Kraków, 5-05-1998Video Stereo Digitizer
The AGH Video Stereo Digitizer (VSD) it is a stereoplotter adopted for production of vectorial maps with the use of the pairs of digital black and white or color photogrammetric images (stereopairs or orthostereopairs). The VSD can accept CDD images or scanner images or scanned satellite, aerial or terrestrial photograms.
The VSD plotter can be used for evaluation of topographic maps, and can also serve very well or recording of plants of historic moments of architecture or arts as well as the archaeological plans mapping. Plotted details of the pair of digital images displayed on the PC - SVGA screen are selected by the human operator with the use two cursors animated by a mouse. Selected points can be connected by the polygon line. Irregular curves are plotted (digitized) by recording of cursor trajectory. The polygons and trajectories are superimposed over the half tone images on the PC screen in a chosen color. To each color of displayed numerical map an individual layer is assigned in the computer memory (data base) in the DXF-code or binary code.
The AGH Video Stereo Digitizer can be used also as mono or stereo comparator for the measurement of the digital images with the accuracy of the screen pixel fraction; the accuracy depends on the digital image zooming coefficient.
2. Digital images
Program accepts the following formats for digital images:
1. TIFF monochromatic non-compressed (max. 256 half tone steps)
2. Indexed Color TIFF with the palette 256 colors.
Only 248 positions in the palette will be used for digital image however, because remaining 8 colors is reserved for numerical map displaying on the screen.
3. The monochromatic pixel map format:
Monochromatic format organized as a simple stream of pixels (max. 256 half tone steps). For this format the length of line and image offset must be defined.
Before starting VSD program few directories devoted to the VSD program have to be created. Digital photographs can be stored in one or more directories. File ProjectName.PKT (described below) must be placed in the pre prepared directory which will be declared by name at the program initiation as the one accompanying restitution and plotting.
Existing vectorial maps in DXF format can be included to the project by transformation DXF format to the ABS format (specific VSD format). For such transformation special program DXF_ABS.EXE is provided.
Directory accompanying restitution and plotting contain also files produced by VSD program:
ProjectName.ETK - histogram and other information's about photographs
ProjectName.CFG - parameter of the project, it is: stereopaire or a single photo
ProjectName.S?? - reduced size pair of photos or single photo to select the working frames
ProjectName.LU - files containing coordinates of surveyed points- binary file
ProjectName.LU1 - as ProjectName.LU, but for the single photograph - binary file
ProjectName.OR - as ProjectName.LU1 or .ProjectName.LU, but ASCII file
_OR_REL.WYN - temporary files containing results of
_OR_ABS.WYN - subsequent steps of stereopair orientation
ProjectName.PKT - preprepared ASCII data:
- No. and coordinates of fiducials and/or reseau grid
- No. and field coordinates of control points
ProjectName.ADP - parameters of distortion (by method of ORIENT)
Name.MAP - ASCII file of map lines in the image coordinates (an internal format)
Name.ABS - Binary file map lines in the field coordinates (an internal data format)
Name.DXF - file Name.ABS in the DXF format
Name.PNT - ASCII file of 3D or 2D points in the field coordinates ( no. x y [z] )
Attention. The last 3 files can be of the project name, but can bear any other name to enable several plotting files from the same pair of pictures.
4. Starting of the program
Program can be started by keying VSD L or VSD H . VSD L calls for screen resolution 800x600, VSD H calls for screen resolution 1024 x 748 pixels, and VSD S - for 1280 x 1024 pixels.
If you want to omit the title screen you must press key "escape" just after starting.
At the beginning program will ask about:
- path to project directory
- project name
- names of digital-photo files or names with paths to the photo files, but particularly in case when the photo-files are located in other directories then default for project
- selection of a image portions on the supporting reduced-resolution pictures.
A green rectangle can be shifted by the operator simultaneously both pictures or independently on left or right pictures, switched by TAB.
To create 1:1 resolution picture on the screen the left mouse button or ENTER key must be used.
5. Orientation and plotting
- Interior orientation:
- survey of 2 or more fiducial marks [I]. To use for calculation the coordinates from
file ProjectName.PKT with the calibration results use Point Number and [INS]
- calculation of transformation parameters [F5] (calculation can by performed here, or
after all the survey for relative and/or absolute orientation is completed)
- Relative orientation
- survey of 5 or more points selected by key [H]
Here you can use supporting semi-automatic correlation [F9]
- calculation of relative orientation elements [F6] (with entering elements of interior orientation and coefficients radial/tangential distortion )
- Absolute orientation
- survey of 3 or more pass-points (all points must have xyz coordinates)
To use coordinates from the file ProjectName.PKT insert Point Number and press [INS]
- calculation of absolute orientation elements [F7]
All the above operations were performed in the stereocomparator mode (with the use [TAB] and ).
To erase surveyed point use the number of point with minus.
To erase group of surveyed points use the number zero.
- Stereoplotter mode
- to activate the stereoplotter mode use [F8] (calculation of DLT coefficients)
- or read DLT coefficients from the file ProjectName.DLT [Alt F8]
For plotting use the polygon line [P]...[P]...[K] or trajectory [T]...[K]. You can correct mistakes [U] or [TU]. During plotting you can visualize existing vectorial map [E], and you can plot simultaneously 7 layers (colors [B]) to update the existing vectorial map or to produce your own file.
There exist 3 plotting supporting routines:
- semiautomatic correlation [F9]
- automatic tying vector end to existing points of polygon (few pixels correction) [D]
- automatic designing of line orthogonal to existing vector [N], [Alt N]
6. Program installation
Basically it would be enough to create a special directory under name VSD, and to copy to that directory all the files from the installation diskette.
It would be advantageous, however, to add to the set of system paths in the AUTOEXEC.BAT file also the path to the VSD directory:
PATH = . . . . . . . . . . . . . . .. ; C:\VSD
Instead of the above you can copy VSD.BAT file to one of the directories already existing in the AUTOEXEC.BAT path.
Extended RAM memory is employed by the VSD - system, and therefore it must use (independly installed) HIMEM.SYS driver and has to have adequate RAM memory available (1408 Kb for resolution 800*600, 2048 for resolution 1024*768, and 3328 Kb for resolution 1280*1024 pixels on the screen). To do that, you should add to the CONFIG.SYS file at least:
DEVICE = C:\DOS\HIMEM.SYS /NUMHANDLES=128
FILES = 40
In case of lack of adequate extended memory one can try to use an /d calling parameter.
VSD uses a 3-button mouse, and therefore also the mouse driver must be installed before VSD program initiation.
VSD - program works in the VESA standard and requires the adequate graphic VESA standard card or additional program that emulates the VESA standard.
We wish you good luck with the installation.
7. Menu and active keys
The system can be controlled directly by active-keys or via multi-level menu.
Hot Abbr. Meaning
Image Selection of the image portion and the scale of ____ visualization
V select selection of another image portion for visualization
- submenu: [E] - visualization of recorded vectorial map
[*] - visualization of recorded points
[Tab],  - similarly for cursor moving
C center cursor together with image shifting to the screen centers
Z zoom image enlarging two times
M zoom image reducing two times
Alt Z zoom selection of coefficient for zooming (negative - reducing)
Ctrl Z magnifier measuring magnifier
R refresh refresh screen and redraw vectorial map
Alt R restart back to the photo 1:1 scale
Ctrl R hide hide the raster background
0(zero) go_to image centering to the point indicated by coordinates entered from
keyboard or by number and key INS from *.PKT file
F filter edge sharpening on the full screen
Y Y-parall image y-parallax clearing at the stereocomparator mode
O look a look on the photo at 1:1 scale
Map Visualization of the vectorial map on the raster image___
E import import or erase vectorial map (erasing for name = SPACE )
Alt U erase erase of current vector map
Ctrl E map_2D import 2D vectorial map and set Z coordinate of all vectors to average elevation of control points
Ctrl D elevation change elevation of 2D vectorial map to current elevation of cursor
Alt E hide hide / show vectorial map
Alt B list viewing the list of layers with attributes
Ctrl B layer selection the layer by indicated vector
Alt J points_J import points of J-group from ASCII file *.PNT
F12 save save vectorial map to *.MAP file
plotting Plotting of the vectors of the map____________________
P polygon coordinates recording for the first or next points of polygon
B layers selection or adding or modification of the thematic layers
K end coordinates recording for the last point of polygon
D tie-up tie the line to the existing indicated point J or end of vector (snapping)
.(point) connect designing of a line connected to a point indicated on the vector
(crossing of 2 vectors)
N ortho designing of a line orthogonal to the vector
Alt N ortho designing of a (leveled) line orthogonal to the vector
T trajectory initiation of recording of cursor trajectory
Alt T step entering a step of recording of cursor trajectory
U erase erasing a pointed vector of polygon
Bcksp erase erasing the last recorded vector
TU erase erasing the end part of trajectory
J point recording of point
cursor Selection of the cursor and control of cursor________
X shape cursor shape selection
L coLor cursor color selection
SPACE point cursor shape reduced to the pixel-size
F1 lower lowering of the cursor along plumb line
F2 upper raising up the cursor along plumb linereference Image orientation and the reference coord. systems def._
I record_I fiducial marks recording (INS - enter coordinates from *.PKT file)
H record_H recording points for relative orientation
G record_G recording points for absolute orientation (INS - coord. from *.PKT)
F5 fiducials determination of transformation to the fiducials or transformation to reference coord.system for mode of mono-image
F6 relatori calculation of relative orientation elements
F7 absori calculation of absolute orientation elements
F8 dlt activation of DLT
F9 autocorrel semi-automatic stereo-correlation
F4 dlt calculation of DLT for non-metrics photos
F3 net linear net adjustment for single image
' coord change of the coordinate system definition for single image
Alt F7 absori calculation of selected elements of multistage absolute orientation
Alt G passfile reading new list of field points from *.PKT file
Alt F8 DLT reading DLT coefficients from *.DLT file
control Switching of mode of the cursor control________
- reduce reduce the cursor speed
+ increase increase the cursor speed
Alt gray+ step entering a step of cursor moving
TAB cntrl_1 blocking of left/right cursor
1 cntrl_2 simultaneous control of the pare of cursors
A stcmp on / off fast changing of elevation
Alt A mode switch of mode of fast changing of elevation
S control floating mark controls modes
F (blue) - photogrammetric (field) coord.syst.
G (yellow) - object (field) coord.syst. (in which all pass points where defined)
M (magenta) - 3D fiducial coord.syst. - left camera
I (white) - above for nonmetric images
screen Changing status of the screen_______________________
W display coordinates display switch
white - 2D image coord.syst. (in pixels)
cyan - 2D fiducial coord.syst. (in mm)
magenta - 3D fiducial coord.syst. -left camera
yellow - 3D object (field) coord.syst.
blue - 3D photogrammetric (field) coord.syst.
* mark visualization of recorded points on the screen (on/off )
Alt 8 (*) numbers visualization of point numbers
Alt F2 slide screen registration in file *.TIF, *.BMP or *.PCX
Alt F1 ram rapport of computer RAM and status VSD
others Miscellaneous_______ ___________ ___ ___
\ length calculation of pointed vector length
= area calculation of pointed polygon area
menu Calling of the VSD function__________________________
Escape call for the menu /erase menu, call multilevel text menu
INS menu shift menu to the screen top/bottom
F10 menu show graphics menu operational for plotting (experimental)
Alt Q DOS temporary exit to DOS
Q Q-system saving files of vectorial maps followed by quitting the VSD system