Allow decoding without color conversion - part 2

Bug: b/135133301

Follow-on to 196f319b.

- Add SkCodec::getICCProfile to match the SkAndroidCodec version.
- Update comments on getPixels() regarding how the SkColorSpace on the
SkImageInfo is treated.
- Add two new images that have ICC profiles that do not map to an
SkColorSpace. Add a test to verify that they have the un-transformed
color we expect.
- Stop uploading ColorCodecSrc images decoded to a null SkColorSpace to
Gold. Though they may be correct, they do not match other images they're
compared against. The new test above verifies that we do not do color
conversion with a null SkColorSpace.

Change-Id: I08635e4262f16500fab32ef97511d305c2c06483
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/269236
Reviewed-by: Derek Sollenberger <djsollen@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>

RELEASE_NOTES.txt

@@ -23,8 +23,8 @@ Milestone 82
     Use CTFontManagerCreateFontDescriptorFromData instead of
     CGFontCreateWithDataProvider to create CTFonts to avoid memory use issues.
 
-  * Added SkAndroidCodec::getICCProfile for reporting the native ICC profile of
-    an encoded image, even if it doesn't map to an SkColorSpace.
+  * Added SkCodec:: and SkAndroidCodec::getICCProfile for reporting the native
+    ICC profile of an encoded image, even if it doesn't map to an SkColorSpace.
 
 * * *
 

dm/DMSrcSink.cpp

@@ -980,7 +980,16 @@ Error ColorCodecSrc::draw(SkCanvas* canvas) const {
 
     SkImageInfo info = codec->getInfo();
     if (fDecodeToDst) {
-        info = canvas->imageInfo().makeDimensions(info.dimensions());
+        SkImageInfo canvasInfo = canvas->imageInfo();
+        if (!canvasInfo.colorSpace()) {
+            // This will skip color conversion, and the resulting images will
+            // look different from images they are compared against in Gold, but
+            // that doesn't mean they are wrong. We have a test verifying that
+            // passing a null SkColorSpace skips conversion, so skip this
+            // misleading test.
+            return Error::Nonfatal("Skipping decoding without color transform.");
+        }
+        info = canvasInfo.makeDimensions(info.dimensions());
     }
 
     SkBitmap bitmap;

include/codec/SkCodec.h

@@ -190,6 +190,9 @@ public:
 
     /**
      *  Return a reasonable SkImageInfo to decode into.
+     *
+     *  If the image has an ICC profile that does not map to an SkColorSpace,
+     *  the returned SkImageInfo will use SRGB.
      */
     SkImageInfo getInfo() const { return fEncodedInfo.makeImageInfo(); }
 
@@ -198,6 +201,13 @@ public:
         return SkIRect::MakeWH(fEncodedInfo.width(), fEncodedInfo.height());
     }
 
+    /**
+     * Return the ICC profile of the encoded data.
+     */
+    const skcms_ICCProfile* getICCProfile() const {
+        return this->getEncodedInfo().profile();
+    }
+
     /**
      *  Returns the image orientation stored in the EXIF data.
      *  If there is no EXIF data, or if we cannot read the EXIF data, returns kTopLeft.
@@ -344,9 +354,13 @@ public:
      *
      *         If the info contains a non-null SkColorSpace, the codec
      *         will perform the appropriate color space transformation.
-     *         If the caller passes in the same color space that was
-     *         reported by the codec, the color space transformation is
-     *         a no-op.
+     *
+     *         If the caller passes in the SkColorSpace that maps to the
+     *         ICC profile reported by getICCProfile(), the color space
+     *         transformation is a no-op.
+     *
+     *         If the caller passes a null SkColorSpace, no color space
+     *         transformation will be done.
      *
      *  If a scanline decode is in progress, scanline mode will end, requiring the client to call
      *  startScanlineDecode() in order to return to decoding scanlines.

tests/CodecTest.cpp

@@ -1787,3 +1787,47 @@ DEF_TEST(Codec_F16_noColorSpace, r) {
                                        .makeColorSpace(nullptr);
     test_info(r, codec.get(), info, SkCodec::kSuccess, nullptr);
 }
+
+// These test images have ICC profiles that do not map to an SkColorSpace.
+// Verify that decoding them with a null destination space does not perform
+// color space transformations.
+DEF_TEST(Codec_noConversion, r) {
+    const struct Rec {
+        const char* name;
+        SkColor color;
+    } recs[] = {
+      { "images/cmyk_yellow_224_224_32.jpg", 0xFFD8FC04 },
+      { "images/wide_gamut_yellow_224_224_64.jpeg",0xFFE0E040 },
+    };
+
+    for (const auto& rec : recs) {
+        auto data = GetResourceAsData(rec.name);
+        if (!data) {
+            continue;
+        }
+
+        auto codec = SkCodec::MakeFromData(std::move(data));
+        if (!codec) {
+            ERRORF(r, "Failed to create a codec from %s", rec.name);
+            continue;
+        }
+
+        const auto* profile = codec->getICCProfile();
+        if (!profile) {
+            ERRORF(r, "Expected %s to have a profile", rec.name);
+            continue;
+        }
+
+        auto cs = SkColorSpace::Make(*profile);
+        REPORTER_ASSERT(r, !cs.get());
+
+        SkImageInfo info = codec->getInfo().makeColorSpace(nullptr);
+        SkBitmap bm;
+        bm.allocPixels(info);
+        if (codec->getPixels(info, bm.getPixels(), bm.rowBytes()) != SkCodec::kSuccess) {
+            ERRORF(r, "Failed to decode %s", rec.name);
+            continue;
+        }
+        REPORTER_ASSERT(r, bm.getColor(0, 0) == rec.color);
+    }
+}