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       Impressive - presentation tool with eye candy


       impressive [OPTIONS...] FILES...


       Impressive is a simple presentation program that displays slideshows of
       image files (JPEG, PNG, TIFF and BMP) or PDF  documents.  Rendering  is
       done via OpenGL, which allows for some "eye candy" effects.


       -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 slideshows.

       -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 Xpdf is used for

       -b or --noback
              Disabled  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).

       -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 once.
                     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 resolution).
                     Like above, 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

       -C <filename>[:<X>,<Y>] or --cursor <filename>[:<X>,<Y>]
              This option can be used to specify the path  to  an  image  file
              (typically  a  transparent .png) that shall be used as the mouse
              cursor instead of the default one. Optionally, the  hotspot  may
              be specified (this is the position inside the cursor image where
              the  real  mouse  position  is   located).   Example:   --cursor

       -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. Default value: 3000 ms.

       -e or --noext
              OpenGL  normally  only  supports  textures   with   power-of-two
              dimensions.  This  means  that for a 1024x768 screen, the actual
              texture size will be 1024x1024, for 1600x1200 it  will  even  be
              2048x2048.  To  overcome  this  limit  and  save texture memory,
              Impressive  will  automatically  use   the   OpenGL   extensions
              GL_ARB_texture_rectangle  (available  on most graphics cards) or
              GL_ARB_texture_non_power_of_two (available  on  modern  graphics
              cards  with current drivers). If these cause any trouble, the -e
              option  may  be  used  to  prevent  Impressive  from  using  the
              problematic extensions.

       -f or --fullscreen
              Toggles   fullscreen   mode.  By  default,  fullscreen  mode  is
              activated, and can be deactivated using this switch.

       -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 default.

       -g <width>x<height> or --geometry <width>x<height>
              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.  Note that this
              option  is  not  the  standard  X  "geometry"  option  and  does
              therefore  not  support  window positioning (e.g. -g 800x600+0-0
              will not work!).

       -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

       -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.

       -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>
              Specified the OSD layout. Read below for an explanation of  this

       -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.

              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

       -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  you’re  going  to  give a
              presentation on a foreigh PC with an old,  broken  or  otherwise
              problematic  Xpdf  or  GhostScript  installation:  By generating
              images of the PDF pages you can ensure 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
                     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 page.
              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

       -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.

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

       -R <X>x<Y> or --meshres <X>x<Y>
              Most effects  subdivide  the  visible  screen  into  a  mesh  of
              rectangular  or  quadratic pieces, each with its own coordinates
              and alpha blend values. Using this parameter, the resolution  of
              the subdivision mesh can be defined. The default value is 48x36.
              On slow machines, lower values like 24x18 or  12x9  can  heavily
              speed  up transition rendering at the cost of visual quality. On
              the other hand,  higher  values  like  64x48  or  96x72  improve
              quality, but use much more CPU cycles.

       -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.

       -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 transitions.

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

       -u <seconds> or --poll <seconds>
              If this option is specified, the source file or  directory  will
              be  checked  for changed 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 disappeared.

       -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

       -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 presentations.

       -z <factor> or --zoom <factor>
              Sets  the  zoom  factor that is used in zoom mode. It must be an
              integer value of at least 2. The default value is 2.  Note  that
              it  might  not be possible to get high-quality zooming for large
              zoom factors due to hardware restrictions.

       -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, JPEG, PNG, TIFF, BMP and PGM/PPM. 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.


       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


       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  (except  for Q and Esc) or mouse click 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.


       Q key or Esc key
              Quit Impressive immediately.

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

       RMB (right mouse button), 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.

       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 or MMB (middle mouse button)
              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.

       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 and blurry rendition. Only the highlight  boxes  will  be
              displayed in their original lightness and sharpness.
              If  a page with highlight boxes is left, the boxes will be saved
              and restored the next time this page is shown again.

       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. 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

       R key
              Reset the presentation timer.

       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 / - key or mouse wheel
              Adjust the spotlight radius.

       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 key / W 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 mode.

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

       Cursor keys in overview mode
              Navigate through pages.

       Alt+Tab keys
              Leaves  fullscreen  mode  to  facilitate  task  switching  while
              running full-screen presentations.

       Any other alphanumeric (A-z, 0-9) or function key (F1-F12) 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 permanently stored  with
       the S key.


       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  between  this page and the following
              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 between this page and the following
              page shall be shown.

              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

              This boolean property can be set to 1/True if the page shall  be
              skipped during the presentation.
              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
              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 pressed.

              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 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. Note that this function is highly
              experimental and might not work reliably on every system!

              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 programs.
              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.

       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 you want to  exclude
       a  certain  transition (either because you don’t like it or because you
       want to have it exclusively on pages where  you  manually  assigned  it
       using PageProps), you can write something like
       On  the  other side, it’s possible to activate transitions that are not
       enabled by default:
           AvailableTransitions += [SlideUp, SlideDown]
       Alternatively, you can  completely  overwrite  AvailableTransitions  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


       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 <>.