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       monitest - Monitor test program


       monitest [modestring]


       monitest  is  intended to test ggi drivers (during development) and the
       optical quality of monitors (later). Don’t be too disappointed  if  you
       find a weakness in your monitor, mine is probably worse than yours.

       The  main feature is a test screen like broadcast in former days before
       24 hour TV programs. It is used to test geometry and resolution of  the

       Also  included are several test screens for testing moiree effects, the
       horizontal and vertical screen resolution, and colour convergence.

       You will be  able  to  switch  resolution  on  the  fly,  to  find  out
       interactively  what modes the driver supports and how much of this your
       card/monitor can do with acceptable quality.


              Specify the mode to use


       The basic grid is white on black and has sixteen times  twelve  fields.
       On  a  tube with 4:3 ratio each one should be square, even if the pixel
       size of the screen does not have 4:3 ratio. The  lines  are  one  pixel
       wide.  They  should  be  straight,  even  in  the corners, and not have
       coloured borders.

       There is a big circle in the middle and smaller circles in each corner.
       They  are round pixelwise, so they should be circles if the screen size
       ratio (width:height of visible area) is equal to the  pixel  ratio.  It
       usually  should  be  4:3.  So  the  best sizes for testing are 320x240,
       640x480, 800x600 and up.

       In each corner there is one box with vertical stripes.  These  are  one
       pixel  wide,  with  one  pixel  distance,  so  you  get  maximum signal
       frequency and can see how well your monitor and video card  handle  the

       The middle field has eight solid blocks with the eight colours, i.e all
       combinations of the red, green and blue  signals  turned  on  and  off.
       Below it there are four fields with vertical stripes as in the corners,
       but in white and the three basic colours red, green and blue. Below  it
       there  is  a  bar  with  these  four colours red, blue, green and white
       blending from full intensity (left) to  zero  intensity  (right),  i.e.

       In  the  middle the current resolution is printed. Maybe horizontal and
       vertical frequency will be printed too, if I can get  the  information,
       which is not (yet) implemented in the LibGGI API.

       Convergence means how well the red, green and blue picture are aligned.

       This is tested by painting a grid of red, green and blue + signs.  They
       should be aligned properly where they touch. Usually they don’t...

       There are four patterns like this, rotating the colours. Press space to
       switch forward, or press q to quit anytime.

       Once again there are several screens, press space to step thru them.

       Vertical white stripes with width 1, 2, 3 and 4 pixels.  See  what  the
       highest dotclock is the monitor can handle.

       Horizontal  stripes  with  width  1 and 2 pixels. See how well the scan
       lines are separated.

       Three stars of black lines on white, with a width  and  space  (at  the
       sceen  borders)  of  1 and 1, 1 and 5, 2 and 10 respectively. Watch for
       colour changes, and once again you can see the maximum  frequency  your
       monitor can do.

       Vertical bars in red, blue, green and white, with the width of 4, 3, 2,
       1, 2, 3 and 4 pixels  for  bar  and  space.  See  whether  there  is  a
       difference in resolution between the colours. And watch, again, for the

       I don’t know whether these tests work, my monitor  is  rather  good  in
       this respect. Please gimme some feedback!

       If  there is interference between the monitor mask and a grid displayed
       on the monitor, a change of colours can be seen, and is sometimes  very
       annoying.  There  are  three  tests present, each one comes in the four
       colour combinations black, red, green and blue on  white  background  :
       vertical  stripes,  one  dot  wide,  with  one dot space; white dots on
       colour ground, spaced two and two (run testscreen  with  a  really  low
       resolution to see what I mean :-); a chessboard.

       This  test  allows you to drag a coloured rectangle around, looking for
       pixels that are always on or off, which is, as far as I know, the  most
       common failure of flat panels.

       The rectange is moved using the mouse or the arrow keys.

       The  color of the rectange can be changed by pressing the primary mouse
       button (usually the left one) or <Space>, cycling through (black,
       red, green, blue, white) or by pressing a number between 0 and 4 or the
       first letter of the colour (b is blue).

       Dragging with the  second  button  pressed  changes  the  size  of  the
       rectangle. Every other key terminates this test.


       ·   If  you  switch  depth, the program might crash badly. This will be
           solved once I figure out mode  checking  or  using  a  target  that
           (opposed to the X targets) supports that.


       monitest was written by Hartmut Niemann.