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
;
155 return AV_CODEC_ID_NONE
;
158 AVInputFormat
*av_find_input_format(const char *short_name
)
160 AVInputFormat
*fmt
= NULL
;
161 while ((fmt
= av_iformat_next(fmt
)))
162 if (av_match_name(short_name
, fmt
->name
))
167 AVInputFormat
*av_probe_input_format3(AVProbeData
*pd
, int is_opened
,
170 AVProbeData lpd
= *pd
;
171 AVInputFormat
*fmt1
= NULL
, *fmt
;
172 int score
, nodat
= 0, score_max
= 0;
173 const static uint8_t zerobuffer
[AVPROBE_PADDING_SIZE
];
176 lpd
.buf
= zerobuffer
;
178 if (lpd
.buf_size
> 10 && ff_id3v2_match(lpd
.buf
, ID3v2_DEFAULT_MAGIC
)) {
179 int id3len
= ff_id3v2_tag_len(lpd
.buf
);
180 if (lpd
.buf_size
> id3len
+ 16) {
182 lpd
.buf_size
-= id3len
;
183 } else if (id3len
>= PROBE_BUF_MAX
) {
190 while ((fmt1
= av_iformat_next(fmt1
))) {
191 if (!is_opened
== !(fmt1
->flags
& AVFMT_NOFILE
) && strcmp(fmt1
->name
, "image2"))
194 if (fmt1
->read_probe
) {
195 score
= fmt1
->read_probe(&lpd
);
196 if (fmt1
->extensions
&& av_match_ext(lpd
.filename
, fmt1
->extensions
)) {
197 if (nodat
== 0) score
= FFMAX(score
, 1);
198 else if (nodat
== 1) score
= FFMAX(score
, AVPROBE_SCORE_EXTENSION
/ 2 - 1);
199 else score
= FFMAX(score
, AVPROBE_SCORE_EXTENSION
);
201 } else if (fmt1
->extensions
) {
202 if (av_match_ext(lpd
.filename
, fmt1
->extensions
))
203 score
= AVPROBE_SCORE_EXTENSION
;
205 if (av_match_name(lpd
.mime_type
, fmt1
->mime_type
))
206 score
= FFMAX(score
, AVPROBE_SCORE_MIME
);
207 if (score
> score_max
) {
210 } else if (score
== score_max
)
214 score_max
= FFMIN(AVPROBE_SCORE_EXTENSION
/ 2 - 1, score_max
);
215 *score_ret
= score_max
;
220 AVInputFormat
*av_probe_input_format2(AVProbeData
*pd
, int is_opened
, int *score_max
)
223 AVInputFormat
*fmt
= av_probe_input_format3(pd
, is_opened
, &score_ret
);
224 if (score_ret
> *score_max
) {
225 *score_max
= score_ret
;
231 AVInputFormat
*av_probe_input_format(AVProbeData
*pd
, int is_opened
)
234 return av_probe_input_format2(pd
, is_opened
, &score
);
237 int av_probe_input_buffer2(AVIOContext
*pb
, AVInputFormat
**fmt
,
238 const char *filename
, void *logctx
,
239 unsigned int offset
, unsigned int max_probe_size
)
241 AVProbeData pd
= { filename
? filename
: "" };
243 int ret
= 0, probe_size
, buf_offset
= 0;
248 max_probe_size
= PROBE_BUF_MAX
;
249 else if (max_probe_size
< PROBE_BUF_MIN
) {
250 av_log(logctx
, AV_LOG_ERROR
,
251 "Specified probe size value %u cannot be < %u\n", max_probe_size
, PROBE_BUF_MIN
);
252 return AVERROR(EINVAL
);
255 if (offset
>= max_probe_size
)
256 return AVERROR(EINVAL
);
259 uint8_t *mime_type_opt
= NULL
;
260 av_opt_get(pb
, "mime_type", AV_OPT_SEARCH_CHILDREN
, &mime_type_opt
);
261 pd
.mime_type
= (const char *)mime_type_opt
;
264 if (!*fmt
&& pb
->av_class
&& av_opt_get(pb
, "mime_type", AV_OPT_SEARCH_CHILDREN
, &mime_type
) >= 0 && mime_type
) {
265 if (!av_strcasecmp(mime_type
, "audio/aacp")) {
266 *fmt
= av_find_input_format("aac");
268 av_freep(&mime_type
);
272 for (probe_size
= PROBE_BUF_MIN
; probe_size
<= max_probe_size
&& !*fmt
;
273 probe_size
= FFMIN(probe_size
<< 1,
274 FFMAX(max_probe_size
, probe_size
+ 1))) {
275 score
= probe_size
< max_probe_size
? AVPROBE_SCORE_RETRY
: 0;
277 /* Read probe data. */
278 if ((ret
= av_reallocp(&buf
, probe_size
+ AVPROBE_PADDING_SIZE
)) < 0)
280 if ((ret
= avio_read(pb
, buf
+ buf_offset
,
281 probe_size
- buf_offset
)) < 0) {
282 /* Fail if error was not end of file, otherwise, lower score. */
283 if (ret
!= AVERROR_EOF
)
287 ret
= 0; /* error was end of file, nothing read */
290 if (buf_offset
< offset
)
292 pd
.buf_size
= buf_offset
- offset
;
293 pd
.buf
= &buf
[offset
];
295 memset(pd
.buf
+ pd
.buf_size
, 0, AVPROBE_PADDING_SIZE
);
297 /* Guess file format. */
298 *fmt
= av_probe_input_format2(&pd
, 1, &score
);
300 /* This can only be true in the last iteration. */
301 if (score
<= AVPROBE_SCORE_RETRY
) {
302 av_log(logctx
, AV_LOG_WARNING
,
303 "Format %s detected only with low score of %d, "
304 "misdetection possible!\n", (*fmt
)->name
, score
);
306 av_log(logctx
, AV_LOG_DEBUG
,
307 "Format %s probed with size=%d and score=%d\n",
308 (*fmt
)->name
, probe_size
, score
);
310 FILE *f
= fopen("probestat.tmp", "ab");
311 fprintf(f
, "probe_size:%d format:%s score:%d filename:%s\n", probe_size
, (*fmt
)->name
, score
, filename
);
318 ret
= AVERROR_INVALIDDATA
;
321 /* Rewind. Reuse probe buffer to avoid seeking. */
322 ret2
= ffio_rewind_with_probe_data(pb
, &buf
, buf_offset
);
326 av_freep(&pd
.mime_type
);
327 return ret
< 0 ? ret
: score
;
330 int av_probe_input_buffer(AVIOContext
*pb
, AVInputFormat
**fmt
,
331 const char *filename
, void *logctx
,
332 unsigned int offset
, unsigned int max_probe_size
)
334 int ret
= av_probe_input_buffer2(pb
, fmt
, filename
, logctx
, offset
, max_probe_size
);
335 return ret
< 0 ? ret
: 0;