ffmpeg: Add threshold to discard crazy/damaged timestamps.

The added tests are limited to the case where timestamp discontinuities
are not allowed. The default is 30 hours which is arbitrarily picked and
quite conservative.
This prevents a out of memory condition due to duplicating a frame
millions of times.

Found-by:  Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2012-02-07 23:43:10 +01:00
parent 789d6b73cf
commit 29034e6503

View File

@ -171,6 +171,7 @@ static int nb_frames_drop = 0;
static int input_sync;
static float dts_delta_threshold = 10;
static float dts_error_threshold = 3600*30;
static int print_stats = 1;
@ -3020,14 +3021,14 @@ static int transcode(OutputFile *output_files, int nb_output_files,
// ist->next_dts,
// ist->dts, av_rescale_q(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q), input_files[ist->file_index].ts_offset,
// ist->st->codec->codec_type);
if (pkt.dts != AV_NOPTS_VALUE && ist->next_dts != AV_NOPTS_VALUE
&& (is->iformat->flags & AVFMT_TS_DISCONT)) {
if (pkt.dts != AV_NOPTS_VALUE && ist->next_dts != AV_NOPTS_VALUE && !copy_ts) {
int64_t pkt_dts = av_rescale_q(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q);
int64_t delta = pkt_dts - ist->next_dts;
if((delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
if (is->iformat->flags & AVFMT_TS_DISCONT) {
if(delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
(delta > 1LL*dts_delta_threshold*AV_TIME_BASE &&
ist->st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE) ||
pkt_dts+1<ist->pts)&& !copy_ts){
pkt_dts+1<ist->pts){
input_files[ist->file_index].ts_offset -= delta;
av_log(NULL, AV_LOG_DEBUG,
"timestamp discontinuity %"PRId64", new offset= %"PRId64"\n",
@ -3036,6 +3037,23 @@ static int transcode(OutputFile *output_files, int nb_output_files,
if (pkt.pts != AV_NOPTS_VALUE)
pkt.pts-= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
}
} else {
if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
(delta > 1LL*dts_error_threshold*AV_TIME_BASE && ist->st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE) ||
pkt_dts+1<ist->pts){
av_log(NULL, AV_LOG_WARNING, "DTS %"PRId64", next:%"PRId64" st:%d invalid droping\n", pkt.dts, ist->next_dts, pkt.stream_index);
pkt.dts = AV_NOPTS_VALUE;
}
if (pkt.pts != AV_NOPTS_VALUE){
int64_t pkt_pts = av_rescale_q(pkt.pts, ist->st->time_base, AV_TIME_BASE_Q);
delta = pkt_pts - ist->next_dts;
if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
(delta > 1LL*dts_error_threshold*AV_TIME_BASE && ist->st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE)) {
av_log(NULL, AV_LOG_WARNING, "PTS %"PRId64", next:%"PRId64" invalid droping st:%d\n", pkt.pts, ist->next_dts, pkt.stream_index);
pkt.pts = AV_NOPTS_VALUE;
}
}
}
}
// fprintf(stderr,"read #%d.%d size=%d\n", ist->file_index, ist->st->index, pkt.size);
@ -4960,6 +4978,7 @@ static const OptionDef options[] = {
{ "copytb", HAS_ARG | OPT_INT | OPT_EXPERT, {(void*)&copy_tb}, "copy input stream time base when stream copying", "source" },
{ "shortest", OPT_BOOL | OPT_EXPERT, {(void*)&opt_shortest}, "finish encoding within shortest input" }, //
{ "dts_delta_threshold", HAS_ARG | OPT_FLOAT | OPT_EXPERT, {(void*)&dts_delta_threshold}, "timestamp discontinuity delta threshold", "threshold" },
{ "dts_error_threshold", HAS_ARG | OPT_FLOAT | OPT_EXPERT, {(void*)&dts_error_threshold}, "timestamp error delta threshold", "threshold" },
{ "xerror", OPT_BOOL, {(void*)&exit_on_error}, "exit on error", "error" },
{ "copyinkf", OPT_BOOL | OPT_EXPERT | OPT_SPEC, {.off = OFFSET(copy_initial_nonkeyframes)}, "copy initial non-keyframes" },
{ "frames", OPT_INT64 | HAS_ARG | OPT_SPEC, {.off = OFFSET(max_frames)}, "set the number of frames to record", "number" },