FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavformat/moflex.c
Date: 2024-04-25 15:36:26
Exec Total Coverage
Lines: 5 221 2.3%
Functions: 1 10 10.0%
Branches: 1 125 0.8%

Line Branch Exec Source
1 /*
2 * MOFLEX demuxer
3 * Copyright (c) 2015-2016 Florian Nouwt
4 * Copyright (c) 2017 Adib Surani
5 * Copyright (c) 2020 Paul B Mahol
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 #include "libavcodec/bytestream.h"
25
26 #include "avformat.h"
27 #include "demux.h"
28 #include "internal.h"
29
30 typedef struct BitReader {
31 unsigned last;
32 unsigned pos;
33 } BitReader;
34
35 typedef struct MOFLEXDemuxContext {
36 unsigned size;
37 int64_t pos;
38 int64_t ts;
39 int flags;
40 int in_block;
41
42 BitReader br;
43 } MOFLEXDemuxContext;
44
45 static int pop(BitReader *br, AVIOContext *pb)
46 {
47 if (avio_feof(pb))
48 return AVERROR_EOF;
49
50 if ((br->pos & 7) == 0)
51 br->last = (unsigned)avio_r8(pb) << 24U;
52 else
53 br->last <<= 1;
54
55 br->pos++;
56 return !!(br->last & 0x80000000);
57 }
58
59 static int pop_int(BitReader *br, AVIOContext *pb, int n)
60 {
61 int value = 0;
62
63 for (int i = 0; i < n; i++) {
64 int ret = pop(br, pb);
65
66 if (ret < 0)
67 return ret;
68 if (ret > INT_MAX - value - value)
69 return AVERROR_INVALIDDATA;
70 value = 2 * value + ret;
71 }
72
73 return value;
74 }
75
76 static int pop_length(BitReader *br, AVIOContext *pb)
77 {
78 int ret, n = 1;
79
80 while ((ret = pop(br, pb)) == 0)
81 n++;
82
83 if (ret < 0)
84 return ret;
85 return n;
86 }
87
88 static int read_var_byte(AVFormatContext *s, unsigned *out)
89 {
90 AVIOContext *pb = s->pb;
91 unsigned value = 0, data;
92
93 data = avio_r8(pb);
94 if (!(data & 0x80)) {
95 *out = data;
96 return 0;
97 }
98
99 value = (data & 0x7F) << 7;
100 data = avio_r8(pb);
101 if (!(data & 0x80)) {
102 value |= data;
103 *out = value;
104 return 0;
105 }
106
107 value = ((data & 0x7F) | value) << 7;
108 data = avio_r8(pb);
109 if (!(data & 0x80)) {
110 value |= data;
111 *out = value;
112 return 0;
113 }
114
115 value = (((data & 0x7F) | value) << 7) | avio_r8(pb);
116 *out = value;
117
118 return 0;
119 }
120
121 7128 static int moflex_probe(const AVProbeData *p)
122 {
123 GetByteContext gb;
124 7128 int score = 0;
125
126 7128 bytestream2_init(&gb, p->buf, p->buf_size);
127
128
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7128 if (bytestream2_get_be16(&gb) != 0x4C32)
129 7128 return 0;
130 score += 10;
131
132 bytestream2_skip(&gb, 10);
133 if (bytestream2_get_be16(&gb) == 0)
134 return 0;
135 score += 5;
136
137 while (bytestream2_get_bytes_left(&gb) > 0) {
138 int type = bytestream2_get_byte(&gb);
139 int size = bytestream2_get_byte(&gb);
140
141 if (type == 0) {
142 score += 5 * (size == 0);
143 break;
144 }
145 if ((type == 1 && size == 12) ||
146 (type == 2 && size == 6) ||
147 (type == 3 && size == 13) ||
148 (type == 4 && size == 2))
149 score += 20;
150 bytestream2_skip(&gb, size);
151 }
152
153 return FFMIN(AVPROBE_SCORE_MAX, score);
154 }
155
156 static int moflex_read_sync(AVFormatContext *s)
157 {
158 MOFLEXDemuxContext *m = s->priv_data;
159 AVIOContext *pb = s->pb;
160
161 if (avio_rb16(pb) != 0x4C32) {
162 if (avio_feof(pb))
163 return AVERROR_EOF;
164 avio_seek(pb, -2, SEEK_CUR);
165 return 1;
166 }
167
168 avio_skip(pb, 2);
169 m->ts = avio_rb64(pb);
170 m->size = avio_rb16(pb) + 1;
171
172 while (!avio_feof(pb)) {
173 unsigned type, ssize, codec_id = 0;
174 unsigned codec_type, width = 0, height = 0, sample_rate = 0, channels = 0;
175 int stream_index = -1;
176 AVRational tb = av_make_q(0, 1);
177
178 read_var_byte(s, &type);
179 read_var_byte(s, &ssize);
180
181 switch (type) {
182 case 0:
183 if (ssize > 0)
184 avio_skip(pb, ssize);
185 return 0;
186 case 2:
187 codec_type = AVMEDIA_TYPE_AUDIO;
188 stream_index = avio_r8(pb);
189 codec_id = avio_r8(pb);
190 switch (codec_id) {
191 case 0: codec_id = AV_CODEC_ID_FASTAUDIO; break;
192 case 1: codec_id = AV_CODEC_ID_ADPCM_IMA_MOFLEX; break;
193 case 2: codec_id = AV_CODEC_ID_PCM_S16LE; break;
194 default:
195 av_log(s, AV_LOG_ERROR, "Unsupported audio codec: %d\n", codec_id);
196 return AVERROR_PATCHWELCOME;
197 }
198 sample_rate = avio_rb24(pb) + 1;
199 tb = av_make_q(1, sample_rate);
200 channels = avio_r8(pb) + 1;
201 break;
202 case 1:
203 case 3:
204 codec_type = AVMEDIA_TYPE_VIDEO;
205 stream_index = avio_r8(pb);
206 codec_id = avio_r8(pb);
207 switch (codec_id) {
208 case 0: codec_id = AV_CODEC_ID_MOBICLIP; break;
209 default:
210 av_log(s, AV_LOG_ERROR, "Unsupported video codec: %d\n", codec_id);
211 return AVERROR_PATCHWELCOME;
212 }
213 tb.den = avio_rb16(pb);
214 tb.num = avio_rb16(pb);
215 width = avio_rb16(pb);
216 height = avio_rb16(pb);
217 avio_skip(pb, type == 3 ? 3 : 2);
218 break;
219 case 4:
220 codec_type = AVMEDIA_TYPE_DATA;
221 stream_index = avio_r8(pb);
222 avio_skip(pb, 1);
223 break;
224 }
225
226 if (stream_index == s->nb_streams) {
227 AVStream *st = avformat_new_stream(s, NULL);
228
229 if (!st)
230 return AVERROR(ENOMEM);
231
232 st->codecpar->codec_type = codec_type;
233 st->codecpar->codec_id = codec_id;
234 st->codecpar->width = width;
235 st->codecpar->height = height;
236 st->codecpar->sample_rate= sample_rate;
237 st->codecpar->ch_layout.nb_channels = channels;
238 st->priv_data = av_packet_alloc();
239 if (!st->priv_data)
240 return AVERROR(ENOMEM);
241
242 if (tb.num)
243 avpriv_set_pts_info(st, 63, tb.num, tb.den);
244 }
245 }
246
247 return 0;
248 }
249
250 static int moflex_read_header(AVFormatContext *s)
251 {
252 int ret;
253
254 ret = moflex_read_sync(s);
255 if (ret < 0)
256 return ret;
257
258 s->ctx_flags |= AVFMTCTX_NOHEADER;
259 avio_seek(s->pb, 0, SEEK_SET);
260
261 return 0;
262 }
263
264 static int moflex_read_packet(AVFormatContext *s, AVPacket *pkt)
265 {
266 MOFLEXDemuxContext *m = s->priv_data;
267 AVIOContext *pb = s->pb;
268 BitReader *br = &m->br;
269 int ret;
270
271 while (!avio_feof(pb)) {
272 if (!m->in_block) {
273 m->pos = avio_tell(pb);
274
275 ret = moflex_read_sync(s);
276 if (ret < 0)
277 return ret;
278
279 m->flags = avio_r8(pb);
280 if (m->flags & 2)
281 avio_skip(pb, 2);
282 }
283
284 while ((avio_tell(pb) < m->pos + m->size) && !avio_feof(pb) && avio_r8(pb)) {
285 int stream_index, bits, pkt_size, endframe;
286 AVPacket *packet;
287
288 m->in_block = 1;
289
290 avio_seek(pb, -1, SEEK_CUR);
291 br->pos = br->last = 0;
292
293 bits = pop_length(br, pb);
294 if (bits < 0)
295 return bits;
296 stream_index = pop_int(br, pb, bits);
297 if (stream_index < 0)
298 return stream_index;
299 if (stream_index >= s->nb_streams)
300 return AVERROR_INVALIDDATA;
301
302 endframe = pop(br, pb);
303 if (endframe < 0)
304 return endframe;
305 if (endframe) {
306 bits = pop_length(br, pb);
307 if (bits < 0)
308 return bits;
309 pop_int(br, pb, bits);
310 pop(br, pb);
311 bits = pop_length(br, pb);
312 if (bits < 0)
313 return bits;
314 pop_int(br, pb, bits * 2 + 26);
315 }
316
317 pkt_size = pop_int(br, pb, 13) + 1;
318 if (pkt_size > m->size)
319 return AVERROR_INVALIDDATA;
320 packet = s->streams[stream_index]->priv_data;
321 if (!packet) {
322 avio_skip(pb, pkt_size);
323 continue;
324 }
325
326 ret = av_append_packet(pb, packet, pkt_size);
327 if (ret < 0)
328 return ret;
329 if (endframe && packet->size > 0) {
330 av_packet_move_ref(pkt, packet);
331 pkt->pos = m->pos;
332 pkt->stream_index = stream_index;
333 if (s->streams[stream_index]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
334 pkt->duration = 1;
335 if (pkt->data[0] & 0x80)
336 pkt->flags |= AV_PKT_FLAG_KEY;
337 } else {
338 pkt->flags |= AV_PKT_FLAG_KEY;
339 }
340 return ret;
341 }
342 }
343
344 m->in_block = 0;
345
346 if (m->flags % 2 == 0) {
347 if (m->size <= 0)
348 return AVERROR_INVALIDDATA;
349 avio_seek(pb, m->pos + m->size, SEEK_SET);
350 }
351 }
352
353 return AVERROR_EOF;
354 }
355
356 static int moflex_read_seek(AVFormatContext *s, int stream_index,
357 int64_t pts, int flags)
358 {
359 MOFLEXDemuxContext *m = s->priv_data;
360
361 m->in_block = 0;
362
363 return -1;
364 }
365
366 static int moflex_read_close(AVFormatContext *s)
367 {
368 for (int i = 0; i < s->nb_streams; i++) {
369 av_packet_free((AVPacket **)&s->streams[i]->priv_data);
370 }
371
372 return 0;
373 }
374
375 const FFInputFormat ff_moflex_demuxer = {
376 .p.name = "moflex",
377 .p.long_name = NULL_IF_CONFIG_SMALL("MobiClip MOFLEX"),
378 .p.extensions = "moflex",
379 .p.flags = AVFMT_GENERIC_INDEX,
380 .priv_data_size = sizeof(MOFLEXDemuxContext),
381 .read_probe = moflex_probe,
382 .read_header = moflex_read_header,
383 .read_packet = moflex_read_packet,
384 .read_seek = moflex_read_seek,
385 .read_close = moflex_read_close,
386 .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,
387 };
388