Parse icc profiles and exif orientation from jpeg markers

include/codec/SkCodec.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkCodec_DEFINED
 #define SkCodec_DEFINED
 
@@ skipping 89 matching lines @@
      */
     const SkImageInfo& getInfo() const { return fSrcInfo; }
 
     /**
      *  Returns the color space associated with the codec.
      *  Does not affect ownership.
      *  Might be NULL.
      */
     SkColorSpace* getColorSpace() const { return fColorSpace.get(); }
 
+    enum Orientation {
+        kOriginTopLeft_Orientation     = 1, // Default
+        kOriginTopRight_Orientation    = 2, // Reflected across y-axis
+        kOriginBottomRight_Orientation = 3, // Rotated 180
+        kOriginBottomLeft_Orientation  = 4, // Reflected across x-axis
+        kOriginLeftTop_Orientation     = 5, // Reflected across x-axis, Rotated 90 CCW
+        kOriginRightTop_Orientation    = 6, // Rotated 90 CW
+        kOriginRightBottom_Orientation = 7, // Reflected across x-axis, Rotated 90 CW
+        kOriginLeftBottom_Orientation  = 8, // Rotated 90 CCW
+        kDefault_Orientation           = kOriginTopLeft_Orientation,
+        kLast_Orientation              = kOriginLeftBottom_Orientation,
+    };
+
+    /**
+     *  Returns the image orientation stored in the EXIF data.
+     *  If there is no EXIF data, or if we cannot read the EXIF data, returns kOriginTopLeft.
+     */
+    Orientation getOrientation() const { return fOrientation; }
+
     /**
      *  Return a size that approximately supports the desired scale factor.
      *  The codec may not be able to scale efficiently to the exact scale
      *  factor requested, so return a size that approximates that scale.
      *  The returned value is the codec's suggestion for the closest valid
      *  scale that it can natively support
      */
     SkISize getScaledDimensions(float desiredScale) const {
         // Negative and zero scales are errors.
         SkASSERT(desiredScale > 0.0f);
@@ skipping 364 matching lines @@
      *  is located in the encoded data.
      *
      *  This will equal inputScanline, except in the case of strangely
      *  encoded image types (bottom-up bmps, interlaced gifs).
      */
     int outputScanline(int inputScanline) const;
 
 protected:
     /**
      *  Takes ownership of SkStream*
      *  Does not affect ownership of SkColorSpace*

[scroggo, 2016/03/18 22:38:17]

This comment can be removed, I think.

[msarett, 2016/03/21 14:28:45]

Done.

      */
-    SkCodec(const SkImageInfo&, SkStream*, sk_sp<SkColorSpace> = nullptr);
+    SkCodec(const SkImageInfo&,
+            SkStream*,
+            sk_sp<SkColorSpace> = nullptr,
+            Orientation = kOriginTopLeft_Orientation);
 
     virtual SkISize onGetScaledDimensions(float /*desiredScale*/) const {
         // By default, scaling is not supported.
         return this->getInfo().dimensions();
     }
 
     // FIXME: What to do about subsets??
     /**
      *  Subclasses should override if they support dimensions other than the
      *  srcInfo's.
@@ skipping 111 matching lines @@
      */
     int currScanline() const { return fCurrScanline; }
 
     virtual int onOutputScanline(int inputScanline) const;
 
 private:
     const SkImageInfo           fSrcInfo;
     SkAutoTDelete<SkStream>     fStream;
     bool                        fNeedsRewind;
     sk_sp<SkColorSpace>         fColorSpace;
+    Orientation                 fOrientation;

[scroggo, 2016/03/18 22:38:17]

Can this be const?

[msarett, 2016/03/21 14:28:45]

Yes!  Done.

 
     // These fields are only meaningful during scanline decodes.
     SkImageInfo                 fDstInfo;
     SkCodec::Options            fOptions;
     int                         fCurrScanline;
 
     /**
      *  Return whether these dimensions are supported as a scale.
      *
      *  The codec may choose to cache the information about scale and subset.
@@ skipping 40 matching lines @@
      *  not affect ownership.
      *
      *  Only valid during scanline decoding.
      */
     virtual SkSampler* getSampler(bool /*createIfNecessary*/) { return nullptr; }
 
     friend class SkSampledCodec;
     friend class SkIcoCodec;
 };
 #endif // SkCodec_DEFINED