Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.
In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.
There are multiple important problems with this approach:
- the fields in AVCodecContext are in general one of
* stream parameters
* codec options
* codec state
However, it's not clear which ones are which. It is consequently
unclear which fields are a demuxer allowed to set or a muxer allowed to
read. This leads to erratic behaviour depending on whether decoding or
encoding is being performed or not (and whether it uses the AVStream
embedded codec context).
- various synchronization issues arising from the fact that the same
context is used by several different APIs (muxers/demuxers,
parsers, bitstream filters and encoders/decoders) simultaneously, with
there being no clear rules for who can modify what and the different
processes being typically delayed with respect to each other.
- avformat_find_stream_info() making it necessary to support opening
and closing a single codec context multiple times, thus
complicating the semantics of freeing various allocated objects in the
codec context.
Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
Current if statement would always be false due to assigning the value of
S_OK which equals 0.
Signed-off-by: FearThe1337 <git@fearthe1337.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The next frame time could slip, causing the frame rate to drop until
frames were dropped. Now will capture at the next correct moment instead.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
As it is already written in the documentation, BMD DeckLink cards
are capable of capturing 2, 8 or 16 audio channels (for SDI Inputs).
Currently the value is hardcoded to 2. Introduces new option.
Reviewed-by: Deti Fliegl <deti@fliegl.de>
Signed-off-by: Matthias Hunstock <atze@fem.tu-ilmenau.de>
Signed-off-by: Marton Balint <cus@passwd.hu>
Libav, for some reason, merged this as a public API function. This will
aid in future merges.
A define is left for backwards compat, just in case some person
used it, since it is in a public header.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Here it is mostly a cosmetic change, but there might be benefits in that
there are no compat hacks for lround, while there are for lrint.
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This fixes extra semicolons that clang 3.7 on GNU/Linux warns about.
These were trigggered when built under -Wpedantic, which essentially
checks for strict ISO compliance in numerous ways.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This does not trigger any warnings, but adds robustness.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This does not trigger any warnings but adds robustness.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This does not trigger any warnings, but adds robustness.
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
FAIL(ret) expands to statements including a silly ret=ret.
This triggers a -Wself-assign on confirmed clang 3.6, and so we fix it.
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Michael Niedermayer
Lou Logan
Anton Khirnov
Josh de Kock
Metaksakis Georgios
FearThe1337
Trevor \\\\ Higgins
Timothy Gu
Matthias Hunstock
Paul B Mahol
Michael Ira Krufky
Marton Balint
Derek Buitenhuis
Eddie Hao
Ganesh Ajjanagadde
Alexandre Lision
Matt Oliver
Hendrik Leppkes
Luca Barbato
Vittorio Giovara
Clément Bœsch
Andreas Cadhalpun