Parse ICC profiles from webps

src/codec/SkWebpCodec.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCodecPriv.h"
 #include "SkWebpCodec.h"
 #include "SkTemplates.h"
 
 // A WebP decoder on top of (subset of) libwebp
 // For more information on WebP image format, and libwebp library, see:
 //   https://code.google.com/speed/webp/
 //   http://www.webmproject.org/code/#libwebp-webp-image-library
 //   https://chromium.googlesource.com/webm/libwebp
 
 // If moving libwebp out of skia source tree, path for webp headers must be
 // updated accordingly. Here, we enforce using local copy in webp sub-directory.
 #include "webp/decode.h"
+#include "webp/demux.h"
 #include "webp/encode.h"
 
 bool SkWebpCodec::IsWebp(const void* buf, size_t bytesRead) {
     // WEBP starts with the following:
     // RIFFXXXXWEBPVP
     // Where XXXX is unspecified.
     const char* bytes = static_cast<const char*>(buf);
     return bytesRead >= 14 && !memcmp(bytes, "RIFF", 4) && !memcmp(&bytes[8], "WEBPVP", 6);
 }
 
@@ skipping 59 matching lines @@
             break;
         case 2:
             // This is the lossless format (BGRA).
             color = SkEncodedInfo::kBGRA_Color;
             alpha = SkEncodedInfo::kUnpremul_Alpha;
             break;
         default:
             return nullptr;
     }
 
+    // FIXME (msarett):
+    // Temporary strategy for getting ICC profiles from webps.  Once the incremental decoding
+    // API lands, we will use the WebPDemuxer to manage the entire decode.
+    sk_sp<SkColorSpace> colorSpace = nullptr;
+    const void* memory = stream->getMemoryBase();
+    if (memory) {
+        WebPData data = { (const uint8_t*) memory, stream->getLength() };
+        WebPDemuxState state;
+        WebPDemuxer* demux = WebPDemuxPartial(&data, &state);

[mtklein, 2016/08/24 12:56:50]

Might want to see what this all looks like using an SkAutoTCallVProc or two?

[msarett, 2016/08/24 13:14:24]

Done.

+        WebPChunkIterator chunkIterator;
+        if (WebPDemuxGetChunk(demux, "ICCP", 1, &chunkIterator)) {
+            const void* profileData = chunkIterator.chunk.bytes;
+            size_t profileSize = chunkIterator.chunk.size;
+            colorSpace = SkColorSpace::NewICC(profileData, profileSize);

[mtklein, 2016/08/24 12:56:50]

I might just skip some of the intermediate names here:

 colorspace = SkColorSpace::NewICC(chunkIterator.chunk.bytes,
chunkIterator.chunk.size);

[msarett, 2016/08/24 13:14:24]

Done.

+        }
+        WebPDemuxReleaseChunkIterator(&chunkIterator);
+        WebPDemuxDelete(demux);
+    }
+
+    if (!colorSpace) {
+        colorSpace = SkColorSpace::NewNamed(SkColorSpace::kSRGB_Named);
+    }
+
     SkEncodedInfo info = SkEncodedInfo::Make(color, alpha, 8);
-    return new SkWebpCodec(features.width, features.height, info, streamDeleter.release());
+    return new SkWebpCodec(features.width, features.height, info, colorSpace,
+                           streamDeleter.release());
 }
 
 // This version is slightly different from SkCodecPriv's version of conversion_possible. It
 // supports both byte orders for 8888.
 static bool webp_conversion_possible(const SkImageInfo& dst, const SkImageInfo& src) {
-    // FIXME: skbug.com/4895
-    // Currently, we ignore the SkColorProfileType on the SkImageInfo.  We
-    // will treat the encoded data as linear regardless of what the client
-    // requests.
-
     if (!valid_alpha(dst.alphaType(), src.alphaType())) {
         return false;
     }
 
     switch (dst.colorType()) {
         // Both byte orders are supported.
         case kBGRA_8888_SkColorType:
         case kRGBA_8888_SkColorType:
             return true;
         case kRGB_565_SkColorType:
@@ skipping 142 matching lines @@
                 return kSuccess;
             case VP8_STATUS_SUSPENDED:
                 // Break out of the switch statement. Continue the loop.
                 break;
             default:
                 return kInvalidInput;
         }
     }
 }
 
-SkWebpCodec::SkWebpCodec(int width, int height, const SkEncodedInfo& info, SkStream* stream)
-    // The spec says an unmarked image is sRGB, so we return that space here.
-    // TODO: Add support for parsing ICC profiles from webps.
-    : INHERITED(width, height, info, stream, SkColorSpace::NewNamed(SkColorSpace::kSRGB_Named)) {}
+SkWebpCodec::SkWebpCodec(int width, int height, const SkEncodedInfo& info,
+                         sk_sp<SkColorSpace> colorSpace, SkStream* stream)
+    : INHERITED(width, height, info, stream, colorSpace)
+{}