xref: /aosp_15_r20/external/skia/src/codec/SkBmpMaskCodec.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2015 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #ifndef SkBmpMaskCodec_DEFINED
9 #define SkBmpMaskCodec_DEFINED
10 
11 #include "include/codec/SkCodec.h"
12 #include "include/core/SkTypes.h"
13 #include "src/codec/SkBmpBaseCodec.h"
14 #include "src/codec/SkMaskSwizzler.h"
15 #include "src/core/SkMasks.h"
16 
17 #include <cstddef>
18 #include <cstdint>
19 #include <memory>
20 
21 class SkSampler;
22 class SkStream;
23 struct SkEncodedInfo;
24 struct SkImageInfo;
25 
26 /*
27  * This class implements the decoding for bmp images using bit masks
28  */
29 class SkBmpMaskCodec : public SkBmpBaseCodec {
30 public:
31 
32     /*
33      * Creates an instance of the decoder
34      *
35      * Called only by SkBmpCodec::MakeFromStream
36      * There should be no other callers despite this being public
37      *
38      * @param info contains properties of the encoded data
39      * @param stream the stream of encoded image data
40      * @param bitsPerPixel the number of bits used to store each pixel
41      * @param masks color masks for certain bmp formats
42      * @param rowOrder indicates whether rows are ordered top-down or bottom-up
43      */
44     SkBmpMaskCodec(SkEncodedInfo&& info, std::unique_ptr<SkStream>,
45             uint16_t bitsPerPixel, SkMasks* masks,
46             SkCodec::SkScanlineOrder rowOrder);
47 
48 protected:
49 
50     Result onGetPixels(const SkImageInfo& dstInfo, void* dst,
51                        size_t dstRowBytes, const Options&,
52                        int*) override;
53 
54     SkCodec::Result onPrepareToDecode(const SkImageInfo& dstInfo,
55             const SkCodec::Options& options) override;
56 
57 private:
58 
getSampler(bool createIfNecessary)59     SkSampler* getSampler(bool createIfNecessary) override {
60         SkASSERT(fMaskSwizzler);
61         return fMaskSwizzler.get();
62     }
63 
64     int decodeRows(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes,
65             const Options& opts) override;
66 
67     std::unique_ptr<SkMasks>        fMasks;
68     std::unique_ptr<SkMaskSwizzler> fMaskSwizzler;
69 
70     using INHERITED = SkBmpBaseCodec;
71 };
72 #endif  // SkBmpMaskCodec_DEFINED
73