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)
88 ext = strrchr(filename, '.');
90 return av_match_name(ext + 1, extensions);
94 AVOutputFormat *av_guess_format(const char *short_name, const char *filename,
95 const char *mime_type)
97 AVOutputFormat *fmt = NULL, *fmt_found;
100 /* specific test for image sequences */
101 #if CONFIG_IMAGE2_MUXER
102 if (!short_name && filename &&
103 av_filename_number_test(filename) &&
104 ff_guess_image2_codec(filename) != AV_CODEC_ID_NONE) {
105 return av_guess_format("image2", NULL, NULL);
108 /* Find the proper file type. */
111 while ((fmt = av_oformat_next(fmt))) {
113 if (fmt->name && short_name && av_match_name(short_name, fmt->name))
115 if (fmt->mime_type && mime_type && !strcmp(fmt->mime_type, mime_type))
117 if (filename && fmt->extensions &&
118 av_match_ext(filename, fmt->extensions)) {
121 if (score > score_max) {
129 enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
130 const char *filename, const char *mime_type,
131 enum AVMediaType type)
133 if (av_match_name("segment", fmt->name) || av_match_name("ssegment", fmt->name)) {
134 AVOutputFormat *fmt2 = av_guess_format(NULL, filename, NULL);
139 if (type == AVMEDIA_TYPE_VIDEO) {
140 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
142 #if CONFIG_IMAGE2_MUXER
143 if (!strcmp(fmt->name, "image2") || !strcmp(fmt->name, "image2pipe")) {
144 codec_id = ff_guess_image2_codec(filename);
147 if (codec_id == AV_CODEC_ID_NONE)
148 codec_id = fmt->video_codec;
150 } else if (type == AVMEDIA_TYPE_AUDIO)
151 return fmt->audio_codec;
152 else if (type == AVMEDIA_TYPE_SUBTITLE)
153 return fmt->subtitle_codec;
154 else if (type == AVMEDIA_TYPE_DATA)
155 return fmt->data_codec;
157 return AV_CODEC_ID_NONE;
160 AVInputFormat *av_find_input_format(const char *short_name)
162 AVInputFormat *fmt = NULL;
163 while ((fmt = av_iformat_next(fmt)))
164 if (av_match_name(short_name, fmt->name))
169 AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened,
172 AVProbeData lpd = *pd;
173 AVInputFormat *fmt1 = NULL, *fmt;
174 int score, score_max = 0;
175 const static uint8_t zerobuffer[AVPROBE_PADDING_SIZE];
178 ID3_ALMOST_GREATER_PROBE,
180 ID3_GREATER_MAX_PROBE,
184 lpd.buf = (unsigned char *) zerobuffer;
186 if (lpd.buf_size > 10 && ff_id3v2_match(lpd.buf, ID3v2_DEFAULT_MAGIC)) {
187 int id3len = ff_id3v2_tag_len(lpd.buf);
188 if (lpd.buf_size > id3len + 16) {
189 if (lpd.buf_size < 2LL*id3len + 16)
190 nodat = ID3_ALMOST_GREATER_PROBE;
192 lpd.buf_size -= id3len;
193 } else if (id3len >= PROBE_BUF_MAX) {
194 nodat = ID3_GREATER_MAX_PROBE;
196 nodat = ID3_GREATER_PROBE;
200 while ((fmt1 = av_iformat_next(fmt1))) {
201 if (!is_opened == !(fmt1->flags & AVFMT_NOFILE) && strcmp(fmt1->name, "image2"))
204 if (fmt1->read_probe) {
205 score = fmt1->read_probe(&lpd);
207 av_log(NULL, AV_LOG_TRACE, "Probing %s score:%d size:%d\n", fmt1->name, score, lpd.buf_size);
208 if (fmt1->extensions && av_match_ext(lpd.filename, fmt1->extensions)) {
211 score = FFMAX(score, 1);
213 case ID3_GREATER_PROBE:
214 case ID3_ALMOST_GREATER_PROBE:
215 score = FFMAX(score, AVPROBE_SCORE_EXTENSION / 2 - 1);
217 case ID3_GREATER_MAX_PROBE:
218 score = FFMAX(score, AVPROBE_SCORE_EXTENSION);
222 } else if (fmt1->extensions) {
223 if (av_match_ext(lpd.filename, fmt1->extensions))
224 score = AVPROBE_SCORE_EXTENSION;
226 if (av_match_name(lpd.mime_type, fmt1->mime_type)) {
227 if (AVPROBE_SCORE_MIME > score) {
228 av_log(NULL, AV_LOG_DEBUG, "Probing %s score:%d increased to %d due to MIME type\n", fmt1->name, score, AVPROBE_SCORE_MIME);
229 score = AVPROBE_SCORE_MIME;
232 if (score > score_max) {
235 } else if (score == score_max)
238 if (nodat == ID3_GREATER_PROBE)
239 score_max = FFMIN(AVPROBE_SCORE_EXTENSION / 2 - 1, score_max);
240 *score_ret = score_max;
245 AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max)
248 AVInputFormat *fmt = av_probe_input_format3(pd, is_opened, &score_ret);
249 if (score_ret > *score_max) {
250 *score_max = score_ret;
256 AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened)
259 return av_probe_input_format2(pd, is_opened, &score);
262 int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt,
263 const char *filename, void *logctx,
264 unsigned int offset, unsigned int max_probe_size)
266 AVProbeData pd = { filename ? filename : "" };
268 int ret = 0, probe_size, buf_offset = 0;
273 max_probe_size = PROBE_BUF_MAX;
274 else if (max_probe_size < PROBE_BUF_MIN) {
275 av_log(logctx, AV_LOG_ERROR,
276 "Specified probe size value %u cannot be < %u\n", max_probe_size, PROBE_BUF_MIN);
277 return AVERROR(EINVAL);
280 if (offset >= max_probe_size)
281 return AVERROR(EINVAL);
284 uint8_t *mime_type_opt = NULL;
286 av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type_opt);
287 pd.mime_type = (const char *)mime_type_opt;
288 semi = pd.mime_type ? strchr(pd.mime_type, ';') : NULL;
294 if (!*fmt && pb->av_class && av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type) >= 0 && mime_type) {
295 if (!av_strcasecmp(mime_type, "audio/aacp")) {
296 *fmt = av_find_input_format("aac");
298 av_freep(&mime_type);
302 for (probe_size = PROBE_BUF_MIN; probe_size <= max_probe_size && !*fmt;
303 probe_size = FFMIN(probe_size << 1,
304 FFMAX(max_probe_size, probe_size + 1))) {
305 score = probe_size < max_probe_size ? AVPROBE_SCORE_RETRY : 0;
307 /* Read probe data. */
308 if ((ret = av_reallocp(&buf, probe_size + AVPROBE_PADDING_SIZE)) < 0)
310 if ((ret = avio_read(pb, buf + buf_offset,
311 probe_size - buf_offset)) < 0) {
312 /* Fail if error was not end of file, otherwise, lower score. */
313 if (ret != AVERROR_EOF)
317 ret = 0; /* error was end of file, nothing read */
320 if (buf_offset < offset)
322 pd.buf_size = buf_offset - offset;
323 pd.buf = &buf[offset];
325 memset(pd.buf + pd.buf_size, 0, AVPROBE_PADDING_SIZE);
327 /* Guess file format. */
328 *fmt = av_probe_input_format2(&pd, 1, &score);
330 /* This can only be true in the last iteration. */
331 if (score <= AVPROBE_SCORE_RETRY) {
332 av_log(logctx, AV_LOG_WARNING,
333 "Format %s detected only with low score of %d, "
334 "misdetection possible!\n", (*fmt)->name, score);
336 av_log(logctx, AV_LOG_DEBUG,
337 "Format %s probed with size=%d and score=%d\n",
338 (*fmt)->name, probe_size, score);
340 FILE *f = fopen("probestat.tmp", "ab");
341 fprintf(f, "probe_size:%d format:%s score:%d filename:%s\n", probe_size, (*fmt)->name, score, filename);
348 ret = AVERROR_INVALIDDATA;
351 /* Rewind. Reuse probe buffer to avoid seeking. */
352 ret2 = ffio_rewind_with_probe_data(pb, &buf, buf_offset);
356 av_freep(&pd.mime_type);
357 return ret < 0 ? ret : score;
360 int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
361 const char *filename, void *logctx,
362 unsigned int offset, unsigned int max_probe_size)
364 int ret = av_probe_input_buffer2(pb, fmt, filename, logctx, offset, max_probe_size);
365 return ret < 0 ? ret : 0;