USAGE: videoviewer <source> [-<key> <value> .. ..]
  interactive (mpeg)viewer.
SOURCE:
  0..9                       Cameranumber, if supported.
  <videofile>                Decode, if supported.
  [<path>/][<name>]%[0]<width>d.<imagefile_extension>
                             The first file can have number 0 or 1.
  <imagefile>                Files with extensions recognized by OpenCV.
  <directory>/               All <imagefile>s in <directory>. I.e.:
                 *.BMP *.bmp *.JPEG *.jpeg *.JPG *.jpg *.PBM *.pbm *.PGM *.png
                 *.PNG *.pgm *.PPM *.ppm *.TIF *.tif *.TIFF *.tiff
Max. width of <imagefile>s is 20480 (cf libswscale/swscale_internal.h).
KEY         VALUE                  EFFECT AND DEFAULTS
-+         <skip>                  do not show first <skip> pictures.
-+         <minutes>.<fraction>    do not show first <skip> pictures.
                                   1500 pictures/minute is assumed.
-@         <filename>              open directory at <filename>.
                                   Default: First file in alphabetical order.
-.         <string>                fixedmessage. Default "".
-a[ccerate] <acceleration>         grab frames of movie without displaing them.
                                   Default: 1 (disabled).
-A[namorf] <yscalefactor>          4:3 --> 16:9 resized image.
-b[uffer]  <buffersize (3..999)>   Default: 50 for images, 400 for video .
                                   buffersize may be reduced automatically to
                                   allocate not more than 1000000000 pixels.
                                   N.B. based on the size of the first image.
-c[olours] <windowsize>            Default: 160 .
-c[olours] 0                       do not show Pixel colours.
-d[est]    [#]<prefix>             Default: "videoviewer".
                                   with # use serialnumber, not picturenumber.
-d[est]    [#]-                    Replace <prefix> by basename of loaded
                                   image, videofile or "Camera<nr>".
-e[nlarge] <zoom>/<range>/<interpolation> Default 50/200/1 .
                                   <zoom> and <range> are factor *10.
                                   <interpolation> in [0,4]:
                                   0 CV_INTER_NN
                                   1 CV_INTER_LINEAR
                                   2 CV_INTER_CUBIC
                                   3 CV_INTER_AREA
                                   4 exact pixels.
-f[iletype] <suffix>               Default: "jpg".
                                   "-f[iletype]" changes filetypes
                                   both for saved images and matrix-subimages.
-F[ixed]   <width>/<height>        ignore scaling. If <width> or <height>
                                   is zero, the aspect ratio is conserved.
-k[ill]   <picturenumber>          implies skipping over non-existing pictures.
-k[ill]   0                        start playing continuously.
-m[atrix] <xraster>[/<yraster>]    linedistances for rasteroverlay or zero.
-o[ut]    e[rrorstream]            write progress to stderr, errors to stderr.
-o[ut]    h[elp]                   write progress to stdout, errors to stderr,
                                   write Help-info at startup to stdout.
-o[ut]    m[ute]                   do not write progress or errors.
-o[ut]    n[o]                     write progress to stdout, errors to stderr.
                                      Default: -silent no.
-o[ut]    o[utputstream]           write progress to stdout, errors to stdout.
-o[ut]    s[ilent]                 write only errors to stderr.
-o[ut]    t[alk]                   write only errors to stdout.
-r[ate]    <framerate>             for showing time only. Default:  25.00 .
-R[aise]   <WINDOW>                raise one or more windows on mouseclick.
-s[cale]   <xscalefactor>[/<yscalefactor>] show resized image. Default: 1.00/1.00 .
                                   Maximum: 10.0/10.0
-s[cale]   -<scalefactor>          show resized image rotated CCW, if h>w.
                                   Buttontext is orange for rotated images.
-S[croll]  <minimalmove>           scroll image by mousedrag. Default: 2
-S[croll]  0                       disable scrolling of image.
-T[rack]   <width>                 trackbars in a separate window.
-T[rack]   0                       trackbars above pictures.
                                   Default: 0.
-T[rack]   -1                      do not show trackbars.
-t[ext]    <filename>              append info on clicked pixels to <filename>.
                                   Format: "<filename> <info>".
-u         <filename>              append info on clicked pixels to <filename>.
                                   Format: "<info> <filename>".
-w[ait]    <delay>                 wait for key in mS. Default: 20
-w[ait]    0                       non-interactive mode.
-z[oom]    <windowwidth>[/<windowheight>] Default: 250/<windowwidth> .
-z[oom]    0                       do not show scaled picture.
-<n>[matrix] <basename>            save <n>x<n> subpictures as
                                   "<basename><1..n><1..n>.tif".
                                   as soon as opposite corners are clicked
                                   and terminate videoviewer.
WHERE <WINDOW> is:
   a or A  all below.
   c or C  Pixel colours.
   s or S  Sliders (if not in main window).
   t or T  Text (control window).
   z or Z  Sliders.


PROTOCOL:
 Click Left mousebutton in picture:        write RGB valuesand distance to
                                           previous point to stdout.
                                           With -z a scaled image is produced.
                                      With -z 0 -c 0 only coords are written. Drag Left mousebutton in picture:         scroll image if enabled with -S.
 Click Right mousebutton in picture:       pause/get next 0 images.
 Click Right mousebutton holding Ctrl:     show next image in video.
 Draw or click slider:                     pause and show stored image.
 Press TAB:                                Enter memnonic text.
                                 The image is displayed in inverted colours.
                                 Press Esc to cycle overlaycolour.
 Press .:                                  write fixedmessage to text.
 Press :                                   edit <filename> with vi.
 Press spacebar:                           pause/resume.
 Press a:                                  enable/disable acceleration.
 Press A:                                  increase acceleration.
 Press C                                   to cycle overlaycolour.
 Press D:                                  decrease acceleration.
 Press b,<:                                pause and show previous stored image.
 Press 1,2,3,4,5:                          same as 25,16,10,5,2x b.
 Press +,-:                                next, previous reference colour.
 Press c:                                  show default reference colour.
 Press d before left mousebutton click:    write RGBY values of horizontal
                                           and vertical line to stdout.
 Press m:                                  undo mouse click (no save matrix).
 Press n,>:                                 pause and show next stored image.
 Press 6,7,8,9,0:                          same as 2,5,10,16,25x n.
 Press f:                                  show next second of images.
 Press g:                                  get next 0 images.
 Press j:                                  show [not] every picture.
 Press p:                                  play continuously.
 Press r:                                  restart video.
 Press s:                                  save
                       save picture as "<prefix><picturenumber>.<suffix>"
        or its <n>x<n> subpictures as "<basename><1..n><1..n>.tif".
 Press u:                                  reset scrolling offset.
 Press v:                                  show next image in video.
 Press x,y,z:                              create/destroy copy of image.
 Click Left mousebutton in colours:        show next reference colour.
 Click Right mousebutton in colours:       show previous reference colour.
 Press q:                                  terminate application.
 Press h or ?:                             write help to stderr.
 Press !:                                  write reference colours to stderr.
 Finally you can use the buttons:
Restart  [Prev  Next]  Get  Get000  Play  Pause  Exit  Help
 Using buttons while pressing Ctrl will just write the x-coords to stdout.
 "m" is required if saving subpictures is combined with scrolling.
RETURN VALUES: 0 Ok, 1 Too few args, 2 syntax-, 3 file-, 4 runtime-error.
USING: OpenCV version 1.1.0 (1.1.0)
VERSION: Jun 24 2014

Copyright (C) 2011 by Harm J. Schoonhoven

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