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 #include "SkCodec.h"
9 #include "SkData.h"
10 #include "SkCodec_libbmp.h"
11 #include "SkCodec_libgif.h"
12 #include "SkCodec_libico.h"
13 #include "SkCodec_libpng.h"
14 #include "SkCodec_wbmp.h"
15 #include "SkCodecPriv.h"
16 #include "SkJpegCodec.h"
17 #include "SkStream.h"
18
19 struct DecoderProc {
20 bool (*IsFormat)(SkStream*);
21 SkCodec* (*NewFromStream)(SkStream*);
22 };
23
24 static const DecoderProc gDecoderProcs[] = {
25 { SkPngCodec::IsPng, SkPngCodec::NewFromStream },
26 { SkJpegCodec::IsJpeg, SkJpegCodec::NewFromStream },
27 { SkGifCodec::IsGif, SkGifCodec::NewFromStream },
28 { SkIcoCodec::IsIco, SkIcoCodec::NewFromStream },
29 { SkBmpCodec::IsBmp, SkBmpCodec::NewFromStream },
30 { SkWbmpCodec::IsWbmp, SkWbmpCodec::NewFromStream }
31 };
32
NewFromStream(SkStream * stream)33 SkCodec* SkCodec::NewFromStream(SkStream* stream) {
34 if (!stream) {
35 return NULL;
36 }
37
38 SkAutoTDelete<SkStream> streamDeleter(stream);
39
40 SkAutoTDelete<SkCodec> codec(NULL);
41 for (uint32_t i = 0; i < SK_ARRAY_COUNT(gDecoderProcs); i++) {
42 DecoderProc proc = gDecoderProcs[i];
43 const bool correctFormat = proc.IsFormat(stream);
44 if (!stream->rewind()) {
45 return NULL;
46 }
47 if (correctFormat) {
48 codec.reset(proc.NewFromStream(streamDeleter.detach()));
49 break;
50 }
51 }
52
53 // Set the max size at 128 megapixels (512 MB for kN32).
54 // This is about 4x smaller than a test image that takes a few minutes for
55 // dm to decode and draw.
56 const int32_t maxSize = 1 << 27;
57 if (codec && codec->getInfo().width() * codec->getInfo().height() > maxSize) {
58 SkCodecPrintf("Error: Image size too large, cannot decode.\n");
59 return NULL;
60 } else {
61 return codec.detach();
62 }
63 }
64
NewFromData(SkData * data)65 SkCodec* SkCodec::NewFromData(SkData* data) {
66 if (!data) {
67 return NULL;
68 }
69 return NewFromStream(SkNEW_ARGS(SkMemoryStream, (data)));
70 }
71
SkCodec(const SkImageInfo & info,SkStream * stream)72 SkCodec::SkCodec(const SkImageInfo& info, SkStream* stream)
73 : INHERITED(info)
74 , fStream(stream)
75 , fNeedsRewind(false)
76 {}
77
rewindIfNeeded()78 SkCodec::RewindState SkCodec::rewindIfNeeded() {
79 // Store the value of fNeedsRewind so we can update it. Next read will
80 // require a rewind.
81 const bool needsRewind = fNeedsRewind;
82 fNeedsRewind = true;
83 if (!needsRewind) {
84 return kNoRewindNecessary_RewindState;
85 }
86 return fStream->rewind() ? kRewound_RewindState
87 : kCouldNotRewind_RewindState;
88 }
89
getScanlineDecoder(const SkImageInfo & dstInfo,const Options * options,SkPMColor ctable[],int * ctableCount)90 SkScanlineDecoder* SkCodec::getScanlineDecoder(const SkImageInfo& dstInfo, const Options* options,
91 SkPMColor ctable[], int* ctableCount) {
92
93 // Set options.
94 Options optsStorage;
95 if (NULL == options) {
96 options = &optsStorage;
97 }
98
99 fScanlineDecoder.reset(this->onGetScanlineDecoder(dstInfo, *options, ctable, ctableCount));
100 return fScanlineDecoder.get();
101 }
102
getScanlineDecoder(const SkImageInfo & dstInfo)103 SkScanlineDecoder* SkCodec::getScanlineDecoder(const SkImageInfo& dstInfo) {
104 SkASSERT(kIndex_8_SkColorType != dstInfo.colorType());
105 if (kIndex_8_SkColorType == dstInfo.colorType()) {
106 return NULL;
107 }
108 return this->getScanlineDecoder(dstInfo, NULL, NULL, NULL);
109 }
110