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Side by Side Diff: source/libvpx/third_party/libyuv/include/libyuv/mjpeg_decoder.h

Issue 478033002: libvpx: Pull from upstream (Closed) Base URL: svn://svn.chromium.org/chrome/trunk/deps/third_party/libvpx/
Patch Set: Created 6 years, 4 months ago
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1 /*
2 * Copyright 2012 The LibYuv Project Authors. All rights reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #ifndef INCLUDE_LIBYUV_MJPEG_DECODER_H_ // NOLINT
12 #define INCLUDE_LIBYUV_MJPEG_DECODER_H_
13
14 #include "libyuv/basic_types.h"
15
16 #ifdef __cplusplus
17 // NOTE: For a simplified public API use convert.h MJPGToI420().
18
19 struct jpeg_common_struct;
20 struct jpeg_decompress_struct;
21 struct jpeg_source_mgr;
22
23 namespace libyuv {
24
25 #ifdef __cplusplus
26 extern "C" {
27 #endif
28
29 LIBYUV_BOOL ValidateJpeg(const uint8* sample, size_t sample_size);
30
31 #ifdef __cplusplus
32 } // extern "C"
33 #endif
34
35 static const uint32 kUnknownDataSize = 0xFFFFFFFF;
36
37 enum JpegSubsamplingType {
38 kJpegYuv420,
39 kJpegYuv422,
40 kJpegYuv411,
41 kJpegYuv444,
42 kJpegYuv400,
43 kJpegUnknown
44 };
45
46 struct Buffer {
47 const uint8* data;
48 int len;
49 };
50
51 struct BufferVector {
52 Buffer* buffers;
53 int len;
54 int pos;
55 };
56
57 struct SetJmpErrorMgr;
58
59 // MJPEG ("Motion JPEG") is a pseudo-standard video codec where the frames are
60 // simply independent JPEG images with a fixed huffman table (which is omitted).
61 // It is rarely used in video transmission, but is common as a camera capture
62 // format, especially in Logitech devices. This class implements a decoder for
63 // MJPEG frames.
64 //
65 // See http://tools.ietf.org/html/rfc2435
66 class LIBYUV_API MJpegDecoder {
67 public:
68 typedef void (*CallbackFunction)(void* opaque,
69 const uint8* const* data,
70 const int* strides,
71 int rows);
72
73 static const int kColorSpaceUnknown;
74 static const int kColorSpaceGrayscale;
75 static const int kColorSpaceRgb;
76 static const int kColorSpaceYCbCr;
77 static const int kColorSpaceCMYK;
78 static const int kColorSpaceYCCK;
79
80 MJpegDecoder();
81 ~MJpegDecoder();
82
83 // Loads a new frame, reads its headers, and determines the uncompressed
84 // image format.
85 // Returns LIBYUV_TRUE if image looks valid and format is supported.
86 // If return value is LIBYUV_TRUE, then the values for all the following
87 // getters are populated.
88 // src_len is the size of the compressed mjpeg frame in bytes.
89 LIBYUV_BOOL LoadFrame(const uint8* src, size_t src_len);
90
91 // Returns width of the last loaded frame in pixels.
92 int GetWidth();
93
94 // Returns height of the last loaded frame in pixels.
95 int GetHeight();
96
97 // Returns format of the last loaded frame. The return value is one of the
98 // kColorSpace* constants.
99 int GetColorSpace();
100
101 // Number of color components in the color space.
102 int GetNumComponents();
103
104 // Sample factors of the n-th component.
105 int GetHorizSampFactor(int component);
106
107 int GetVertSampFactor(int component);
108
109 int GetHorizSubSampFactor(int component);
110
111 int GetVertSubSampFactor(int component);
112
113 // Public for testability.
114 int GetImageScanlinesPerImcuRow();
115
116 // Public for testability.
117 int GetComponentScanlinesPerImcuRow(int component);
118
119 // Width of a component in bytes.
120 int GetComponentWidth(int component);
121
122 // Height of a component.
123 int GetComponentHeight(int component);
124
125 // Width of a component in bytes with padding for DCTSIZE. Public for testing.
126 int GetComponentStride(int component);
127
128 // Size of a component in bytes.
129 int GetComponentSize(int component);
130
131 // Call this after LoadFrame() if you decide you don't want to decode it
132 // after all.
133 LIBYUV_BOOL UnloadFrame();
134
135 // Decodes the entire image into a one-buffer-per-color-component format.
136 // dst_width must match exactly. dst_height must be <= to image height; if
137 // less, the image is cropped. "planes" must have size equal to at least
138 // GetNumComponents() and they must point to non-overlapping buffers of size
139 // at least GetComponentSize(i). The pointers in planes are incremented
140 // to point to after the end of the written data.
141 // TODO(fbarchard): Add dst_x, dst_y to allow specific rect to be decoded.
142 LIBYUV_BOOL DecodeToBuffers(uint8** planes, int dst_width, int dst_height);
143
144 // Decodes the entire image and passes the data via repeated calls to a
145 // callback function. Each call will get the data for a whole number of
146 // image scanlines.
147 // TODO(fbarchard): Add dst_x, dst_y to allow specific rect to be decoded.
148 LIBYUV_BOOL DecodeToCallback(CallbackFunction fn, void* opaque,
149 int dst_width, int dst_height);
150
151 // The helper function which recognizes the jpeg sub-sampling type.
152 static JpegSubsamplingType JpegSubsamplingTypeHelper(
153 int* subsample_x, int* subsample_y, int number_of_components);
154
155 private:
156
157 void AllocOutputBuffers(int num_outbufs);
158 void DestroyOutputBuffers();
159
160 LIBYUV_BOOL StartDecode();
161 LIBYUV_BOOL FinishDecode();
162
163 void SetScanlinePointers(uint8** data);
164 LIBYUV_BOOL DecodeImcuRow();
165
166 int GetComponentScanlinePadding(int component);
167
168 // A buffer holding the input data for a frame.
169 Buffer buf_;
170 BufferVector buf_vec_;
171
172 jpeg_decompress_struct* decompress_struct_;
173 jpeg_source_mgr* source_mgr_;
174 SetJmpErrorMgr* error_mgr_;
175
176 // LIBYUV_TRUE iff at least one component has scanline padding. (i.e.,
177 // GetComponentScanlinePadding() != 0.)
178 LIBYUV_BOOL has_scanline_padding_;
179
180 // Temporaries used to point to scanline outputs.
181 int num_outbufs_; // Outermost size of all arrays below.
182 uint8*** scanlines_;
183 int* scanlines_sizes_;
184 // Temporary buffer used for decoding when we can't decode directly to the
185 // output buffers. Large enough for just one iMCU row.
186 uint8** databuf_;
187 int* databuf_strides_;
188 };
189
190 } // namespace libyuv
191
192 #endif // __cplusplus
193 #endif // INCLUDE_LIBYUV_MJPEG_DECODER_H_ NOLINT
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