Ubuntu Manpage: lavplay - Playback and edit MJPEG video

Provided by: mjpegtools_2.1.0+debian-5_amd64

NAME

       lavplay - Playback and edit MJPEG video

SYNOPSIS

       lavplay [options] lavfile1 [lavfile2 ... lavfileN]

DESCRIPTION

       lavplay  can be used to playback video in MJPEG format (either quicktime or AVI) on a zoran video-capture
       device, such as the Miro/Pinnacle DC10(+), the Iomega Buz or Linux Media Labs' LML33, or in software mode
       (using SDL).

       It also provides mechanisms for non-destructive editting video using an  interactive  front-end  such  as
       glav(1).  See SEARCHING AND EDITING below for details.

OPTIONS

lavplay accepts the following options:

-p/--playback [S|C|H]
The playback mode to be used. 'S' means software-playback using SDL.
'H' means hardware-playback on the monitor (on-screen). 'C' means hardware-playback to the
video-out of the zoran video-capture device. Obviously, 'C' and 'H' only work on computers with
zoran video-capture devices.

-Z/--full-screen
Full-screen playback. This works if SDL- or onscreen-playback is chosen.

--size NxN
Size of the video window (default: size of the input video) when using software (SDL) or hardware
onscreen playback

-a/--audio num
When play audio, 0 means never, or sum of
1: while playing forward,
2: while playing reverse,
4: even fast playing,
8: while pausing
(default: 7: forward/reverse/fast). If 8(pausing) was contained, lavplay will be very noisy, but
useful when you want to edit by sound.

-z/--zoom
Zooms the video to fit the screen as good as possible.

-x Exchange fields of an interlaced video. Try this if the video looks weird. It shouldn't be
necessary with stuff captured using lavrec(1) but could be needed for other sources.

-s/--skip num
Skip <num> seconds of video at the beginning.

-x/--exchange-fields
Invert field order (for videos which are recorded with wrong field order interlacing settings)

-F/--flicker
Disable stills flicker reduction. This is useful if you want to see stills exactly as they were
recorded rather than flicker-free!

-c/--synchronization [0|1]
Enables (1) or disables (0) the use of sync corrections. Basically, you almost certainly want
this. Disabling is really there for diagnostic purposes and not much else.

-H/--H-offset num, -V/--V-offset num
Horizontal (-H) and vertical (-V) offset when using hardware-playback. Offset plus width or
height should be smaller than or equal to the playback device's maximum allowed size (DC10+:
640x480 or 768x576, LML33/Marvel/Buz: 720x480/576).

--s-x-offset num, --s-y-offset num
Offset for the video window (from top left screen corner) when using hardware onscreen playback
in non-fullscreen mode.

--display :x.x
When using hardware fullsreen video playback (-pH), this setting can be used to specify the video
display (default: :0.0) to use for video display.

-q/--no-quit
Makes lavplay stay alive at the end of the video (lavplay won't quit). Use 'q<enter>' on the
command line to quit (see below, SEARCHING AND EDITING).

-g/--gui-mode
Enables GUI-mode. This is used by glav and Linux Video Studio. It will output the current
position in the video each frame, so that the glav or LVS can keep track of where we are in the
video which is being played back.

-P/--preserve-pathnames
This is used by glav and Linux Video Studio. When editlists are created the original pathnames
for files are used and not the canonicalised pathnames from the root directory. Useful if you've
got things like automounters active that make directories with the same non-canonical name have
different canonical names on different machines.

-U/--use-write
Use the write() system call rather than the mmap() system call for audio writing to the sound
device. This may fix some audio playback problems.

-n/--mjpeg-buffers num
Number of MJPEG-buffers. Default is 32. Try changing this number if you have many lost frames.

-v/--verbose num
Verbosity level (0, 1 or 2)

ENVIRONMENT VARIABLES

       The following environment variables can be recognized by lavrec:

       LAV_VIDEO_DEV
               The video device. Default is /dev/video

       LAV_AUDIO_DEV
               The audio device. Default is /dev/dsp

SEARCHING AND EDITING

       lavplay  can do more than simple plain playback. It is also intended to be controlled using commands sent
       via stdin from a front-end like glav(1) or similar,  more  sophisticated  tools.   The  most  significant
       aspect  of this functionality is the ability to create edit list files giving the playback sequence of an
       editted version of the input video.  The edit  list  file  can  be  read  by  any  of  the  mjpegtools(1)
       (including  lavplay!) wherever an actual video file would be acceptable.  Such edit lists record only the
       original source file and start and stop frames of the components of the  editted  video  editting  rather
       than  the  video  itself.   As  such  editting leaves the original files unchanged and requires only tiny
       amounts of data-movement.  The drawback is that for the edit list to work the original files must  remain
       unchanged,  and  that interactive play may be jumpy due to the playback sequence "skipping about" between
       different parts of the original video sequence.

       If a stand-alone consolidated versions of editted video is required it can be  produced  by  running  the
       lavtrans(1) utility on the edit list.

       Edit  list  files  are  plain  text with a very simple syntax to allow easy manual editting using a text-
       editor or writing of scripted editting tools.

STDIN COMMANDS

       The commands accepted on standard input sre as follows (and can of course be entered directly by command-
       line junkies):

       +, -    Goes to next/previous frame. Only makes sense when the video is paused.

       pN      Sets playback speed to N (N=..., -1, 0, 1, ...)

       a[01]   Enables/disables audio playback

       sN      if N is a number, this means to go to frame N. if N is prefixed by a + or -, this means to  go  N
               frames back- or forward.

       om editlist [N1 N2 [N3 N4]]
               Opens  a movie or editlist. A second and third argument can specify to only open a specific range
               of frames from this video (N1=-1 means whole video). N3  and  N4  can  specify  to  show  only  a
               specific range of frames from the frames which were just opened (useful for trimming).

       w[as] file
               Save the current editlist (a) or the current selection (s) to a file.

       q       Quit lavplay.

       e[ou] N1 N2
               Cuts (u) or copies (o) frames N1-N2 from the current editlist into an internal selection.

       ep      Pastes the contents of the selection into the current position in the editlist.

       em N1 N2 N3
               Moves frames N1-N2 to position N3 in the video.

       ed N1 N2
               Deletes frames N1-N2 from the editlist.

       ea video N1 N2 N3
               Adds  frames  N1-N2  of  the  video into position N3 within the editlist.  N1=-1 means to add the
               whole video.

       es N1 N2
               Sets the current viewable frames within the whole video to N1-N2. This is useful for trimming.

BUGS

       Editlists record absolute pathnames.  This more or less forces manual editting of the pathnames  in  them
       if it is desired to move editlists and source video files.

       lavplay  really  ought  to  make  a decent job of detecting what playback options are feasible (on-screen
       hardware, video-out port hardware, software) and set the default playback mode appropriately.   Alas,  it
       does not.

AUTHOR

       This man page was written by Ronald Bultje.
       If  you  have  questions,  remarks, problems or you just want to contact the developers, the main mailing
       list for the MJPEG-tools is:
           mjpeg-users@lists.sourceforge.net
       For more info, see our website at
           http://mjpeg.sourceforge.net/