| Message ID | 20190203150906.6632-1-liuchh83@gmail.com |
|---|---|
| State | Accepted |
| Commit | aa25198f1b925a464bdfa83a98476f08d26c9209 |
| Headers | show |
On Sun, 3 Feb 2019, Charles Liu wrote: > Binary searching would hang if the fragment items do NOT have timestamp for the specified stream. > > For example, a fmp4 consists of separated 'moof' boxes for each track, and separated 'sidx' for each segment, but no 'mfra' box. > Then every fragment item only have the timestamp for one of its tracks. > > Signed-off-by: Charles Liu <liuchh83@gmail.com> > --- > libavformat/mov.c | 21 ++++++++++++--------- > 1 file changed, 12 insertions(+), 9 deletions(-) > > diff --git a/libavformat/mov.c b/libavformat/mov.c > index 9b9739f788..35cb619e9f 100644 > --- a/libavformat/mov.c > +++ b/libavformat/mov.c > @@ -1266,7 +1266,7 @@ static int64_t get_frag_time(MOVFragmentIndex *frag_index, > static int search_frag_timestamp(MOVFragmentIndex *frag_index, > AVStream *st, int64_t timestamp) > { > - int a, b, m; > + int a, b, m, m0; > int64_t frag_time; > int id = -1; > > @@ -1282,15 +1282,18 @@ static int search_frag_timestamp(MOVFragmentIndex *frag_index, > b = frag_index->nb_items; > > while (b - a > 1) { > - m = (a + b) >> 1; > - frag_time = get_frag_time(frag_index, m, id); > - if (frag_time != AV_NOPTS_VALUE) { > - if (frag_time >= timestamp) > - b = m; > - if (frag_time <= timestamp) > - a = m; > - } > + m0 = m = (a + b) >> 1; > + > + while (m < b && > + (frag_time = get_frag_time(frag_index, m, id)) == AV_NOPTS_VALUE) > + m++; > + > + if (m < b && frag_time <= timestamp) > + a = m; > + else > + b = m0; > } > + > return a; > } > As this fixes a hang, I will push this version soon. Can be optimized later to pure binary search, if anybody is still interested. Regards, Marton
2019-02-10 23:04 GMT+01:00, Marton Balint <cus@passwd.hu>: > > > On Sun, 3 Feb 2019, Charles Liu wrote: > >> Binary searching would hang if the fragment items do NOT have timestamp >> for the specified stream. >> >> For example, a fmp4 consists of separated 'moof' boxes for each track, and >> separated 'sidx' for each segment, but no 'mfra' box. >> Then every fragment item only have the timestamp for one of its tracks. >> >> Signed-off-by: Charles Liu <liuchh83@gmail.com> >> --- >> libavformat/mov.c | 21 ++++++++++++--------- >> 1 file changed, 12 insertions(+), 9 deletions(-) >> >> diff --git a/libavformat/mov.c b/libavformat/mov.c >> index 9b9739f788..35cb619e9f 100644 >> --- a/libavformat/mov.c >> +++ b/libavformat/mov.c >> @@ -1266,7 +1266,7 @@ static int64_t get_frag_time(MOVFragmentIndex >> *frag_index, >> static int search_frag_timestamp(MOVFragmentIndex *frag_index, >> AVStream *st, int64_t timestamp) >> { >> - int a, b, m; >> + int a, b, m, m0; >> int64_t frag_time; >> int id = -1; >> >> @@ -1282,15 +1282,18 @@ static int search_frag_timestamp(MOVFragmentIndex >> *frag_index, >> b = frag_index->nb_items; >> >> while (b - a > 1) { >> - m = (a + b) >> 1; >> - frag_time = get_frag_time(frag_index, m, id); >> - if (frag_time != AV_NOPTS_VALUE) { >> - if (frag_time >= timestamp) >> - b = m; >> - if (frag_time <= timestamp) >> - a = m; >> - } >> + m0 = m = (a + b) >> 1; >> + >> + while (m < b && >> + (frag_time = get_frag_time(frag_index, m, id)) == >> AV_NOPTS_VALUE) >> + m++; >> + >> + if (m < b && frag_time <= timestamp) >> + a = m; >> + else >> + b = m0; >> } >> + >> return a; >> } >> > > As this fixes a hang, I will push this version soon. Please mention ticket #7572 in the commit message. Thank you, Carl Eugen
It is lucky that my patch works to ticket 7572. However, #7572 has a deeper reason. Mov demuxer consider that fragmented index is completed if a ‘sidx’ point to the end of the file. But there may be other ‘sidx’ for other tracks. If we skip the tail from there, we will missing the last ‘sidx’ and ‘moof’. Then AV_NOPTS_VALUE occurs. I tried to avoid skipping the tail simply. However, fate-test run failed on mov-frag-encrypted.mp4. BTW, I just got back from vacation. I am willing to follow an optimized solution. Thanks and Regards, Chenhui Carl Eugen Hoyos <ceffmpeg@gmail.com> 于2019年2月11日周一 上午6:24写道： > 2019-02-10 23:04 GMT+01:00, Marton Balint <cus@passwd.hu>: > > > > > > On Sun, 3 Feb 2019, Charles Liu wrote: > > > >> Binary searching would hang if the fragment items do NOT have timestamp > >> for the specified stream. > >> > >> For example, a fmp4 consists of separated 'moof' boxes for each track, > and > >> separated 'sidx' for each segment, but no 'mfra' box. > >> Then every fragment item only have the timestamp for one of its tracks. > >> > >> Signed-off-by: Charles Liu <liuchh83@gmail.com> > >> --- > >> libavformat/mov.c | 21 ++++++++++++--------- > >> 1 file changed, 12 insertions(+), 9 deletions(-) > >> > >> diff --git a/libavformat/mov.c b/libavformat/mov.c > >> index 9b9739f788..35cb619e9f 100644 > >> --- a/libavformat/mov.c > >> +++ b/libavformat/mov.c > >> @@ -1266,7 +1266,7 @@ static int64_t get_frag_time(MOVFragmentIndex > >> *frag_index, > >> static int search_frag_timestamp(MOVFragmentIndex *frag_index, > >> AVStream *st, int64_t timestamp) > >> { > >> - int a, b, m; > >> + int a, b, m, m0; > >> int64_t frag_time; > >> int id = -1; > >> > >> @@ -1282,15 +1282,18 @@ static int > search_frag_timestamp(MOVFragmentIndex > >> *frag_index, > >> b = frag_index->nb_items; > >> > >> while (b - a > 1) { > >> - m = (a + b) >> 1; > >> - frag_time = get_frag_time(frag_index, m, id); > >> - if (frag_time != AV_NOPTS_VALUE) { > >> - if (frag_time >= timestamp) > >> - b = m; > >> - if (frag_time <= timestamp) > >> - a = m; > >> - } > >> + m0 = m = (a + b) >> 1; > >> + > >> + while (m < b && > >> + (frag_time = get_frag_time(frag_index, m, id)) == > >> AV_NOPTS_VALUE) > >> + m++; > >> + > >> + if (m < b && frag_time <= timestamp) > >> + a = m; > >> + else > >> + b = m0; > >> } > >> + > >> return a; > >> } > >> > > > > As this fixes a hang, I will push this version soon. > > Please mention ticket #7572 in the commit message. > > Thank you, Carl Eugen > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel >
On Sun, 10 Feb 2019, Carl Eugen Hoyos wrote: > 2019-02-10 23:04 GMT+01:00, Marton Balint <cus@passwd.hu>: >> >> >> On Sun, 3 Feb 2019, Charles Liu wrote: >> >>> Binary searching would hang if the fragment items do NOT have timestamp >>> for the specified stream. >>> >>> For example, a fmp4 consists of separated 'moof' boxes for each track, and >>> separated 'sidx' for each segment, but no 'mfra' box. >>> Then every fragment item only have the timestamp for one of its tracks. >>> >>> Signed-off-by: Charles Liu <liuchh83@gmail.com> >>> --- >>> libavformat/mov.c | 21 ++++++++++++--------- >>> 1 file changed, 12 insertions(+), 9 deletions(-) >>> >>> diff --git a/libavformat/mov.c b/libavformat/mov.c >>> index 9b9739f788..35cb619e9f 100644 >>> --- a/libavformat/mov.c >>> +++ b/libavformat/mov.c >>> @@ -1266,7 +1266,7 @@ static int64_t get_frag_time(MOVFragmentIndex >>> *frag_index, >>> static int search_frag_timestamp(MOVFragmentIndex *frag_index, >>> AVStream *st, int64_t timestamp) >>> { >>> - int a, b, m; >>> + int a, b, m, m0; >>> int64_t frag_time; >>> int id = -1; >>> >>> @@ -1282,15 +1282,18 @@ static int search_frag_timestamp(MOVFragmentIndex >>> *frag_index, >>> b = frag_index->nb_items; >>> >>> while (b - a > 1) { >>> - m = (a + b) >> 1; >>> - frag_time = get_frag_time(frag_index, m, id); >>> - if (frag_time != AV_NOPTS_VALUE) { >>> - if (frag_time >= timestamp) >>> - b = m; >>> - if (frag_time <= timestamp) >>> - a = m; >>> - } >>> + m0 = m = (a + b) >> 1; >>> + >>> + while (m < b && >>> + (frag_time = get_frag_time(frag_index, m, id)) == >>> AV_NOPTS_VALUE) >>> + m++; >>> + >>> + if (m < b && frag_time <= timestamp) >>> + a = m; >>> + else >>> + b = m0; >>> } >>> + >>> return a; >>> } >>> >> >> As this fixes a hang, I will push this version soon. > > Please mention ticket #7572 in the commit message. Sure. Pushed. Regards, Marton
diff --git a/libavformat/mov.c b/libavformat/mov.c index 9b9739f788..35cb619e9f 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -1266,7 +1266,7 @@ static int64_t get_frag_time(MOVFragmentIndex *frag_index, static int search_frag_timestamp(MOVFragmentIndex *frag_index, AVStream *st, int64_t timestamp) { - int a, b, m; + int a, b, m, m0; int64_t frag_time; int id = -1; @@ -1282,15 +1282,18 @@ static int search_frag_timestamp(MOVFragmentIndex *frag_index, b = frag_index->nb_items; while (b - a > 1) { - m = (a + b) >> 1; - frag_time = get_frag_time(frag_index, m, id); - if (frag_time != AV_NOPTS_VALUE) { - if (frag_time >= timestamp) - b = m; - if (frag_time <= timestamp) - a = m; - } + m0 = m = (a + b) >> 1; + + while (m < b && + (frag_time = get_frag_time(frag_index, m, id)) == AV_NOPTS_VALUE) + m++; + + if (m < b && frag_time <= timestamp) + a = m; + else + b = m0; } + return a; }
Binary searching would hang if the fragment items do NOT have timestamp for the specified stream. For example, a fmp4 consists of separated 'moof' boxes for each track, and separated 'sidx' for each segment, but no 'mfra' box. Then every fragment item only have the timestamp for one of its tracks. Signed-off-by: Charles Liu <liuchh83@gmail.com> --- libavformat/mov.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-)