FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavcodec/mjpegdec.h
Date: 2026-03-13 22:30:28
Exec Total Coverage
Lines: 17 18 94.4%
Functions: 2 2 100.0%
Branches: 9 10 90.0%
Line Branch Exec Source
1 /*
2 * MJPEG decoder
3 * Copyright (c) 2000, 2001 Fabrice Bellard
4 * Copyright (c) 2003 Alex Beregszaszi
5 * Copyright (c) 2003-2004 Michael Niedermayer
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 /**
25 * @file
26 * MJPEG decoder.
27 */
28
29 #ifndef AVCODEC_MJPEGDEC_H
30 #define AVCODEC_MJPEGDEC_H
31
32 #include "libavutil/log.h"
33 #include "libavutil/mem_internal.h"
34 #include "libavutil/pixdesc.h"
35 #include "libavutil/stereo3d.h"
36
37 #include "avcodec.h"
38 #include "blockdsp.h"
39 #include "bytestream.h"
40 #include "exif.h"
41 #include "get_bits.h"
42 #include "hpeldsp.h"
43 #include "idctdsp.h"
44
45 #undef near /* This file uses struct member 'near' which in windows.h is defined as empty. */
46
47 #define MAX_COMPONENTS 4
48
49 typedef struct ICCEntry {
50 uint8_t *data;
51 int length;
52 } ICCEntry;
53
54 struct JLSState;
55
56 typedef struct MJpegDecodeContext {
57 AVClass *class;
58 AVCodecContext *avctx;
59 GetBitContext gb;
60 GetByteContext gB;
61 int buf_size;
62
63 int buffer_size;
64 uint8_t *buffer;
65
66 uint16_t quant_matrixes[4][64];
67 VLC vlcs[3][4];
68 int qscale[4]; ///< quantizer scale calculated from quant_matrixes
69
70 int orig_height; /* size given at codec init */
71 int first_picture; /* true if decoding first picture */
72 int interlaced; /* true if interlaced */
73 int bottom_field; /* true if bottom field */
74 int lossless;
75 int ls;
76 int progressive;
77 int bayer; /* true if it's a bayer-encoded JPEG embedded in a DNG */
78 int rgb;
79 uint8_t upscale_h[4];
80 uint8_t upscale_v[4];
81 int rct; /* standard rct */
82 int pegasus_rct; /* pegasus reversible colorspace transform */
83 int bits; /* bits per component */
84 int colr;
85 int xfrm;
86 int adobe_transform;
87
88 /* SOS fields */
89 int nb_components_sos;
90 int Ss;
91 int Se;
92 int Ah;
93 int Al;
94
95 int maxval;
96 int near; ///< near lossless bound (si 0 for lossless)
97 int t1,t2,t3;
98 int reset; ///< context halfing interval ?rename
99
100 int width, height;
101 int mb_width, mb_height;
102 int nb_components;
103 int block_stride[MAX_COMPONENTS];
104 int component_id[MAX_COMPONENTS];
105 int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */
106 int v_count[MAX_COMPONENTS];
107 int comp_index[MAX_COMPONENTS];
108 int dc_index[MAX_COMPONENTS];
109 int ac_index[MAX_COMPONENTS];
110 int nb_blocks[MAX_COMPONENTS];
111 int h_scount[MAX_COMPONENTS];
112 int v_scount[MAX_COMPONENTS];
113 int quant_sindex[MAX_COMPONENTS];
114 int h_max, v_max; /* maximum h and v counts */
115 int quant_index[4]; /* quant table index for each component */
116 int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */
117 AVFrame *picture; /* picture structure */
118 AVFrame *picture_ptr; /* pointer to picture structure */
119 int got_picture; ///< we found a SOF and picture is valid, too.
120 int linesize[MAX_COMPONENTS]; ///< linesize << interlaced
121 DECLARE_ALIGNED(32, int16_t, block)[64];
122 int16_t (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode)
123 uint8_t *last_nnz[MAX_COMPONENTS];
124 uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode)
125 int palette_index;
126 int force_pal8;
127 uint8_t permutated_scantable[64];
128 BlockDSPContext bdsp;
129 IDCTDSPContext idsp;
130 op_pixels_func copy_block; ///< only set and used by mxpeg
131
132 int restart_interval;
133 int restart_count;
134
135 int cs_itu601;
136 int interlace_polarity;
137 int multiscope;
138
139 int mjpb_skiptosod;
140
141 int cur_scan; /* current scan, used by JPEG-LS */
142 int flipped; /* true if picture is flipped */
143
144 uint16_t (*ljpeg_buffer)[4];
145 unsigned int ljpeg_buffer_size;
146
147 #if FF_API_MJPEG_EXTERN_HUFF
148 int extern_huff;
149 #endif
150 AVExifMetadata exif_metadata;
151
152 AVStereo3D *stereo3d; ///!< stereoscopic information (cached, since it is read before frame allocation)
153
154 const AVPixFmtDescriptor *pix_desc;
155
156 ICCEntry *iccentries;
157 int iccnum;
158 int iccread;
159
160 AVFrame *smv_frame;
161 int smv_frames_per_jpeg;
162 int smv_next_frame;
163
164 // Raw stream data for hwaccel use.
165 const uint8_t *raw_image_buffer;
166 size_t raw_image_buffer_size;
167
168 uint8_t raw_huffman_lengths[2][4][16];
169 uint8_t raw_huffman_values[2][4][256];
170
171 enum AVPixelFormat hwaccel_sw_pix_fmt;
172 enum AVPixelFormat hwaccel_pix_fmt;
173 void *hwaccel_picture_private;
174 struct JLSState *jls_state;
175
176 const uint8_t *mb_bitmask;
177 size_t mb_bitmask_size;
178 const AVFrame *reference;
179 } MJpegDecodeContext;
180
181 int ff_mjpeg_build_vlc(VLC *vlc, const uint8_t *bits_table,
182 const uint8_t *val_table, int is_ac, void *logctx);
183 int ff_mjpeg_decode_init(AVCodecContext *avctx);
184 int ff_mjpeg_decode_end(AVCodecContext *avctx);
185 int ff_mjpeg_decode_frame(AVCodecContext *avctx,
186 AVFrame *frame, int *got_frame,
187 AVPacket *avpkt);
188 int ff_mjpeg_decode_frame_from_buf(AVCodecContext *avctx,
189 AVFrame *frame, int *got_frame,
190 const AVPacket *avpkt, const uint8_t *buf, int buf_size);
191 int ff_mjpeg_decode_dqt(MJpegDecodeContext *s);
192 int ff_mjpeg_decode_dht(MJpegDecodeContext *s);
193 int ff_mjpeg_decode_sof(MJpegDecodeContext *s);
194 int ff_mjpeg_decode_sos(MJpegDecodeContext *s);
195 int ff_mjpeg_find_marker(const uint8_t **buf_ptr, const uint8_t *buf_end);
196 int ff_mjpeg_unescape_sos(MJpegDecodeContext *s);
197
198 4679677 static inline int ff_mjpeg_should_restart(MJpegDecodeContext *s)
199 {
200 4679677 int restart = 0;
201
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 4679677 if (s->restart_interval) {
202
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 60554 if (s->restart_count <= 0) {
203 3554 s->restart_count = s->restart_interval;
204 3554 restart = 1;
205 }
206 60554 s->restart_count--;
207 } else {
208
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 4619123 if (s->restart_count < 0) {
209 2425 s->restart_count = 0;
210 2425 restart = 1;
211 }
212 }
213 4679677 return restart;
214 }
215
216 4623437 static inline int ff_mjpeg_handle_restart(MJpegDecodeContext *s, int *restart)
217 {
218 4623437 *restart = ff_mjpeg_should_restart(s);
219
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 4623437 if (*restart) {
220 5905 int ret = ff_mjpeg_unescape_sos(s);
221
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 5905 if (ret < 0)
222 ✗ return ret;
223 }
224 4623437 return 0;
225 }
226
227 #endif /* AVCODEC_MJPEGDEC_H */
228