Currently, if the movie source filter is used and a seek_point is
specified on a file that has a negative start time, ffmpeg will fail.
An easy way to reproduce this is as follows:
$ ffmpeg -vsync passthrough -filter_complex 'color=d=10,setpts=PTS-1/TB'
test.mp4
$ ffmpeg -filter_complex 'movie=filename=test.mp4:seek_point=2' -f null -
The problem is caused by checking for int64_t overflow the wrong way.
In general, to check whether a + b overflows, it is not enough to do:
a > INT64_MAX - b
because b might be negative; the correct way is:
b > 0 && > a > INT64_MAX - b
---
libavfilter/src_movie.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libavfilter/src_movie.c b/libavfilter/src_movie.c
index 82d2bcd..eab2458 100644
--- a/libavfilter/src_movie.c
+++ b/libavfilter/src_movie.c
@@ -240,7 +240,7 @@ static av_cold int movie_common_init(AVFilterContext *ctx)
timestamp = movie->seek_point;
// add the stream start time, should it exist
if (movie->format_ctx->start_time != AV_NOPTS_VALUE) {
- if (timestamp > INT64_MAX - movie->format_ctx->start_time) {
+ if (timestamp > 0 && movie->format_ctx->start_time > INT64_MAX -
timestamp) {
av_log(ctx, AV_LOG_ERROR,
"%s: seek value overflow with start_time:%"PRId64"
seek_point:%"PRId64"\n",
movie->file_name, movie->format_ctx->start_time,
movie->seek_point);
--
2.8.0
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
