Changes includes;
1. Public API to enable fMP4 and to pass fragment duration.
2. Added `FragmentedMp4Writer`.
3. Added logic to create fragments based on given fragment duration.
4. Write "moov" box only once in the beginning.
3. Add all the required boxes for current implementation.
4. Unit tests for all the new boxes.
5. E2E test for generating fMP4.
Note: The output file is un seek-able with this first implementation.
PiperOrigin-RevId: 594426486
Mp4Muxer does not support out of order B-frames. Currently it
silently writes out of order B-frames, producing an invalid file (with
negative sample durations).
Although `Mp4Extractor` is somehow able to process this invalid file and
`Exoplayer` is able to play it but that is unexpected.
The `sample.mp4` test file contains B frames. Other test files does not
contain `H264 video + AAC audio` format hence created a new test file by
running `sample.mp4` via `Transformer` after applying some effects.
PiperOrigin-RevId: 594016144
With fMP4 implementation there will be two writers `DefaultMp4Writer`
and `FragmentedMp4Writer`.
Changes includes:
1. Make Mp4Writer as an abstract class and keep only common functionality
into it.
2. Create a DefaultMp4Writer which contains existing logic to write MP4.
3. The fMP4 logic needs to access `pending sample buffer info` at various
places, so did refactoring to split List<Pair<BufferInfo, ByteBuffer>>
into two separate lists.
PiperOrigin-RevId: 592861398
Issues with the current implementation
1. The implementation is unnecessarily complicated and can be
easily simplified.To make all the tracks start from the same time,
its only the first sample that require some timestamp adjustments
but the current implementation shifts all the timestamps. Since method
calculates the `sample duration`, shifting all the timestamps has no effect
as such.
2. The implementation always forced first sample to start at 0. But when we
want to use same method for `Fragmented MP4` then it will look inaccurate
as we will call this method for different `fragments` and each `fragment`
will not start from 0 presentation time. Although the output will be same
since this method returns `duration` and not the `timestamps`.
3. As per previous implementation if there is just one sample then
its duration is made equals to its presentation time, which looks incorrect.
With new changes, if a single sample is passed then its duration will always
be 0 irrespective of specified last sample duration behaviour.
PiperOrigin-RevId: 592826612
`Mp4Writer` receives all the tracks/samples and then it adds them to
corresponding `Track` object. As the `Track` object is primarily to hold
track specific data and `Mp4Writer` is responsible for interleaving related
logic, the call to `doInterleave` should be with `Mp4Writer`. The `Track`
object should just act like a data holding class.
This will also help in reusing `Track` class for fragmented MP4 implementation.
PiperOrigin-RevId: 590138002
If we throw away the first keyframe (because it does not contain any bytes to read), we shouldn't behave as if we had written a keyframe to our track. We should instead continue waiting for the first (valid) keyframe.
PiperOrigin-RevId: 554579146
MP4 edit lists sometimes ask to start playback between two samples.
If this happens, we currently change the timestamp of the first
sample to zero to trim it (e.g. to display the first frame for a
slightly shorter period of time). However, we can't do this to audio
samples are they have an inherent duration and trimming them this
way is not possible.
#minor-release
PiperOrigin-RevId: 543420218
*** Original commit ***
Rollback of 65d5132f76
*** Original commit ***
Create InAppMuxer in transformer
To use the InAppMuxer, the client needs to pass InAppMuxer Factory.
***
***
PiperOrigin-RevId: 531470081
*** Original commit ***
Create InAppMuxer in transformer
To use the InAppMuxer, the client needs to pass InAppMuxer Factory.
***
PiperOrigin-RevId: 531056436
The existing logic to drop (actually fail on) 0 sized samples seems no op if
if 2 out of 10 samples are of size 0.
Checked same scenario with MediaMuxer where
1. If input file has 300 samples.
2. Make every 5th sample as an empty byte buffer.
3. Output file is generated without error.
4. Output file has 240 samples.
5. Exoplayer is able to play output file (blurry).
The new change is in line with MediaMuxer behaviour.
PiperOrigin-RevId: 528798046
