Commit Graph

8 Commits

Author SHA1 Message Date
KongQun Yang f49b89280c Support STYLE and REGION in WebVTT
Note that STYLE and REGION are not supported in mp4 container due to
spec limitation as 14496-30:2014 does not specify a way to signal
styles/regions inside mp4.

Closes #344.

Change-Id: I05c14df916f7b2c7ca4364ee9407e0eda4dc7a3f
2018-08-20 14:12:07 -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 71072d4e6d Combine some DASH/HLS tests into one
This saves some testing time and also make it easier to compare
DASH and HLS test results.

Change-Id: Ia4bdb39f1f5ef7ee7b3f8f37f83d7490109380c2
2018-07-16 14:59:16 -07:00
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 99a2ad03af [HLS] Support AVERAGE-BANDWIDTH
Issue #361

Change-Id: Id8eb8283675cba5ec7234d13c4ac235f34e3bec9
2018-07-12 10:43:49 -07:00
KongQun Yang 6b4a75b6ba Changed to use BandwidthEstimator in MediaPlaylist
Preparing for addressing #361.

Change-Id: I4b2e834948e681bc790efc61b63a24d44f70015d
2018-06-22 11:12:23 -07:00
Aaron Vaage d8830e3168 Remove "wvtt" from Master Playlist Codec String
Having "wvtt" in the codec string (in the master playlist) causes
errors on some older Apple products. As including it is optional,
we are opted to omit it to ensure support for all Apple products.

Close #402

Change-Id: Ib1072bcc26a3ff66e3a6d3204789c0c8c678d4db
2018-06-20 17:31:51 +00:00
Aaron Vaage b9dee56294 Rebuild Text WebVtt to MP4 WebVtt
The previous text to mp4 webvtt pipeline was incomplete. It
did not insert ad cues and it could only insert a segment
after a sample ended.

Now the pipeline supports ad cue insert and segment insertion
mid text sample. This required the pipeline to use the text
chunker (to split samples and insert segments) and required
a major overhaul of the text to mp4 converter.

Before the converter came before the chunker. This meant that
the converter only expected to see stream info and text samples.
Moving the converter after the cue aligner and chunker means
that the convert had to be aware of segments and cues.

The general approach is the same, however the converter will
convert the samples per-segment as the chunker will introduce
duplicate samples if a sample spans across segments.

Closes #362
Closes #382

Change-Id: I0f54a40524c36a602ad3804a0da26e80851c92fd
2018-06-01 19:49:56 +00:00