Keep coded_frame.key_frame a write-only variable.

This change (and the following ones of the same kind) is mainly to
simplify wrapping this section with an #if FF_API block later on.

No functional changes are applied, the fields of the context coded_frame
fields are directly initialized, instead of keeping a reference to the
coded_frame itself.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

Its fields are never initialized to begin with.

coded_frame is already initialized where needed.

Add DCI 2k and 4k and uhd1 and uhd2.

Wait for async_depth frames before syncing.

Wait for async_depth frames before syncing.

This filter currently assumes that the input audio is continuous and
does some timestamps manipulation based on this assumption.

This is unnecessary if we are only converting the channel layout or the
sample format, without resampling. In such a case, just leave the
timestamps as they are.

The current code is less than straightforward due to the fact that
output streams can be created based on filtergraph definitions. This
change should make the code simpler and more readable. It will also be
useful in the future commits.

Since global options are processed before all the other options now, we
do not have to try creating the complex filtergraphs several times
anymore, it is enough to do it once after the input files are opened.

It is a better place for it, there is no reason to wait until
transcode_init().

Also, drop the now unused cmdutils_read_file(). There is no reason to
have two functions doing essentially the same thing.

It more logically belongs there.

This will be useful in the following commits.

There is only one decoder left that supports this (libopus, which is not
used by default since we have a native one) and this code goes against
the avconv design, since it propagates information back from the encoder
to decoder.

number of subpayloads should be always positive
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Signed-off-by: Anton Khirnov <anton@khirnov.net>

Signed-off-by: Anton Khirnov <anton@khirnov.net>

Signed-off-by: Anton Khirnov <anton@khirnov.net>

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

The upper halves are not guaranteed to be zero in x86-64.

Also use `test` instead of `and` when the result isn't used for anything other
than as a branch condition, this allows some register moves to be eliminated.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>