2 * Format register and lookup
3 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavutil/atomic.h"
23 #include "libavutil/avstring.h"
24 #include "libavutil/bprint.h"
25 #include "libavutil/opt.h"
27 #include "avio_internal.h"
35 * Format register and lookup
37 /** head of registered input format linked list */
38 static AVInputFormat *first_iformat = NULL;
39 /** head of registered output format linked list */
40 static AVOutputFormat *first_oformat = NULL;
42 static AVInputFormat **last_iformat = &first_iformat;
43 static AVOutputFormat **last_oformat = &first_oformat;
45 AVInputFormat *av_iformat_next(const AVInputFormat *f)
53 AVOutputFormat *av_oformat_next(const AVOutputFormat *f)
61 void av_register_input_format(AVInputFormat *format)
63 AVInputFormat **p = last_iformat;
66 while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))
68 last_iformat = &format->next;
71 void av_register_output_format(AVOutputFormat *format)
73 AVOutputFormat **p = last_oformat;
76 while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))
78 last_oformat = &format->next;
81 int av_match_ext(const char *filename, const char *extensions)
89 ext = strrchr(filename, '.');
95 while (*p != '\0' && *p != ',' && q - ext1 < sizeof(ext1) - 1)
98 if (!av_strcasecmp(ext1, ext))
108 AVOutputFormat *av_guess_format(const char *short_name, const char *filename,
109 const char *mime_type)
111 AVOutputFormat *fmt = NULL, *fmt_found;
112 int score_max, score;
114 /* specific test for image sequences */
115 #if CONFIG_IMAGE2_MUXER
116 if (!short_name && filename &&
117 av_filename_number_test(filename) &&
118 ff_guess_image2_codec(filename) != AV_CODEC_ID_NONE) {
119 return av_guess_format("image2", NULL, NULL);
122 /* Find the proper file type. */
125 while ((fmt = av_oformat_next(fmt))) {
127 if (fmt->name && short_name && av_match_name(short_name, fmt->name))
129 if (fmt->mime_type && mime_type && !strcmp(fmt->mime_type, mime_type))
131 if (filename && fmt->extensions &&
132 av_match_ext(filename, fmt->extensions)) {
135 if (score > score_max) {
143 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
144 const char *filename, const char *mime_type,
145 enum AVMediaType type)
147 if (av_match_name("segment", fmt->name) || av_match_name("ssegment", fmt->name)) {
148 AVOutputFormat *fmt2 = av_guess_format(NULL, filename, NULL);
153 if (type == AVMEDIA_TYPE_VIDEO) {
154 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
156 #if CONFIG_IMAGE2_MUXER
157 if (!strcmp(fmt->name, "image2") || !strcmp(fmt->name, "image2pipe")) {
158 codec_id = ff_guess_image2_codec(filename);
161 if (codec_id == AV_CODEC_ID_NONE)
162 codec_id = fmt->video_codec;
164 } else if (type == AVMEDIA_TYPE_AUDIO)
165 return fmt->audio_codec;
166 else if (type == AVMEDIA_TYPE_SUBTITLE)
167 return fmt->subtitle_codec;
169 return AV_CODEC_ID_NONE;
172 AVInputFormat *av_find_input_format(const char *short_name)
174 AVInputFormat *fmt = NULL;
175 while ((fmt = av_iformat_next(fmt)))
176 if (av_match_name(short_name, fmt->name))
181 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened,
184 AVProbeData lpd = *pd;
185 AVInputFormat *fmt1 = NULL, *fmt;
186 int score, nodat = 0, score_max = 0;
187 const static uint8_t zerobuffer[AVPROBE_PADDING_SIZE];
190 lpd.buf = zerobuffer;
192 if (lpd.buf_size > 10 && ff_id3v2_match(lpd.buf, ID3v2_DEFAULT_MAGIC)) {
193 int id3len = ff_id3v2_tag_len(lpd.buf);
194 if (lpd.buf_size > id3len + 16) {
196 lpd.buf_size -= id3len;
197 } else if (id3len >= PROBE_BUF_MAX) {
204 while ((fmt1 = av_iformat_next(fmt1))) {
205 if (!is_opened == !(fmt1->flags & AVFMT_NOFILE))
208 if (fmt1->read_probe) {
209 score = fmt1->read_probe(&lpd);
210 if (fmt1->extensions && av_match_ext(lpd.filename, fmt1->extensions)) {
211 if (nodat == 0) score = FFMAX(score, 1);
212 else if (nodat == 1) score = FFMAX(score, AVPROBE_SCORE_EXTENSION / 2 - 1);
213 else score = FFMAX(score, AVPROBE_SCORE_EXTENSION);
215 } else if (fmt1->extensions) {
216 if (av_match_ext(lpd.filename, fmt1->extensions))
217 score = AVPROBE_SCORE_EXTENSION;
219 if (av_match_name(lpd.mime_type, fmt1->mime_type))
220 score = FFMAX(score, AVPROBE_SCORE_EXTENSION);
221 if (score > score_max) {
224 } else if (score == score_max)
228 score_max = FFMIN(AVPROBE_SCORE_EXTENSION / 2 - 1, score_max);
229 *score_ret = score_max;
234 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max)
237 AVInputFormat *fmt = av_probe_input_format3(pd, is_opened, &score_ret);
238 if (score_ret > *score_max) {
239 *score_max = score_ret;
245 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened)
248 return av_probe_input_format2(pd, is_opened, &score);
251 int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt,
252 const char *filename, void *logctx,
253 unsigned int offset, unsigned int max_probe_size)
255 AVProbeData pd = { filename ? filename : "" };
257 int ret = 0, probe_size, buf_offset = 0;
262 max_probe_size = PROBE_BUF_MAX;
263 else if (max_probe_size < PROBE_BUF_MIN) {
264 av_log(logctx, AV_LOG_ERROR,
265 "Specified probe size value %u cannot be < %u\n", max_probe_size, PROBE_BUF_MIN);
266 return AVERROR(EINVAL);
269 if (offset >= max_probe_size)
270 return AVERROR(EINVAL);
273 av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &pd.mime_type);
275 if (!*fmt && pb->av_class && av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type) >= 0 && mime_type) {
276 if (!av_strcasecmp(mime_type, "audio/aacp")) {
277 *fmt = av_find_input_format("aac");
279 av_freep(&mime_type);
283 for (probe_size = PROBE_BUF_MIN; probe_size <= max_probe_size && !*fmt;
284 probe_size = FFMIN(probe_size << 1,
285 FFMAX(max_probe_size, probe_size + 1))) {
286 score = probe_size < max_probe_size ? AVPROBE_SCORE_RETRY : 0;
288 /* Read probe data. */
289 if ((ret = av_reallocp(&buf, probe_size + AVPROBE_PADDING_SIZE)) < 0)
291 if ((ret = avio_read(pb, buf + buf_offset,
292 probe_size - buf_offset)) < 0) {
293 /* Fail if error was not end of file, otherwise, lower score. */
294 if (ret != AVERROR_EOF)
298 ret = 0; /* error was end of file, nothing read */
301 if (buf_offset < offset)
303 pd.buf_size = buf_offset - offset;
304 pd.buf = &buf[offset];
306 memset(pd.buf + pd.buf_size, 0, AVPROBE_PADDING_SIZE);
308 /* Guess file format. */
309 *fmt = av_probe_input_format2(&pd, 1, &score);
311 /* This can only be true in the last iteration. */
312 if (score <= AVPROBE_SCORE_RETRY) {
313 av_log(logctx, AV_LOG_WARNING,
314 "Format %s detected only with low score of %d, "
315 "misdetection possible!\n", (*fmt)->name, score);
317 av_log(logctx, AV_LOG_DEBUG,
318 "Format %s probed with size=%d and score=%d\n",
319 (*fmt)->name, probe_size, score);
321 FILE *f = fopen("probestat.tmp", "ab");
322 fprintf(f, "probe_size:%d format:%s score:%d filename:%s\n", probe_size, (*fmt)->name, score, filename);
329 ret = AVERROR_INVALIDDATA;
332 /* Rewind. Reuse probe buffer to avoid seeking. */
333 ret2 = ffio_rewind_with_probe_data(pb, &buf, buf_offset);
337 av_free(pd.mime_type);
338 return ret < 0 ? ret : score;
341 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
342 const char *filename, void *logctx,
343 unsigned int offset, unsigned int max_probe_size)
345 int ret = av_probe_input_buffer2(pb, fmt, filename, logctx, offset, max_probe_size);
346 return ret < 0 ? ret : 0;