xp-replay


     NAME
          xp-replay - Playback an XPilot session.



     SYNOPSIS
          xp-replay [-help] [-scale factor] [-gamma factor] [-
          compress] [-verbose] 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 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 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 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 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 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 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@mc.bio.uva.nl).

          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@cs.uit.no.



     SEE ALSO
          xpilot(6), xpilots(6), ppm(5), compress(1), gzip(1)