Added LAB mode, core dumped

PIL/Image.py

@@ -200,6 +200,7 @@ _MODEINFO = {
     "RGBA": ("RGB", "L", ("R", "G", "B", "A")),
     "CMYK": ("RGB", "L", ("C", "M", "Y", "K")),
     "YCbCr": ("RGB", "L", ("Y", "Cb", "Cr")),
+    "LAB": ("RGB", "L", ("L", "A", "B")),
 
     # Experimental modes include I;16, I;16L, I;16B, RGBa, BGR;15, and
     # BGR;24.  Use these modes only if you know exactly what you're
@@ -224,6 +225,7 @@ _MODE_CONV = {
     "RGBA": ('|u1', 4),
     "CMYK": ('|u1', 4),
     "YCbCr": ('|u1', 3),
+    "LAB": ('|u1', 3),
     "I;16": ('=u2', None),
     "I;16B": ('>u2', None),
     "I;16L": ('<u2', None),

Tests/test_imagecms.py

@@ -97,11 +97,11 @@ def test_lab_color_profile():
     
 def test_lab_color():
     pLab = ImageCms.createProfile("LAB")    
-    t = ImageCms.buildTransform(SRGB, pLab, "RGB", "RGB")
+    t = ImageCms.buildTransform(SRGB, pLab, "RGB", "LAB")
     # need to add a type mapping for some PIL type to TYPE_Lab_8 in findLCMSType,
     # and have that mapping work back to a PIL mode. (likely RGB)
     i = ImageCms.applyTransform(lena(), t)
-    assert_image(i, "RGB", (128, 128))
+    assert_image(i, "LAB", (128, 128))
 
     target = Image.open('Tests/images/lena.Lab.tif')
 

_imagingcms.c

@@ -236,6 +236,9 @@ findLCMStype(char* PILmode)
     else if (strcmp(PILmode, "YCC") == 0) {
         return TYPE_YCbCr_8;
     }
+    else if (strcmp(PILmode, "LAB") == 0) {
+        return TYPE_Lab_8;
+    }
 
     else {
         /* take a wild guess... but you probably should fail instead. */

libImaging/Imaging.h

@@ -40,6 +40,7 @@ extern "C" {
  * RGBA	    4		R, G, B, A
  * CMYK	    4		C, M, Y, K
  * YCbCr    4		Y, Cb, Cr, -
+ * Lab      4       L, a, b, -
  *
  * experimental modes (incomplete):
  * LA       4           L, -, -, A

libImaging/Pack.c

@@ -526,6 +526,12 @@ static struct {
     {"YCbCr",  	"Cb",           8,      band1},
     {"YCbCr",  	"Cr",           8,      band2},
 
+    /* LAB Color */
+    {"LAB",	    "LAB",	     24,	ImagingPackRGB},
+    {"LAB",  	"L",            8,      band0},
+    {"LAB",  	"B",           8,      band1},
+    {"LAB",  	"B",           8,      band2},
+
     /* integer */
     {"I", 	"I",		32,	copy4},
     {"I", 	"I;16B",	16,	packI16B},

libImaging/Storage.c

@@ -178,6 +178,12 @@ ImagingNewPrologueSubtype(const char *mode, unsigned xsize, unsigned ysize,
         im->pixelsize = 4;
         im->linesize = xsize * 4;
 
+    } else if (strcmp(mode, "LAB") == 0) {
+        /* 24-bit color, luminance, + 2 color channels */
+        im->bands = 3;
+        im->pixelsize = 4;
+        im->linesize = xsize * 4;
+
     } else {
         free(im);
         return (Imaging) ImagingError_ValueError("unrecognized mode");