It is no longer needed given that the function pointers of the child
muxer's AVOutputFormat are no longer called directly.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The webm_chunk muxer caches its output to a dynamic buffer and when it
outputs anything, it explicitly flushes it. So set the flags indicating
that flushing after each packet should not be done automatically
(basically avoiding avio_write_marker() to be called by flush_if_needed()
in libavformat/mux.c).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
instead of calling the write_header/packet/trailer functions directly
via the function pointers. Also, use distinct AVStreams for the child
AVFormatContext (up until now the two AVFormatContexts shared their
AVStreams because allocating their own was deemed too onerous).
Using the function pointers directly meant that the Matroska muxer's
init-function was never called, because init-functions were only
introduced a few months after webm_chunk has been added and no one
thought of/bothered to adapt webm_chunk for this (when the init-function
was added in b287d7ea, the code setting the timebase was moved to it,
so that the timebases were no longer set to ms-precision when using
the webm_chunk muxer; this has been fixed after some time in 42a635dd
by setting the timebases direcly (instead of calling the init-function)).
And when 982a98a0 added a deinit-function for the Matroska muxer, it
introduced memleaks in webm_chunk, because the child muxer's internal
structures were no longer freed when calling write_trailer directly.
(Given that the init function has never ever been called, the child
muxer has never ever been properly initialized, so that the
deinit-function was not called when freeing the child context.)
This commit stops calling the function pointers directly and instead
uses the standard API functions for muxers. This fixes the above
mentioned memleaks. (Memleaks are still possible on error. This will be
fixed in a future commit that adds a deinit-function to webm_chunk
itself.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
In particular the flags are important so that AVFMT_FLAG_BITEXACT can be
honoured by the child muxer.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Up until now, it was simply presumed that the first packet had a pts of
zero; otherwise the duration of the first chunk was wrong.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The earlier version of the webm_chunk muxer had several bugs:
1. If the first packet of an audio stream didn't have a PTS of zero,
then no chunk will be started before a packet is delivered to the
underlying Matroska/WebM muxer, i.e. the AVFormatContext used to write
these packets had a NULL as AVIOContext for output. This is behind the
crash in ticket #5752.
2. If an error happens during writing a packet, the underlyimg
Matroska/WebM muxer context is freed. This leads to a use-after-free
coupled with a double-free in webm_chunk_write_trailer (which supposes
that the underlying AVFormatContext is still valid).
3. Even when no error occurs at all, webm_chunk_write_trailer is still
buggy: After the underlying Matroska/WebM muxer has written its trailer,
ending the chunk implicitly flushes it again which is illegal at this
point.
These bugs have been fixed.
Fixes#5752.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The last argument of av_strlcpy is supposed to contain the size of the
destination buffer, but it was filled with the size of the source
string, effectively negating its very purpose.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
My conversation from AVFormatContext->filename to AVFormatContext->url was
wrong in this case because get_chunk_filename uses filename as an output
buffer, and not as an input buffer.
Fixes ticket #7188.
Signed-off-by: Marton Balint <cus@passwd.hu>
Add an option to specify HTTP header in the WebM Chunk Muxer (this
works the same way as the 'method' parameter in the HLS muxer).
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Milliseconds is the de-factor precision for timestamps in
Matroska/WebM media.
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The flag was set unintentionally and the code will break if a NULL
packet is passed in.
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fix a duplicate memory allocation. priv_data should be allocated
in line 64 call to avformat_alloc_output_context2 since we pass
the correct AVFormat to it. This removes the duplicate allocation.
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Use dyn_duf to write chunks so that we create the actual chunk
file only after the entire chunk data is available. This will help
not confuse other software looking at the chunk file (e.g. a web
server) by seeing a zero length file when ffmpeg is writing into
it.
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fix a bug where the chunk muxer doesn't write the very first audio
packet (with pts == 0).
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This patch adds support for WebM Live Muxing by adding a new WebM
Chunk muxer. It writes out live WebM Chunks which can be used for
playback using Live DASH Clients.
Please see muxers.texi for sample usage.
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Andreas Rheinhardt
Michael Niedermayer
Carl Eugen Hoyos
Marton Balint
Vignesh Venkatasubramanian
Carl Eugen Hoyos
Vignesh Venkatasubramanian