libwebp: update to 0.5.0

third_party/libwebp/enc/picture_tools.c

 // Copyright 2014 Google Inc. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the COPYING file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS. All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
 // WebPPicture tools: alpha handling, etc.
 //
 // Author: Skal (pascal.massimino@gmail.com)
 
+#include <assert.h>
+
 #include "./vp8enci.h"
 #include "../dsp/yuv.h"
 
 static WEBP_INLINE uint32_t MakeARGB32(int r, int g, int b) {
   return (0xff000000u | (r << 16) | (g << 8) | b);
 }
 
 //------------------------------------------------------------------------------
 // Helper: clean up fully transparent area to help compressibility.
 
@@ skipping 89 matching lines @@
           need_reset = 1;
         }
       }
     }
   }
 }
 
 #undef SIZE
 #undef SIZE2
 
+void WebPCleanupTransparentAreaLossless(WebPPicture* const pic) {
+  int x, y, w, h;
+  uint32_t* argb;
+  assert(pic != NULL && pic->use_argb);
+  w = pic->width;
+  h = pic->height;
+  argb = pic->argb;
+
+  for (y = 0; y < h; ++y) {
+    for (x = 0; x < w; ++x) {
+      if ((argb[x] & 0xff000000) == 0) {
+        argb[x] = 0x00000000;
+      }
+    }
+    argb += pic->argb_stride;
+  }
+}
+
 //------------------------------------------------------------------------------
 // Blend color and remove transparency info
 
 #define BLEND(V0, V1, ALPHA) \
     ((((V0) * (255 - (ALPHA)) + (V1) * (ALPHA)) * 0x101) >> 16)
 #define BLEND_10BIT(V0, V1, ALPHA) \
     ((((V0) * (1020 - (ALPHA)) + (V1) * (ALPHA)) * 0x101) >> 18)
 
 void WebPBlendAlpha(WebPPicture* pic, uint32_t background_rgb) {
   const int red = (background_rgb >> 16) & 0xff;
@@ skipping 64 matching lines @@
       }
       argb += pic->argb_stride;
     }
   }
 }
 
 #undef BLEND
 #undef BLEND_10BIT
 
 //------------------------------------------------------------------------------