If a packet is not ready on the input selected by ffmpeg,
it will read from another input instead. If that happens
repeatedly, frames will accumulate somewhere later in the
processing to ensure streams synchronization. It can happen
in particular when reading from a slow medium or an
expensive lavfi filter graph.

Make reading from normal demuxers on non-streamed data and
from the lavfi pseudo-device blocking to avoid that.

Should fix trac ticket #3079.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Idea-by: ramiro
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

ffmpeg: Do not fill gap before the first decodable frame on single stream input files unless the user explicitly requests it.

Fixes different behavior to JM and probably several if not all
reference decoders.

We cannot just do this unconditionally as it would ruin AV sync in
some use cases.

Bug-Found-by: BugMaster
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Avoid the need for multiple potentially inconsistent access operations,
slightly factorize code.

ffmpeg: add max_error_rate to allow tuning the point decoding errors are considered a failure of the whole transcoding.

Suggested-by: Daemon404
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Allows, amongst other things, to override the size guessed
by the sub2video hack.

Note: the -s option could have more or less the same semantic,
but it receives a special treatment by the options system.

And re-enable the FATE test.

Signed-off-by: Jean First <jeanfirst@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This is very close to what the default does currently

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This avoids per parameter changes in ffmpeg at the cost of making access
somewhat more annoying.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Until now, the end_display_time was ignored, making single
packets subtitles (like dvdsub) stay indefinitely.

start_display_time was also ignored, but is it almost always 0.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Normally we discard things prior to the intended start
for stream copy this is not always possible, and its not done by default
this option allows discarding to be enabled

this is primarely usefull when transcoding a video and stream copying an
audio stream.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

With this option, transcoding DVB subtitles becomes possible.