blob: 0cd6634bce97d0e7c079075950ed82a3ef73b246 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkPngChunkReader_DEFINED
#define SkPngChunkReader_DEFINED
#include "SkTypes.h"
#include "SkRefCnt.h"
/**
* SkPngChunkReader
*
* Base class for optional callbacks to retrieve meta/chunk data out of a PNG
* encoded image as it is being decoded.
* Used by SkCodec.
*/
class SkPngChunkReader : public SkRefCnt {
public:
/**
* This will be called by the decoder when it sees an unknown chunk.
*
* Use by SkCodec:
* Depending on the location of the unknown chunks, this callback may be
* called by
* - the factory (NewFromStream/NewFromData)
* - getPixels
* - startScanlineDecode
* - the first call to getScanlines/skipScanlines
* The callback may be called from a different thread (e.g. if the SkCodec
* is passed to another thread), and it may be called multiple times, if
* the SkCodec is used multiple times.
*
* @param tag Name for this type of chunk.
* @param data Data to be interpreted by the subclass.
* @param length Number of bytes of data in the chunk.
* @return true to continue decoding, or false to indicate an error, which
* will cause the decoder to not return the image.
*/
virtual bool readChunk(const char tag[], const void* data, size_t length) = 0;
};
#endif // SkPngChunkReader_DEFINED
|
