diff options
Diffstat (limited to 'libavformat/concatdec.c')
| -rw-r--r-- | libavformat/concatdec.c | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/libavformat/concatdec.c b/libavformat/concatdec.c new file mode 100644 index 0000000000..428c749ab2 --- /dev/null +++ b/libavformat/concatdec.c @@ -0,0 +1,408 @@ +/* + * Copyright (c) 2012 Nicolas George + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public License + * as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with FFmpeg; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "libavutil/avstring.h" +#include "libavutil/opt.h" +#include "libavutil/parseutils.h" +#include "avformat.h" +#include "internal.h" +#include "url.h" + +typedef struct { + char *url; + int64_t start_time; + int64_t duration; +} ConcatFile; + +typedef struct { + AVClass *class; + ConcatFile *files; + ConcatFile *cur_file; + unsigned nb_files; + AVFormatContext *avf; + int safe; + int seekable; +} ConcatContext; + +static int concat_probe(AVProbeData *probe) +{ + return memcmp(probe->buf, "ffconcat version 1.0", 20) ? + 0 : AVPROBE_SCORE_MAX; +} + +static char *get_keyword(uint8_t **cursor) +{ + char *ret = *cursor += strspn(*cursor, SPACE_CHARS); + *cursor += strcspn(*cursor, SPACE_CHARS); + if (**cursor) { + *((*cursor)++) = 0; + *cursor += strspn(*cursor, SPACE_CHARS); + } + return ret; +} + +static int safe_filename(const char *f) +{ + const char *start = f; + + for (; *f; f++) { + /* A-Za-z0-9_- */ + if (!((unsigned)((*f | 32) - 'a') < 26 || + (unsigned)(*f - '0') < 10 || *f == '_' || *f == '-')) { + if (f == start) + return 0; + else if (*f == '/') + start = f + 1; + else if (*f != '.') + return 0; + } + } + return 1; +} + +#define FAIL(retcode) do { ret = (retcode); goto fail; } while(0) + +static int add_file(AVFormatContext *avf, char *filename, ConcatFile **rfile, + unsigned *nb_files_alloc) +{ + ConcatContext *cat = avf->priv_data; + ConcatFile *file; + char *url = NULL; + size_t url_len; + int ret; + + if (cat->safe > 0 && !safe_filename(filename)) { + av_log(avf, AV_LOG_ERROR, "Unsafe file name '%s'\n", filename); + FAIL(AVERROR(EPERM)); + } + url_len = strlen(avf->filename) + strlen(filename) + 16; + if (!(url = av_malloc(url_len))) + FAIL(AVERROR(ENOMEM)); + ff_make_absolute_url(url, url_len, avf->filename, filename); + av_freep(&filename); + + if (cat->nb_files >= *nb_files_alloc) { + size_t n = FFMAX(*nb_files_alloc * 2, 16); + ConcatFile *new_files; + if (n <= cat->nb_files || n > SIZE_MAX / sizeof(*cat->files) || + !(new_files = av_realloc(cat->files, n * sizeof(*cat->files)))) + FAIL(AVERROR(ENOMEM)); + cat->files = new_files; + *nb_files_alloc = n; + } + + file = &cat->files[cat->nb_files++]; + memset(file, 0, sizeof(*file)); + *rfile = file; + + file->url = url; + file->start_time = AV_NOPTS_VALUE; + file->duration = AV_NOPTS_VALUE; + + return 0; + +fail: + av_free(url); + av_free(filename); + return ret; +} + +static int open_file(AVFormatContext *avf, unsigned fileno) +{ + ConcatContext *cat = avf->priv_data; + ConcatFile *file = &cat->files[fileno]; + int ret; + + if (cat->avf) + avformat_close_input(&cat->avf); + if ((ret = avformat_open_input(&cat->avf, file->url, NULL, NULL)) < 0 || + (ret = avformat_find_stream_info(cat->avf, NULL)) < 0) { + av_log(avf, AV_LOG_ERROR, "Impossible to open '%s'\n", file->url); + return ret; + } + cat->cur_file = file; + if (file->start_time == AV_NOPTS_VALUE) + file->start_time = !fileno ? 0 : + cat->files[fileno - 1].start_time + + cat->files[fileno - 1].duration; + return 0; +} + +static int concat_read_close(AVFormatContext *avf) +{ + ConcatContext *cat = avf->priv_data; + unsigned i; + + if (cat->avf) + avformat_close_input(&cat->avf); + for (i = 0; i < cat->nb_files; i++) + av_freep(&cat->files[i].url); + av_freep(&cat->files); + return 0; +} + +static int concat_read_header(AVFormatContext *avf) +{ + ConcatContext *cat = avf->priv_data; + uint8_t buf[4096]; + uint8_t *cursor, *keyword; + int ret, line = 0, i; + unsigned nb_files_alloc = 0; + ConcatFile *file = NULL; + AVStream *st, *source_st; + int64_t time = 0; + + while (1) { + if ((ret = ff_get_line(avf->pb, buf, sizeof(buf))) <= 0) + break; + line++; + cursor = buf; + keyword = get_keyword(&cursor); + if (!*keyword || *keyword == '#') + continue; + + if (!strcmp(keyword, "file")) { + char *filename = av_get_token((const char **)&cursor, SPACE_CHARS); + if (!filename) { + av_log(avf, AV_LOG_ERROR, "Line %d: filename required\n", line); + FAIL(AVERROR_INVALIDDATA); + } + if ((ret = add_file(avf, filename, &file, &nb_files_alloc)) < 0) + FAIL(ret); + } else if (!strcmp(keyword, "duration")) { + char *dur_str = get_keyword(&cursor); + int64_t dur; + if (!file) { + av_log(avf, AV_LOG_ERROR, "Line %d: duration without file\n", + line); + FAIL(AVERROR_INVALIDDATA); + } + if ((ret = av_parse_time(&dur, dur_str, 1)) < 0) { + av_log(avf, AV_LOG_ERROR, "Line %d: invalid duration '%s'\n", + line, dur_str); + FAIL(ret); + } + file->duration = dur; + } else if (!strcmp(keyword, "ffconcat")) { + char *ver_kw = get_keyword(&cursor); + char *ver_val = get_keyword(&cursor); + if (strcmp(ver_kw, "version") || strcmp(ver_val, "1.0")) { + av_log(avf, AV_LOG_ERROR, "Line %d: invalid version\n", line); + FAIL(AVERROR_INVALIDDATA); + } + if (cat->safe < 0) + cat->safe = 1; + } else { + av_log(avf, AV_LOG_ERROR, "Line %d: unknown keyword '%s'\n", + line, keyword); + FAIL(AVERROR_INVALIDDATA); + } + } + if (ret < 0) + FAIL(ret); + if (!cat->nb_files) + FAIL(AVERROR_INVALIDDATA); + + for (i = 0; i < cat->nb_files; i++) { + if (cat->files[i].start_time == AV_NOPTS_VALUE) + cat->files[i].start_time = time; + else + time = cat->files[i].start_time; + if (cat->files[i].duration == AV_NOPTS_VALUE) + break; + time += cat->files[i].duration; + } + if (i == cat->nb_files) { + avf->duration = time; + cat->seekable = 1; + } + + if ((ret = open_file(avf, 0)) < 0) + FAIL(ret); + for (i = 0; i < cat->avf->nb_streams; i++) { + if (!(st = avformat_new_stream(avf, NULL))) + FAIL(AVERROR(ENOMEM)); + source_st = cat->avf->streams[i]; + if ((ret = avcodec_copy_context(st->codec, source_st->codec)) < 0) + FAIL(ret); + st->r_frame_rate = source_st->r_frame_rate; + st->avg_frame_rate = source_st->avg_frame_rate; + st->time_base = source_st->time_base; + st->sample_aspect_ratio = source_st->sample_aspect_ratio; + } + + return 0; + +fail: + concat_read_close(avf); + return ret; +} + +static int open_next_file(AVFormatContext *avf) +{ + ConcatContext *cat = avf->priv_data; + unsigned fileno = cat->cur_file - cat->files; + + if (cat->cur_file->duration == AV_NOPTS_VALUE) + cat->cur_file->duration = cat->avf->duration; + + if (++fileno >= cat->nb_files) + return AVERROR_EOF; + return open_file(avf, fileno); +} + +static int concat_read_packet(AVFormatContext *avf, AVPacket *pkt) +{ + ConcatContext *cat = avf->priv_data; + int ret; + int64_t delta; + + while (1) { + if ((ret = av_read_frame(cat->avf, pkt)) != AVERROR_EOF || + (ret = open_next_file(avf)) < 0) + break; + } + delta = av_rescale_q(cat->cur_file->start_time - cat->avf->start_time, + AV_TIME_BASE_Q, + cat->avf->streams[pkt->stream_index]->time_base); + if (pkt->pts != AV_NOPTS_VALUE) + pkt->pts += delta; + if (pkt->dts != AV_NOPTS_VALUE) + pkt->dts += delta; + return ret; +} + +static void rescale_interval(AVRational tb_in, AVRational tb_out, + int64_t *min_ts, int64_t *ts, int64_t *max_ts) +{ + *ts = av_rescale_q (* ts, tb_in, tb_out); + *min_ts = av_rescale_q_rnd(*min_ts, tb_in, tb_out, + AV_ROUND_UP | AV_ROUND_PASS_MINMAX); + *max_ts = av_rescale_q_rnd(*max_ts, tb_in, tb_out, + AV_ROUND_DOWN | AV_ROUND_PASS_MINMAX); +} + +static int try_seek(AVFormatContext *avf, int stream, + int64_t min_ts, int64_t ts, int64_t max_ts, int flags) +{ + ConcatContext *cat = avf->priv_data; + int64_t t0 = cat->cur_file->start_time - cat->avf->start_time; + + ts -= t0; + min_ts = min_ts == INT64_MIN ? INT64_MIN : min_ts - t0; + max_ts = max_ts == INT64_MAX ? INT64_MAX : max_ts - t0; + if (stream >= 0) { + if (stream >= cat->avf->nb_streams) + return AVERROR(EIO); + rescale_interval(AV_TIME_BASE_Q, cat->avf->streams[stream]->time_base, + &min_ts, &ts, &max_ts); + } + return avformat_seek_file(cat->avf, stream, min_ts, ts, max_ts, flags); +} + +static int real_seek(AVFormatContext *avf, int stream, + int64_t min_ts, int64_t ts, int64_t max_ts, int flags) +{ + ConcatContext *cat = avf->priv_data; + int ret, left, right; + + if (stream >= 0) { + if (stream >= avf->nb_streams) + return AVERROR(EINVAL); + rescale_interval(avf->streams[stream]->time_base, AV_TIME_BASE_Q, + &min_ts, &ts, &max_ts); + } + + left = 0; + right = cat->nb_files; + while (right - left > 1) { + int mid = (left + right) / 2; + if (ts < cat->files[mid].start_time) + right = mid; + else + left = mid; + } + + if ((ret = open_file(avf, left)) < 0) + return ret; + + ret = try_seek(avf, stream, min_ts, ts, max_ts, flags); + if (ret < 0 && + left < cat->nb_files - 1 && + cat->files[left + 1].start_time < max_ts) { + if ((ret = open_file(avf, left + 1)) < 0) + return ret; + ret = try_seek(avf, stream, min_ts, ts, max_ts, flags); + } + return ret; +} + +static int concat_seek(AVFormatContext *avf, int stream, + int64_t min_ts, int64_t ts, int64_t max_ts, int flags) +{ + ConcatContext *cat = avf->priv_data; + ConcatFile *cur_file_saved = cat->cur_file; + AVFormatContext *cur_avf_saved = cat->avf; + int ret; + + if (!cat->seekable) + return AVERROR(ESPIPE); /* XXX: can we use it? */ + if (flags & (AVSEEK_FLAG_BYTE | AVSEEK_FLAG_FRAME)) + return AVERROR(ENOSYS); + cat->avf = NULL; + if ((ret = real_seek(avf, stream, min_ts, ts, max_ts, flags)) < 0) { + if (cat->avf) + avformat_close_input(&cat->avf); + cat->avf = cur_avf_saved; + cat->cur_file = cur_file_saved; + } else { + avformat_close_input(&cur_avf_saved); + } + return ret; +} + +#define OFFSET(x) offsetof(ConcatContext, x) +#define DEC AV_OPT_FLAG_DECODING_PARAM + +static const AVOption options[] = { + { "safe", "enable safe mode", + OFFSET(safe), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 1, DEC }, + { NULL } +}; + +static const AVClass concat_class = { + .class_name = "concat demuxer", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + + +AVInputFormat ff_concat_demuxer = { + .name = "concat", + .long_name = NULL_IF_CONFIG_SMALL("Virtual concatenation script"), + .priv_data_size = sizeof(ConcatContext), + .read_probe = concat_probe, + .read_header = concat_read_header, + .read_packet = concat_read_packet, + .read_close = concat_read_close, + .read_seek2 = concat_seek, + .priv_class = &concat_class, +}; |