avi: Improve non-interleaved detection

Additional fixes by Nigel Touati-Evans <nigel.touatievans@gmail.com>.

Check the index for streams with a time drift of 2s or a buffer drift
of 64MB.

Bug-Id: 666
CC: libav-stable@libav.org
Sample-Id: yet-another-broken-interleaved-avi.avi

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Signed-off-by: Diego Biurrun <diego@biurrun.de>
This commit is contained in:
Michael Niedermayer 2014-04-02 09:11:10 +02:00 committed by Diego Biurrun
parent 0ca0924c10
commit 9d599e3f6e

View File

@ -795,7 +795,11 @@ fail:
if (!avi->index_loaded && pb->seekable)
avi_load_index(s);
avi->index_loaded = 1;
avi->non_interleaved |= guess_ni_flag(s);
if ((ret = guess_ni_flag(s)) < 0)
return ret;
avi->non_interleaved |= ret;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
if (st->nb_index_entries)
@ -1307,6 +1311,64 @@ static int avi_read_idx1(AVFormatContext *s, int size)
return 0;
}
/* Scan the index and consider any file with streams more than
* 2 seconds or 64MB apart non-interleaved. */
static int check_stream_max_drift(AVFormatContext *s)
{
int64_t min_pos, pos;
int i;
int *idx = av_mallocz_array(s->nb_streams, sizeof(*idx));
if (!idx)
return AVERROR(ENOMEM);
for (min_pos = pos = 0; min_pos != INT64_MAX; pos = min_pos + 1LU) {
int64_t max_dts = INT64_MIN / 2;
int64_t min_dts = INT64_MAX / 2;
int64_t max_buffer = 0;
min_pos = INT64_MAX;
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
int n = st->nb_index_entries;
while (idx[i] < n && st->index_entries[idx[i]].pos < pos)
idx[i]++;
if (idx[i] < n) {
int64_t dts;
dts = av_rescale_q(st->index_entries[idx[i]].timestamp /
FFMAX(ast->sample_size, 1),
st->time_base, AV_TIME_BASE_Q);
min_dts = FFMIN(min_dts, dts);
min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
}
}
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
if (idx[i] && min_dts != INT64_MAX / 2) {
int64_t dts;
dts = av_rescale_q(st->index_entries[idx[i] - 1].timestamp /
FFMAX(ast->sample_size, 1),
st->time_base, AV_TIME_BASE_Q);
max_dts = FFMAX(max_dts, dts);
max_buffer = FFMAX(max_buffer,
av_rescale(dts - min_dts,
st->codec->bit_rate,
AV_TIME_BASE));
}
}
if (max_dts - min_dts > 2 * AV_TIME_BASE ||
max_buffer > 1024 * 1024 * 8 * 8) {
av_free(idx);
return 1;
}
}
av_free(idx);
return 0;
}
static int guess_ni_flag(AVFormatContext *s)
{
int i;
@ -1336,7 +1398,11 @@ 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;
return check_stream_max_drift(s);
}
static int avi_load_index(AVFormatContext *s)