| 1 | /* |
| 2 | * Format register and lookup |
| 3 | * Copyright (c) 2000, 2001, 2002 Fabrice Bellard |
| 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 | #include "libavutil/atomic.h" |
| 23 | #include "libavutil/avstring.h" |
| 24 | #include "libavutil/bprint.h" |
| 25 | #include "libavutil/opt.h" |
| 26 | |
| 27 | #include "avio_internal.h" |
| 28 | #include "avformat.h" |
| 29 | #include "id3v2.h" |
| 30 | #include "internal.h" |
| 31 | |
| 32 | |
| 33 | /** |
| 34 | * @file |
| 35 | * Format register and lookup |
| 36 | */ |
| 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; |
| 41 | |
| 42 | static AVInputFormat **last_iformat = &first_iformat; |
| 43 | static AVOutputFormat **last_oformat = &first_oformat; |
| 44 | |
| 45 | AVInputFormat *av_iformat_next(const AVInputFormat *f) |
| 46 | { |
| 47 | if (f) |
| 48 | return f->next; |
| 49 | else |
| 50 | return first_iformat; |
| 51 | } |
| 52 | |
| 53 | AVOutputFormat *av_oformat_next(const AVOutputFormat *f) |
| 54 | { |
| 55 | if (f) |
| 56 | return f->next; |
| 57 | else |
| 58 | return first_oformat; |
| 59 | } |
| 60 | |
| 61 | void av_register_input_format(AVInputFormat *format) |
| 62 | { |
| 63 | AVInputFormat **p = last_iformat; |
| 64 | |
| 65 | format->next = NULL; |
| 66 | while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format)) |
| 67 | p = &(*p)->next; |
| 68 | last_iformat = &format->next; |
| 69 | } |
| 70 | |
| 71 | void av_register_output_format(AVOutputFormat *format) |
| 72 | { |
| 73 | AVOutputFormat **p = last_oformat; |
| 74 | |
| 75 | format->next = NULL; |
| 76 | while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format)) |
| 77 | p = &(*p)->next; |
| 78 | last_oformat = &format->next; |
| 79 | } |
| 80 | |
| 81 | int av_match_ext(const char *filename, const char *extensions) |
| 82 | { |
| 83 | const char *ext; |
| 84 | |
| 85 | if (!filename) |
| 86 | return 0; |
| 87 | |
| 88 | ext = strrchr(filename, '.'); |
| 89 | if (ext) |
| 90 | return av_match_name(ext + 1, extensions); |
| 91 | return 0; |
| 92 | } |
| 93 | |
| 94 | AVOutputFormat *av_guess_format(const char *short_name, const char *filename, |
| 95 | const char *mime_type) |
| 96 | { |
| 97 | AVOutputFormat *fmt = NULL, *fmt_found; |
| 98 | int score_max, score; |
| 99 | |
| 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); |
| 106 | } |
| 107 | #endif |
| 108 | /* Find the proper file type. */ |
| 109 | fmt_found = NULL; |
| 110 | score_max = 0; |
| 111 | while ((fmt = av_oformat_next(fmt))) { |
| 112 | score = 0; |
| 113 | if (fmt->name && short_name && av_match_name(short_name, fmt->name)) |
| 114 | score += 100; |
| 115 | if (fmt->mime_type && mime_type && !strcmp(fmt->mime_type, mime_type)) |
| 116 | score += 10; |
| 117 | if (filename && fmt->extensions && |
| 118 | av_match_ext(filename, fmt->extensions)) { |
| 119 | score += 5; |
| 120 | } |
| 121 | if (score > score_max) { |
| 122 | score_max = score; |
| 123 | fmt_found = fmt; |
| 124 | } |
| 125 | } |
| 126 | return fmt_found; |
| 127 | } |
| 128 | |
| 129 | enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, |
| 130 | const char *filename, const char *mime_type, |
| 131 | enum AVMediaType type) |
| 132 | { |
| 133 | if (av_match_name("segment", fmt->name) || av_match_name("ssegment", fmt->name)) { |
| 134 | AVOutputFormat *fmt2 = av_guess_format(NULL, filename, NULL); |
| 135 | if (fmt2) |
| 136 | fmt = fmt2; |
| 137 | } |
| 138 | |
| 139 | if (type == AVMEDIA_TYPE_VIDEO) { |
| 140 | enum AVCodecID codec_id = AV_CODEC_ID_NONE; |
| 141 | |
| 142 | #if CONFIG_IMAGE2_MUXER |
| 143 | if (!strcmp(fmt->name, "image2") || !strcmp(fmt->name, "image2pipe")) { |
| 144 | codec_id = ff_guess_image2_codec(filename); |
| 145 | } |
| 146 | #endif |
| 147 | if (codec_id == AV_CODEC_ID_NONE) |
| 148 | codec_id = fmt->video_codec; |
| 149 | return codec_id; |
| 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 |
| 155 | return AV_CODEC_ID_NONE; |
| 156 | } |
| 157 | |
| 158 | AVInputFormat *av_find_input_format(const char *short_name) |
| 159 | { |
| 160 | AVInputFormat *fmt = NULL; |
| 161 | while ((fmt = av_iformat_next(fmt))) |
| 162 | if (av_match_name(short_name, fmt->name)) |
| 163 | return fmt; |
| 164 | return NULL; |
| 165 | } |
| 166 | |
| 167 | AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, |
| 168 | int *score_ret) |
| 169 | { |
| 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]; |
| 174 | |
| 175 | if (!lpd.buf) |
| 176 | lpd.buf = zerobuffer; |
| 177 | |
| 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) { |
| 181 | lpd.buf += id3len; |
| 182 | lpd.buf_size -= id3len; |
| 183 | } else if (id3len >= PROBE_BUF_MAX) { |
| 184 | nodat = 2; |
| 185 | } else |
| 186 | nodat = 1; |
| 187 | } |
| 188 | |
| 189 | fmt = NULL; |
| 190 | while ((fmt1 = av_iformat_next(fmt1))) { |
| 191 | if (!is_opened == !(fmt1->flags & AVFMT_NOFILE) && strcmp(fmt1->name, "image2")) |
| 192 | continue; |
| 193 | score = 0; |
| 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); |
| 200 | } |
| 201 | } else if (fmt1->extensions) { |
| 202 | if (av_match_ext(lpd.filename, fmt1->extensions)) |
| 203 | score = AVPROBE_SCORE_EXTENSION; |
| 204 | } |
| 205 | if (av_match_name(lpd.mime_type, fmt1->mime_type)) |
| 206 | score = FFMAX(score, AVPROBE_SCORE_MIME); |
| 207 | if (score > score_max) { |
| 208 | score_max = score; |
| 209 | fmt = fmt1; |
| 210 | } else if (score == score_max) |
| 211 | fmt = NULL; |
| 212 | } |
| 213 | if (nodat == 1) |
| 214 | score_max = FFMIN(AVPROBE_SCORE_EXTENSION / 2 - 1, score_max); |
| 215 | *score_ret = score_max; |
| 216 | |
| 217 | return fmt; |
| 218 | } |
| 219 | |
| 220 | AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max) |
| 221 | { |
| 222 | int score_ret; |
| 223 | AVInputFormat *fmt = av_probe_input_format3(pd, is_opened, &score_ret); |
| 224 | if (score_ret > *score_max) { |
| 225 | *score_max = score_ret; |
| 226 | return fmt; |
| 227 | } else |
| 228 | return NULL; |
| 229 | } |
| 230 | |
| 231 | AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened) |
| 232 | { |
| 233 | int score = 0; |
| 234 | return av_probe_input_format2(pd, is_opened, &score); |
| 235 | } |
| 236 | |
| 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) |
| 240 | { |
| 241 | AVProbeData pd = { filename ? filename : "" }; |
| 242 | uint8_t *buf = NULL; |
| 243 | int ret = 0, probe_size, buf_offset = 0; |
| 244 | int score = 0; |
| 245 | int ret2; |
| 246 | |
| 247 | if (!max_probe_size) |
| 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); |
| 253 | } |
| 254 | |
| 255 | if (offset >= max_probe_size) |
| 256 | return AVERROR(EINVAL); |
| 257 | |
| 258 | if (pb->av_class) { |
| 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; |
| 262 | } |
| 263 | #if 0 |
| 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"); |
| 267 | } |
| 268 | av_freep(&mime_type); |
| 269 | } |
| 270 | #endif |
| 271 | |
| 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; |
| 276 | |
| 277 | /* Read probe data. */ |
| 278 | if ((ret = av_reallocp(&buf, probe_size + AVPROBE_PADDING_SIZE)) < 0) |
| 279 | goto fail; |
| 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) |
| 284 | goto fail; |
| 285 | |
| 286 | score = 0; |
| 287 | ret = 0; /* error was end of file, nothing read */ |
| 288 | } |
| 289 | buf_offset += ret; |
| 290 | if (buf_offset < offset) |
| 291 | continue; |
| 292 | pd.buf_size = buf_offset - offset; |
| 293 | pd.buf = &buf[offset]; |
| 294 | |
| 295 | memset(pd.buf + pd.buf_size, 0, AVPROBE_PADDING_SIZE); |
| 296 | |
| 297 | /* Guess file format. */ |
| 298 | *fmt = av_probe_input_format2(&pd, 1, &score); |
| 299 | if (*fmt) { |
| 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); |
| 305 | } else |
| 306 | av_log(logctx, AV_LOG_DEBUG, |
| 307 | "Format %s probed with size=%d and score=%d\n", |
| 308 | (*fmt)->name, probe_size, score); |
| 309 | #if 0 |
| 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); |
| 312 | fclose(f); |
| 313 | #endif |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | if (!*fmt) |
| 318 | ret = AVERROR_INVALIDDATA; |
| 319 | |
| 320 | fail: |
| 321 | /* Rewind. Reuse probe buffer to avoid seeking. */ |
| 322 | ret2 = ffio_rewind_with_probe_data(pb, &buf, buf_offset); |
| 323 | if (ret >= 0) |
| 324 | ret = ret2; |
| 325 | |
| 326 | av_freep(&pd.mime_type); |
| 327 | return ret < 0 ? ret : score; |
| 328 | } |
| 329 | |
| 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) |
| 333 | { |
| 334 | int ret = av_probe_input_buffer2(pb, fmt, filename, logctx, offset, max_probe_size); |
| 335 | return ret < 0 ? ret : 0; |
| 336 | } |