Provided by: impressive_0.12.0-2_all bug


       Impressive - presentation tool with eye candy


       impressive [OPTIONS...] FILES...


       Impressive  is  a  simple  presentation program that displays slideshows of PDF documents,
       image files or video files. Rendering is done via  OpenGL,  which  allows  for  some  "eye
       candy" effects.

       A  somewhat-modern  GPU  (graphics processing unit) supporting OpenGL 2.0 or OpenGL ES 2.0
       and appropriate drivers are required to run Impressive.


       -a <seconds> or --auto <seconds>
              Automatically advance to the next page after the given number of seconds.  Together
              with  the  -w  option  (described  below),  this  can  be  used to create automatic
              Note that this option will not interrupt video playback: If a video is longer  than
              the interval specified with --auto, it will be played until the end, but Impressive
              will change to the next page directly after that.

       -A <X>:<Y> or --aspect <X>:<Y>
              Specifies the display aspect ratio. Normally, Impressive  assumes  that  the  pixel
              aspect  ratio is 1:1 (square pixels), regardless of the display resolution that has
              been set up. If a resolution has been selected that  doesn't  match  the  display's
              aspect  ratio,  the  screen will be distorted. To overcome this, this option may be
              used to manually specify the display aspect ratio, e.g. "-A 16:9". Note  that  this
              option has no effect if the MuPDF backend is used for rendering.

       -b or --noback
              Disables  background rendering. By default, Impressive will pre-render all pages in
              a separate background thread  while  the  presentation  runs.  If  this  option  is
              specified, it will instead render all pages immediately on startup. This option has
              no effect if caching is disabled (--cache none, see below).

              Disables all functionality that relies on temporary files, specifically video frame
              extraction  using  MPlayer  (extracting  video frames with FFmpeg still works), PDF
              page title extraction, PDF hyperlinks, and even  PDF  rendering  for  all  backends
              except MuPDF 1.4 or newer on Unix-like operating systems.

       --box-edge <pixels>
              Sets  the  border  size  (in  pixels  when  unzoomed)  of  the highlight boxes' and
              spotlight's smooth edges. The default value is 4 pixels; it can be set to zero,  in
              which case highlight boxes and the spotlight will have hard edges.

       -B <ms> or --boxfade <ms>
              Sets   the  duration  (in  milliseconds)  of  the  highlight  box  fade-in/fade-out
              animation. Default value: 100 ms.

       -c <mode> or --cache <mode>
              Specifies the page cache mode to use. Valid options are:
                     Disables page caching altogether, only the current and  the  following  page
                     will  be  kept  in  RAM.  Jumping  between  pages will be very slow, because
                     Impressive will need to render the requested pages on the fly. In  addition,
                     the overview page won't be complete until every page has been shown at least
                     Caches all page images in  memory.  This  is  the  fastest  method,  but  it
                     requires  very  large  amounts  of  memory (about 3 MiB per page at 1024x768
              compressed or z
                     Caches all page images in memory as well, but in compressed form. This  will
                     be  a little slower than memory mode, but on pages with uniform backgrounds,
                     this will easily reduce the required amount of RAM by a factor of 20.
                     Like memory, but uses a temporary file rather than memory for storage.  This
                     is the default.
                     Uses  a permanent cache file for caching. This file will not be deleted when
                     Impressive quits and will be reused on subsequent invocations.  The  default
                     name  for  the  cache  file  is derived like the names for Info Scripts (see
                     below for an explanation), but with a .cache file name extension instead  of
                     .info.  This method is a little bit slower than disk mode, but the time span
                     until the overview page is fully populated will be  significantly  decreased
                     if Impressive is ran again with the same input files and options.
              The  mode  name  may  be  abbreviated at will, down to one character. Thus, --cache
              persistent, -c persist and even -cp are all synonyms.

       -C <filename>[:<X>,<Y>] or --cursor <filename>[:<X>,<Y>]
              This option can be used to specify an image that shall  be  used  as  a  (software)
              mouse  cursor  instead  of the normal (hardware) one. It can either be a name of an
              image file (typically a transparent .png) or one of the special values  "-"  (dash)
              or  "default",  both  of which select a built-in cursor image. On platforms that do
              not support a hardware cursor, this default cursor will also be used as  a  default
              if this option is not used.
              If  the  name  of  an  external file is specified, the position of the hotspot (the
              pixel inside the cursor  where  the  actual  mouse  position  is  located)  can  be
              specified as well, for example: --cursor mycursor.png:2,4.

              If  this  option  is enabled, the current time will be shown instead of the elapsed
              time if time  display  is  activated  (with  the  T  key  in  the  default  control
              configuration). Compatible with the -M option.

              This  option  will  output  a  short  help  screen of how the control configuration
              (keyboard and mouse bindings) work, along with a list of all recognized events  and
              actions  and  a dump of the current bindings (which is the default configuration if
              no other -e/--bind or -E/--controls  options  precede  this  option).  After  that,
              Impressive will exit; no presentation will be started.

       -d <time> or --duration <time>
              Specifies  the  expected  run  time  of the presentation. The time parameter can be
              either a number of seconds or a human-readable time like  1:23  (1  minute  and  23
              seconds),  4:56h  (4 hours and 56 minutes), 3m45s (3 minutes and 45 seconds), 5m (5
              minutes) or 1:23:45 (1 hour, 23 minutes and 45 seconds).
              If an expected duration is specified, Impressive will show a semi-transparent green
              progress  bar at the lower edge of the screen, indicating how much time has already
              passed. If the time is up, the bar will occupy the whole edge and  fade  to  yellow
              (at 125% of the expected time) to red (at 150% or more).

       -D <ms> or --mousedelay <ms>
              Sets  the time (in milliseconds) the mouse cursor is shown in fullscreen mode if it
              is not moved. There are two  special  values:  0  (zero)  shows  the  mouse  cursor
              permanently, 1 (one) hides it completely. The default value is 3000 ms.

       --darkness <percentage>
              Specifies  how  much  the  screen shall become darker when using highlight boxes or
              spotlight mode. The value is specified in percent, with 25  being  the  default.  A
              value  of  zero  would  mean  no darkening at all (the screen would just be blurred
              slightly, and desaturated if the graphics hardware supports it), and a value of 100
              would make everything but the highlighted parts of the screen black.

       -e <bindings> or --bind <bindings>
              Configures keyboard or mouse bindings. For the syntax of the argument, refer to the
              Control Configuration section of the manual.

       -E <filename> or --controls <filename>
              Loads a configuration file for keyboard and mouse bindings. For the syntax of these
              files, refer to the Control Configuration section of the manual.

              If  this  option is specified, Impressive will not start a normal presentation, but
              instead  enter  the  so-called  "Event  Test  Mode"  after  the  display  has  been
              initialized.  In  this  mode, Impressive will simply capture all keyboard and mouse
              events and display the name of the last event on the screen.  In  addition,  events
              will be logged to standard output. This mode helps with determining the event names
              for each key  when  creating  a  custom  control  configuration  (see  the  Control
              Configuration section).

              Sets  the window/fullscreen mode Impressive shall start up with. This option can be
              specified multiple times; each times it is found, the next of the three options  is
              selected,  in  the  follwing order: (1.)True fullscreen mode, including setting the
              video mode. This is the default mode. (2.)Windowed mode, where Impressive runs in a
              standard  window. (3.)"Fake-fullscreen" mode, where fullscreen is emulated by uding
              a window without border that fills the whole screen. Setting the display resolution
              is  not  possible in this mode. Each of these modes has a corresponding long option
              that enables it directly (--fullscreen, --windowed and --fake-fullscreen).

              Starts Impressive in fullscreen mode (the default). See the discussion  of  the  -f
              option for details.

              Starts  Impressive  in  "fake fullscreen" mode. See the discussion of the -f option
              for details.

       -F <file> or --font <file>
              Impressive uses some kind of text OSD to overlay the current page number and  title
              (if  available) on the overview page. This option can be used to specify a TrueType
              font file (.ttf) to use for the OSD. If the path specified doesn't  directly  point
              to  a useable font file, Impressive will try to search the system font directories.
              It assumes that all fonts are stored below /usr/share/fonts, /usr/local/share/fonts
              or  /usr/X11R6/lib/X11/fonts/TTF for this purpose (the latter one is useful for Mac
              OS X systems specifically). If this option is not specified, any of  DejaVuSans.ttf
              or  Vera.ttf  (the  typical  file  name  of  Bitstream Vera Sans) will be used as a

       -g <width>x<height>[+<posX>+<posY>] or --geometry <width>x<height>[+<posX>+<posY>]
              Sets the screen size or resolution Impressive shall use (in pixels).  If xrandr  is
              installed,  the  default  screen  size  for  fullscreen  mode is the current screen
              resolution; on other platforms, Impressive uses the highest resolution available to
              the  graphics system. If a standard resolution cannot be determined, the default is
              1024x768 pixels. This is also the default for windowed mode.
              Furthermore, if the additional parameters posX and posY are present,  they  specify
              the  position  of  the  upper-left corner of the window (relative to the upper-left
              corner of the desktop), in pixels,  for  windowed  and  fake-fullscreen  mode.  The
              values are ignored in "true" fullscreen mode.

       -G <gamma>[:<blacklevel>] or --gamma <gamma>[:<blacklevel>]
              Sets  up the startup gamma and (optional) black level value. The black level is the
              original image's intensity level (0...254)  that  is  to  be  mapped  to  black  in
              Impressive's output. Note that gamma and black level adjustments may be unavailable
              or constrained on some systems.

       -h or --help
              If this option is specified, Impressive writes a short command line help screen  to
              standard output and does not start a presentation.

       -H or --half-screen
              This  option  makes Impressive show the overview page and OSD elements on the right
              half of the screen only. The overview page will only show  the  left  half  of  the
              slides  as  previews.  Using  a  multi-monitor setup with a wide virtual screen and
              specially crafted slides (e.g. those that can  be  generated  with  LaTeX's  beamer
              class), this makes it possible to have presenter's notes on the second screen.
              Note  that  transitions  and  animations  are  still operating on the whole screen,
              making some of them  (like  PagePeel)  look  ugly.  Impressive  also  disables  the
              overview  zoom  animation  in  half-screen mode; it can be re-enabled by explicitly
              setting it to another value with a later command line option (--zoomtime).
              Another limitation is that the  allocation  of  the  screen  halves  (slides  left,
              overview right) is fixed.

       -i <page> or --initialpage <page>
              Specifies  the  page  number  to start with. The default value is 1 (start with the
              first page). If another value is specified, the  page  shown  by  Impressive  right
              after  initialization  is not the first one of the PDF or image list. Additionally,
              pre-rendering (if enabled) will also start at the specified page.

       -I <filename> or --script <filename>
              Overrides automatic derivation of the info script filename and specifies  a  script
              file directly.

              This option makes Impressive invert the colors of each page, turning black to white
              and vice-versa. Note that it is a full RGB inversion, so it will, for example, turn
              dark green to light purple (and vice-versa) too.

       -k or --auto-progress
              This  option  makes  Impressive  show  a  progress bar at the bottom of the screen,
              visualizing the timeout on pages that have one (either specified as a page property
              or  using the --auto command-line option). Nothing is done on pages that don't have
              a timeout.
              The progress bar shown by this option  takes  precedence  over  the  --duration  or
              --page-progress  bars:  If  one  of these options is specified as well, the timeout
              progress bar will be shown on pages with a timeout, and the other progress bar will
              be shown on pages without one.

       -l or --listtrans
              If  this  option is specified, Impressive writes a list of all available transition
              classes to standard output and does not start a presentation. Transitions that  are
              enabled by default are marked with a star (*) left of the class name.

       -L <spec> or --layout <spec>
              Specifies the OSD layout. Read below for an explanation of this option.

       --maxzoom <factor>
              The  maximum  zoom  factor  up  to  which  Impressive  shall  attempt  to  render a
              high-resolution image of the page when zoomed in.  This  can  be  any  real  number
              larger than or equal to 1.0; the default is 5.0. A setting of 1.0 causes Impressive
              to never render a high-resolution image for zooming; in this  case,  the  zoom  and
              box-zoom modes will upscale the image, but not enhance any details.
              Note  that  regardless  of  this  setting,  Impressive  always  checks the graphics
              hardware capabilities (in particular, the maximum supported texture size)  and  may
              reduce the effective value of --maxzoom if the hardware supports less than what has
              been specified.

       --min-box-size <pixels>
              This option sets the minimum size of a highlight box, in pixels. Boxes that are not
              this many pixels wide and high are rejected in order to prevent accidental creation
              of highlight boxes. The default value for this is 30 pixels.

       -M or --minutes
              If this option is set, Impressive will show the on-screen timer (activated with the
              T  key)  only  with  1  minute  resolution. By default, it will show a timer with 1
              second resolution.

              By default, Impressive uses a fragment shader to blur and desaturate the image when
              in  highlight  box  or spotlight mode. This is usually the faster and nicer-looking
              method; however, some very old hardware implementations can't deal with that shader
              and  fall  back  to  an  unusably slow software implementation. Impressive tries to
              detect scenarios where  this  would  happen  and  automatically  falls  back  to  a
              different implementation.
              There  might  be  situations where this machanism fails and Impressive tries to use
              the non-functional shader anyway. In these cases, the --noblur option can  be  used
              to enforce the fallback implementation.

       -N or --nocursor
              This  option  disables  any  display  of  a  mouse  cursor, i.e. neither the system
              ("hardware") not bitmap ("software") cursor is shown at any time.  This  is  mainly
              useful for automated presentations, where no mouse interaction is needed.

              If this option is enabled, switching to the previous or next page with the left and
              right mouse buttons is deactivated. The  keyboard  shortcuts  are  unaffected  from
              Note that this option only works as intended when the default controls are used. If
              the -e/--bind or -E/--controls options have been used, --noclicks  might  not  have
              the intended effect.

              This  option  disables the Impressive logo and version number display. Instead, the
              loading screen will be just black or, if background rendering is disabled, only the
              progress bar will be visible.

              This  option  disables  the overview page. Overview thumbnails are not created, and
              the Tab that normally  enters  overview  mode  is  ignored.  (More  precisely,  the
              overview-enter action is ignored.)

              This  option  disables  the keyboard shortcuts (Q and Esc) that could normally quit
              Impressive with a single keypress. If it is used, the only way to exit the  program
              is the key combination Alt+F4, and accidental quitting is no longer possible.
              Note  that this option only works properly if the default controls are used. If the
              -e/--bind or -E/--controls options have been used,  --noquit  might  not  have  the
              intended effect.

       -o <directory> or --output <directory>
              Do  not  display  the  presentation, but render it into a series of PNG image files
              inside the specified directory.  The  images  will  be  generated  in  the  current
              resolution as specified by the -g option. This option is useful if the presentation
              is to be given on on a foreign PC with an  old,  broken  or  otherwise  problematic
              MuPDF/Xpdf/GhostScript  installation:  By generating images of the PDF pages, is is
              made sure that no rendering bugs will happen on the target system.

       -O <mode> or --autooverview <mode>
              Enables or disables automatic derivation of whether a page shall or  shall  not  be
              shown  on  the  overview  page.  This  feature is based on the fact that some LaTeX
              presentation packages tag all pages with a title (that can be  read  by  Impressive
              with the help of pdftk), except those that contain multiple reveal steps.
              The following modes are available:
                     Disables  automatic  overview  mode. All pages will be shown on the overview
                     page by default. This is also the default setting.
                     All pages with a PDF title will be shown on the overview page.  The  purpose
                     is to show the initial state of multi-step slides on the overview page.
                     All pages before a page with a PDF title will be shown on the overview page.
                     The purpose is to show the final state of multi-step slides on the  overview
              Again,  the  mode  may be abbreviated arbitrarily, down to one character, just like
              with the -c option above..

       -p <start>-<end> or --pages <start>-<end>
              Using this option, the range of the  page  displayed  can  be  narrowed  down.  The
              presentation  will  start  at the first page in the range. All pages outside of the
              range will not be shown on the overview page and will not be cached. However,  they
              can be entered manually when cycling through the presentation. Due to the fact that
              these pages are uncached, preparation of the display will take considerably longer.

       -P <path> or --gspath <path>
              This option can be used to override the Xpdf / GhostScript path autodetection.  The
              full path to the executable of either GhostScript (gs or gs.exe) or Xpdf's pdftoppm
              utility must be specified.

       -q or --page-progress
              If this option is enabled,  Impressive  will  show  a  light-blue  semi-transparent
              progress  bar  at  the  lower edge of the screen that shows the position inside the
              presentation, i.e. the relation between the  current  page  number  and  the  total
              number  of  pages.  Note  that  this progress bar will not be shown if the duration
              progress bar (-d option) is also enabled.

       -Q or --autoquit
              If this option is specified, Impressive quits automatically when trying to navigate
              to the page after the last page or the page before the first page.
              This option does not have any effect if --wrap is used.

       -r <n> or --rotate <n>
              Display  all pages rotated by nx90 degrees clockwise. Try -r 1 or -r 3 if there are
              problems with PDFs generated by LaTeX on some Xpdf or GhostScript versions.

       -s or --scale (image input only)
              If a directory with image files is used as input, Impressive will scale down images
              that  are  too  big  for  the  screen. But by default, it will not scale up smaller
              images to fit the screen; it  will  leave  a  black  border  instead.  This  option
              overrides this setting and enables upscaling of smaller images.

       -s or --supersample (PDF input only)
              This  switch  enables  antialiasing  by  4x  supersampling  instead  of  the normal
              multisampling method used by Xpdf or GhostScript. While this usually degrades  both
              visual  quality and performance, it may be necessary for circumventing white strips
              or moire-like patterns in gradients.

       -S <pixels> or --fontsize <pixels>
              This option sets the size, in pixels, of the OSD font. The default value is 14.

       --spot-radius <pixels>
              This option sets the initial radius of the spotlight, in pixels. The default  value
              is 64.

              This  option  enables display of the elapsed presentation time, as if the T key has
              been pressed immediately after startup. This implies time tracking mode (--tracking

       -t <ms> or --transition <trans1[,trans2...]>
              Using  this  switch,  the  set of transitions Impressive will randomly draw at page
              changes can be specified. If only one transition class  is  specified,  this  class
              will  be used for all pages that do not have another transition explicitly assigned
              in their page properties. Multiple transitions have to be separated by commas; they
              will  be used in random order. The -l option can be used to get a list of available

       -T <ms> or --transtime <ms>
              Sets the  duration  (in  milliseconds)  of  page  transitions.  0  (zero)  disables
              transitions altogether. Default value: 1000 ms.

              This option enables time tracking mode. In this mode, a report of all pages visited
              with their display duration, enter and leave times  will  be  written  to  standard
              output. This can be very useful when preparing presentations.

       -u <seconds> or --poll <seconds>
              If  this  option  is  specified,  the  source file or directory will be checked for
              changes regularly. If a change in the input PDF file or any of the image  files  in
              the  input  image  directory  is  detected,  the page cache will be flushed and the
              current page as well as the info  script  will  be  reloaded.  The  current  page's
              transition will be shown between the old and the new version of the page.
              The  new  PDF file must have at least as much pages as the old one; also, it should
              have the same aspect ratio. If the input is a directory, image files must not  have

       -v or --verbose
              This  option  makes  Impressive  more  verbose,  i.e.  it  will print slightly more
              informational messages than usual.

       -V <pixels> or --overscan <pixels>
              PDF files often contain tiny amounts of white borders around the edges  which  look
              bad in screen presentations. To eliminate this problem, Impressive uses "overscan":
              PDF files will not be rendered to fit the screen size exactly,  but  they  will  be
              rendered a bit larger so that the (possibly broken) borders can be cropped off. The
              amount of overscan, in screen pixels, can be set  with  this  option.  The  default
              value is 3 pixels, which should remove borders in most presentations at most common
              screen resolutions without cropping the pages too much.

       -w or --wrap
              If this option is set, Impressive will "wrap" over to the first page after the last
              page.  In  other  words,  advancing to the next page at the end of the presentation
              will restart the whole presentation.

       -W or --nowheel
              By default, it is possible to change pages  using  the  mouse  wheel.  This  option
              disables this behavior, which can be useful to prevent spurious page changes if the
              mouse wheel is likely to be moved by accident. In addition, it makes it possible to
              enter zoom mode with the mouse wheel.
              Note  that this option only works properly if the default controls are used. If the
              -e/--bind or -E/--controls options have been used, --nowheel  might  not  have  the
              intended effect.

              Starts  Impressive  in  windowed  mode.  See  the  discussion  of the -f option for

       -x or --fade
              This option enables a smooth fade-in effect at the start of the presentation and  a
              fade-out effect just before Impressive quits.

       -X or --shuffle
              If  this  option  is  enabled,  the  input files will be shuffled into random order
              before starting the presentation. The individual pages of PDF input files will stay
              in  their  original  order,  though,  so  this  option  is  mainly useful for image

       -y or --auto-auto
              This option can be used together with --duration to have Impressive compute a  page
              timeout  (as  with the --auto option) automatically. This results in a presentation
              that runs automatically, displaying each slide for  the  same  time,  so  that  the
              desired  total  duration  will  be  reached  (almost) exactly. One exception is the
              runtime of videos, which is not taken into account.

       --zbox-edge <pixels>
              Sets the border size (in pixels when unzoomed) of the box-zoom boxes' smooth edges.
              The  default  value  is  1 pixel; it can be set to zero, in which case the box-zoom
              area will have a hard edge.

       -z <factor> or --zoom <factor>
              Sets the scaling factor that is used in zoom mode. It can be any real  value  above
              1.0;  the  default  value  is  2.0.  Note  that  it  might  not  be possible to get
              high-quality  zooming  for  large  zoom  factors  due  to  hardware   restrictions.
              Furthermore, please be aware that after leaving zoom mode, the image quality of the
              normal page display may be slightly degraded until another page is displayed  if  a
              zoom factor other than 2.0 is used.

       --zoomdarkness <percentage>
              Specifies  how  much  the  non-selected  parts of the screen shall become darker in
              box-zoom mode. The value is specified in percent, with  90  being  the  default.  A
              value  of  zero would mean no darkening at all (parts outside of the zoom box would
              still be perfectly visible), and a value of  100  would  make  everything  but  the
              selected region black.

       -Z <ms> or --zoomtime <ms>
              Sets  the duration (in milliseconds) of the overview page zoom-in/zoom-out effects.
              Default value: 250 ms.

       --cachefile <filename>
              Activates persistent cache mode and specifies the name of the cache file to use.


       Following the options, the input file name(s) must be specified. Recognized file types are
       PDF,  image files (JPEG, PNG, TIFF, BMP, PGM/PPM) and video files (AVI, MOV/MP4, MKV/WebM,
       OGV, MPEG, M2TS, FLV). If the name of  a  directory  is  put  on  the  command  line,  all
       recognized  image  files  (no PDF files!) in this directory will be played in alphanumeric
       order (case-insensitive).

       In addition, Impressive can use a text file containing a list of files or  directories  to
       show:  This text file must contain at most one file name per line; every character after a
       hash sign (#) is treated as a comment and will be ignored. If such a comment is put on the
       same line as an image file name, it will be used as the page's title. List file names must
       be prefixed with an at sign (@) on the command line, e.g. impressive @my_list_file.

       Impressive will also expand wild-card characters (* and ?) if this isn't already  done  by
       the  shell, but apart from that, it will not reorder the arguments. Thus, it will show the
       documents in the order specified at the command line.

       If video files are specified on the command line, Impressive generates presentation  pages
       for  them  just like it does for image files. If FFmpeg or MPlayer are installed, the page
       will be shown as a screenshot of the first video frame. When entering  such  a  page,  the
       video  will be played back if a suitable player (MPlayer, or omxplayer on Raspberry Pi) is

       The OSD layout option (-L/--layout) accepts a string with comma-separated key=value pairs.
       The following keywords are recognized:
              The  opacity of the OSD text, either as a floating-point value between 0 and 1 or a
              percentage between 2 and 100.
              The distance (in pixels) of the OSD text to the screen borders.
              The position of the timer.
              The position of the page title in overview mode.
              The position of the page number in overview mode.
              The position of the status line.
       The position specifications are composed by one character that indicates whether the  text
       shall  be displayed at the top (T) or bottom (B) edge of the screen and one character that
       indicates whether it shall appear on the left (L), on the right (R) or centered (C).

       For example, the default OSD layout equals the following option string:
           -L margin=16,alpha=1,time=TR,title=BL,page=BR,status=TL

       The following examples illustrate some typical command lines. They assume that  Impressive
       can  be run by simply typing "impressive" on the command line. Depending on how Impressive
       is installed, this has to be substituted with the  actual  way  to  run  Impressive  (e.g.
       "python  ~/impressive/"  for a fresh SVN checkout). Furthermore, the file
       "demo.pdf" is used as the document to show here; obviously this has to be replaced by  the
       path to the actual PDF file too.

       In  the simplest case, Impressive is run directly with the name of the file to show and no
       further parameters. This will start a full-screen presentation with all settings at  their
           impressive demo.pdf

       To  just  quickly  check  a  slide  deck, it might make sense to run Impressive in a small
       window and not full-screen. This can be done with something like
           impressive -f -g 800x600 demo.pdf

       Impressive can also be used in digital signage scenarios, like displays  in  shop  windows
       with  a permanent slideshow. This can be achieved by having Impressive advance to the next
       page automatically after a specified time (e.g. 10 seconds) and re-start the  presentation
       from the start after the last slide:
           impressive -a 10 -w demo.pdf


       On startup, Impressive will display a black screen with the program logo at the center. If
       caching is enabled, but background rendering is disabled, all pages  of  the  presentation
       will then be rendered once. A bar in the lower half of the screen displays the progress of
       this operation. Any key or mouse click (except for those that quit Impressive, typically Q
       and  Esc)  skips  this  process, with the effect that Impressive will render the remaining
       pages on demand. Please note that the overview page will not be complete until every  page
       has  been  rendered  at least once. In other words, if the precaching process was skipped,
       placeholders will be displayed for all pages that have not been rendered yet. By  default,
       Impressive  will  build  up the cache in the background while the presentation runs. Thus,
       the progress bar will not appear and the preparation will only take  the  amount  of  time
       required  to  render  the  first  two pages of the presentation. After this initialization
       process, Impressive will switch to the first page directly and without any transition.


       The keyboard and mouse controls  used  by  Impressive  are  configurable  (with  very  few
       exceptions). The default controls are as follows:

       Esc key
              Return from the currently active special mode (zoom, box-zoom, overview, spotlight,
              highlight boxes); if no such special mode is active, quit Impressive altogether.

       Q key or Alt+F4
              Quit Impressive immediately.

       LMB (left mouse button), mouse wheel down, Page Down key, Cursor Down  key,  Cursor  Right
       key or Spacebar
              Go to the next page (using a transition).

       RMB  (right  mouse button), mouse wheel up, Page Up key, Cursor Up key, Cursor Left key or
       Backspace key
              Go to the previous page (using a transition).

       Home key / End key
              Go directly to the first or last page of the presentation.

       Ctrl key (modifier)
              If one of the page navigation keys (Page Up/Down, Cursor  keys,  Space,  Backspace,
              Home, End) is pressed while the Ctrl key is held down, the destination page will be
              entered immediately, without a transition.

       L key
              Return to the last (most recently displayed) page. This can be used to toggle  back
              and forth between two pages.

       F key
              Toggle fullscreen mode.

       Tab key
              Zoom back to the overview page. While in overview mode, a page can be selected with
              the mouse and activated with the left mouse  button.  The  right  or  middle  mouse
              button or the Tab key leave overview mode without changing the current page.

       MMB (middle mouse button)
              In  normal  display mode, this acts like the Tab key: it zooms back to the overview
              page. If the page is zoomed in, it will return to normal mode.

       LMB over a PDF hyperlink
              Jump to the  page  referenced  by  the  hyperlink.  Two  types  of  hyperlinks  are
              supported:  Links  that  point  to  some  other  page of the same document, and URL
              hyperlinks like Web links and e-mail addresses. This feature is only  available  if
              pdftk is installed. Furthermore, xdg-open from the Portland project
              is required for URL links to work.  Please note that the hyperlink feature will not
              work properly when pages are rotated.

       click&drag with LMB (left mouse button)
              Create  a  new  highlight  box.  While at least one highlight box is defined on the
              current page, the page itself will be shown in a darker, blurry and  (if  supported
              by  the  graphics hardware) desaturated rendition. Only the highlight boxes will be
              displayed in their original lightness, sharpness and color saturation.
              If a page with highlight boxes is left, the boxes will be saved  and  restored  the
              next time this page is shown again.

       click&drag with Ctrl+LMB (left mouse button)
              Draw  a box to zoom into. This enters so-called "box-zoom" mode, where the selected
              region is zoomed into full view and anything  else  is  displayed  in  much  darker
              colors  (but  not  blurred  like  in highlight box mode). The page contents will be
              re-rendered in  a  higher  resolution,  if  possible  (limited  to  what  has  been
              configured  with  the  --maxzoom  command-line  option, and the graphics hardware's
              maximum supported texture size). To leave this mode again, use RMB, MMB or Esc.
              Note that box-zoom  mode  is  mutually  exclusive  with  highlight  boxes  and  the
              spotlight;  if  any  of those is currently active, it's not possible to draw a zoom

       RMB (right mouse button) over a highlight box
              If the right mouse button is clicked while the mouse cursor is  above  a  highlight
              box,  the  box will be removed. If the last box on a page is removed, the page will
              turn bright and sharp again.

       S key
              Save the info script associated with the current presentation. The main purpose for
              this  is to permanently save highlight boxes or keyboard shortcuts, so they will be
              restored the next time this presentation is started.

       T key
              Activate or deactivate the time display at the upper-right corner of the screen. If
              the  timer  is activated while the very first page of the presentation is shown, it
              activates time tracking mode, just as if the  command-line  option  --tracking  had
              been specified.

       R key
              Reset the presentation timer.

       C key
              Removes ("clears") all highlight boxes from the current page.

       Return key or Enter key
              Toggle  spotlight  mode.  In  this mode, the page is darkened in the same way as if
              highlight boxes are present, but instead of  (or  in  addition  to)  the  boxes,  a
              circular  "spotlight"  will  be  shown  around the mouse cursor position, following
              every motion of the mouse cursor.

       + / - key, 9 / 0 key or mouse wheel in spotlight mode
              Adjust the spotlight radius.

       Ctrl+9 or Ctrl+0 keys
              Resets the spotlight radius to the default value, i.e. the value that has been  set
              up   by  the  radius  page  property,  the  --spot-radius  command-line  option  or
              Impressive's built-in default.

       7 / 8 key
              Adjust the amount of darkening applied to the page in spotlight, highlight  box  or
              box-zoom mode.

       Ctrl+7 or Ctrl+8 keys
              Resets the amount of darkening in spotlight, highlight box and box-zoom mode to the
              default values, i.e.  the  value  that  have  been  set  up  by  the  darkness  and
              zoomdarkness  page  properties,  the  --darkness  and  --zoomdarkness  command-line
              options or Impressive's built-in defaults.

       Z key
              Toggle zoom mode. When this key is first pressed, the current page  will  zoom  in.
              The  page will be displayed at double size, but in its original resolution (i.e. it
              will be blurry). Impressive will re-render the page at the new  resolution  if  the
              graphics  hardware  supports  it.  During this time, Impressive will not accept any
              input, so don't even think about clicking the mouse or  pressing  keys  before  the
              image gets crisp again.
              In  zoom  mode,  all other functions will work as normal. Any operations that leave
              the current page, such as flipping the page or entering the overview  screen,  will
              leave zoom mode, too.

       [ / ] key
              Adjust the gamma value of the display (might not be supported on every hardware).

       { / } key
              Adjust the black level of the display (might not be supported on every hardware).

       \ key
              Revert gamma and black level back to normal.

       O key
              This  will  toggle  the  "visible  on  overview page" flag of the current page. The
              result will not be visible immediately, but it can be  saved  to  the  info  script
              (using the S key) and will be in effect the next time the presentation is started.

       I key
              This  will  toggle the skip flag of the current page. A page marked as skipped will
              not be reachable with the normal forward/backward navigation keys.

       B / W key or . (dot) / , (comma) key
              Fade to black or white, respectively. This feature can be used if a  whiteboard  or
              blackboard  in  front of the projection area is to be used during the presentation.
              Using these two keys, the screen will fade into a solid color. On any  keypress  or
              mouse  click, it will fade back to normal. These keys are not available in overview

       click&drag with MMB (middle mouse button) or RMB (right mouse button) in zoom mode
              Move the visible part of the page in zoom mode.

       mouse wheel up / down in zoom mode, U key
              Zoom a bit in or out. When zoomed out fully, zoom mode is left; note  that  in  the
              default  configuration, this means that when trying to zoom out even more using the
              wheel, the page is left instead. This is different if the  -W/--nowheel  option  is
              used,  where  page  navigation  using the mouse wheel is disabled, and the wheel is
              always used for zooming. In this mode, the wheel can also be  used  to  enter  zoom
              mode in the first place.
              Note  that  changing  the  zoom  level  on  the  fly  with  the wheel does not make
              Impressive automatically re-render the page at a higher resolution to increase  the
              level  of  detail.  To  do  this,  the  U key needs to be pressed manually when the
              desired zoom level has been set up.

       Cursor keys in overview mode
              Navigate through pages.

       Alt+Tab keys
              If Impressive is in fullscreen mode, the window will be  minimized  so  that  other
              applications can be used.

       Any  alphanumeric  (A-z,  0-9)  or  function  key (F1-F12) that is not bound to a specific
       action mentioned above or configured by the  user  (see  below)  can  be  used  to  assign
       shortcuts  to pages that require quick access. If one of the keys is pressed together with
       Shift, the currently displayed page is associated with this key. To recall the page later,
       it is sufficient to press the shortcut key again. Shortcuts can be stored permanently with
       the S key.


       As already mentioned  in  the  previous  chapter,  the  keyboard  and  mouse  bindings  of
       Impressive  can  be  widely configured. The only exceptions are the Alt+F4 and Alt+Tab key
       combinations that will always quit or minimize Impressive,  respectively.  For  everything
       else,  there  is  a versatile configuration system in place; the controls described in the
       previous section are merely the defaults.

       Impressive's control system works by associating events with actions. An event is a key on
       the  keyboard,  a  mouse  button or a mouse wheel movement. An action is something that is
       performed by Impressive as a result of an event, like going to the next page, switching to
       overview  mode  or  quitting  the  program. The association of an event to an an action is
       called a binding. Multiple events can be bound to the same action (like the page down  and
       space  keys  in  the  default  setting,  both  of which go to the next page); furthermore,
       multiple actions can be bound to the same event. In fact, bindings do not associate events
       with single actions at all, but with chains of actions. Only the first action in the chain
       that matches (i.e. makes sense in) the current context  will  be  executed  if  the  event
       fires;  all  other  actions  will  be  ignored.  If  no  action matches, no action will be
       performed and the event will be ignored.

       One example of such an action chain is the default binding  for  the  left  mouse  button,
       which  draws a highlight box if the mouse cursor moved, or visits a hyperlink if the mouse
       cursor hovers over one, or goes to the next page if none of the other conditions are met.

       Both events and actions have mnemonic names that are used in the command-line options  and
       configuration  files  used  for setting up bindings. Event and actions names are generally
       case-insensitive, though the canonical notation is lowercase.
       If an event or action specified on the command line or in  a  configuration  file  is  not
       recognized  by  Impressive,  an  error  message  will  be  written  to the console and the
       offending event or action will be ignored. Errors in control configuration are thus always

       Keyboard events are generally named after the keys they refer to. Consequently, the events
       a to z and 0 to 9 mean the respective letter and number keys on the main keyboard,  f1  to
       f12  are the function keys and kp0 to kp9 are the number keys on the numerical keypad. All
       of these are raw scancodes, which has two implications:  First,  the  key  names  are  not
       internationalized  and  refer  to  the  US  keyboard layout (e.g. the Z key on a German or
       French keyboard will actually react to the event name y or w); second, modifiers  will  be
       ignored as well (e.g. the numerical keypad will always generate the kpX scancodes, even if
       Num Lock is off).

       The mnemonic names for the other keyboard events are as  follows  (in  alphabetic  order):
       ampersand,  asterisk,  at, backquote, backslash, backspace, break, capslock, caret, clear,
       comma, down, end, escape, euro, exclaim, greater, hash,  help,  home,  insert,  kp_divide,
       kp_enter,   kp_equals,     kp_minus,   kp_multiply,  kp_plus,  lalt,  last,  lctrl,  left,
       leftbracket, leftparen, less, lmeta, lshift, lsuper, menu, minus, mode, numlock, pagedown,
       pageup, pause, period, plus, power, print, question, quote, quotedbl, ralt, rctrl, return,
       right, rightbracket, rightparen,  rmeta,  rshift,  rsuper,  scrollock,  semicolon,  slash,
       space,  sysreq,  tab,  underscore,  up.  The events prefixed with kp_ refer to keys on the
       numerical keypad. Other than that, the names should be  reasonably  descriptive,  so  they
       will not be described futher at this point. Also note that not all keyboards and platforms
       support the full range of keys defined in this list.

       Mouse event names are mapped as follows:

              the left mouse button

              the middle mouse button

              the right mouse button

              scrolling the mouse wheel upwards

              scrolling the mouse wheel downwards

       btnX (i.e. btn6, btn7, ...)
              additional mouse buttons, the mapping of which is device-specific; use --evtest  to
              see which button is which

       The  event  names  can be prefixed with the three modifiers ctrl+, alt+ and shift+ to make
       the event valid only if the specified set of modifiers is pressed as well. This works  for
       both  keyboard  and  mouse  events. Multiple modifiers can be combined, but the order must
       match the one mentioned in this paragraph. For example,  ctrl+shift+x  is  a  valid  event
       name, while shift+ctrl+x is not.

       A  simple  way to determine the name associated with an event is using Impressive's "Event
       Test Mode" by invoking impressive --evtest. In this mode, the name of each incoming  event
       will  be  displayed on the screen (and logged to standard output), which makes it possible
       to determine event names by experimentation.

       The following list describes all  actions  supported  by  Impressive,  together  with  the
       conditions  under which they will match. Note that most actions will not match in overview
       mode and during video playback, unless mentioned otherwise in the description.

              Draw a highlight box if the mouse has been moved since the button has been  pressed
              down. This action must only be bound to a mouse button event, otherwise it will not
              function properly.

              Removes all boxes from the current page.

              Removes the highlight box under the mouse cursor, if there is any.

              Define a region to zoom into by drawing a rectangle. This action must only be bound
              to a mouse button event, otherwise it will not function properly.

              If in box-zoom (but not normal zoom) mode, leave box-zoom mode.

       fade-less, fade-more
              Decrease or increase the amount of darkening applied to the background in spotlight
              or highlight box mode.

              Resets the background darkness in spotlight or highlight box mode  to  its  default

       fade-to-black, fade-to-white
              Fades  to  a  black or white screen. Once the screen is faded out, any event except
              those bound to the quit action will just  leave  fade  mode  and  not  perform  its
              assigned action.

              Toggle fullscreen mode on platforms that support it.

       gamma-decrease, gamma-increase
              Decrease  or  increase the gamma level (i.e. roughly the brightness) of the display
              on platforms that support it.

       gamma-bl-decrease, gamma-bl-increase
              Decrease or increase the black level of the display on platforms that support it.

              Reset the gamma and black level settings to their defaults.

       goto-end, goto-end-notrans
              Go to the last page of the presentation, with or without a transition.

       goto-last, goto-last-notrans
              Go to the last (i.e. most recently) visited page, with or without a transition.

       goto-next, goto-next-notrans
              Go to the following page of the presentation, with or without a transition.

       goto-prev, goto-prev-notrans
              Go to the previous page of the presentation, with or without a transition.

       goto-start, goto-start-notrans
              Go to the first page of the presentation, with or without a transition.

       hyperlink, hyperlink-notrans
              Navigate to the hyperlink under the mouse cursor, if there is one. If the hyperlink
              is  a  reference  to  another page of the presentation, this page will be activated
              with or without a transition. If the hyperlink refers to an external  object  (e.g.
              an URL), it will be opened externally, if supported by the system.

              When in overview mode, confirm the selection and leave overview mode, navigating to
              the selected page.

       overview-down, overview-up
              When in overview mode, select the page above or below the currently selected one in
              the grid.

              When not in overview mode, zoom out of the current page, entering overview mode.

              When  in overview mode, leave overview mode, zooming back to the page that has been
              displayed before entering overview mode.

       overview-next, overview-prev
              When in overview mode, select the following or previous page.

              Quits Impressive immediately. This action is available in all modes.

              Save or update the Info Script for the current presentation.

              If spotlight mode is not active, enable spotlight mode.

              If spotlight mode is active, deactivate spotlight mode.

       spotlight-grow, spotlight-shrink
              When in spotlight mode, increase or decrease the radius of the spotlight.

              When in spotlight mode, reset the spotlight radius to the default value.

              Reset the presentation timer.

              Toggle on-screen display of the current presentation time, or  wall-clock  time  if
              the  --clock  option  is  used.  If  this is done at the start of the presentation,
              before the first page has been left, time tracking mode will be enabled,  like  the
              --tracking option would have done.

              This  toggles  the  "page is visible on overview screen" flag for the current page.
              This will not have an immediate effect, but it can be saved to an Info Script.

              This toggles the "skip page when navigating with goto-prev and goto-next" flag  for
              the current page.

              In video playback mode, this pauses or unpauses playback.

       video-seek-backward-10, video-seek-backward-1, video-seek-forward-1, video-seek-forward-10
              In video playback mode, seek forward or backward by 1 or 10 seconds.

              In video playback mode, if playback is paused, advance one frame in the video.

              In video playback mode, stop playback and return to normal page display mode.

              If  not  in  zoom mode, enter zoom mode with the zoom level configured with the -z/
              --zoom option.

              If in zoom or box-zoom mode, leave that mode.

       zoom-in, zoom-out
              Slightly increase or decrease the current zoom level.  This  does  not  change  the
              page's  rendering  resolution,  it  only zooms the visible part of the screen in or
              out, centered around the mouse cursor's position. Zoom mode is  left  automatically
              if the zoom level goes to down to 1x; conversely, zoom mode is entered when calling
              zoom-in while zoom mode is not active.

              If in zoom mode, the visible area of the page can be moved around  with  the  mouse
              while the key or mouse button of the associated event is held down.

              If  in  zoom  mode,  re-render  the current page in a resolution that best fits the
              current zoom level, up to the limits of the  graphics  hardware  or  the  --maxzoom
              setting.  This  only  needs  to  be  done  explicitly when zooming with the zoom-in
              action; zoom-enter and box-zoom do this automatically.

       The arguments of the -e/--bind command-line option have the following basic syntax:
           <event> [,<event2>...] <operator> <action> [,<action2>...]
       In other words, it is a sequence of  event  names  joined  with  commas,  followed  by  an
       operator  (see  below)  and  a  sequence of action names joined with commas. Multiple such
       binding statements can be combined into one argument by joining them with a semicolon (;).

       The used operator defines in which way the action list shall modify the  bindings  of  the
       referenced events:

       = (equals sign), += (plus sign and equals sign)
              The  specified  actions  will  be added to the bindings of the specified events. In
              other  words,  event=action1,action2  does  exactly  the  same  as   event=action1;

       := (colon and equals sign)
              The specified actions will replace the bindings of the specified events.

       -= (minus sign and equals sign)
              The  specified  actions  will be removed from the bindings of the specified events.
              For example, to make the Esc key in the default bindings not clear highlight boxes,
              but otherwise preserve its original functionality, escape -= box-clear can be used.

       Other than bindings, a statement can also contain one of the following special commands:

              Clears all current bindings.

              Discards all current bindings and (re-)establishes the default bindings.

       include <filename>
              Loads and executes a control configuration file with a specified name.

       The  syntax  for  the  configuration  files  used with the -E/--controls option or include
       statement is exactly the  same  as  for  the  ad-hoc  configuration  option,  except  that
       individual bindings can be written on individual lines instead of joining them together to
       a single long line with semicolons. In addition, everything following a hash sign (#) on a
       line will be ignored as a comment.

       One  practical  example  for such a configuration file can be the following: The author of
       this program uses a cheap presentation remote control device that has  four  cursor  keys,
       one  "enter"  key  and  a slider that switches between keyboard and mouse mode. Mouse mode
       works as expected, but what it does in keyboard mode is quite peculiar: the  up  and  down
       keys  act  like  Page-Up  and  Page-Down keys on a keyboard, the right arrow key sends the
       letter B to the computer, and the left key toggles between  Esc  and  F5  each  time  it's
       pressed.  The  following configuration file allows basic navigation and access to overview
       mode with this device:

             clearall  # don't use the default bindings
             lmb = quit  # quit Impressive by clicking in mouse mode
             # everything else uses keyboard mode:
             return = overview-enter, overview-confirm  # toggle overview mode
             escape, f5 = overview-prev, goto-prev
             b = overview-next, goto-next
             pageup = overview-up, goto-prev
             pagedown = overview-down, goto-next

       To get a better idea of how the control  configuration  system  works  in  practice,  it's
       recommended  to  study  the  output  of  impressive --control-help - this not only gives a
       concise overview of all events and actions, but also a full dump of  Impressive's  default
       bindings that can be used as a starting point for own customizations.


       Impressive  offers  a  powerful  way to customize individual presentations using so-called
       info scripts. An info script is a text file having the same name and located in  the  same
       directory as the presentation file itself, except for the additional suffix .info. Thus, a
       presentation file called BrandNewProduct.pdf would  have  a  info  script  with  the  name  If  multiple  arguments were specified on the command line, the
       info script will be called just .info (a dot file, so to speak). If a directory  name  was
       specified  as  the only argument, either a file called or a file called
       .info inside the directory will be  used,  depending  on  whether  a  path  separator  was
       specified  at  the  end  of the directory name or not - Impressive simply appends .info to
       whatever the input path name was.
       In any case, the default file name can be overridden by the -I command line option.

       Info scripts are actually Python scripts with full  access  to  Impressive's  global  data
       structures  and  functions.  (It  is possible to write real interactive applications using
       info scripts.) Thus, they can modify a broad range of settings concerning Impressive. This
       manual will only cover the most basic ones.

       The  main  part  of an info script defines the properties of each page. At the moment, the
       following properties are defined:

              Each page can have a title that is displayed in the Impressive window's title  bar.
              If there is no title explicitly specified in the info script, the title of the page
              will be extracted from PDF metadata if pdftk is installed, or the image  file  name
              will be used if the presentation is an image slideshow.

              With this property, the transition class to be used for rendering the transition to
              this page (i.e. between the previous page and this  page)  can  be  specified.  For
              pages lacking this property, random transitions will be chosen. A list of available
              transition classes can be obtained with impressive -l.

              This property overrides the global transition time parameter  (-T  at  the  command
              line).  It  contains the integer time (in milliseconds) the transition to this page
              shall take.

              This property holds a boolean value (0/False or 1/True) that specifies whether  the
              page  shall  be included in the overview page. If this property isn't specified, it
              is assumed to be True.

              This boolean property can be set to 1/True if the page shall be skipped during  the
              Pages with overview:True, skip:False will be accessible both by cycling through the
              pages and using the overview page,
              pages with overview:True, skip:True will be silently skipped  in  the  normal  page
              cycle, but remain accessible from the overview page,
              pages  with  overview:False, skip:False will appear in the normal cycle, but not on
              the overview page
              and pages with overview:False, skip:True will not be accessible at all.

              This property stores a list of highlight box coordinates.  Normally,  there  is  no
              need to edit this by hand, as Impressive handles this automatically if the S key is

              If  a  timeout  property  is  present  and  the  page  is  shown,  Impressive  will
              automatically  switch  to the next page after the specified number of milliseconds.
              Normally, the timeout will only be effective the  first  time  the  page  is  shown
              unless wrap mode is used (command-line option -w or --wrap). This restriction makes
              it possible to create self-running presentations with individual per-page timeouts.

              This property takes an integer value that, if defined, will be used to  set  a  new
              spotlight radius every time the page is entered. This overrides the current setting
              as defined by the --spot-radius command line option or run-time  adjustments.  Note
              that  the  value  is  not  reset  to the default value after the page has been left

              This property takes an integer or floating-point percentage value that, if defined,
              will be used to set the background darkness in spotlight or highlight box mode each
              time the page is entered. This overrides the current  setting  as  defined  by  the
              --darkness  command line option or run-time adjustments. Note that the value is not
              reset to the default value after the page has been left again.

              This property takes an integer or floating-point percentage value that, if defined,
              will  be used to set the background darkness in box-zoom mode each time the page is
              entered. This overrides the  current  setting  as  defined  by  the  --zoomdarkness
              command  line  option  or run-time adjustments. Note that the value is not reset to
              the default value after the page has been left again.

              This property can hold a string with a single line of text that will  be  displayed
              on screen while the page is shown. Display of this text can not be disabled.

              Specifies the file name of a sound file to be played (via MPlayer) when the page is
              first entered. Once started, the sound will be played until  its  end  is  reached,
              another sound or video is played, or Impressive is exited.

              Specifies  the  file  name  of  a  video  file  to be played when the page is first
              entered. The video will be displayed full-screen. Any  key  or  mouse  click  stops
              playback,  except  the  cursor  keys, which are used to seek in the video file, and
              space, which can be used to pause playback.
              Please not that this function is still somewhat experimental. It uses  an  external
              player  application  (MPlayer,  or omxplayer on Raspberry Pi) to perform the actual
              playback, and embeds it into Impressive's window.

              If this property is present and set to 1 or True, the media file specified  in  the
              sound  or  video properties will be played every time the page is entered, not just
              the first time.

              If this property is set to zero, the presentation progress bar  (which  is  usually
              set  up with the -d/--duration command line switch) will not be shown on this page.
              In practice, it might be useful to hide the bar from the first page so that  it  is
              not visible during the introduction.

              If  this  property is set to 1 or True, the timer will be reset each time this page
              is left, just as if the R has been pressed. If the special value 2 or FirstTimeOnly
              is  used,  the reset will only take place if the page was shown for the first time.
              Again,  this  is  particularly  useful  on  the  first  page:  A   combination   of
              progress:False,  reset:FirstTimeOnly  makes  it possible to set up the presentation
              long before it actually begins - the first page can be showed as long  as  desired,
              actual timing starts at the second page.

              This  property  is  a  per-page  override  of the global -r command line option: It
              specifies how the page shall be rotated, in 90-degree steps clockwise.

       OnEnter, OnLeave, OnEnterOnce, OnLeaveOnce
              These properties can contain a Python callable (i.e. a function reference or lambda
              expression)  that  is executed when the page is entered or left. The ~Once variants
              will only be executed when the page is entered or left  for  the  first  time.  The
              callable  must  not  take  any  arguments.  This  feature  can be used to associate
              arbitrary Python  code  with  specific  pages,  for  example  to  execute  external
              Warning:  Lambda  expressions  cannot be properly processed by the Info Script save
              function (S key). If Impressive encounters lambda expressions when saving, it  will
              remove  them.  In  addition,  it  will  not overwrite the original info script, but
              generate an extra file that needs to be merged withe the original script by hand.

              This property can be assigned a dictionary that maps alphanumerical keys to  Python
              functions. For example, 'keys': { 'x': SomeFunction } will invoke SomeFunction() if
              the lowercase character 'x' is typed while the page  is  displayed.  Regarding  the
              functions,  the  same  restrictions  as  for  the OnEnter/OnLeave family apply: the
              function must not take any parameters and lambda functions can not be  saved.  Also
              note  that  it  is  not possible to overwrite Impressive's pre-defined key bindings
              with this method.

              This property specifies whether the colors of that page shall be  inverted  in  the
              same  way  the --invert command-line switch does. It overrides the --invert setting
              on a per-page basis: If set to True, the page will always be inverted;  if  set  to
              False,  the  page will never be inverted even if --invert has been specified on the
              command line.

       Note that in Impressive versions prior to 0.11.0, the transition and transtime  properties
       defined  the  transition  from the current page to the next, not from the previous page to
       the current one.

       The properties are stored together in a Python dictionary  called  PageProps.  The  syntax
       looks like in this example:

         PageProps = {
           1: {
                'title': "Title Page",
                'transition': PagePeel,
                'sound': "background_music.mp3"
           2: {
                'title': "Another Page",
                'timeout': 5000

       The  PageProps  definition  (and  only  the  PageProps  definition)  will  be rewritten by
       Impressive if the S key is pressed. User-defined  PageProps  entries  will  also  be  left
       untouched, except for some pretty-printing.

       The name of the presentation is shown in the title bar of the Impressive window (if not in
       fullscreen mode). By default, the file name or (if available) PDF metadata title  will  be
       used  for  this  purpose,  but  the  presentation  title  can  also  be  explicitly set by
       overwriting the DocumentTitle variable:
           DocumentTitle = "My Presentation"

       Another useful variable, AvailableTransitions, contains a list of all  transition  classes
       that  may  be  used  for  randomly  assigning  transitions to pages lacking the transition
       property. Thus, if a certain transition is undesired (either because of  personal  dislike
       or  because  it  shall  be  used  exclusively on pages where it is manually assigned using
       PageProps), something like the following can be written:
       On the other side, it's possible to activate transitions that are not enabled by default:
           AvailableTransitions += [SlideUp, SlideDown]
       Alternatively, AvailableTransitions  can  be  completely  overwritten  to  have  the  same
       transition (or set of transitions) assigned to all pages:
           AvailableTransitions = [Crossfade]

       Another  use  of  info  scripts  is  overriding  the default or command-line settings on a
       per-file basis. This can be done by simply overwriting  one  of  the  variables  that  are
       defined at the beginning of Each of these variables corresponds either to a
       command-line setting, or to some constant related to visual appearance or performance. So,
       for example, to force fullscreen mode for a presentation, write
           Fullscreen = True

       The  working directory while executing the info scripts themselves is always the directory
       in which the info script is stored in.

       The base directory for external  actions  that  originate  from  Page  Properties  or  PDF
       hyperlinks is always the directory of the PDF or image file this page belongs to. In other
       words, if e.g. 'sound': "music.mp3" is  written  in  the  info  script  for  one  page  of
       presentation.pdf,  the  file  music.mp3 is expected to be located in the same directory as


       Impressive  and  its  documentation  has  been  written  mainly  by  Martin   J.   Fiedler
       <>,   with   small   portions   of  the  code  written  by  external
       contributors. See the source code file for details.


       Report bugs to to <>.