The Matroska demuxer has three functions for creating packets out of
the data read: One for certain RealAudio codecs (ATRAC3, cook, sipr,
RealAudio 28.8), one for WebVTT (actually, the WebM flavour of it) and
one for all the others. Only the last function supported Matroska's
ContentCompression (e.g. it reversed zlib compression or added the
removed headers to the packets). But in Matroska, all tracks are allowed
to be compressed. This commit adds support for this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Matroska is built around the principle that a reader does not need to
understand everything in a file in order to be able to make use of it;
it just needs to ignore the data it doesn't know about.
Our demuxer typically follows this principle, but there is one important
instance where it does not: A Block belonging to a TrackEntry with no
associated stream is treated as invalid data (i.e. the demuxer will try
to resync to the next level 1 element because it takes this as a sign
that it has lost sync). Given that we do not create streams if we don't
know or don't support the type of the TrackEntry, this impairs this
demuxer's forward compability.
Furthermore, ignoring Blocks belonging to a TrackEntry without
corresponding stream can (in future commits) also be used to ignore
TrackEntries with obviously bogus entries without affecting the other
TrackEntries (by not creating a stream for said TrackEntry).
Finally, given that matroska_find_track_by_num() already emits its own
error message in case there is no TrackEntry with a given TrackNumber,
the error message (with level AV_LOG_INFO) for this can be removed.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
A Block (meaning both a Block in a BlockGroup as well as a SimpleBlock)
must have at least three bytes after the field containing the encoded
TrackNumber. So if there are <= 3 bytes, the Matroska demuxer would
skip this block, believing it to be an empty, but valid Block.
This might discard valid nonempty Blocks, namely if the track uses header
stripping. And certain definitely spec-incompliant Blocks don't raise
errors: Those with two or less bytes left after the encoded TrackNumber
and those with three bytes left, but with flags indicating that the Block
uses lacing as then there has to be further data describing the lacing.
Furthermore, zero-sized packets were still possible because only the
size of the last entry of a lace was checked.
This commit fixes this. All spec-compliant Blocks that contain data
(even if side data only) are now returned to the caller; spec-compliant
Blocks that don't contain anything are not returned.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Some conditions which don't change and which can therefore be checked
in read_header() were instead rechecked upon parsing each block. This
has been changed.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The Matroska demuxer splits every sequence of h Matroska Blocks into
h * w / cfs packets of size cfs; here h (sub_packet_h), w (frame_size)
and cfs (coded_framesize) are parameters from the track's CodecPrivate.
It does this by splitting the Block's data in h/2 pieces of size cfs each
and putting them into a buffer at offset m * 2 * w + n * cfs where
m (range 0..(h/2 - 1)) indicates the index of the current piece in the
current Block and n (range 0..(h - 1)) is the index of the current Block
in the current sequence of Blocks. The data in this buffer is then used
for the output packets.
The problem is that there is currently no check to actually guarantee
that no uninitialized data will be output. One instance where this is
trivially so is if h == 1; another is if cfs * h is so small that the
input pieces do not cover everything that is output. In order to
preclude this, rmdec.c checks for h * cfs == 2 * w and h >= 2. The
former requirement certainly makes much sense, as it means that for
every given m the input pieces (corresponding to the h different values
of n) form a nonoverlapping partition of the two adjacent frames of size w
corresponding to m. But precluding h == 1 is not enough, other odd
values can cause problems, too. That is because the assumption behind
the code is that h frames of size w contain data to be output, although
the real number is h/2 * 2. E.g. for h = 3, cfs = 2 and w = 3 the
current code would output four (== h * w / cfs) packets. although only
data for three (== h/2 * h) packets has been read.
(Notice that if h * cfs == 2 * w, h being even is equivalent to
cfs dividing w; the latter condition also seems very reasonable:
It means that the subframes are a partition of the frames.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
RealAudio 28.8 (like other RealAudio codecs) uses a special demuxing
mode in which the data of the existing Matroska Blocks is not simply
forwarded as-is. Instead data from several Blocks is recombined
together to output several packets. The parameters governing this
process are parsed from the CodecPrivate: Coded framesize (cfs), frame
size (w) and sub_packet_h (h).
During demuxing, h/2 pieces of data of size cfs each are read from every
Matroska (Simple)Block and put at offset m * 2 * w + n * cfs of a buffer
of size h * w, where m ranges from 0 to h/2 - 1 for each Block while n
is initially zero and incremented after a Block has been parsed until it
is h, at which poin the assembled packets are output and n reset.
The highest offset is given by (h/2 - 1) * 2 * w + (h - 1) * cfs + cfs
while the destination buffer's size is given by h * w. For even h, this
leads to a buffer overflow (and potential segfault) if h * cfs > 2 * w;
for odd h, the condition is h * cfs > 3 * w.
This commit adds a check to rule this out.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
RealAudio 28.8 does not need or use sub_packet_size for its demuxing
and this field is therefore commonly set to zero. But since 18ca491b
the Real Audio specific demuxing is no longer applied if sub_packet_size
is zero because the codepath for cook and ATRAC3 divide by it; this made
these files undecodable.
Furthermore, since 569d18aa (merged in 2c8d876d) sub_packet_size being
zero is used as an indicator for invalid data, so that a file containing
such a track was completely skipped.
This commit fixes this by not checking sub_packet_size for RealAudio
28.8 at all.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
They need a special parsing mode and in order to find out whether this
mode is in use, several checks have to be performed. They can all be
combined into one: If the buffer that is only used to assemble their
packets has been allocated, use the RealAudio parsing mode.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Only flavors 0..3 seem to exist. E.g. rmdec.c treats any flavor > 3
as invalid data. Furthermore, we do not know how big the packets to
create ought to be given that for sipr these values are not read from
the bitstream, but from a table.
Furthermore, flavor is only used for sipr, so only check it for sipr;
rmdec.c does the same. (The old check for flavor being < 0 was
always wrong given that flavor is an int that is read via avio_rb16(),
so it has been removed completely.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This makes decoding far more robust, since OggS, the ogg magic,
can be commonly found randomly in streams, which previously made
the demuxer think there's a new stream or a change in such.
hdsenc already had an explicit function to free all allocations in case
of an error, but it was not marked as deinit function, so that it was
not called automatically when the AVFormatContext for muxing gets freed.
Using an explicit deinit function also makes the code cleaner by
allowing to return immediately without "goto fail".
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Current muxers only use a single bitstream filter, so there is no need to
maintain code which operates on a list of bitstream filters. When multiple
bitstream filters are needed muxers can simply use a list bitstream filter.
If there is a use case in the future when different bitstream filters should be
added at subsequent packets then a new API possibly involving reconfiguring the
list bitstream filter can be added knowing the exact requirements.
Signed-off-by: Marton Balint <cus@passwd.hu>
mux.c was split from utils.c in 55f9037f38
and during this split all headers were simply copied without checking if
they were only needed in the part that stayed in utils.c (or whether
these haeders were needed at all). As a result quite a lot of headers
in mux.c are unnecessary. This commit removes them.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
stdarg.h has been included in 780d7897a9
for ff_url_join(). This header became unnecessary when this function was
moved into a separate file in df9f22d42b.
libavutil/pixdesc.h has been included for av_get_pix_fmt_name() in
603b8bc2a1 and is unused since commit
2fb7501938 that removed the stuff belonging
to FF_API_FORMAT_PARAMETERS. Notice that this file still uses
AV_PIX_FMT_NONE and that therefore the header libavutil/pixfmt.h has
been included (this header is included in pixdesc.h as well as also in
libavutil/internal.h which is also included).
libavutil/time_internal.h has been included for gmtime_r() in commit
e7dd97b5d8cd6ea150446591f37a5946e8ab7cfb; it is unused since commit
b72a7b96f8 which basically moved the code
making use of gmtime_r() to libavutil/dict.c to use in
avpriv_dict_set_timestamp().
audiointerleave.h has been added in c26e58e32c
because of ff_interleave_compare_dts() (at that time the muxing code
was not split from utils.c yet); said function became static in commit
101e1f6ff9, making this header redundant.
metadata.h has been mostly included for what now resides in
libavutil/dict.h. The stuff that now resides in metadata.h has only been
used briefly: From commits ed7694d8cf to
d60a9f52eb.
riff.h has been added in 45da8124a0
because riff.h once contained declarations for (ff_)codec_get_tag().
This was changed in bfe5454cd2.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
support dvcC/dvcC box from spec Dolby Vision Streams Within the
ISO Base MediaFile Format Version 2.1.2
(https://www.dolby.com/in/en/technologies/dolby-vision/dolby-vision\
-bitstreams-within-the-iso-base-media-file-format-v2.1.2.pdf)
export the DOVI information to sidedata.
Signed-off-by: vacingfang <vacingfang@tencent.com>
support DOVI Video Stream Descriptor from Dolby Vision Streams
Within the MPEG-2 Transport Stream Format V1.2
From the spec: https://www.dolby.com/us/en/technologies/\
dolby-vision/dolby-vision-bitstreams-in-mpeg-2-transport-\
stream-multiplex-v1.2.pdf.
export the DOVI information with sidedata.
Signed-off-by: vacingfang <vacingfang@tencent.com>
Reindentation, removal of { } if they contain only one statement
and moving the return statement to a line of its own in situations
like "if (ret < 0) return ret;". Moreover, several overlong lines
were made shorter and a camelCase variable received a name in line
with our naming conventions.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Up until now, the Matroska muxer would mark a track as default if it had
the disposition AV_DISPOSITION_DEFAULT or if there was no track with
AV_DISPOSITION_DEFAULT set; in the latter case even more than one track
of a kind (audio, video, subtitles) was marked as default which is not
sensible.
This commit changes the logic used to mark tracks as default. There are
now three modes for this:
a) In the "infer" mode the first track of every type (audio, video,
subtitles) with default disposition set will be marked as default; if
there is no such track (for a given type), then the first track of this
type (if existing) will be marked as default. This behaviour is inspired
by mkvmerge. It ensures that the default flags will be set in a sensible
way even if the input comes from containers that lack the concept of
default flags. This mode is the default mode.
b) The "infer_no_subs" mode is similar to the "infer" mode; the
difference is that if no subtitle track with default disposition exists,
no subtitle track will be marked as default at all.
c) The "passthrough" mode: Here the track will be marked as default if
and only the corresponding input stream had disposition default.
This fixes ticket #8173 (the passthrough mode is ideal for this) as
well as ticket #8416 (the "infer_no_subs" mode leads to the desired
output).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
At the end of encoding, the FLAC encoder sends a packet whose side data
contains updated extradata (e.g. a correct md5 checksum). The Matroska
muxer uses this to update the CodecPrivate.
In doing so, the stream's codecpar was copied. But given that writing
a FLAC CodecPrivate does not modify the used AVCodecParameters at all,
there is no need to do so and this commit changes this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
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>
The Matroska muxer does not write every stream as a Matroska track;
some streams are written as AttachedFile. But should no stream be
written as a Matroska track, the Matroska muxer would nevertheless
write a Tracks element without a TrackEntry. This is against the spec.
This commit changes this and only writes a Tracks if there is a Matroska
track.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
As WebM doesn't support Attachments, the Matroska muxer drops them when
in WebM mode. This happened silently until this commit which adds a
warning for this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
In order to determine whether the current Cluster needs to be closed
because of the limits on clustersize and clustertime,
mkv_write_packet() would first get the size of the current Cluster by
applying avio_tell() on the dynamic buffer holding the current Cluster.
It did this without checking whether there is a dynamic buffer for
writing Clusters open right now.
In this case (which happens when writing the first packet)
avio_tell() returned AVERROR(EINVAL); yet it is not good to rely on
avio_tell() (or actually, avio_seek()) to handle the situation
gracefully.
Fixing this is easy: Only check whether a Cluster needs to be closed
if a Cluster is in fact open.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
When creating DASH streams, the TrackNumber is externally prescribed
and not derived from the number of streams in the AVFormatContext, so
if the number of tracks for a file using an explicit TrackNumber was
more than one, the resulting file would be broken (it would be impossible
to tell to which track a Block belongs if different tracks share the
same TrackNumber). So disallow this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
