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>
This muxer currently uses two ways to ensure that no bytes
are wasted by writing unnecessary long EBML length fields
for Master elements and the (Simple)Block element
(all the other elements are fine as one either already has
the right length or getting the actual length is easy
and necessary anyway):
Either use an upper bound that is good enough in case one
is available or write the data into a dynamic buffer first
to get the length; the former approach is impossible in
lots of cases, whereas the latter incurs allocations and
memcpying. It is therefore unfeasible to use the latter
for e.g. the attachments or the BlockGroups.
This patch adds a third alternative to complement the other two:
It consists of an EbmlWriter that one can add EBML elements to
that can be written later by calling ebml_writer_write();
the latter function first traverses the written elements recursively
and calculates the length of each element; then a second pass
is performed in which all the elements are written directly
(without any seeks).
This new API also performs checks for overlong elements;
this is in contrast to put_ebml_string() which simply performs
a size_t->int conversion even for strings originating from the user.
The new API is designed to have very low overhead: It uses
stack arrays and performs no allocations; this also comes
at a price: Right now, it can only be used in contexts in which
there is a compile-time upper bound for the number of elements.
It is also incompatible with storing the offset of an element
in order to update this field later. Furthermore, it puts
the onus of memory management (i.e. ensuring that pointers stay valid)
on the user.
These restrictions might be overcome in the future.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This would happen in case non-WebVTT-subtitles had BlockAdditional
or DiscardPadding side-data. Given that these are not accounted for
in the length of the outer BlockGroup (which is a quite sharp upper
bound) it is possible for the outer BlockGroup to use an insufficient
number of bytes which leads to an assert in end_ebml_master().
Fix this by not opening a second BlockGroup inside an already opened
BlockGroup.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This is similar to the faststart option of the mov muxer, yet
in contrast to it it works together with reserve_index_space
(the equivalent to reserved_moov_size): If the reserved space
does not suffice, the data is shifted; if not, the Cues are
written at the front without shifting the data.
Several tests that cover (not only) this have been added.
Implements #7017.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The Matroska muxer has quite a lot of dependencies and lots of them
are unnecessary for WebM. By disabling the Matroska-only code
at compile time one can get rid of them.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
In this case ff_isom_put_dvcc_dvvc() might not be available, leading
to linking failures. Given that WebM currently doesn't support DOVI,
this is fixed by #if'ing the offending code away if the Matroska
muxer is not enabled.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Adds handling of dvcC/dvvC block addition mappings.
The parsing creates AVDOVIDecoderConfigurationRecord side data.
The configuration block is written when muxing into Matroska,
if DOVI side data is present for the track.
Most of the Matroska element parsing is based on Plex's FFmpeg source code.
Signed-off-by: quietvoid <tcChlisop0@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Currently they are ordered as-written (i.e. by increasing position);
in case av_interleaved_write_frame() is used, this is (mostly)
the same as ordered by increasing dts.
Yet the Matroska specification strongly recommends (SHOULD) that
the CuePoints be sorted by CueTime. mkvalidator warns when they are
not. Therefore this commit sorts them accordingly.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
For most check_bitstream() functions this just avoids having
to dereference s->streams[pkt->stream_index] themselves; but for
meta-muxers it will allow to forward the packet to stream with
a different stream_index (belonging to a different AVFormatContext)
without using a spare packet.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Do this by allocating AVFormatContext together with the data that is
currently in AVFormatInternal; or rather: Put AVFormatContext at the
beginning of a new structure called FFFormatContext (which encompasses
more than just the internal fields and is a proper context in its own
right, hence the name) and remove AVFormatInternal altogether.
The biggest simplifications occured in avformat_alloc_context(), where
one can now simply call avformat_free_context() in case of errors.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Currently AVIOContext's private fields are all over AVIOContext.
This commit moves them into a new structure in avio_internal.h instead.
Said structure contains the public AVIOContext as its first element
in order to avoid having to allocate a separate AVIOContextInternal
which is costly for those use cases where one just wants to access
an already existing buffer via the AVIOContext-API.
For these cases ffio_init_context() can't fail and always returned zero,
which was typically not checked. Therefore it has been made to not
return anything.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
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>
The Matroska specifications have evolved and now allow to mark
multiple tracks of the same kind as default (whether this was legal or
not before was dubious; e.g. mkvmerge disallowed it). Yet when the
Matroska muxer is set to infer default dispositions if absent, it also
enforced the now outdated restriction. So update this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The child_class_next API relied on different (de)muxers to use
different AVClasses; yet this API has been replaced by
child_class_iterate.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This is possible now that the next-API is gone.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: James Almer <jamrial@gmail.com>
ffio_fill() is used when initially writing unknown length elements;
yet it can happen that the amount of bytes written by it is zero in
which case it is of course unnecessary to ever call it. Whether it is
possible to know this during compiletime depends upon how aggressively
the compiler inlines function calls (i.e. if it inlines calls to
start_ebml_master() where the upper bound for the size of the element
implies that the size will be written on one byte) and this depends upon
optimization settings. It is not the aim of this patch to inline all
calls where it is known that ffio_fill() will be unnecessary, but merely
to make compilers that inline such calls aware of the fact that writing
zero bytes with ffio_fill() is unnecessary. To this end
av_builtin_constant_p() is used to check whether the size is a
compiletime constant.
For GCC 10 this made a difference at -O3 only: The size of .text
decreased from 0x747F (with 29 calls to ffio_fill(), eight of which
use size zero) to 0x7337 (with 21 calls to ffio_fill(), zero of which
use size zero).
For Clang 11 it made a difference at -O2 and -O3: At -O2, the size of
.text decreased from 0x879C to 0x871C (with eight calls to ffio_fill()
eliminated); at -O3 the size of .text decreased from 0xAF2F to 0xAEBF.
Once again, eight calls to ffio_fill() with size zero have been
eliminated.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The value zero for AVPacket.duration means that the duration is unknown,
which in practice means "play this subtitle until overridden by the next
subtitle". Yet for Matroska a BlockGroup with duration zero means
that the subtitle really has a duration zero. "Display until overridden"
is achieved by not setting a duration on the container level at all and
this is achieved by using a SimpleBlock or a BlockGroup without
duration. This commit implements this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
64 bits are needed in order to retain the uid values of Matroska
chapters; the type is kept signed because the semantics of NUT chapters
depend upon whether the id is > 0 or < 0.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Up until now, there has been no check that each chapter has a unique id;
there was only a check for whether a chapter id is zero (this happens
often when the chapters originated from a format that lacks the concept
of chapter id and simply counts from zero) which is invalid in Matroska.
In this case the chapter ids are offset by 1 to make them nonnegative.
Yet offsetting won't fix duplicate ids, therefore this is changed to
simply create new chapter uids when the input chapter uids don't conform
to the requirements of Matroska (in which case it can be presumed that
they did not originate from Matroska, so that we don't need to bother
to preserve them).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This is the Matroska equivalent of D_WEBVTT_DESCRIPTIONS and is
therefore only enabled for subtitles.
Reviewed-by: Ridley Combs <rcombs@rcombs.me>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
According to the new EBML specifications, a string element of length
zero would be read as the default value by a compliant parser.
Reviewed-by: Ridley Combs <rcombs@rcombs.me>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Some legacy applications such as AVI2MVE expect raw RGB bitmaps
to be stored bottom-up, whereas our RIFF BITMAPINFOHEADER assumes
they are always stored top-down and thus write a negative value
for height. This can prevent reading of these files.
Option flipped_raw_rgb added to AVI and Matroska muxers
which will write positive value for height when enabled.
Note that the user has to flip the bitmaps beforehand using other
means such as the vflip filter.
The argument pertaining to a printf %s conversion specifier must not
be NULL, even if the precision (i.e. the number of characters to write)
is zero. If it is NULL, it is undefined behaviour.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
av_stream_get_side_data() tells the caller whether a stream has side
data of a specific type; if present it can also tell the caller the size
of the side data via an optional argument. The Matroska muxer always
used this optional argument, although it doesn't really need the size,
as the relevant side-data are not buffers, but structures. So change
this.
Furthermore, relying on the size also made the code susceptible to
a quirk of av_stream_get_side_data(): It only sets the size argument if
it found side data of the desired type. mkv_write_video_color() checks
for side-data twice with the same variable for the size without resetting
the size in between; if the second type of side-data isn't present, the
size will still be what it was after the first call. This was not
dangerous in practice, as the check for the existence of the second
side-data compared the size with the expected size, so it would only be
problematic if lots of elements were to be added to AVContentLightMetadata.
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
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>
This is needed so that it can access mkv_write_tag() and mkv_check_tag()
without using forward declarations (which are unnecessary here).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Up until now, the Matroska muxer writes only one Tags level 1 element
and therefore using a certain place to store the dynamic buffer used for
writing it was hardcoded; yet the Matroska specifications allow an
unlimited amount of Tags elements and we have reason to write a second
one: If chapters are provided after writing the header, they are written
when writing the trailer; yet the corresponding tags are ignored. This
can be fixed by writing them in a second Tags element.
Also use a MatroskaMuxContext * instead of an AVFormatContext * as
parameter in mkv_write_tag() and mkv_write_tag_targets() as that is all
these functions use.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Mostly reindentation after the last commit. Also remove a variable that
is always zero; move another variable to a more local scope and don't
assign a value to a local variable immediately before leaving the function.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Andreas Rheinhardt
quietvoid
Andreas Rheinhardt
Anton Khirnov
James Almer
Gyan Doshi