Separate passing a new frame to VOs using the new API into two steps.
The first, vo_draw_image(), happens after a new frame is available
from the filter chain. In constrast to old behavior, now the frame is
not actually rendered yet at this point (though possible slice draw
calls can already reach the VO before). The second step,
vo_new_frame_imminent(), happens when we're close enough to the
display time of the new frame that we'll commit to flipping it as the
next action and will not change the OSD over the previous frame any
more.
This new behavior fixes a previous problem with vo_vdpau and vo_gl in
the situation where the player is paused after decoding a new frame
but before flipping it; previously changing OSD in that state would
switch to the new frame as a side effect. It would also allow an easy
way to fix extra output files produced with something like "--vo=png
--frames=1" with precise seeking, but this is not done yet.
The code now relies on a new mp_image from the filter chain staying
valid even after the vf_vo put_image() call providing it returns. In
other words decoders/filters must not deallocate or otherwise
invalidate their output frame between passing it forward and returning
from the decode/filter call.
Compiling with full features requires development files for several
external libraries. Below is a list of some important requirements. For
more information see the output of './configure --help' for a list of options,
or look at the list of enabled and disabled features printed after running
'./configure'. If you think you have support for some feature installed
but configure fails to detect it, the file config.log may contain information
about the reasons for the failure.
Libraries specific to particular video output methods
(you'll want at least one of VDPAU, GL or Xv):
- libvdpau (for VDPAU output, best choice for NVIDIA cards)
- libGL (OpenGL output)
- libXv (XVideo output)
general:
- libasound (ALSA audio output)
- various general X development libraries
- libfreetype
- libfontconfig
- libass
- FFmpeg libraries (libavutil libavcodec libavformat libswscale libpostproc)
Most of the above libraries are available in suitable versions on normal
Linux distributions. However FFmpeg is an exception (distro versions may be
too old to work at all or work well). For that reason you may want to use
the separately available build wrapper that first compiles FFmpeg libraries
and libass, and then compiles the player statically linked against those.