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);
+            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;
 
+    SkCodec::Result prepareToDecode(const SkImageInfo& dstInfo,
+            const SkCodec::Options& options, SkPMColor inputColorPtr[],
+            int* inputColorCount) override;
+
 private:
 
     /*
      * Creates the color table
      * Sets colorCount to the new color count if it is non-NULL
      */
     bool createColorTable(int* colorCount);
 
     bool initializeStreamBuffer();
 
@@ skipping 12 matching lines @@
     void setPixel(void* dst, size_t dstRowBytes,
                   const SkImageInfo& dstInfo, uint32_t x, uint32_t y,
                   uint8_t index);
     /*
      * Set an RLE24 pixel from R, G, B values
      */
     void setRGBPixel(void* dst, size_t dstRowBytes,
                      const SkImageInfo& dstInfo, uint32_t x, uint32_t y,
                      uint8_t red, uint8_t green, uint8_t blue);
 
-    /*
-     * Performs the bitmap decoding for RLE input format
-     */
-    Result decode(const SkImageInfo& dstInfo, void* dst,
-                  size_t dstRowBytes, const Options& opts);
+    Result decodeRows(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes,
+                      const Options& opts) override;
 
     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;
+    int                                 fSampleX;
 
     typedef SkBmpCodec INHERITED;
 };