Commit Graph

25 Commits

Author SHA1 Message Date
Samidh 4686454a73
Add segment_list support for DASH on-demand profile
Configurable under flag --dash_force_segment_list, default to false.

Note that DASH live profile is not supported right now.
2021-05-25 12:08:58 -07:00
Jacob Trimble 26334f2808 Refactor XmlNode and libxml usages.
- Use std::move to transfer ownership.
- Avoid libxml primitives outside XmlNode.
- Have attribute setting return errors.
- Mark bool returns with WARN_UNUSED_RESULTS and use return value.
- Use std::string over char*.

Change-Id: Ia00bb29c690025275e270f10e5c065722481c0c5
2020-11-16 14:35:37 -08:00
KongQun Yang a86a697d8d Add more loggings for GAPs
Fixes #474.

Change-Id: I32f097c8a0e8d3381a276e6a130cb888e3ddd7f6
2019-09-11 00:02:52 +00:00
KongQun Yang 3c26dfbd53 Estimate target duration in bandwidth calculation from initial blocks
We used to use the target segment duration provided by the user.
Unfortunately that does not work for iframe only playlist which
the target duration is effectively equal to the GOP duration.

In the new approach, we estimate the target duration from the initial
few blocks (10 blocks right now).

Fixes #610.

Change-Id: Ie8bf943e157149ca7ed3b9382fe0a1088d0774e2
2019-07-11 17:45:55 -07:00
KongQun Yang b85e5c9368 Use segment duration in buffer depth calculation
Segment start,end time was used previously, which could result in
problems if there are discontinuity in the streams. E.g. if the
stream has timestamp, 10000, 10001, 10002 and then next segment
comes in with timestamp 1. With the previous logic, all the segments
would remain in the time shift buffer until after 10000 segments
even with a small time shift buffer depth of 10.

This could also happen when timestamp wraps around, which could
happen during long time of live streaming.

This change will also be useful to support multi-period live DASH.

Fixes #563.

Change-Id: Ie078d76c6e4af13ade9ad46191c8e3529069ed4d
2019-04-17 22:47:10 +00:00
KongQun Yang 6d6db76c80 Retry file deletion if it fails
The file deletion could fail if it is still held by the web server.

This CL adds retry logic to retry the deletion.

Closes #533.

Change-Id: Ib42ed8db11f32897a29e3b58c1be89d05f5dd034
2019-01-02 15:23:27 -08:00
KongQun Yang 74df8d30cc Exclude short segments from peak bandwidth computation
https://tools.ietf.org/html/rfc8216#section-4.1
The peak segment bit rate of a Media Playlist is the largest bit rate
of any contiguous set of segments whose total duration is between 0.5
and 1.5 times the target duration.

Fixes #498.

Change-Id: I1f28972b9cc5977735e47906bdcd88ba3942db5a
2018-11-26 20:02:09 +00:00
KongQun Yang 5dd21179ec Do not use harmonic mean in bandwidth calculation
Instead, caclulating average bandwidth by dividing the sum of the
sizes of every segment by the sum of the durations of every segment.
This aligns with the requirement in HLS spec:
https://tools.ietf.org/html/draft-pantos-http-live-streaming-23 4.1.

BandwidthEstimator is also simplified to handle all blocks only.

Fixes #361

Change-Id: I89e7d415a841f4d4048f199de8dae7ffa250467b
2018-07-12 10:46:47 -07:00
KongQun Yang f21d93dd65 Clean up difference comparison in representation.cc
Change-Id: Ibde83d1b8b2f644899f93790978d906dba5d4c14
2018-07-02 17:48:17 +00:00
KongQun Yang b4256bf040 [Cleanup] Use int64_t for time for consistency
Change-Id: I408f3fe7c98320be4e43ca2a5bcb9b22cc8a2012
2018-06-29 22:53:06 +00:00
KongQun Yang 418e741f7f [DASH] Fix potential text Segment Timeline not grouped
This happens when --allow_approximate_segment_timeline_ is set.

Fixes #417.

Change-Id: Idf938ad4e0f7788a00c7485b7eeda43358a94178
2018-06-22 00:45:00 +00:00
KongQun Yang 192ef2a0ac Update MuxerListeners to support multiple OnMediaStart/End
This is needed to support one file per representation per period where
there will be multiple content files generated.

Issue: #384

Change-Id: Ib7af750edf864d99075b8da4f3640217a5a94302
2018-05-25 20:43:34 +00:00
KongQun Yang 37d4ff017f Support removing segments outside of live window in HLS
Issue: #223

Change-Id: Ib91c60268d8df9adbaf5f6cac77eaebd6a3edb6e
2018-04-30 17:25:39 -07:00
KongQun Yang 224b597b48 Support approximate SegmentTimeline
It is not always possible to align segment duration to target duration
exactly. For example, for AAC with sampling rate of 44100, there are
always 1024 audio frames per sample, so the sample duration is
1024/44100. For a target duration of 2 seconds, the closest segment
duration would be 1.984 or 2.00533.

This feature allows MPD generator to treat these segments as having
the same duration, thus allows MPD generator to generate less
SegmentTimeline entries and potentially no SegmentTimeline entries
(replaced with SegmentTemplate@duration instead if
  --segment_template_constant_duration flag is enabled).

Under flag --allow_approximate_segment_timeline. Disabled by default.

Fixes #330.

Change-Id: I5044eaa348ebbf45bf792a2af53fc95a115ae21b
2018-04-30 17:15:47 -07:00
KongQun Yang b2932d5a33 Fix bitrate for DASH on-demand profile too
Removed the logic in MuxerListener to estimate bandwidth from file
size and duration, since it is not compliant to the spec.

MpdBuilder will estimate bandwidth from segment size and duration
if bandwidth is not specified in MediaInfo.

Here is the statement from DASH spec (23009-1:2014):

Consider a hypothetical constant bitrate channel of
bandwidth with the value of this attribute in bits per second
(bps). Then, if the Representation is continuously delivered
at this bitrate, starting at any SAP that is indicated either by
@startwithsap or by any Segment Index box, a client can
be assured of having enough data for continuous playout
providing playout begins after @minbuffertime *
@bandwidth bits have been received (i.e. at time
@minbuffertime after the first bit is received).
For dependent Representations this value specifies the
bandwidth according to the above definition for the
aggregation of this Representation and all complementary
Representations.

Fixes #376.

Change-Id: I0fddce39e709d0cded0a4c9ae59adbbcc97ec5ea
2018-04-24 23:25:02 +00:00
KongQun Yang 43be3c8e8b Use max bitrate in Representation@bandwidth instead of average bitrate
According to DASH spec (23009-1:2014):

Consider a hypothetical constant bitrate channel of
bandwidth with the value of this attribute in bits per second
(bps). Then, if the Representation is continuously delivered
at this bitrate, starting at any SAP that is indicated either by
@startwithsap or by any Segment Index box, a client can
be assured of having enough data for continuous playout
providing playout begins after @minbuffertime *
@bandwidth bits have been received (i.e. at time
@minbuffertime after the first bit is received).
For dependent Representations this value specifies the
bandwidth according to the above definition for the
aggregation of this Representation and all complementary
Representations.

This suggests that max bitrate should be used instead of average
bitrate.

Also cleaned up BandwidthEstimator code.

Fixes #376.

Change-Id: Ibf5896394c5c6bb820849771a2129c59202d2273
2018-04-17 22:39:58 +00:00
KongQun Yang 64c2ad7d6e Support removing segments outside of live window in DASH
Issue: #223

Change-Id: Ie2d98a8f1553862532f1bdd074ca022d8904f0ea
2018-04-13 14:15:58 -07:00
KongQun Yang 4549b1d569 Remove pto_adjustment flag
This flag was introduced to workaround a rounding error in Chrome
(probably in other browsers too).

Also although this flag avoids the first frame of a Period to be
dropped due to rounding error but it could cause the last frame of a
Period to be dropped.

Now that we use a high precision Period@duration, we do not expect to
see rounding errors any more. The player would be a better place for
the workaround even if it is still needed.

Related issue: #368.

Change-Id: I3bd517ecc6d548ff62e0c13394edb49d4bc68e8f
2018-04-13 20:07:47 +00:00
KongQun Yang ee9b7f6392 Calculate presentationTimeOffset and Period@duration from segments
Prefer timestamps from Video AdaptationSets if available - this avoids
possible video playback jitters due to gaps.

presentationTimeOffset is not applied to the first period as it may in
negative dts which Chrome does not like: https://crbug.com/398141.

It is safe to apply to subsequent periods as the actual offset applied
takes Period@start into consideration:

    offset = Period@start - presentationTimeOffset

The result timestamp with offset applied is close to Period@start, so
it is unlikely to result in a negative dts value.

Closes b/73899306.

Change-Id: If8361f5469610093b3aac6675754536ad7e83c4c
2018-03-01 08:55:10 -08:00
Aaron Vaage 30b5fdf19f Add Text Codec To Codec String
This change has the hls master playlist add the text codec string
to the list of codecs in a variant.

Bug: 72942756

Change-Id: Ib25bb2064a291d10d7b1d261a4307991df62220c
2018-02-28 19:23:36 +00:00
KongQun Yang 221ac81772 Prefer Period@duration for static MPD with >1 periods
It is easier to insert Ad Periods with Period@duration compared to
Period@start.

Change-Id: Ib52e81612562bf60b0e0513a09d9a31c42b09604
2018-02-07 01:13:28 +00:00
KongQun Yang d76ccea46f [DASH] Support multiple period
Change-Id: Ifd17bf0eabbd61ec7a1d35f0b864b5aa6666aa87
2018-01-11 21:44:18 +00:00
KongQun Yang ef2c424876 Implement Representation::GetDurationSeconds
Also added Period::GetAdaptationSets and
AdaptationSet::GetRepresentations.

Instead of implementing GetDurationSeconds in all MpdBuilder classes
(MpdBuilder/Period/Adaptation/Representation) like what we used to do
with GetEarliestTimestamp, the two new functions allows MpdBuilder to
iterate through the Representations to get durations.

Also updates GetEarliestTimestamp functions to use the same iteration
method.

Change-Id: I682b70c07c248c0f6511ec3d9019086f986ee10e
2018-01-09 01:03:05 +00:00
KongQun Yang 718fce068d Refactor DashIopMpdNotifier Part 2
Move AdaptationSet related functions to the new Period class, which
maps to <Period> element and provides methods to add AdaptationSets.

Change-Id: I0fee290769fbe9a6355cc1b8c86baec8fbc4b4fd
2017-12-22 13:24:38 -08:00
KongQun Yang 86d960bea6 Move AdaptationSet, Representation out of mpd_builder.h
Change-Id: I61fffb4d956f189b44c7537ddcf183bbf4129840
2017-12-14 21:28:06 +00:00