XP-REPLAY(Requires
NAME
xp-replay - Playback an XPilot session.
SYNOPSIS
xp-replay [-help] [-scale factor] [-gamma factor] [-com-
press] [-verbose] inputfile
OVERVIEW
xp-replay is a program to view an XPilot recording. It
takes record files produced by xpilot() and allows the
user to replay them and make snapshots of frames.
Options
-help Prints some help, including commandline
options.
-verbose Prints some information about the record
file.
-compress Save frames in compress format using the
compress program.
-scale factor Sets the scale reduction factor for saving
operations. Valid scale factors are in the
range [0.01 - 1.0].
-gamma factor Sets the gamma correction factor when sav-
ing scaled frames. Valid gamma correction
factors are in the range [0.1 - 10].
If the filename given is `-' then the standard input is
read. Frames read from the standard input are stored in
memory to allow the user to jump backward and forward
through them, however, with large record files earlier
frames may be discarded to make way for later frames. This
will mean that it may not be possible to jump back to the
start of a large recording. This restriction only affects
files read from pipes.
THE GRAPHICAL USER INTERFACE
When you start the program you will be presented two win-
dows. The first and largest window is the recording view
window where you will see the recorded game. The second
window is the control window which contains a row of push-
buttons and which shows some information about the
recorded game. A third window may be popped up giving
access to the controls to save frames.
The buttons in the control window allow you to move
through the recording. They are, from left to right:
record, rewind, reverse play, play, fast-forward, pause,
stop and eject. The symbols on them match the standard
symbols seen on tape and CD players.
Just below the buttons is information about the recording.
The position of the current frame within the recording,
the server the game was played on, the player's nickname
and username, the client that the player connected from
and the number of frames per second the server was running
at.
Playback can be in either of two modes - normal or paused.
In normal mode the recording will play back in real time
as close to the original frame rate as possible. In paused
mode, you can single step through frames.
In addition to the buttons certain keys perform shortcuts.
Buttons
Record This button pops up a window allowing you
to mark frames for recording, and to save
the marked frames in either a standard
graphics format (ppm) or in the XPilot
Record format.
Rewind In normal mode this plays the recording
backwards at 10 times normal speed. In
paused mode this button steps backward 10
frames.
Reverse play In normal mode this plays the recording
backwards. In paused mode it single steps
backward one frame.
Play In normal mode this plays the recording
forward at normal speed. In paused mode it
single steps forward 1 frame.
Fast-forward In normal mode this plays the recording
forward at 10 times normal speed. In paused
mode it steps forward 10 frames.
Pause This suspends playback and switches to
paused mode.
Stop This suspends playback and switches to nor-
mal mode.
Eject This quits the program.
Keys
f, space Step forward 1 frame.
b, delete, backspace
Step backward one frame.
z Go to frame zero.
[ Mark this as the first frame to be saved.
] Mark this as the last frame to be saved.
* Save marked frames in PPM format.
& Save marked frames in XPilot Recording for-
mat.
q Quit the program.
Recording
Either by using the keys, or the popup record window, you
can mark a section of the playback for recording. To do
that, you move to the first frame you wish to save and
mark it as the first frame. Then move to the last frame
and mark that. Then save the marked frames. When saving in
PPM format the frames will be saved in files called
xpNNNNN.ppm. Each frame wil be placed in a separate file,
and the NNNNN will be replaced by the frame number within
the original recording. When saving in XPilot Recording
format the frames will be saved in one new file called
xpN-M.xpr, where N is the frame number of the first frame
and M is the frame number of the last frame to be saved.
Since having a large number of PPM files can be quite
costly in diskspace, an option exists to automatically
shrink them whilst saving. Use the -scale option to spec-
ify a scaling factor, for example, a scale factor of 0.25
on a 768x768 recording would result in the saved frames
being 192x192. When a frame is shrunk like that, the thin
lines draw by xpilot can appear dimmed. To overcome this,
use the -gamma option with a gamma value greater than 1.
That should brighten up the saved frames. In addition a
-compress option is available to save files in compressed
format.
EXAMPLES
The simplest invocation is
xp-replay test-recording.xpr
which will play back a recording, and save frames at the
original size.
To save frames smaller that the original size use some-
thing like
xp-replay -scale 0.5 -gamma 2 test-recording.xpr
which will save frames at half size.
You may want to compress the recording files to save disk
space. You can then play them back directly without uncom-
pressing them first using
zcat test-recording.xpr.Z | xp-replay -
however, this may limit your ability to rewind through the
recording.
xp-replay automatically recognizes if a file is in com-
press format and gzip format. If this is the case then it
automatically starts compress -d or gzip -d to uncompress
the file before playback.
AUTHORS
xp-replay was originally designed and developed by Steven
Singer S.Singer@ph.surrey.ac.uk. Additional develpoment
was performed by Bert Gijsbers bert@xpilot.org.
The scaling and gamma correction code was taken from the
pbmplus package, which is Copyright (C) 1989, 1991 by Jef
Poskanzer.
BUG REPORTS
Bugs can be mailed to xpilot@xpilot.org.
SEE ALSO
xpilot() xpilots() ppm(5) compress(1) gzip(1)