avidec: better NI detection.

The new code detects NI avis by analyzing the index.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2012-04-01 09:49:32 +02:00
parent 7c9d69360c
commit 8df774be88
1 changed files with 28 additions and 1 deletions

View File

@ -1292,6 +1292,8 @@ static int guess_ni_flag(AVFormatContext *s){
int64_t last_start=0;
int64_t first_end= INT64_MAX;
int64_t oldpos= avio_tell(s->pb);
int *idx;
int64_t min_pos, pos;
for(i=0; i<s->nb_streams; i++){
AVStream *st = s->streams[i];
@ -1315,7 +1317,32 @@ static int guess_ni_flag(AVFormatContext *s){
first_end= st->index_entries[n-1].pos;
}
avio_seek(s->pb, oldpos, SEEK_SET);
return last_start > first_end;
if (last_start > first_end)
return 1;
idx= av_mallocz(sizeof(*idx) * s->nb_streams);
for (min_pos=pos=0; min_pos!=INT64_MAX; pos= min_pos+1) {
int64_t max_dts = INT64_MIN/2, min_dts= INT64_MAX/2;
min_pos = INT64_MAX;
for (i=0; i<s->nb_streams; i++) {
AVStream *st = s->streams[i];
int n= st->nb_index_entries;
while (idx[i]<n && st->index_entries[idx[i]].pos < pos)
idx[i]++;
if (idx[i] < n) {
min_dts = FFMIN(min_dts, av_rescale_q(st->index_entries[idx[i]].timestamp, st->time_base, AV_TIME_BASE_Q));
min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
}
if (idx[i])
max_dts = FFMAX(max_dts, av_rescale_q(st->index_entries[idx[i]-1].timestamp, st->time_base, AV_TIME_BASE_Q));
}
if(max_dts - min_dts > 2*AV_TIME_BASE) {
av_free(idx);
return 1;
}
}
av_free(idx);
return 0;
}
static int avi_load_index(AVFormatContext *s)