,8 @@ _pixman_image_get_solid (pixman_implementation_t *imp,
     }
 
     /* If necessary, convert RGB <--> BGR. */
-    if (PIXMAN_FORMAT_TYPE (format) != PIXMAN_TYPE_ARGB)
+    if (PIXMAN_FORMAT_TYPE (format) != PIXMAN_TYPE_ARGB
+	&& PIXMAN_FORMAT_TYPE (format) != PIXMAN_TYPE_ARGB_SRGB)
     {
 	result = (((result & 0xff000000) >>  0) |
 	          ((result & 0x00ff0000) >> 16) |
diff --git a/pixman/pixman/pixman-private.h b/pixman/pixman/pixman-private.h
index 4d8f64d3b..d5e6a72ee 100644
--- a/pixman/pixman/pixman-private.h
+++ b/pixman/pixman/pixman-private.h
@@ -887,7 +887,8 @@ pixman_list_move_to_front (pixman_list_t *list, pixman_link_t *link)
     (PIXMAN_FORMAT_A (f) > 8 ||						\
      PIXMAN_FORMAT_R (f) > 8 ||						\
      PIXMAN_FORMAT_G (f) > 8 ||						\
-     PIXMAN_FORMAT_B (f) > 8)
+     PIXMAN_FORMAT_B (f) > 8 ||						\
+     PIXMAN_FORMAT_TYPE (f) == PIXMAN_TYPE_ARGB_SRGB)
 
 #ifdef WORDS_BIGENDIAN
 #   define SCREEN_SHIFT_LEFT(x,n)	((x) << (n))
@@ -1083,6 +1084,18 @@ void pixman_timer_register (pixman_timer_t *timer);
 
 #endif /* PIXMAN_TIMERS */
 
+/* sRGB<->linear conversion tables. Linear color space is the same
+ * as sRGB but the components are in linear light (gamma 1.0).
+ *
+ * linear_to_srgb maps linear value from 0 to 4095 ([0.0, 1.0])
+ * and returns 8-bit sRGB value.
+ *
+ * srgb_to_linear maps 8-bit sRGB value to 16-bit linear value
+ * with range 0 to 65535 ([0.0, 1.0]).
+ */
+extern const uint8_t linear_to_srgb[4096];
+extern const uint16_t srgb_to_linear[256];
+
 #endif /* __ASSEMBLER__ */
 
 #endif /* PIXMAN_PRIVATE_H */
diff --git a/pixman/pixman/pixman.c b/pixman/pixman/pixman.c
index 0137c3cab..994ef388c 100644
--- a/pixman/pixman/pixman.c
+++ b/pixman/pixman/pixman.c
@@ -1017,6 +1017,7 @@ pixman_format_supported_source (pixman_format_code_t format)
     case PIXMAN_a2r10g10b10:
     case PIXMAN_x2r10g10b10:
     case PIXMAN_a8r8g8b8:
+    case PIXMAN_a8r8g8b8_sRGB:
     case PIXMAN_x8r8g8b8:
     case PIXMAN_a8b8g8r8:
     case PIXMAN_x8b8g8r8:
diff --git a/pixman/pixman/pixman.h b/pixman/pixman/pixman.h
index 7233ceb8a..e1cb90a7d 100644
--- a/pixman/pixman/pixman.h
+++ b/pixman/pixman/pixman.h
@@ -653,6 +653,7 @@ struct pixman_indexed
 #define PIXMAN_TYPE_YV12	7
 #define PIXMAN_TYPE_BGRA	8
 #define PIXMAN_TYPE_RGBA	9
+#define PIXMAN_TYPE_ARGB_SRGB	10
 
 #define PIXMAN_FORMAT_COLOR(f)				\
 	(PIXMAN_FORMAT_TYPE(f) == PIXMAN_TYPE_ARGB ||	\
@@ -676,6 +677,9 @@ typedef enum {
     PIXMAN_x2b10g10r10 = PIXMAN_FORMAT(32,PIXMAN_TYPE_ABGR,0,10,10,10),
     PIXMAN_a2b10g10r10 = PIXMAN_FORMAT(32,PIXMAN_TYPE_ABGR,2,10,10,10),
 
+/* sRGB formats */
+    PIXMAN_a8r8g8b8_sRGB = PIXMAN_FORMAT(32,PIXMAN_TYPE_ARGB_SRGB,8,8,8,8),
+
 /* 24bpp formats */
     PIXMAN_r8g8b8 =	 PIXMAN_FORMAT(24,PIXMAN_TYPE_ARGB,0,8,8,8),
     PIXMAN_b8g8r8 =	 PIXMAN_FORMAT(24,PIXMAN_TYPE_ABGR,0,8,8,8),
diff --git a/pixman/test/composite.c b/pixman/test/composite.c
index bdecd75a7..2930fb75b 100644
--- a/pixman/test/composite.c
+++ b/pixman/test/composite.c
@@ -99,6 +99,9 @@ static const format_t formats[] =
     P(x2b10g10r10),
     P(a2r10g10b10),
     P(a2b10g10r10),
+    
+    /* sRGB formats */
+    P(a8r8g8b8_sRGB),
 
     /* 24 bpp formats */
     P(r8g8b8),
@@ -524,17 +527,8 @@ composite_test (image_t *dst,
 		pixman_bool_t component_alpha,
 		int testno)
 {
-    pixman_color_t fill;
     color_t expected, tdst, tsrc, tmsk;
     pixel_checker_t checker;
-    pixman_image_t *solid;
-
-    /* Initialize dst */
-    compute_pixman_color (dst->color, &fill);
-    solid = pixman_image_create_solid_fill (&fill);
-    pixman_image_composite32 (PIXMAN_OP_SRC, solid, NULL, dst->image,
-			      0, 0, 0, 0, 0, 0, dst->size, dst->size);
-    pixman_image_unref (solid);
 
     if (mask)
     {
@@ -553,17 +547,56 @@ composite_test (image_t *dst,
     }
 
     tdst = *dst->color;
-    round_color (dst->format->format, &tdst);
-
     tsrc = *src->color;
-    if (src->size)
-	round_color (src->format->format, &tsrc);
 
     if (mask)
     {
 	tmsk = *mask->color;
-	if (mask->size)
+    }
+
+    /* It turns out that by construction all source, mask etc. colors are
+     * linear because they are made from fills, and fills are always in linear
+     * color space.  However, if they have been converted to bitmaps, we need
+     * to simulate the sRGB approximation to pass the test cases.
+     */
+    if (src->size)
+    {
+	if (PIXMAN_FORMAT_TYPE (src->format->format) == PIXMAN_TYPE_ARGB_SRGB)
+        {
+	    tsrc.r = convert_linear_to_srgb (tsrc.r);
+	    tsrc.g = convert_linear_to_srgb (tsrc.g);
+	    tsrc.b = convert_linear_to_srgb (tsrc.b);
+	    round_color (src->format->format, &tsrc);
+	    tsrc.r = convert_srgb_to_linear (tsrc.r);
+	    tsrc.g = convert_srgb_to_linear (tsrc.g);
+	    tsrc.b = convert_srgb_to_linear (tsrc.b);
+	}
+        else
+        {
+	    round_color (src->format->format, &tsrc);
+	}
+    }
+
+    if (mask && mask->size)
+    {
+	if (PIXMAN_FORMAT_TYPE (mask->format->format) == PIXMAN_TYPE_ARGB_SRGB)
+	{
+	    tmsk.r = convert_linear_to_srgb (tmsk.r);
+	    tmsk.g = convert_linear_to_srgb (tmsk.g);
+	    tmsk.b = convert_linear_to_srgb (tmsk.b);
 	    round_color (mask->format->format, &tmsk);
+	    tmsk.r = convert_srgb_to_linear (tmsk.r);
+	    tmsk.g = convert_srgb_to_linear (tmsk.g);
+	    tmsk.b = convert_srgb_to_linear (tmsk.b);
+	}
+	else
+	{
+	    round_color (mask->format->format, &tmsk);
+	}
+    }
+
+    if (mask)
+    {
 	if (component_alpha && PIXMAN_FORMAT_R (mask->format->format) == 0)
 	{
 	    /* Ax component-alpha masks expand alpha into
@@ -573,6 +606,21 @@ composite_test (image_t *dst,
 	}
     }
 
+    if (PIXMAN_FORMAT_TYPE (dst->format->format) == PIXMAN_TYPE_ARGB_SRGB)
+    {
+	tdst.r = convert_linear_to_srgb (tdst.r);
+	tdst.g = convert_linear_to_srgb (tdst.g);
+	tdst.b = convert_linear_to_srgb (tdst.b);
+    	round_color (dst->format->format, &tdst);
+	tdst.r = convert_srgb_to_linear (tdst.r);
+	tdst.g = convert_srgb_to_linear (tdst.g);
+	tdst.b = convert_srgb_to_linear (tdst.b);
+    }
+    else
+    {
+    	round_color (dst->format->format, &tdst);
+    }
+
     do_composite (op->op,
 		  &tsrc,
 		  mask? &tmsk : NULL,
diff --git a/pixman/test/stress-test.c b/pixman/test/stress-test.c
index 9280802bd..54ab1c5a9 100644
--- a/pixman/test/stress-test.c
+++ b/pixman/test/stress-test.c
@@ -25,6 +25,7 @@ static const pixman_format_code_t image_formats[] =
     PIXMAN_x14r6g6b6,
     PIXMAN_r8g8b8,
     PIXMAN_b8g8r8,
+    PIXMAN_a8r8g8b8_sRGB,
     PIXMAN_r5g6b5,
     PIXMAN_b5g6r5,
     PIXMAN_x2r10g10b10,
diff --git a/pixman/test/utils.c b/pixman/test/utils.c
index 563b33d52..85b58d038 100644
--- a/pixman/test/utils.c
+++ b/pixman/test/utils.c
@@ -1,6 +1,7 @@
 #define _GNU_SOURCE
 
 #include "utils.h"
+#include <math.h>
 #include <signal.h>
 #include <stdlib.h>
 
@@ -765,6 +766,24 @@ aligned_malloc (size_t align, size_t size)
        (((c) >>  8) & 0xff) * 301 +					\
        (((c)      ) & 0xff) * 58) >> 2))
 
+double
+convert_srgb_to_linear (double c)
+{
+    if (c <= 0.04045)
+        return c / 12.92;
+    else
+        return powf ((c + 0.055) / 1.055, 2.4);
+}
+
+double
+convert_linear_to_srgb (double c)
+{
+    if (c <= 0.0031308)
+        return c * 12.92;
+    else
+        return 1.055 * powf (c, 1.0/2.4) - 0.055;
+}
+
 void
 initialize_palette (pixman_indexed_t *palette, uint32_t depth, int is_rgb)
 {
@@ -868,6 +887,7 @@ pixel_checker_init (pixel_checker_t *checker, pixman_format_code_t format)
 	break;
 
     case PIXMAN_TYPE_ARGB:
+    case PIXMAN_TYPE_ARGB_SRGB:
 	checker->bs = 0;
 	checker->gs = checker->bs + PIXMAN_FORMAT_B (format);
 	checker->rs = checker->gs + PIXMAN_FORMAT_G (format);
@@ -968,11 +988,25 @@ pixel_checker_get_min (const pixel_checker_t *checker, color_t *color,
 
 pixman_bool_t
 pixel_checker_check (const pixel_checker_t *checker, uint32_t pixel,
-		     color_t *color)
+		     color_t *color_in)
 {
     int32_t a_lo, a_hi, r_lo, r_hi, g_lo, g_hi, b_lo, b_hi;
     int32_t ai, ri, gi, bi;
     pixman_bool_t result;
+    color_t tmp, *color;
+
+    if (PIXMAN_FORMAT_TYPE (checker->format) == PIXMAN_TYPE_ARGB_SRGB)
+    {
+	tmp.a = color_in->a;
+	tmp.r = convert_linear_to_srgb (color_in->r);
+	tmp.g = convert_linear_to_srgb (color_in->g);
+	tmp.b = convert_linear_to_srgb (color_in->b);
+	color = &tmp;
+    }
+    else
+    {
+	color = color_in;
+    }
 
     pixel_checker_get_min (checker, color, &a_lo, &r_lo, &g_lo, &b_lo);
     pixel_checker_get_max (checker, color, &a_hi, &r_hi, &g_hi, &b_hi);
diff --git a/pixman/test/utils.h b/pixman/test/utils.h
index ac2decd11..faf427f0a 100644
--- a/pixman/test/utils.h
+++ b/pixman/test/utils.h
@@ -163,6 +163,12 @@ write_png (pixman_image_t *image, const char *filename);
 void *
 aligned_malloc (size_t align, size_t size);
 
+double
+convert_srgb_to_linear (double component);
+
+double
+convert_linear_to_srgb (double component);
+
 void
 initialize_palette (pixman_indexed_t *palette, uint32_t depth, int is_rgb);