1 /*
2 * MxPEG decoder
3 * Copyright (c) 2011 Anatoly Nenashev
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22
23 /**
24 * @file
25 * MxPEG decoder
26 */
27
28 #include "codec_internal.h"
29 #include "internal.h"
30 #include "mjpeg.h"
31 #include "mjpegdec.h"
32
33 typedef struct MXpegDecodeContext {
34 MJpegDecodeContext jpg;
35 AVFrame *picture[2]; /* pictures array */
36 int picture_index; /* index of current picture */
37 int got_sof_data; /* true if SOF data successfully parsed */
38 int got_mxm_bitmask; /* true if MXM bitmask available */
39 uint8_t *mxm_bitmask; /* bitmask buffer */
40 unsigned bitmask_size; /* size of bitmask */
41 int has_complete_frame; /* true if has complete frame */
42 uint8_t *completion_bitmask; /* completion bitmask of macroblocks */
43 unsigned mb_width, mb_height; /* size of picture in MB's from MXM header */
44 } MXpegDecodeContext;
45
mxpeg_decode_end(AVCodecContext *avctx)46 static av_cold int mxpeg_decode_end(AVCodecContext *avctx)
47 {
48 MXpegDecodeContext *s = avctx->priv_data;
49 MJpegDecodeContext *jpg = &s->jpg;
50 int i;
51
52 jpg->picture_ptr = NULL;
53 ff_mjpeg_decode_end(avctx);
54
55 for (i = 0; i < 2; ++i)
56 av_frame_free(&s->picture[i]);
57
58 s->bitmask_size = 0;
59 av_freep(&s->mxm_bitmask);
60 av_freep(&s->completion_bitmask);
61
62 return 0;
63 }
64
mxpeg_decode_init(AVCodecContext *avctx)65 static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
66 {
67 MXpegDecodeContext *s = avctx->priv_data;
68
69 s->picture[0] = av_frame_alloc();
70 s->picture[1] = av_frame_alloc();
71 if (!s->picture[0] || !s->picture[1])
72 return AVERROR(ENOMEM);
73
74 s->jpg.picture_ptr = s->picture[0];
75 return ff_mjpeg_decode_init(avctx);
76 }
77
mxpeg_decode_app(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)78 static int mxpeg_decode_app(MXpegDecodeContext *s,
79 const uint8_t *buf_ptr, int buf_size)
80 {
81 int len;
82 if (buf_size < 2)
83 return 0;
84 len = AV_RB16(buf_ptr);
85 skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
86
87 return 0;
88 }
89
mxpeg_decode_mxm(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)90 static int mxpeg_decode_mxm(MXpegDecodeContext *s,
91 const uint8_t *buf_ptr, int buf_size)
92 {
93 unsigned bitmask_size, mb_count;
94 int i;
95
96 s->mb_width = AV_RL16(buf_ptr+4);
97 s->mb_height = AV_RL16(buf_ptr+6);
98 mb_count = s->mb_width * s->mb_height;
99
100 bitmask_size = (mb_count + 7) >> 3;
101 if (bitmask_size > buf_size - 12) {
102 av_log(s->jpg.avctx, AV_LOG_ERROR,
103 "MXM bitmask is not complete\n");
104 return AVERROR(EINVAL);
105 }
106
107 if (s->bitmask_size != bitmask_size) {
108 s->bitmask_size = 0;
109 av_freep(&s->mxm_bitmask);
110 s->mxm_bitmask = av_malloc(bitmask_size);
111 if (!s->mxm_bitmask) {
112 av_log(s->jpg.avctx, AV_LOG_ERROR,
113 "MXM bitmask memory allocation error\n");
114 return AVERROR(ENOMEM);
115 }
116
117 av_freep(&s->completion_bitmask);
118 s->completion_bitmask = av_mallocz(bitmask_size);
119 if (!s->completion_bitmask) {
120 av_log(s->jpg.avctx, AV_LOG_ERROR,
121 "Completion bitmask memory allocation error\n");
122 return AVERROR(ENOMEM);
123 }
124
125 s->bitmask_size = bitmask_size;
126 }
127
128 memcpy(s->mxm_bitmask, buf_ptr + 12, bitmask_size);
129 s->got_mxm_bitmask = 1;
130
131 if (!s->has_complete_frame) {
132 uint8_t completion_check = 0xFF;
133 for (i = 0; i < bitmask_size; ++i) {
134 s->completion_bitmask[i] |= s->mxm_bitmask[i];
135 completion_check &= s->completion_bitmask[i];
136 }
137 s->has_complete_frame = !(completion_check ^ 0xFF);
138 }
139
140 return 0;
141 }
142
mxpeg_decode_com(MXpegDecodeContext *s, const uint8_t *buf_ptr, int buf_size)143 static int mxpeg_decode_com(MXpegDecodeContext *s,
144 const uint8_t *buf_ptr, int buf_size)
145 {
146 int len, ret = 0;
147 if (buf_size < 2)
148 return 0;
149 len = AV_RB16(buf_ptr);
150 if (len > 14 && len <= buf_size && !strncmp(buf_ptr + 2, "MXM", 3)) {
151 ret = mxpeg_decode_mxm(s, buf_ptr + 2, len - 2);
152 }
153 skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
154
155 return ret;
156 }
157
mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg, AVFrame *reference_ptr)158 static int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg,
159 AVFrame *reference_ptr)
160 {
161 if ((jpg->width + 0x0F)>>4 != s->mb_width ||
162 (jpg->height + 0x0F)>>4 != s->mb_height) {
163 av_log(jpg->avctx, AV_LOG_ERROR,
164 "Picture dimensions stored in SOF and MXM mismatch\n");
165 return AVERROR(EINVAL);
166 }
167
168 if (reference_ptr->data[0]) {
169 int i;
170 for (i = 0; i < MAX_COMPONENTS; ++i) {
171 if ( (!reference_ptr->data[i] ^ !jpg->picture_ptr->data[i]) ||
172 reference_ptr->linesize[i] != jpg->picture_ptr->linesize[i]) {
173 av_log(jpg->avctx, AV_LOG_ERROR,
174 "Dimensions of current and reference picture mismatch\n");
175 return AVERROR(EINVAL);
176 }
177 }
178 }
179
180 return 0;
181 }
182
mxpeg_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)183 static int mxpeg_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
184 int *got_frame, AVPacket *avpkt)
185 {
186 const uint8_t *buf = avpkt->data;
187 int buf_size = avpkt->size;
188 MXpegDecodeContext *s = avctx->priv_data;
189 MJpegDecodeContext *jpg = &s->jpg;
190 const uint8_t *buf_end, *buf_ptr;
191 const uint8_t *unescaped_buf_ptr;
192 int unescaped_buf_size;
193 int start_code;
194 int ret;
195
196 if (avctx->skip_frame == AVDISCARD_ALL)
197 return AVERROR_PATCHWELCOME;
198
199 buf_ptr = buf;
200 buf_end = buf + buf_size;
201 jpg->got_picture = 0;
202 s->got_mxm_bitmask = 0;
203 s->got_sof_data = !!s->got_sof_data;
204 while (buf_ptr < buf_end) {
205 start_code = ff_mjpeg_find_marker(jpg, &buf_ptr, buf_end,
206 &unescaped_buf_ptr, &unescaped_buf_size);
207 if (start_code < 0)
208 goto the_end;
209 {
210 init_get_bits(&jpg->gb, unescaped_buf_ptr, unescaped_buf_size*8);
211
212 if (start_code >= APP0 && start_code <= APP15) {
213 mxpeg_decode_app(s, unescaped_buf_ptr, unescaped_buf_size);
214 }
215
216 switch (start_code) {
217 case SOI:
218 if (jpg->got_picture) //emulating EOI
219 goto the_end;
220 break;
221 case EOI:
222 goto the_end;
223 case DQT:
224 ret = ff_mjpeg_decode_dqt(jpg);
225 if (ret < 0) {
226 av_log(avctx, AV_LOG_ERROR,
227 "quantization table decode error\n");
228 return ret;
229 }
230 break;
231 case DHT:
232 ret = ff_mjpeg_decode_dht(jpg);
233 if (ret < 0) {
234 av_log(avctx, AV_LOG_ERROR,
235 "huffman table decode error\n");
236 return ret;
237 }
238 break;
239 case COM:
240 ret = mxpeg_decode_com(s, unescaped_buf_ptr,
241 unescaped_buf_size);
242 if (ret < 0)
243 return ret;
244 break;
245 case SOF0:
246 if (s->got_sof_data > 1) {
247 av_log(avctx, AV_LOG_ERROR,
248 "Multiple SOF in a frame\n");
249 return AVERROR_INVALIDDATA;
250 }
251 ret = ff_mjpeg_decode_sof(jpg);
252 if (ret < 0) {
253 av_log(avctx, AV_LOG_ERROR,
254 "SOF data decode error\n");
255 s->got_sof_data = 0;
256 return ret;
257 }
258 if (jpg->interlaced) {
259 av_log(avctx, AV_LOG_ERROR,
260 "Interlaced mode not supported in MxPEG\n");
261 s->got_sof_data = 0;
262 return AVERROR(EINVAL);
263 }
264 s->got_sof_data ++;
265 break;
266 case SOS:
267 if (!s->got_sof_data) {
268 av_log(avctx, AV_LOG_WARNING,
269 "Can not process SOS without SOF data, skipping\n");
270 break;
271 }
272 if (!jpg->got_picture) {
273 if (jpg->first_picture) {
274 av_log(avctx, AV_LOG_WARNING,
275 "First picture has no SOF, skipping\n");
276 break;
277 }
278 if (!s->got_mxm_bitmask){
279 av_log(avctx, AV_LOG_WARNING,
280 "Non-key frame has no MXM, skipping\n");
281 break;
282 }
283 /* use stored SOF data to allocate current picture */
284 av_frame_unref(jpg->picture_ptr);
285 if ((ret = ff_get_buffer(avctx, jpg->picture_ptr,
286 AV_GET_BUFFER_FLAG_REF)) < 0)
287 return ret;
288 jpg->picture_ptr->pict_type = AV_PICTURE_TYPE_P;
289 jpg->picture_ptr->key_frame = 0;
290 jpg->got_picture = 1;
291 } else {
292 jpg->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
293 jpg->picture_ptr->key_frame = 1;
294 }
295
296 if (s->got_mxm_bitmask) {
297 AVFrame *reference_ptr = s->picture[s->picture_index ^ 1];
298 if (mxpeg_check_dimensions(s, jpg, reference_ptr) < 0)
299 break;
300
301 /* allocate dummy reference picture if needed */
302 if (!reference_ptr->data[0] &&
303 (ret = ff_get_buffer(avctx, reference_ptr,
304 AV_GET_BUFFER_FLAG_REF)) < 0)
305 return ret;
306
307 ret = ff_mjpeg_decode_sos(jpg, s->mxm_bitmask, s->bitmask_size, reference_ptr);
308 if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
309 return ret;
310 } else {
311 ret = ff_mjpeg_decode_sos(jpg, NULL, 0, NULL);
312 if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
313 return ret;
314 }
315
316 break;
317 }
318
319 buf_ptr += (get_bits_count(&jpg->gb)+7) >> 3;
320 }
321
322 }
323
324 the_end:
325 if (jpg->got_picture) {
326 int ret = av_frame_ref(rframe, jpg->picture_ptr);
327 if (ret < 0)
328 return ret;
329 *got_frame = 1;
330
331 s->picture_index ^= 1;
332 jpg->picture_ptr = s->picture[s->picture_index];
333
334 if (!s->has_complete_frame) {
335 if (!s->got_mxm_bitmask)
336 s->has_complete_frame = 1;
337 else
338 *got_frame = 0;
339 }
340 }
341
342 return buf_ptr - buf;
343 }
344
345 const FFCodec ff_mxpeg_decoder = {
346 .p.name = "mxpeg",
347 .p.long_name = NULL_IF_CONFIG_SMALL("Mobotix MxPEG video"),
348 .p.type = AVMEDIA_TYPE_VIDEO,
349 .p.id = AV_CODEC_ID_MXPEG,
350 .priv_data_size = sizeof(MXpegDecodeContext),
351 .init = mxpeg_decode_init,
352 .close = mxpeg_decode_end,
353 FF_CODEC_DECODE_CB(mxpeg_decode_frame),
354 .p.capabilities = AV_CODEC_CAP_DR1,
355 .p.max_lowres = 3,
356 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
357 };
358