Add SkCodec, including PNG implementation.

dm/DMSrcSink.cpp

 #include "DMSrcSink.h"
 #include "SamplePipeControllers.h"
 #include "SkCommonFlags.h"
+#include "SkCodec.h"
 #include "SkDocument.h"
 #include "SkMultiPictureDraw.h"
 #include "SkNullCanvas.h"
 #include "SkOSFile.h"
 #include "SkPictureRecorder.h"
 #include "SkRandom.h"
 #include "SkSVGCanvas.h"
 #include "SkStream.h"
 #include "SkXMLWriter.h"
 
+DEFINE_bool(codec, false, "Use SkCodec instead of SkImageDecoder");
+
 namespace DM {
 
 GMSrc::GMSrc(skiagm::GMRegistry::Factory factory) : fFactory(factory) {}
 
 Error GMSrc::draw(SkCanvas* canvas) const {
     SkAutoTDelete<skiagm::GM> gm(fFactory(NULL));
     canvas->concat(gm->getInitialTransform());
     gm->draw(canvas);
     return "";
 }
@@ skipping 14 matching lines @@
 
 Error ImageSrc::draw(SkCanvas* canvas) const {
     SkAutoTUnref<SkData> encoded(SkData::NewFromFileName(fPath.c_str()));
     if (!encoded) {
         return SkStringPrintf("Couldn't read %s.", fPath.c_str());
     }
     const SkColorType dstColorType = canvas->imageInfo().colorType();
     if (fDivisor == 0) {
         // Decode the full image.
         SkBitmap bitmap;
-        if (!SkImageDecoder::DecodeMemory(encoded->data(), encoded->size(), &bitmap,
-                                          dstColorType, SkImageDecoder::kDecodePixels_Mode)) {
-            return SkStringPrintf("Couldn't decode %s.", fPath.c_str());
+        if (FLAGS_codec) {
+            SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(encoded));

[mtklein, 2015/02/26 20:41:13]

You might want to split off a CodecSrc as a separate src type from ImageSrc,
enabled by something like --config codec-8888.  That way you can run both the
old and the new paths in the same run (for local testing, for the bots,
whatever).

[scroggo, 2015/02/26 21:00:11]

Thanks for the feedback. This is really a stopgap measure, allowing me/Matt to
run locally. I want to expand the image testing to test various aspects of
SkCodec. See skbug.com/3475 for more info.

+            if (!codec) {
+                return SkStringPrintf("Couldn't decode %s.", fPath.c_str());
+            }
+            SkImageInfo info;
+            if (!codec->getInfo(&info)) {
+                return SkStringPrintf("Couldn't getInfo %s.", fPath.c_str());
+            }
+            info = info.makeColorType(dstColorType);
+            if (info.alphaType() == kUnpremul_SkAlphaType) {
+                // FIXME: Currently we cannot draw unpremultiplied sources.
+                info = info.makeAlphaType(kPremul_SkAlphaType);
+            }
+            if (!bitmap.tryAllocPixels(info)) {
+                return SkStringPrintf("Image(%s) is too large (%d x %d)\n", fPath.c_str(),
+                                      info.width(), info.height());
+            }
+            SkAutoLockPixels alp(bitmap);
+            const SkImageGenerator::Result result = codec->getPixels(info, bitmap.getPixels(),
+                                                                     bitmap.rowBytes());
+            if (result != SkImageGenerator::kSuccess) {
+                return SkStringPrintf("Couldn't getPixels %s.", fPath.c_str());
+            }
+        } else {
+            if (!SkImageDecoder::DecodeMemory(encoded->data(), encoded->size(), &bitmap,
+                                              dstColorType, SkImageDecoder::kDecodePixels_Mode)) {
+                return SkStringPrintf("Couldn't decode %s.", fPath.c_str());
+            }
         }
         encoded.reset((SkData*)NULL);  // Might as well drop this when we're done with it.
         canvas->drawBitmap(bitmap, 0,0);
         return "";
     }
     // Decode subsets.  This is a little involved.
     SkAutoTDelete<SkMemoryStream> stream(new SkMemoryStream(encoded));
     SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(stream.get()));
     if (!decoder) {
         return SkStringPrintf("Can't find a good decoder for %s.", fPath.c_str());
@@ skipping 396 matching lines @@
             surfaces.unrefAll();
             return "";
         }
         SkISize size() const SK_OVERRIDE { return fSize; }
         Name name() const SK_OVERRIDE { sk_throw(); return ""; }  // No one should be calling this.
     } proxy(fW, fH, pic, src.size());
     return fSink->draw(proxy, bitmap, stream, log);
 }
 
 }  // namespace DM