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-rw-r--r--libavformat/concatdec.c407
1 files changed, 407 insertions, 0 deletions
diff --git a/libavformat/concatdec.c b/libavformat/concatdec.c
new file mode 100644
index 0000000000..79fb394d45
--- /dev/null
+++ b/libavformat/concatdec.c
@@ -0,0 +1,407 @@
+/*
+ * 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"
+
+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,
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-06 11:22:52 +0000