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Allows stepping back one frame via the frame_back_step inout command, bound to "," by default. This uses the precise seeking facility, and a perfect frame index built on the fly. The index is built during playback and precise seeking, and contains (as of this commit) the last 100 displayed or skipped frames. This index is used to find the PTS of the previous frame, which is then used as target for a precise seek. If no PTS is found, the core attempts to do a seek before the current frame, and skip decoded frames until the current frame is reached; this will create a sufficient index and the normal backstep algorithm can be applied. This can be rather slow. The worst case for backstepping is about the same as the worst case for precise seeking if the previous frame can be deduced from the index. If not, the worst case will be twice as slow. There's also some minor danger that the index is incorrect in case framedropping is involved. For framedropping due to --framedrop, this problem is ignored (use of --framedrop is discouraged anyway). For framedropping during precise seeking (done to make it faster), we try to not add frames to the index that are produced when this can happen. I'm not sure how well that works (or if the logic is sane), and it's sure to break with some video filters. In the worst case, backstepping might silently skip frames if you backstep after a user-initiated precise seek. (Precise seeks to do indexing are not affected.) Likewise, video filters that somehow change timing of frames and do not do this in a deterministic way (i.e. if you seek to a position, frames with different timings are produced than when the position is reached during normal playback) will make backstepping silently jump to the wrong frame. Enabling/disabling filters during playback (like for example deinterlacing) will have similar bad effects.
mpv ### Overview ======== **mpv** is a movie player based on MPlayer and mplayer2. It supports a wide variety of video file formats, audio and video codecs, and subtitle types. If you are wondering what's different from mplayer2 and MPlayer you can read more about the changes_. Compilation =========== 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. Essential dependencies (incomplete list): - gcc or clang - X development headers (xlib, X extensions, libvdpau, libGL, libXv, ...) - Audio output development headers (libasound, pulseaudio) - fribidi, freetype, fontconfig development headers (for libass) - libass - FFmpeg libraries (libavutil libavcodec libavformat libswscale libpostproc) - libjpeg - libquvi if you want to play Youtube videos directly - libx264 if you want to use encoding (has to be explicitly enabled when compiling ffmpeg) 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 (mpv-build_) that first compiles FFmpeg libraries and libass, and then compiles the player statically linked against those. If you are running Mac OSX and using homebrew we provide homebrew-mpv_, an up to date formula that compiles mpv with sensible dependencies and defaults for OSX. Bug reports =========== Please use the `issues tracker`_ provided by GitHub to send us bug reports or feature requests. Contributing ============ For small changes you can just send us pull requests through GitHub. For bigger changes come and talk to us on IRC before you start working on them. It will make code review easier for both parties later on. Contacts ======== You can find us on IRC in ``#mpv-player`` on ``irc.freenode.net`` .. _changes: https://github.com/mpv-player/mpv/blob/master/DOCS/man/en/changes.rst .. _mpv-build: https://github.com/mpv-player/mpv-build .. _homebrew-mpv: https://github.com/mpv-player/homebrew-mpv .. _issues tracker: https://github.com/mpv-player/mpv/issues