mem: Handle av_reallocp(..., 0) properly

Previously this did a double free (and returned an error).

Reported-by: Justin Ruggles
Signed-off-by: Martin Storsjö <martin@martin.st>
Improve pullup documentation.

Mention that the fps filter should be used after pullup.
lavf: add SFTP protocol via libssh

Signed-off-by: Lukasz Marek <lukasz.m.luki@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '67e285ceca1cb602a5ab87010b30d904527924fe'

* commit '67e285ceca1cb602a5ab87010b30d904527924fe':
  mem: Handle av_reallocp(..., 0) properly

Merged-by: Michael Niedermayer <michaelni@gmx.at>
mpeg4dec: Ensure data is not clobbered too early.

Avoid overwriting the bitstream buffer data before we
have ended processing the frame.
This is necessary to fix hwaccels which might try to use
the buffer during the end_frame call.
I am not sure but it is possible this could even trigger
a use-after-free if the av_fast_malloc allocated a new buffer.
This would require that decode_slice did not wind the bitstream
forward all the way to the end, which does not currently happen in
normal streams.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Allow encoding YUVJ422P and YUVJ444P with libx264.