Commit Graph

8 Commits

Author SHA1 Message Date
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 772aa7c93f Do not force earliest_presentation_time to 0 for VOD
Instead, the actual earliest presentation time is used except for
the first segment if there is an offset between presentation time
(pts) and decoding time (dts).

Chrome (as of v66) reports dts instead of pts in buffered ranges in
MSE API. To avoid breaking Chrome, the earliest_presentation_time
of the first segment is set to its dts as Chrome does not like negative
values for
  adjusted dts = dts + Period@start (0 for the first period)
                 - presentationTimeOffset (earliest_presentation_time).

Fixes #303.

Change-Id: I5ca80e05d5570961400499436f2bcc01f06e69e0
2018-04-09 18:39:15 +00:00
KongQun Yang 634ee65663 Generate a more accurate time in Period@duration
Chrome internally uses time accurate to microseconds, which is
implemented per MSE spec (https://www.w3.org/TR/media-source/).

Generate Period@duration with better precision to avoid possible
buffered range gaps in Chrome (possibly other browsers too), which
may lead to other problems like playback stall.

b/74238961
Fixes #368.

Change-Id: I357a0f62b67f75c7ca044bb99ea4e3c8bbb6fecd
2018-04-03 21:42:33 +00:00
KongQun Yang 4e57259d2a Integrate CueAlignmentHandler
Also changed ChunkingHandler to be one-one handler.

Issue: #355

Change-Id: Ie98a96bcc0ddded347699c9f333f604826976d11
2018-03-26 17:58:30 +00:00
Aaron Vaage b2ce6322b6 Remove Test File Index in packager_test.py
Instead of using the test file's index in a list to create the output
name, use the original filename and the descriptor.

This caused some problems with file name collisions when some tests
were using the same name. That was fixed by changing the names. This
will go away once they are transitioned to use DiffDir like the other
tests.

Change-Id: I0a4c480406705ca63fcea61c86c67d4a5f739295
2018-03-06 21:38:04 +00:00
KongQun Yang b24a95b1aa Rewrite init segment in MultiSegmentSegmenter::DoFinalize
This is called when reaching end of the file of the media. The duration
of the media is updated.

Fixes #340.

Change-Id: I446f2d341b02125d4a7d8c958bda269b5403cb9c
2018-03-05 14:25:08 -08:00
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 c7929b1505 Remove "with" from test names
Remove the leading "with" from test directories.

Bug: 73830478
Change-Id: I45a0914b5a0e56ec9d3340ec81eb5048c1d653a3
2018-02-27 17:43:16 -08:00