Commit Graph

8 Commits

Author SHA1 Message Date
KongQun Yang 19f80d8478 Put namespace URIs in DASH mpd only if needed
Change-Id: I31284b665599a8ee8f0b1aa11b58d6797dbe2884
2018-09-25 15:45:48 -07:00
KongQun Yang 40ea1286b9 Add support for EditLists in ISO-BMFF
- EditLists in input files are parsed and applied to sample timestamps.
- An EditList will be inserted in the ISO-BMFF output if
  - There is an offset between the initial presentation timestamp (pts)
    and decoding timestamp (dts). Chrome, as of M67, still uses dts in
    buffered range API [1], which creates various problems when buffered
    range by pts does not align with buffered range by dts. There is
    another bug in Chrome that applies EditList to pts only [2]. This
    means that we can insert an EditList to align pts range and dts range.
  - MediaSamples have negative timestamps (e.g. for Audio Priming).

You may notice the below change on some contents:
- Some media duration is reduced by one or two frames. This is because
  EditList in the input file was ignored in the previous code, so video
  streams start with a zero dts and a non-zero pts; the smaller of dts
  and pts was used as the starting timestamp (related to the earlier
  workaround for Chrome's dts bug), so the calculated duration was
  actually a bit larger than the actual duration. Now with EditList
  applied, the initial pts is reduced to zero, so the media duration is
  also reduced to reflect the actual and correct media duration.

It may also result in negative timestamps in TS/HLS Packed Audio, which
will be addressed in a follow up CL.

Fixes #112.
Partially address b/110782437.

[1] https://crbug.com/718641, fixed but behind MseBufferByPts.
[2] https://crbug.com/354518. Chrome is planning to enable the fix for
    [1] before addressing this bug, so we are safe.

Change-Id: I59317740ad3807ca66fa74b3a18fdf7f32c96aeb
2018-07-26 23:20:21 +00:00
KongQun Yang 4d8ce0ff5d Extract bitrates in ES descriptor for AAC if available
Change-Id: I1aa53b519e8751400bea6b33936cb2e7a05958dc
2018-05-22 11:59:58 -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 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 631bbdc883 Update Encrypted Tests to Use DiffDir
This changes almost all encrypted tests to use DiffDir. The remaining
un-updated tests are tests that won't match every time.

Change-Id: I858bbaa0beea34887cc3100eb784aa2aecd5a0a5
2018-03-13 16:37:10 +00:00