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Commit Graph

31 Commits

Author SHA1 Message Date
Andreas Rheinhardt
e8065c7def avformat/matroskaenc: Don't waste bytes on Video element length fields
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-01-19 11:50:27 +01:00
Andreas Rheinhardt
0148e85c3c avformat/matroskaenc: Don't waste bytes on SimpleTags length fields
Also check the (user-provided) tags for being overlong; the earlier
code had an implicit unchecked size_t->int conversion.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-01-19 11:34:36 +01:00
Andreas Rheinhardt
750631b098 avformat/matroskaenc: Pass dispositions through unchanged by default
Up until now, the Matroska muxer did not use the dispositions it is
given as-is; instead it by default overrode the disposition of the first
track of a kind (audio, video, subtitles) if no track of this kind has
the default disposition set. And up until recently, it also enforced
by default that no more than one track of each kind be marked as
default.

The rationale for the former is that there are lots of containers which
lack the concept of default streams, so that it is not uncommon for no
stream to be marked as default at all; the rationale for the latter was
that up until recently, it was dubious whether the Matroska specification
allowed more than one default stream for track type (e.g. mkvmerge
disallowed it). It was this point which led to the implementation of
the above mentioned behaviour inspired by mkvmerge.

Yet the Matroska specifications have changed and now explicitly allow
to set more than one track of each type as default, so that the main
reason of not using the dispositions as-is was rendered moot. Therefore
this commit changes the default to pass the disposition through.

The matroska-mpegts-remux FATE-test has been updated to still use the
old "infer" mode so that it is still covered by FATE; the
matroska-zero-length-block test has also been updated to cover
the infer_no_subs mode. The references for lots of other FATE tests
needed to be updated because of a newly added FlagDefault element with
value zero (whereas a FlagDefault with value 1 needn't be coded at all,
as it coincided with the default value of said element).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2021-08-24 04:23:29 +02:00
Andreas Rheinhardt
4ebfc13c33 avformat/matroskaenc: Don't ignore tags of chapters written late
The Matroska muxer writes the Chapters early when chapters were already
available when writing the header; in this case any tags pertaining to
these chapters get written, too.

Yet if no chapters had been supplied before writing the header, Chapters
can also be written when writing the trailer if any are supplied. Tags
belonging to these chapters were up until now completely ignored.

This commit changes this: Writing the tags belonging to chapters has
been moved to mkv_write_chapters(). If mkv_write_tags() has not been
called yet (i.e. when chapters are written when writing the header),
the AVIOContext for writing the ordinary Tags element is used, but not
output, as this is left to mkv_write_tags() in order to only write one
Tags element. Yet if mkv_write_tags() has already been called,
mkv_write_chapters() will output a Tags element of its own which only
contains the tags for chapters.

When chapters are available initially, the corresponding tags will now
be the first tags in the Tags element; but the ordering of tags in Tags
is irrelevant anyway.

This commit also makes chapter_id_offset local to mkv_write_chapters()
as it is used only there and not reused at all.

Potentially writing a second Tags element means that the maximum number
of SeekHead entries had to be incremented. All the changes to FATE
result from the ensuing increase in the amount of space reserved for the
SeekHead (21 bytes more).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-05-19 03:34:44 +02:00
Andreas Rheinhardt
5b6e164b4b avformat/matroskaenc: Don't waste bytes on length fields
Several EBML Master elements for which a good upper bound of the final
length was available were nevertheless written without giving an
upper bound of the final length to start_ebml_master(), so that their
length fields were eight bytes long. This has been changed.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-04-21 08:11:09 +02:00
Andreas Rheinhardt
ccadd00a4a avformat/matroskaenc: Make output more deterministic
Using random values for TrackUID and FileUID (as happens when the
AVFMT_FLAG_BITEXACT flag is not set) has the obvious downside of making
the output indeterministic. This commit mitigates this by writing the
potentially random values with a fixed size of eight byte, even if their
actual values would fit into less than eight bytes. This ensures that
even in non-bitexact mode, the differences between two files generated
with the same settings are restricted to a few bytes in the header.
(Namely the SegmentUID, the TrackUIDs (in Tracks as well as when
referencing them via TagTrackUID), the FileUIDs (in Attachments as
well as in TagAttachmentUID) as well as the CRC-32 checksums of the
Info, Tracks, Attachments and Tags level-1-elements.) Without this
patch, there might be an offset/a size difference between two such
files.

The FATE-tests had to be updated because the fixed-sized UIDs are also
used in bitexact mode.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-04-13 08:43:14 +02:00
Andreas Rheinhardt
bd7dea3f4f avformat/matroskaenc: Don't waste bytes writing durations
Tags in the Matroska file format can be summarized as follows: There is
a level 1-element called Tags containing one or many Tag elements each
of which in turn contain a Targets element and one or many SimpleTags.
Each SimpleTag roughly corresponds to a single key-value pair similar to
an AVDictionaryEntry. The Targets meanwhile contains information to what
the metadata contained in the SimpleTags contained in the containing Tag
applies (i.e. to the file as a whole or to an individual track).

The Matroska muxer writes such metadata. It puts the metadata of every
stream into a Tag whose Targets makes it point to the corresponding
track. And if the output is seekable, then it also adds another Tag for
each track whose Targets corresponds to the track and where it reserves
space in a SimpleTag to write the duration at the end of the muxing
process into.

Yet there is no reason to write two Tag elements for a track and a few
bytes (typically 24 bytes per track) can be saved by adding the duration
SimpleTag to the other Tag of the same track (if it exists).

FATE has been updated because the output files changed. (Tests that
write to unseekable output (pipes) needn't be updated (no duration tag
has ever been written for them) and the same applies to tests without
further metadata.)

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-04-13 08:08:42 +02:00
Andreas Rheinhardt
dc2f6b54ac avformat/matroskaenc: Avoid allocations for SeekHead
Up until e7ddafd5, the Matroska muxer wrote two SeekHeads: One at the
beginning referencing the main level 1 elements (i.e. not the Clusters)
and one at the end, referencing the Clusters. This second SeekHead was
useless and has therefore been removed. Yet the SeekHead-related
functions and structures are still geared towards this usecase: They
are built around an allocated array of variable size that gets
reallocated every time an element is added to it although the maximum
number of Seek entries is a small compile-time constant, so that one should
rather include the array in the SeekHead structure itself; and said
structure should be contained in the MatroskaMuxContext instead of being
allocated separately.

The earlier code reserved space for a SeekHead with 10 entries, although
we currently write at most 6. Reducing said number implied that every
Matroska/Webm file will be 84 bytes smaller and required to adapt
several FATE tests; furthermore, the reserved amount overestimated the
amount needed for for the SeekHead's length field and how many bytes
need to be reserved to write a EBML Void element, bringing the total
reduction to 89 bytes.

This also fixes a potential segfault: If !mkv->is_live and if the
AVIOContext is initially unseekable when writing the header, the
SeekHead is already written when writing the header and this used to
free the SeekHead-related structures that have been allocated. But if
the AVIOContext happens to be seekable when writing the trailer, it will
be attempted to write the SeekHead again which will lead to segfaults
because the corresponding structures have already been freed.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-03-26 03:19:56 +01:00
Andreas Rheinhardt
0b61ddb576 avformat/matroskaenc: Don't waste bytes writing level 1 elements
Up until now, the length field of most level 1 elements has been written
using eight bytes, although it is known in advance how much space the
content of said elements will take up so that it would be possible to
determine the minimal amount of bytes for the length field. This
commit changes this.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2019-05-08 13:02:30 -03:00
Andreas Rheinhardt
4e6df068b5 avformat/matroskaenc: Don't waste bytes in EBML Header
Up until now the EBML Header length field has been written with eight
bytes, although the EBML Header is always so small that only one byte
is needed for it. This patch saves seven bytes for every Matroska/Webm
file.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2019-05-08 13:02:29 -03:00
James Almer
90826031a2 avformat/matroskaenc: write a DisplayUnit element when aspect ratio is unknown
We don't currently support values 1 (centimeters), 2 (inches) or 3 (DAR),
only the default value 0 (pixels) which doesn't need to be written.

The fate refs are updated as unknown SAR is now signaled in the output
files with the addition of the new element.

Reviewed-by: Carl Eugen Hoyos <ceffmpeg@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2016-10-15 20:48:03 -03:00
James Almer
3bcadf8227 avformat/matroskaenc: write a CRC32 element on Info
Finishes implementing ticket #4347

Tested-by: Dave Rice <dave@dericed.com>
Tested-by: Jerome Martinez <jerome@mediaarea.net>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
2016-10-06 17:16:12 -03:00
James Almer
650e17d88b avformat/matroskaenc: write a CRC32 element on Tags
Implements part of ticket #4347

Tested-by: Dave Rice <dave@dericed.com>
Tested-by: Jerome Martinez <jerome@mediaarea.net>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
2016-10-06 17:13:59 -03:00
James Almer
87ce2595de avformat/matroskaenc: write a CRC32 element on Tracks
Implements part of ticket #4347

Tested-by: Dave Rice <dave@dericed.com>
Tested-by: Jerome Martinez <jerome@mediaarea.net>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
2016-10-06 17:05:03 -03:00
James Almer
3b189fae73 avformat/matroskaenc: write a CRC32 element on SeekHead
Implements part of ticket #4347

Tested-by: Dave Rice <dave@dericed.com>
Tested-by: Jerome Martinez <jerome@mediaarea.net>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
2016-10-06 16:59:09 -03:00
James Almer
6724525a15 avformat/matroskaenc: write a CRC32 element on each Cluster
Implements part of ticket #4347

Tested-by: Dave Rice <dave@dericed.com>
Tested-by: Jerome Martinez <jerome@mediaarea.net>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
2016-10-06 16:54:07 -03:00
Derek Buitenhuis
ee865e9780 Merge commit 'e3453fd44480d903338c663238bf280215dd9a07'
* commit 'e3453fd44480d903338c663238bf280215dd9a07':
  matroska: Write the field order information

Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
2016-05-08 23:25:58 +01:00
Luca Barbato
e3453fd444 matroska: Write the field order information
And bump the document version to 4.
2016-04-03 19:36:57 +02:00
Sasi Inguva
31852540d4 libavformat/matroska: Write stream durations in metadata, in the format of mkvmerge.
Compute individual stream durations in matroska muxer.
Write them as string tags in the same format as mkvmerge tool does.

Signed-off-by: Sasi Inguva <isasi@google.com>
2015-08-05 22:29:23 +02:00
Anton Khirnov
962d631573 matroskaenc: set the stream timebase earlier
Fixes calculating the ts offset for audio codecs with delay.
2014-05-29 08:01:58 +02:00
Anton Khirnov
81eec081af matroskaenc: base DefaultDuration on the framerate, not the codec timebase
This results in DefaultDuration not being written when the framerate is
not known, but as this field is purely informative, this should not
break any sane demuxers.
2014-05-29 08:00:57 +02:00
Michael Niedermayer
0c152fe916 ffmpeg: prefix encoder with "Lavc " in bitexact mode
This avoids misleading encoder names like "encoder = prores"

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2014-05-18 22:57:20 +02:00
Michael Niedermayer
1e49439f04 Merge commit '6656370b858329ca07a60a2de954d5e90daa0206'
* commit '6656370b858329ca07a60a2de954d5e90daa0206':
  avconv: set the "encoder" tag when transcoding

Conflicts:
	ffmpeg.c
	tests/ref/lavf/mkv
	tests/ref/seek/lavf-mkv

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2014-05-18 21:31:51 +02:00
Anton Khirnov
6656370b85 avconv: set the "encoder" tag when transcoding 2014-05-18 20:33:46 +02:00
Anton Khirnov
a1aa37dd0b matroskaenc: write CodecDelay 2014-05-01 08:03:51 +02:00
James Almer
ea70e2f2d7 matroskaenc: Write muxingapp and writingapp elements when using bitexact flag
Files won't validate with mkvalidtor if these two elements are missing.
Use a const "Lavf" string that wont change with library version bumps.

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2013-09-18 23:06:59 +02:00
John Stebbins
f812eeda17 matroskaenc: Fix writing TRACKDEFAULTFLAG
The element was only being written when the value == 1.  But the default
value of this element is 1, so this has no useful effect.  This element
needs to be written when the value == 0.

Signed-off-by: Anton Khirnov <anton@khirnov.net>
2013-08-27 14:00:31 +02:00
James Almer
088ed53146 lavf/matroskaenc: Check for valid metadata before creating tags
Tags must have at least one SimpleTag element to be spec conformant.
Updated lavf-mkv and seek-lavf-mkv FATE references as the tests were affected by
this.

Fixes ticket #2785

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2013-07-17 12:18:27 +02:00
Luca Barbato
c2cb01d418 lavf: introduce AVFMT_TS_NEGATIVE
Most formats do not support negative timestamps, shift them to avoid
unexpected behaviour and a number of bad crashes.

CC:libav-stable@libav.org

Signed-off-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
2013-04-25 10:13:27 +02:00
Michael Niedermayer
7711f19eda Merge commit 'e816034a5fa131b13c4ad87bb0b5065b4f5697c6'
* commit 'e816034a5fa131b13c4ad87bb0b5065b4f5697c6':
  fate-seek: remove use of gnu make 3.82 only private modifier
  fate: move vsynth reference files to their own directory
  fate: move fate-acodec reference files to their own dir
  configure: avplay now depends on avresample
  fate: split dependencies for fate-seek tests

Conflicts:
	configure
	tests/fate/seek.mak

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-12-03 02:33:27 +01:00
Janne Grunau
abab0435d4 fate: split dependencies for fate-seek tests
Each fate-seek test depends now only on the corresponding fate-acodec,
fate-vsynth2 or fate-lavf test which creates the file seek-tests
operates on. The tests and references are renamed to match the test they
depend on.
2012-12-02 23:25:41 +01:00