xref: /aosp_15_r20/external/skia/include/codec/SkRawDecoder.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2023 Google LLC
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 #ifndef SkRawDecoder_DEFINED
8 #define SkRawDecoder_DEFINED
9 
10 #include "include/codec/SkCodec.h"
11 #include "include/core/SkRefCnt.h"
12 #include "include/private/base/SkAPI.h"
13 
14 class SkData;
15 class SkStream;
16 
17 #include <memory>
18 
19 namespace SkRawDecoder {
20 
IsRaw(const void *,size_t)21 inline bool IsRaw(const void*, size_t) {
22     // Raw formats are tricky to detect just by reading in the first several bytes.
23     // For example, PIEX might need to read 10k bytes to detect Sony's arw format
24     // https://github.com/google/piex/blob/f1e15dd837c04347504149f71db67a78fbeddc73/src/image_type_recognition/image_type_recognition_lite.cc#L152
25     // Thus, we just assume everything might be a RAW file and check it last.
26     return true;
27 }
28 
29 /**
30  *  Attempts to decode the given bytes as a raw image.
31  *
32  *  If the bytes are not a raw, returns nullptr.
33  *
34  *  DecodeContext is ignored
35  */
36 SK_API std::unique_ptr<SkCodec> Decode(std::unique_ptr<SkStream>,
37                                        SkCodec::Result*,
38                                        SkCodecs::DecodeContext = nullptr);
39 SK_API std::unique_ptr<SkCodec> Decode(sk_sp<SkData>,
40                                        SkCodec::Result*,
41                                        SkCodecs::DecodeContext = nullptr);
42 
43 // This decoder will always be checked last, no matter when it is registered.
Decoder()44 inline constexpr SkCodecs::Decoder Decoder() {
45     return { "raw", IsRaw, Decode };
46 }
47 
48 }  // namespace SkRawDecoder
49 
50 #endif  // SkRawDecoder_DEFINED
51