This is done by reserving some space for moov box at the start of the file and writing it there if it fits. If it doesn't fit, then it is written at the end of the file.
PiperOrigin-RevId: 643944698
Muxer never uses latest output position but always writes to
a specific location, so restoring its position does not add any
value.
PiperOrigin-RevId: 642996941
Add composition time offset parameter to TRUN box to
support muxing of videos containing B-frames by FragmentedMp4Muxer.
Update TRUN box version from 0 to 1 in order to manage signed
composition time offset.
PiperOrigin-RevId: 636426397
Add ctts box implementation to handle muxing B-frame videos.
Add method convertPresentationTimestampsToCompositionOffset to
provide sample offsets. Return empty ctts box in case of video
does not contain B-frame. Add ctts box to MoovStructure to handle
muxing the video containing B-frames.
PiperOrigin-RevId: 633537106
The keys and ilst boxes in the MP4 muxer were allocated
with a fixed size of 200 bytes. This was not enough to
store the keys and values of large metadata entries, which
could cause the muxer to throw an exception. This CL allocates
the correct size for the keys and ilst boxes based on the size of the metadata entries.
PiperOrigin-RevId: 630331680
Add ctts box implementation to handle muxing B-frame videos.
Add method convertPresentationTimestampsToCompositionOffset to
provide sample offsets. Return empty ctts box in case of video
does not contain B-frame. Add ctts box to MoovStructure to handle
muxing the video containing B-frames.
PiperOrigin-RevId: 628346257
Update the function convertPresentationTimestampsToDurationsVu
to return a list of duration in decoding order,used in the
creation of STTS boxes.
PiperOrigin-RevId: 627052898
Since the public class has already been split into `Mp4Muxer` and
`FragmentedMp4Muxer`, there is no need for having common interface
for internal implementation.
In the follow up CL `BasicMp4Writer` will be renamed to `Mp4Writer`
which is more appropriate and aligns with public class names.
PiperOrigin-RevId: 619486876
This CL aims to separate Fragmented MP4 related logic in a separate public class.
Earlier all the logic was in a single class `Mp4Muxer`.
PiperOrigin-RevId: 619206661
The immediate plan is to replace `Transformer Muxer interface`
with this one.
It was not straight forward to move/change `Transformer Muxer interface`
hence this intermediate step.
The follow up CL will also remove fragmented MP4 related code from
`Mp4Muxer` and move it into `FragmentedMp4Muxer implements Muxer`.
PiperOrigin-RevId: 618789265
Issue: androidx/media#725
Ideally the test to transmux a `ts` file (having 3 bytes NAL start code)
should go into `Mp4MuxerEndToEndTest`but `Mp4MuxerEndToEndTest` uses `MediaExtractor` and `MediaExtractor` is returning samples with `4 byte NAL start code` which will not exercise the newly added code path.
Hence the test is added in `TransformerWithInAppMuxerEndToEndTest` which
internally uses `media3 extractor` and feeds samples with `3 bytes NAL start code`
only.
PiperOrigin-RevId: 617985866
This refactoring is required to support 3 byte NAL start code, in which
the sample ByteBuffer might change after AnnexB to Avcc conversion.
This would required changes in the corresponding BufferInfo as well.
PiperOrigin-RevId: 617538338
The AV1 video stream does not contain NAL unit which is a concept
specific to H.264/H.265.
This was not caught before muxer does an in place replacement of
`NAL start code` with `NAL length`. In the absence of `NAL start code`
it was automatically a no-op.
PiperOrigin-RevId: 617193317
There is no super test which covers whole MP4 structure.
In all the E2E test, it verified against `ExtractorOutput` which
would remain same if there are changes in the box structure.
PiperOrigin-RevId: 608310006
The public APIs of these modules reference symbols in some of their
dependencies, so these should be API dependencies, not implementation:
> An API dependency is one that contains at least one type that is
> exposed in the library binary interface, often referred to as its ABI
> (Application Binary Interface).
https://docs.gradle.org/current/userguide/java_library_plugin.html#sec:java_library_recognizing_dependencies
Transformer also uses symbols from `lib-common`, but these are already
an API dep of `lib-exoplayer` so no need to duplicate that here.
PiperOrigin-RevId: 605660621
The new API will take both `creation time` and `modification time`.
Till now, Mp4Muxer wrote `modification time` in both
`creation time` and `modification time` field, which was
incorrect.
PiperOrigin-RevId: 605590623
The implementation of fragmented MP4 caused a regression where muxer
started writing empty tracks even for non fragmented MP4.
PiperOrigin-RevId: 603091348
As per MP4 spec ISO 14496-12: 8.7.5 Chunk Offset Box, Both "stco" and
"co64" can be used to store chunk offsets. While "stco" supports 32-bit
offsets, "co64" supports 64-bit offsets.
In non fragmented MP4, the mdat box can be extremely large, hence muxer
uses "co64" box.
But for fragmented MP4, muxer does not write any data in this chunk offset
box (present in "moov" box) because all sample related info is present in
"moof" box.
Technically, "co64" box should also work in fragmented MP4because
its empty only but QuickTime player fails to play video if "co64"
box is present in fragmented MP4 output file.
Testing: Verified that QuickTime player does not play video when "co64"
box is present but is able to play when "stco" box is present.
#minor-release
PiperOrigin-RevId: 601147046
This fix makes output playable on VLC player.
The output does not play on QuickTime player which is being fixed in
a separate CL.
#minor-release
PiperOrigin-RevId: 601118813
Earlier implementation processed each track (pending sample's buffer info)
individually when writing their corresponding "traf" box in a fragment.
The change involves processing all tracks before start writing "traf" boxes.
#minor-release
PiperOrigin-RevId: 600811093
