Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(119)

Unified Diff: src/codec/SkBmpCodec.h

Issue 1258863008: Split SkBmpCodec into three separate classes (Closed) Base URL: https://skia.googlesource.com/skia.git@master
Patch Set: Created 5 years, 4 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « gyp/codec.gyp ('k') | src/codec/SkBmpCodec.cpp » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: src/codec/SkBmpCodec.h
diff --git a/src/codec/SkBmpCodec.h b/src/codec/SkBmpCodec.h
index 9909945c51047865cdb72c45a77cfea9125bc395..51d03000919977549919543605daeba40d713e5e 100644
--- a/src/codec/SkBmpCodec.h
+++ b/src/codec/SkBmpCodec.h
@@ -4,6 +4,8 @@
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
+#ifndef SkBmpCodec_DEFINED
+#define SkBmpCodec_DEFINED
#include "SkCodec.h"
#include "SkColorTable.h"
@@ -13,19 +15,15 @@
#include "SkSwizzler.h"
#include "SkTypes.h"
-// TODO: rename SkCodec_libbmp files to SkBmpCodec
/*
- *
- * This class implements the decoding for bmp images
- *
+ * This class enables code sharing between its bmp codec subclasses. The
+ * subclasses actually do the work.
*/
class SkBmpCodec : public SkCodec {
public:
/*
- *
* Describes if rows of the input start at the top or bottom of the image
- *
*/
enum RowOrder {
kTopDown_RowOrder,
@@ -33,161 +31,75 @@ public:
};
/*
- *
* Checks the start of the stream to see if the image is a bmp
- *
*/
static bool IsBmp(SkStream*);
/*
- *
* Assumes IsBmp was called and returned true
* Creates a bmp decoder
* Reads enough of the stream to determine the image format
- *
*/
static SkCodec* NewFromStream(SkStream*);
/*
- *
* Creates a bmp decoder for a bmp embedded in ico
* Reads enough of the stream to determine the image format
- *
*/
static SkCodec* NewFromIco(SkStream*);
protected:
- /*
- *
- * Initiates the bmp decode
- *
- */
- Result onGetPixels(const SkImageInfo& dstInfo, void* dst,
- size_t dstRowBytes, const Options&, SkPMColor*,
- int*) override;
+ SkBmpCodec(const SkImageInfo& info, SkStream* stream, uint16_t bitsPerPixel,
+ RowOrder rowOrder);
SkEncodedFormat onGetEncodedFormat() const override { return kBMP_SkEncodedFormat; }
-private:
-
- /*
- *
- * Used to define the input format of the bmp
- *
- */
- enum BitmapInputFormat {
- kStandard_BitmapInputFormat,
- kRLE_BitmapInputFormat,
- kBitMask_BitmapInputFormat,
- kUnknown_BitmapInputFormat
- };
-
- /*
- *
- * Creates the color table
- * Sets colorCount to the new color count if it is non-NULL
- */
- bool createColorTable(SkAlphaType alphaType, int* colorCount);
-
/*
- *
- * Creates a bmp decoder
- * Reads enough of the stream to determine the image format
- *
- */
- static SkCodec* NewFromStream(SkStream*, bool isIco);
-
- /*
- *
* Read enough of the stream to initialize the SkBmpCodec. Returns a bool
* representing success or failure. If it returned true, and codecOut was
* not NULL, it will be set to a new SkBmpCodec.
* Does *not* take ownership of the passed in SkStream.
- *
*/
- static bool ReadHeader(SkStream*, bool isIco, SkCodec** codecOut);
+ static bool ReadHeader(SkStream*, bool inIco, SkCodec** codecOut);
/*
- *
- * Performs the bitmap decoding for bit masks input format
- *
+ * Rewinds the image stream if necessary
*/
- Result decodeMask(const SkImageInfo& dstInfo, void* dst,
- size_t dstRowBytes, const Options& opts);
+ bool handleRewind(bool inIco);
/*
- *
- * Set an RLE pixel using the color table
- *
- */
- void setRLEPixel(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
- *
+ * Get the destination row to start filling from
+ * Used to fill the remainder of the image on incomplete input for bmps
+ * This is tricky since bmps may be kTopDown or kBottomUp. For kTopDown,
+ * we start filling from where we left off, but for kBottomUp we start
+ * filling at the top of the image.
*/
- void setRLE24Pixel(void* dst, size_t dstRowBytes,
- const SkImageInfo& dstInfo, uint32_t x, uint32_t y,
- uint8_t red, uint8_t green, uint8_t blue);
+ void* getDstStartRow(void* dst, size_t dstRowBytes, int32_t y) const;
/*
- *
- * Performs the bitmap decoding for RLE input format
- *
+ * Compute the number of colors in the color table
*/
- Result decodeRLE(const SkImageInfo& dstInfo, void* dst,
- size_t dstRowBytes, const Options& opts);
+ uint32_t computeNumColors(uint32_t numColors);
/*
- *
- * Performs the bitmap decoding for standard input format
- *
+ * Accessors used by subclasses
*/
- Result decode(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes, const Options& opts);
+ uint16_t bitsPerPixel() const { return fBitsPerPixel; }
+ RowOrder rowOrder() const { return fRowOrder; }
+
+private:
/*
- *
- * Creates an instance of the decoder
- * Called only by NewFromStream
- *
- * @param srcInfo contains the source width and height
- * @param stream the stream of image data
- * @param bitsPerPixel the number of bits used to store each pixel
- * @param format the format of the bmp file
- * @param masks optional color masks for certain bmp formats, passes
- ownership to SkBmpCodec
- * @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 used only for RLE decodes, as we must decode all
- * of the data at once rather than row by row
- * it indicates the amount of data left in the stream
- * after decoding the headers
- *
+ * Creates a bmp decoder
+ * Reads enough of the stream to determine the image format
*/
- SkBmpCodec(const SkImageInfo& srcInfo, SkStream* stream,
- uint16_t bitsPerPixel, BitmapInputFormat format,
- SkMasks* masks, uint32_t numColors, uint32_t bytesPerColor,
- uint32_t offset, RowOrder rowOrder, size_t RLEBytes,
- bool isIco);
-
- // Fields
- const uint16_t fBitsPerPixel;
- const BitmapInputFormat fInputFormat;
- SkAutoTDelete<SkMasks> fMasks; // owned
- SkAutoTUnref<SkColorTable> fColorTable; // owned
- uint32_t fNumColors;
- const uint32_t fBytesPerColor;
- const uint32_t fOffset;
- const RowOrder fRowOrder;
- const size_t fRLEBytes;
- const bool fIsIco;
+ static SkCodec* NewFromStream(SkStream*, bool inIco);
+
+ const uint16_t fBitsPerPixel;
+ const RowOrder fRowOrder;
typedef SkCodec INHERITED;
};
+
+#endif
« no previous file with comments | « gyp/codec.gyp ('k') | src/codec/SkBmpCodec.cpp » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698