XP-REPLAY(6)XP-REPLAY(6)NAME
xp-replay - Playback an XPilot session.
SYNOPSIS
xp-replay [-help] [-scale factor] [-gamma factor] [-compress] [-ver‐
bose] inputfile
OVERVIEW
xp-replay is a program to view an XPilot recording. It takes record
files produced by xpilot(6) 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 pro‐
gram.
-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 saving 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 windows. 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 pushbuttons 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 record‐
ing. 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 nor‐
mal 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 normal 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 format.
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 sav‐
ing 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 sav‐
ing 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 specify 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 something 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 uncompressing 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 compress 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 pack‐
age, which is Copyright (C) 1989, 1991 by Jef Poskanzer.
BUG REPORTS
Bugs can be mailed to xpilot@xpilot.org.
SEE ALSOxpilot(6), xpilots(6), ppm(5), compress(1), gzip(1)
Requires X11 XP-REPLAY(6)