Scanline decoding for bmp

src/codec/SkBmpRLECodec.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.
  */
 
 #include "SkBmpCodec.h"
 #include "SkColorTable.h"
 #include "SkImageInfo.h"
@@ skipping 17 matching lines @@
      * @param numColors the number of colors in the color table
      * @param bytesPerColor the number of bytes in the stream used to represent
                             each color in the color table
      * @param offset the offset of the image pixel data from the end of the
      *               headers
      * @param rowOrder indicates whether rows are ordered top-down or bottom-up
      * @param RLEBytes indicates the amount of data left in the stream
      *                 after decoding the headers
      */
     SkBmpRLECodec(const SkImageInfo& srcInfo, SkStream* stream,
-                  uint16_t bitsPerPixel, uint32_t numColors,
-                  uint32_t bytesPerColor, uint32_t offset,
-                  SkBmpCodec::RowOrder rowOrder, size_t RLEBytes);
+            SkBmpCodec::BmpInputFormat inputFormat, uint16_t bitsPerPixel,
+            uint32_t numColors, uint32_t bytesPerColor, uint32_t offset,
+            SkBmpCodec::RowOrder rowOrder, size_t RLEBytes);
 
 protected:
 
     Result onGetPixels(const SkImageInfo& dstInfo, void* dst,
                        size_t dstRowBytes, const Options&, SkPMColor*,
                        int*) override;
 
 private:
 
     /*
@@ skipping 33 matching lines @@
                   size_t dstRowBytes, const Options& opts);
 
     SkAutoTUnref<SkColorTable>          fColorTable;    // owned
     const uint32_t                      fNumColors;
     const uint32_t                      fBytesPerColor;
     const uint32_t                      fOffset;
     SkAutoTDeleteArray<uint8_t>         fStreamBuffer;
     size_t                              fRLEBytes;
     uint32_t                            fCurrRLEByte;
 
+    friend class SkBmpRLEScanlineDecoder;
+
     typedef SkBmpCodec INHERITED;
 };
+
+/*
+ * Scanline decoder for RLE bmps
+ */
+class SkBmpRLEScanlineDecoder : public SkScanlineDecoder {
+public:
+    SkBmpRLEScanlineDecoder(SkBmpRLECodec* codec);
+
+    SkCodec::Result onStart(const SkImageInfo& dstInfo, const SkCodec::Options& options,
+                            SkPMColor inputColorPtr[], int* inputColorCount) override;
+
+    SkCodec::Result onGetScanlines(void* dst, int count, size_t rowBytes) override;
+
+    // TODO(msarett): Override default skipping with something more clever.
+    // TODO(msarett): Consider other optimizations for this codec.
+
+private:
+    SkAutoTDelete<SkBmpRLECodec>      fCodec;
+    SkImageInfo                       fDstInfo;
+    SkCodec::Options                  fOpts;
+
+    typedef SkScanlineDecoder INHERITED;
+};