Added sRGB and cHRM chunks to PngInfo, added tests for #2782

PIL/PngImagePlugin.py

@@ -387,12 +387,31 @@ class PngStream(ChunkStream):
         return s
 
     def chunk_gAMA(self, pos, length):
-
         # gamma setting
         s = ImageFile._safe_read(self.fp, length)
         self.im_info["gamma"] = i32(s) / 100000.0
         return s
 
+    def chunk_cHRM(self, pos, length):
+        # chromaticity, 8 unsigned ints, actual value is scaled by 100000
+        # WP x,y, Red x,y, Green x,y Blue x,y
+
+        s = ImageFile._safe_read(self.fp, length)
+        raw_vals = struct.unpack('>%dI' % (len(s) // 4), s)
+        self.im_info['chromaticity'] = tuple(elt/100000.0 for elt in raw_vals)
+        return s
+
+    def chunk_sRGB(self, pos, length):
+        # srgb rendering intent, 1 byte
+        # 0 perceptual
+        # 1 relative folorimetric
+        # 2 saturation
+        # 3 absolute colorimetric
+
+        s = ImageFile._safe_read(self.fp, length)
+        self.im_info['srgb'] = i8(s)
+        return s
+
     def chunk_pHYs(self, pos, length):
 
         # pixels per unit

Tests/test_file_png.py

@@ -53,8 +53,7 @@ class TestFilePng(PillowTestCase):
         chunks = []
         with open(filename, "rb") as fp:
             fp.read(8)
-            png = PngImagePlugin.PngStream(fp)
-            while True:
+            while PngImagePlugin.PngStream(fp) as png:
                 cid, pos, length = png.read()
                 chunks.append(cid)
                 try:
@@ -516,22 +515,7 @@ class TestFilePng(PillowTestCase):
         test_file = self.tempfile("temp.png")
         im.convert("P").save(test_file, dpi=(100, 100))
 
-<<<<<<< 1cf2deba3bdb3ea93fdd859c0f052dfcea898c52
-        chunks = []
-        with open(test_file, "rb") as fp:
-            fp.read(8)
-            with PngImagePlugin.PngStream(fp) as png:
-                while True:
-                    cid, pos, length = png.read()
-                    chunks.append(cid)
-                    try:
-                        s = png.call(cid, pos, length)
-                    except EOFError:
-                        break
-                    png.crc(cid, s)
-=======
         chunks = self.get_chunks(test_file)
->>>>>>> refactor out get_chunks
 
         # https://www.w3.org/TR/PNG/#5ChunkOrdering
         # IHDR - shall be first