OMA for Mac OS X
User’s Guide
Version 2.0b – December 2003
OMA for Mac OS X User’s Guide
2
OMA for Mac OS X User’s Guide
3
The Command Window
This window is used for the command driven functions of the OMA program and behaves much
like a standard terminal. The Command Window can be resized, and moved but not closed. Text scrolled
off the top of the window is not lost and can be viewed by the "page up", "page down", or arrow keys.
A blinking cursor is displayed when the Command Window is selected. The standard prompt for
new commands is "OMA>". Commands entered from the keyboard are terminated with "return" or "enter".
Only the first part of a command name needs to be entered. If this leads to ambiguity the parser will take
the first suitable command (in alphanumeric order) that appears in the internal command buffer, so
caution should be exercised when abbreviating commands.
Copying and pasting text in the command window works as in other Macintosh applications. This
may be useful for keeping a record of a data taking session. It may also be useful to copy filenames or
parts of filenames so that they can be pasted with "cmd V" or the "Paste" menu item.
The Status Window
The status window is for the display of data associated with the image and its display. The
Command Window cannot be closed or resized, only minimized.
OMA for Mac OS X User’s Guide
4
The top most pane contains information about the limit values for the false color palette. The pixel
intensity that corresponds to the first value in the colour-map is displayed in the “Color Min:” register.
The pixel intensity corresponding to the last value in the color-map is displayed in the “Color Max:”
register. These values can be specified by the CMINMX [n][m] command, or by using the buttons to
increase or decrease the values. The value is incremented by a set amount. Sliding the “Min/Max
Increment” control changes the increment. If the “Update” set box is checked, the current displayed
image (if there is one) will be updated and redisplayed to the new color parameters. If the “Scale” check
box is checked, then the color map will scale to the minimum and maximum intensities in the image,
equivalent to using CMINMX without arguments.
The second pane specifies the bounds of the current rectangle, if the rectangle tool is selected. If
the cursor tool is selected clicking in the image will display the pixel location and intensity here.
Information about the Image Dimensions, Location on a CCD (X0, Y0 - seldom applicable) or information
about pixel binning (DX, DY). Cursor tools are selected using the icons in this pane.
Finally, there is a line indicating the current macro number as it executes and a strip indicating the
current palette color-map.
OMA for Mac OS X User’s Guide
5
Menu Commands
All commands beginning with the letter k have menu selection items associated with them. (The
second letter of the command is the command- key code associated with the menu item.)
Thus, these commands can be invoked three ways:
(1) By menu selection,
(2) by the associated command-key code, or
(3) typing the "k" command, which is echoed in the command window.
The reason for including this option is so that these functions can be performed from within a macro.
File Prefixes and Suffixes
To specify the path and file type (or extension) for files typed in the command window, prefixes
and suffixes may be specified using the Prefixes tab in the OMA Preferences <cmd f>:
OMA for Mac OS X User’s Guide
6
Different paths and suffixes can be used for “getting” and “saving” data files, for macro files, or for
Settings Files saved with the “SAVS” or retrieved with “GETS.” OMA now uses the Mac unix style paths.
In the example above, data files would be saved and retrieved from a folder named “recent” contained
within a folder “image data” on the boot disk (regardless of the name of the boot disk on the desktop).
Macros would be saved and retrieved from a folder named “macros” on a different disk (or partition) that
would appear on the desktop as “extra drive.”
OMA for Mac OS X User’s Guide
7
Constant Arithmetic Commands
+n
– Constant Addition
Arguments
n - INTEGER constant integer value to be added onto each pixel.
Description
Adds integer value n to every pixel in the current image in the data buffer.
The plus sign and the integer argument that follows it must be separated by a space.
Example
+ 255 will add 255 counts onto every pixel in the image buffer.
See Also
-, *, /, ADDFIL
-n
– Constant Subtraction
Arguments
n - INTEGER constant integer value to be subtracted from each pixel.
Description
Subtracts integer value n from every pixel in the current image in the data buffer.
The negative sign and the integer argument that follows it must be separated by a space.
Example
- 255 will subtract 255 counts from every pixel in the image buffer.
See Also
+, *, /, SUBFIL
*x
– Constant Multiplication
Arguments
x - FLOAT constant float value to be multiplied to each pixel.
Description
Multiplies each pixel in the current image buffer by the value of x. The value can be either an
integer (cast to a float) or a float value. Pixel values are rounded off to the nearest whole
integer when applied to the new image buffer. The multiplication sign and the real argument
that follows it must be separated by a space.
Example
* 3.07 will multiply each pixel in the buffer by 3.07 and round the result off to the nearest whole
integer. This may affect the scale factor if the value overruns the largest natural integer value
available
See Also
+, -, /, MULFIL
OMA for Mac OS X User’s Guide
/x
8
– Constant Division
Arguments
x - FLOAT constant float value by which each pixel is to be divided.
Description
Divides each pixel in the current image buffer by the value of x. The value can be either an
integer (cast to a float) or a float value. Pixel values are rounded off to the nearest whole
integer when applied to the new image buffer. The slash sign and the real argument that
follows it must be separated by a space.
Example
/ 5.5 will divide each pixel in the buffer by 5.5 and round the result off to the nearest whole
integer. This will affect the scale factor if it is not equal to 1.
See Also
+, -, *, DIVFIL
FLOAT variable_name
– Define a Float Variable
Arguments
variable_name - Specifies a variable used to hold a float value
Description
The variable name should not be the same as an existing OMA command. The value stored in
variable_name can be used as a float in other commands by specifying @variable_name.
Example
FLOAT pkangle
pkangle = %b / 23.2
* @pkangle
See Also
INTV, VARIAB
INTV variable_name
– Define an Integer Variable
Arguments
variable_name - Specifies a variable used to hold an integer value
Description
The variable name should not be the same as an existing OMA command. The value stored in
variable_name can be used as an integer in other commands by specifying @variable_name.
Example
INTV pkcount
pkcount = %d * 3
+ @ pkcount
See Also
FLOAT, VARIAB
VARIAB
– List Defined Variables
OMA for Mac OS X User’s Guide
9
Arguments
none
Description
Lists currently defined variables and their values. Variables are defined using simple arithmetic
expressions, such as
my_var = 10
y = my_var*2
Example
The values of variables are accessed from other commands using @my_var.
+ @my_var
save datfile_@4myvar
In loops, the end of a variable can be tagged by adding ‘\'.
save datfile_@my_var\_corrected
See Also
FLOAT, INTV
OMA for Mac OS X User’s Guide
10
File Arithmetic Commands
ADDFIL filename
– Add a file to the OMA image buffer
Arguments
filename - Specifies the name of an existing OMA file.
Description
Adds the contents of an OMA file of a given name to the data in the current image data buffer.
The file specified must exist and it must have the same dimensions as the current image in the
buffer, otherwise OMA will give an error. The filename uses the file prefixes as set by UPREFX.
Example
GET datafile
* 2.1417
SAVFIL temp
ADDFIL datafile
See Also
DIVFIL, MULFIL, SUBFIL, PREFIX, UPREFX
DIVFIL filename
– Divide the OMA image buffer by a specified file
Arguments
filename - Specifies the name of an existing OMA file.
Description
Divides the contents of the OMA buffer by the specified OMA file. The file specified must exist
and it must have the same dimensions as the current image in the buffer, otherwise OMA will
give an error. The filename uses the file prefixes as set by UPREFX.
Example
GET datafile
* 2.1417
SAVFIL temp
ADDFIL datafile
See Also
ADDFIL, MULFIL, SUBFIL, PREFIX, UPREFX
OMA for Mac OS X User’s Guide
MULFIL filename
11
– Multiply the OMA image buffer by a specified file
Arguments
filename - Specifies the name of an existing OMA file.
Description
Multiply the contents of the OMA buffer by the specified OMA file. The file specified must exist
and it must have the same dimensions as the current image in the buffer, otherwise OMA will
give an error. The filename uses the file prefixes as set by UPREFX.
Example
GET datafile
* 2.1417
SAVFIL temp
ADDFIL datafile
See Also
ADDFIL, DIVFIL, SUBFIL, PREFIX, UPREFX
SUBFIL filename
– Subtract a file from the OMA image buffer
Arguments
filename - Specifies the name of an existing OMA file.
Description
Subtracts the contents of an OMA file of a given name from the data in the current image data
buffer. The file specified must exist and it must have the same dimensions as the current
image in the buffer, otherwise OMA will give an error. The filename uses the file prefixes as set
by UPREFX.
Example
GET datafile
* 2.1417
SAVFIL temp
ADDFIL datafile
See Also
ADDFIL, DIVFIL, MULFIL, PREFIX, UPREFX
OMA for Mac OS X User’s Guide
12
Accumulator Buffer Commands
ACADD
– Add the OMA Image Buffer to the Accumulator
Arguments
none
Description
Adds the current image data buffer to the accumulator buffer.
See Also
ACCUMU, ACGET, ACDELE, ACPDF
ACCUMU
– Allocate a 32-bit Accumulator Buffer
Arguments
none
Description
Allocates and clears memory for a 32-bit image accumulator buffer that can be used to sum
individual images. The size of the accumulator is determined by the scan parameters when
the accumulate command is first given.
Example
ACCUMU
LOOP n 1 10
GET %s@n
ACAD
LOOPND
ACGET
/ 10
See Also
ACADD, ACGET, ACDELE, ACPDF
ACDELE
– Delete the Accumulator and Free Memory
Arguments
none
Description
Adds the current image data buffer to the accumulator buffer.
See Also
ACCUMU, ACADD, ACGET, ACPDF
OMA for Mac OS X User’s Guide
ACGET
13
– Move the Accumulator to the OMA Image Buffer
Arguments
none
Description
Moves the data from the accumulator buffer into the current image data area. The previous
contents of the image data buffer are destroyed.
See Also
ACCUMU, ACADD, ACDELE, ACPDF
ACPDF n
– Accumulate a PDF of 2 Variables
Arguments
n - the single channel of the data to be used in accumulating the pdf
Description
Accumulate a pdf of 2 variables. The binning parameters are selected with the SETUP
command.
See Also
ACCUMU, ACADD, ACGET, ACDELE, SETUP
OMA for Mac OS X User’s Guide
14
Image Processing Commands
ABSOL
– Absolute Value of OMA Image
Arguments
none
Description
Take the absolute value of the data in the current OMA Image buffer.
BLKAVE avg_flag
– Set the behaviour of BLOCK command
Arguments
avg_flag - BOOLEAN Width of the new image (default = 1)
Description
Set a flag that determines whether or not the BLOCK command sums or averages the values
within the specified block. If avg_flag=0, sum the values otherwise average.
See Also
BLOCK
BLOCK n m
– Group the OMA Image Data
Arguments
n - INTEGER Horizontal Width of the Data Bin
m - INTEGER Vertical Height of the Data Bin
Description
Group data into n x m blocks. This command reduces the size of the
data buffer. The values are averaged.
Example
BLKAVE 0
BLOCK 2 2 ;reduce size of image by half. Adjacent pixels added together
See Also
BLKAVE
OMA for Mac OS X User’s Guide
CALC
15
– Calculate Statistics from Selected Region
Arguments
none
Description
Print calculations on the region of the current image as specific by RECTAN command or
defined with the mouse. Currently the average, rms, # of points, and the x and y "center of
mass" are printed..
See Also
CALCAL, RECTAN
CALCAL
– Calculate Statistics from Entire Image
Arguments
none
Description
Print calculations on the entire image. Currently the average, rms, # of points, and the x and y
"center of mass" are printed..
See Also
CALC
CLIP [n]
– Clip Values above a Threshold
[n] - INTEGER Threshold value to clip above (default = 0)
Description
Sets all data values in the current image buffer that are > n to n.
See Also
CLIPFR
CLIPFR fraction
– Clip Values above a Threshold
fraction - FLOAT Percentage of the maximum value to clip above
Description
Clip data at a fraction of the maximum value. The fraction threshold is calculated as the value
fraction*maximum. This may cause problems if large parts of the image are negative. The
value of fraction should be between 0 and 1.
See Also
CLIP
OMA for Mac OS X User’s Guide
CORECT n
16
– Perform Background and Response Correction
Arguments
[n] - INTEGER scale factor applied to corrected image
Description
Performs corrections on the data in the current image buffer by subtracting the background
saved with the SBACK command, multiplying that result by n, and then dividing by the
response saved with the SRESP command. n is an optional argument but should be used in
most cases to avoid binning the results after they are converted to integer values.
Example
GET pkbkg
SBACK
GET pkresp
SRESP
GET %s%d
CORECT 100
See Also
SBACK, SRESP
DIFFX
– Differentiate the OMA data buffer
Arguments
none
Description
Differentiate the data in the current image data buffer in the x
direction.
See Also
DIFFY
DIFFY
– Differentiate the OMA data buffer
Arguments
none
Description
Differentiate the data in the current image data buffer in the y
direction.
See Also
DIFFX
OMA for Mac OS X User’s Guide
DIVSCA
17
– Divide Image by Scalar Average Value
Arguments
none
Description
Divide the data array by the scalar value calculated with the GETSCA command. (Yale
Command)
See Also
MULSCA, GETSCA
FILBOX
– Remove Contents of Rectangular Subregion
Arguments
none
Description
Replace the data within the sub-region (specified using the mouse or RECTAN) by
interpolating horizontally from the values on the left and right sides of the rectangular region.
Useful for removing artefacts from the region.
Example
RECTAN 23 467 38 475
FILBOX
;Define a sub-region around particle.
;remove particle
See Also
RECTAN
FLUCT [flag]
– Calculates a Fluctuating Component
Arguments
[flag] - BOOLEAN Flag to determine type of results returned.
Description
Calculates a fluctuation by subtracting the mean saved with the SMEAN command. If flag is
equal to zero, the fluctuation is calculated. This is the default behaviour. If flag is not 0, the
fluctuation^2/n is returned. No check is made for overflow.
Example
GET pkbkg
SMEAN
FLUCT 1
See Also
SMEAN
OMA for Mac OS X User’s Guide
18
FRAME W H [Val] [X0] [Y0] – Place Frame Around Image
Arguments
W - INTEGER New Image Width (W > Original Width)
H - INTEGER New Image Height (H > Orginal Height)
[Val] - INTEGER Value of Pixels within the new framed area (Default = 0)
[X0] - INTEGER Left Side Margin for New Frame (Default Centered)
[Y0] - INTEGER Top Margin for New Frame (Default Centered)
Description
Make a new sized image by adding a frame of new pixels around the old image, without
scaling the old image. Default behaviour sets
Example
GET filename
MAX
FRAME 500 500 %l
;Get a file.
;calculate maximum and minimum values
;Make image 500x500- frame values equal old min
See Also
MAKNEW
GETMAT params – Load Dewarping Parameters from File
Arguments
params - FILE Filename of ASCII file containing dewarping parameters
Description
Load the file matching parameters contained in the text file " params ". The format of the file is
as follows:
x1_ref y1_ref x1_i1 y1_i1 x1_i2 y1_i2
x2_ref y2_ref x2_i1 y2_i1 x2_i2 y2_i2
image1_width image1_height
image2_width image2_height
Note that there is no prefix added to the file name.
See Also
MATCH
GETSCA scale_factor
– Get a Scalar Average Value
Arguments
scale_factor - FLOAT Denominator of the region average
Description
Get a scalar value by averaging over a specified region and dividing by the specified
scale_factor. The region is specified using the SETUP command -- Case 3. (Yale Command.)
See Also
MULSCA, DIVSCA
OMA for Mac OS X User’s Guide
GRAD
19
– Calculate Gradient in OMA Image (Method 1)
Arguments
none
Description
Find the magnitude of the gradient of the data in the current image buffer. Currently, the scale
factor is ignored. Use 2 pixels on either side of current pixel for gradient.
See Also
GRAD2
GRAD2
– Calculate Gradient in OMA Image (Method 2)
Arguments
none
Description
Find the magnitude of the gradient of the data in the current image buffer. Currently, the scale
factor is ignored. Use the current pixels and the adjacent pixel to determine the gradient.
See Also
GRAD
INTEG [dir_flag, sel_flag]
– Sum the Current OMA Image
Arguments
dir_flag - BOOLEAN Width of the new image (default = 0)
sel_flag - BOOLEAN Height of the new image (default = 0)
Description
Sum up the data in the horizontal (dir_flag=0) or vertical (dir_flag=1) direction. The twodimensional image becomes a single line. If sel_flag=1, the subset of the image specified by
the selection rectangle is used. Possible cases are:
direction_flag = 1
direction_flag = 0
The result is an array in x; sum in y direction
The result is an array in y; sum in x direction
selection_box = 1
selection_box = 0
A selection box specifies what region to sum
Sum all channels or tracks
Example
INTEG 0 0 ; The result is an array in y; sum in x direction
INTEG 1 0 ; The result is an array in x; sum in y direction
INTEG 0 1 ; Sum the selected rectangle in the x direction
INTEG 1 1 ; Sum the selected rectangle in the y direction
See Also
INTFIL, RECTAN
OMA for Mac OS X User’s Guide
INTFIL [dir_flag, sel_flag]
20
– Sum the Current OMA Image
Arguments
dir_flag - BOOLEAN Width of the new image (default = 0)
sel_flag - BOOLEAN Height of the new image (default = 0)
Description
The same as INTEG except that the result is an image having the same dimensions as the
original data.
See Also
INTFIL, RECTAN
INVERT
– Reverse the OMA Image Pixel Order
Arguments
none
Description
Inverts the image in the current image data buffer, causing the first point to become the last
data point. This transformation is the same as rotating the image twice
Example
GET filename
INVERT
ROTATE
ROTATE
See Also
ROTATE
LN [scale_factor]
– Natural Logarithm
Arguments
[scale_factor] - FLOAT Applied scaling to prevent integer round-off (default=1)
Description
Take the natural log of the data in the image buffer. Scale the result by scale_factor.
See Also
SQUARE, SQRT, POWER
OMA for Mac OS X User’s Guide
MAKNEW n m
21
– Resize the Current OMA Image Buffer
Arguments
n - INTEGER Width of the new image
m - INTEGER Height of the new image
Description
Change the resolution of the data in the current data buffer to
be n by m pixels. Linear interpolation is performed.
Example
MAKNEW 576 384
See Also
FRAME
MATCH image2 – Spatially Match 2 Different Images
Arguments
nd
image2 - FILE Filename of 2 OMA Image
Description
This command is used to create matching image pairs from images taken with different
magnification, displacement, and rotation. The first image is assumed to be in the current
image buffer. "image2" specifies the name of a file containing the second image. The
necessary image matching parameters are stored in an ascii text file and must be loaded with
the GETMAT command prior to executing the MATCH command. The command creates two
new images and stores them in files named Match_1 and Match_2. Image 1 should be the
lower resolution of the two.
Example
GET Image1
GETMAT matchfile
MATCH Image2
GET Match_1
SAVFIL Image1new
GET Macth_2
SAVFIL Image2new
;Get a file.
;Get matching parameters from file.
;Match the 2 files.
;Get output of Match command.
;Save as new filename.
;Get output of Match command.
;Save as new filename.
See Also
GETMAT
MIRROR
– Flip the Image Horizontally
Arguments
none
Description
Perform a left-right mirror image operation of the data in the current OMA Image Buffer.
See Also
INVERT, ROTATE
OMA for Mac OS X User’s Guide
MULSCA
22
– Multiply Image by Scalar Average Value
Arguments
none
Description
Mulitply the data array by the scalar value calculated with the GETSCA command. (Yale
Command.)
See Also
GETSCA, DIVSCA
NOISE avg rms – Create a noise image
Arguments
avg - FLOAT Average value of the new Image
rms - FLOAT Root Mean Square fluctuations of noise in new image
Description
Creates a noise image with the specified RMS and average values. The old data in the buffer
is destroyed but the new image has the same dimensions as the previous buffer.
POSITV
– Set Negative Pixel Values Equal to Zero
Arguments
none
Description
Sets all negative values in the image buffer to 0. Positive values are unaffected
POWER exp
– Square the OMA data buffer
Arguments
exp – FLOAT Exponent value
Description
Raise the data in the current image data buffer to the power of exp. Currently, no
overflow checking is done and the scale factor is ignored.
See Also
SQUARE, SQRT
OMA for Mac OS X User’s Guide
RECTAN ulx uly lrx lry
23
– Define an Image Sub-region
Arguments
ulx - INTEGER Upper left X co-ordinate of defined sub-region (0 -> width-1)
uly - INTEGER Upper left Y co-ordinate of defined sub-region (0 -> height-1)
lrx - INTEGER Lower right X co-ordinate of defined sub-region (0 -> width-1)
lry - INTEGER Lower right Y co-ordinate of defined sub-region (0 -> height-1)
Description
Specify a rectangular sub-region that calculations are to be done on. Used for commands that
operate on sub-regions of the image. Corners must be specified in the correct order ie.
ulx<lrx and uly<lry. The region must be at least 1 by 1.
Example
;define sub-region.
;calculate subregion statistics
;Save the subregion to file “junk”
RECTAN 12 34 543 633
CALC
KRECT junk
See Also
CALC, FILBOX, KRECT
RECTC width height
– Define a Central Image Sub-region
Arguments
width - INTEGER Upper left X co-ordinate of defined sub-region (0 -> width-1)
height - INTEGER Upper left Y co-ordinate of defined sub-region (0 -> height-1)
Description
Specify a rectangular sub-region of width by height that sits in the centre of the current OMA
Image. Used for commands that operate on sub-regions of the image
See Also
KRECT, RECTAN
ROTATE [value]
– Rotate the OMA Image
Arguments
[value] – FLOAT specifies the amount of rotation (in degrees).
Description
Rotates the data in the current image buffer. If no value is given the image is rotated counterclockwise 90 degrees. If a value is specified, the image is rotated counter-clockwise, by the
number specified in [value].
Example
ROTATE 30.7
See Also
INVERT, MIRROR
OMA for Mac OS X User’s Guide
SBACK
24
– Place OMA Image in the Background Buffer
Arguments
none
Description
Save the data in the current data buffer as a background to be used by the CORECT
command.
See Also
CORECT, SRESP
SMEAN
– Place OMA Image in the Response Buffer
Arguments
none
Description
Save the data in the current data buffer as a mean to be used by the FLUCT command.
See Also
FLUCT
SMOOTH [n,m]
– Rectangular Smoothing
Arguments
[n] - INTEGER width of smoothing filter in horizontal direction (optional)
[m] - INTEGER height of smoothing filter in vertical direction (optional)
Description
Performs an n x m smoothing operation on data in the current image buffer.
If only n is specified, an n x n smoothing is done;
with no argument, a 2 x 2 smoothing is performed.
For the smoothing operation to be perfectly centered on each data point, the arguments must
be odd.
Example
SMOO 3 will perform a 3 x 3 smoothing centered on each pixel.
See Also
SMOOG
OMA for Mac OS X User’s Guide
SQUARE
25
– Square the OMA data buffer
Arguments
none
Description
Square the data in the current image data buffer. Currently, no
overflow checking is done.
See Also
POWER, SQRT
SQRT
– Take the Square Root of the OMA data buffer
Arguments
none
Description
Take the square root of the data in the current image data buffer. The scale factor is ignored.
See Also
POWER, SQUARE
SRESP
– Place OMA Image in the Response Buffer
Arguments
none
Description
Save the data in the current data buffer as a response to be used by the CORECT command.
See Also
CORECT, SBACK
OMA for Mac OS X User’s Guide
26
Data Information Commands
MAX
- Determine and Print the Image Buffer Key Values
Arguments
none
Description
Determines and prints the minimum and maximum of the data in the current buffer to the OMA
Command Window.
This is useful for updating the values stored in variables %b, %l, etc before using them.
Example
LN 10
MAX
+ %b
; Modify the image in the buffer
; Update the min and max values
; Add the maximum to every pixel
See Also
VARIAB
WDATA n
- Write Data from the Buffer to the Screen
Arguments
n - INTEGER Number of Data Words to write to the screen
Description
Writes the first n pixels from the current image buffer to the OMA Command Window.
See Also
FWDATA
OMA for Mac OS X User’s Guide
27
Image Display Commands
ANIMAT [n]
- Create an Animation from Sequential Images
Arguments
[n] - INTEGER Number of times to repeat the animation (Default=1)
Description
Create an animation by sequentially copying all graphics windows into the currently active
window. Repeat the sequence abs(n) times. If n<0, the cycle is restarted from the first window
each time. If n>0, the sequence is from first to last back to first. At the end of the animation,
the currently active window is restored to its original state.
See Also
DISPLA
CMINMX n m
- Change the False-Color Scale
Arguments
n - INTEGER Pixel Intensity corresponding to minimum color value
m - INTEGER Pixel Intensity corresponding to maximum color value
Description
Specifies the minimum and maximum values in the data that correspond to the minimum and
maximum color or gray scale values. Specifying the values causes the "Auto Scale" feature to
be disabled. If the arguments are not given, the "Auto Scale" feature is enabled.
See Also
DISPLA, PALETT
DISPLA [name]
- Display the Current Image Buffer
Arguments
[name] - STRING Name of new window (Optional)
Description
Opens a window on the Macintosh screen and displays the contents of the current data buffer.
The color palette used can be determined by the PALETT command. The color minimum and
maximum are specified by the CMINMX command. There can be up to 9 image windows
open at one time. Windows can be resized, moved around the screen, and closed as in other
Macintosh applications. If the optional string is specified, the window will be named according
to the string.
See Also
CMINMX, ERASE, PALETT, PIXSIZ, NEWIND
OMA for Mac OS X User’s Guide
ERASE [n]
28
- Erase (Close) the Display Windows
Arguments
[n] - INTEGER Window Number to close (Default ALL)
Description
Closes the display window(s) opened using the DISPLA command. If no arguments are given
then all the display windows are closed. If a value n is specified, then only window number n
is closed. Note that the actual contents of the OMA image buffer are not affected at all.
See Also
DISPLA
KPLOTC [name]
- Plot the Image Buffer as a Contour-Plot
Arguments
[name] - STRING Name of new window (Optional)
Description
The same as the "Plot Contours" command. It causes the data in the current buffer to be
plotted according to the information in the "Set Contours" menu item.
See Also
KSURFC
KSURFC [name]
- Plot the Image Buffer as a Surface-Plot
Arguments
[name] - STRING Name of new window (Optional)
Description
Plots the data in the current image data buffer as a three-dimensional surface.
See Also
KPLOTC
OMA for Mac OS X User’s Guide
NEWIND [flag]
29
- Set the Behaviour of Image Display
Arguments
[flag] - BOOLEAN Flag to determine DISPLA behaviour (Default TRUE)
Description
If flag = 1 a new window will be opened for each DISPLA command. There can be a
maximum of 9 graphics windows open at one time. If there are already 9 windows open on the
screen, subsequent graphics commands will close the oldest window before opening a new
one.
If flag = 0, the results of DISPLA commands will be placed in the last-opened window. If no
window exists, a new one will be opened. If the size of the last-opened window is not
appropriate for the current scan parameters, the last-opened window will be closed and a new
window opened with the correct size.
See Also
DISPLA
PALETT [n]
- Select a Different Predefined Palette
Arguments
[n] - INTEGER Number of predefined OMA palette to use (Default=0)
Description
Specifies that the nth predefined color palette should be used to display images. There are a
few predefined palettes.
0 – False color palette
1 – Greyscale palette
2 – Red palette
3 – Green palette
4 – Blue palette
See Also
DISPLA, CMINMX
PIXSIZ [n]
- Set the Zoom Displaying Images
Arguments
[n] - INTEGER Number of Macintosh screen pixels to each data point (Default=1)
Description
Specifies the number of pixels on the Macintosh screen that will be used to represent each
data word in the current image buffer. PIXSIZ 1 associates one Macintosh screen pixel with
one data point. For n positive, PIXSIZ specifies that n pixels are to be used for each data
point. If n is negative, a reduced picture is displayed with only every nth data point from the
image data being displayed as one Macintosh pixel. (Good for large pictures and small
screens.)
See Also
DISPLA
OMA for Mac OS X User’s Guide
RULER [npix] [nunits] [units]
30
- Define the Image Dimensions
Arguments
[npix] - FLOAT Number of pixels in image
[nunits] - FLOAT Number of units corresponding to npix
[units] - STRING Name of the new unit values (Optional).
Description
Can be used to specify the number of pixels that correspond to any arbitrary length unit. An
optional string can be included to define the units (e.g., "mm" or "feet"). If no arguments are
given, the current scale factor will be printed. The scale factor defined with the RULER
command is used
(1) when printing lengths using the ruler tool in the status window,
(2) when reporting contour lengths generated by the "Plot Contours" menu command
(3) When reporting the x and y "centre of mass” using the CALC command or rectangle
tool in the status window.
Scale factor info is saved with data files and will be reloaded automatically when the files are
retrieved. To "undefine" a ruler, give only one argument.
Example
RULER 404.3 3.5 mm
RULER 0
; Define 404.3pixels equal to 3.5mm
; Undefine the ruler
See Also
CALC
SCAT [xsiz] [ysiz] [xmin] [xmax] [ymin] [ymax]- Create a Scatter-Plot
Arguments
[xsiz] - INTEGER Width of new scatter plot
[ysiz] - INTEGER Height of new scatter plot
Description
Displays a scatter plot from first and second half of current image. Size of scatter plot is
specified by xsize and ysize. Bin size is determined by the min and max values of each half.
SLIDES [name]
- Batch Display PICT Files to Screen
Arguments
[name] - FILE ASCII file containing the names of PICT files to be displayed.
Description
Click on the mouse to go to the next slide. The file prefix settings in GRAPHICS are used.
See Also
DISPLA, PREFIX, UPREFX
OMA for Mac OS X User’s Guide
31
Macro Commands
DMACRO [n] [command]
- Define an OMA Macro
Arguments
[n] - INTEGER OMA Macro line number (Optional)
[command] - STRING forming an OMA Command and Arguments (Optional)
Description
Prompts the user for lines of a command macro to be executed using the RMACRO
command. If the argument n is omitted, definition starts with line one. If [n] is specified,
definition begins with the nth line of the macro. To include numerical arguments that change
each time the macro is executed, %d can be inserted in the macro command at the location
where the number will be placed upon execution of the macro. If [command] is not present,
the program prompts for additional command lines until a null command is entered (i.e. <CR>
only). If the optional [command] is included on the same line, the text of [command]
replaces any command already existing at line n and no further command lines are solicited.
See Also
LMACRO, RMACRO
ECHO “string”
- Perform a Data Check
Arguments
“string” - STRING piece of text to be written to OMA Command Window
Description
Prints "string" during macro execution. "string" can be replaced with any of the macro
dummy arguments (e.g., ECHO %b).
EXECUT filename
- Execute an OMA Macro from File
Arguments
filename - FILE Name of OMA Macro File
Description
Reads OMA commands stored in the specified file into a special execute buffer and then
performs those commands. Unlike macros, these should not contain dummy numerical
arguments (%d). Uses MACRO data type paths and prefixes.
See Also
MACRO, RMACRO, PMACRO
OMA for Mac OS X User’s Guide
GMACRO filename
32
- Load an OMA Macro File
Arguments
filename - FILE Name of OMA Macro File
Description
Loads the contents of the specified file into the current macro buffer.
See Also
SMACRO
IMACRO [flag]
- Set Macro Interrupt Behaviour
Arguments
[flag] - BOOLEAN Can the macro be interrupted? (Default=1)
Description
Used for setting or clearing a flag which determines whether or not an executing macro can be
interrupted (using "cmd ."). If n = 0, interruption is not allowed. If n is non-0, it is. This can be
used from within a macro to ensure that certain sequences of commands are complete before
stopping the macro. (e.g., to be sure that the camera shutter is closed.)
INCMAC n
- Set the Increment Value for Macro Iteration
Arguments
n - INTEGER Increment Value
Description
Specifies that on each execution of a macro, values should be incremented by value n.
See Also
EXECUT, INCMAC, PMACRO, RMACRO
LMACRO
- Load an OMA Macro File
Arguments
none
Description
Lists the contents of the current macro buffer.
See Also
DMACRO
OMA for Mac OS X User’s Guide
LOOP var_name start end [step]
33
- Begin a Loop in a Macro
Arguments
var_name - STRING Name of Loop Variable
start - INTEGER Increment Value
end - INTEGER Final Loop value
[step] - INTEGER Increment Value for each Iteration (Default=1)
Description
Initializes a loop. The var_name can be any string of reasonable length. The variable takes
on the initial value specified by "start" and the commands within the loop are repeated until
the variable is >= "end". ( or <= "end" if step < 0) If [step] is not specified, a [step] of 1 is
assumed. The end of the loop is specified by the LOOPND command. Each LOOP must have
a corresponding LOOPND. To access the value of a loop variable, preceede variable_name
with "@". It is not wise to nest loops in macros.
Note: To signify the end of a variable name when it is followed by other characters, use a '\'
character.
Example
LOOP fnum 2 10 2
GET data@fnum
DISPLA
LOOPND
…
LOOP fnum 2 10 2
GET data@fnum\_corrected
DISPLA
LOOPND
See Also
LOOPND
LOOPND
- Specify the End of a Loop
Arguments
none
Description
Specifies the end of a loop initiated with the LOOP command.
See Also
LOOP
OMA for Mac OS X User’s Guide
MACRO [n] [m]
34
- Run the Current Macro Silently
Arguments
[n] - INTEGER Macro Start Value (Default=1)
[m] - INTEGER Macro End Value (Default=1)
Description
This Command is the same as RMACRO except that printing of intermediate output is
suppressed until the macro has finished.
See Also
EXECUT, INCMAC, PMACRO, RMACRO
PMACRO n
- Perform the Specified Iteration of a Macro
Arguments
n - INTEGER Macro Value, substitutes for %d.
Description
Executes commands in the current macro buffer with %d being replaced by the value n.
See Also
EXECUT, INCMAC, MACRO, RMACRO
RMACRO [n] [m]
- Run the Current Macro
Arguments
[n] - INTEGER Macro Start Value (Default=1)
[m] - INTEGER Macro End Value (Default=1)
Description
Starts executing commands in the macro buffer with %d being replaced first by value [n].
Subsequently, [n] is incremented by the amount specified in the INCMAC command (default
is 1). If the new numeric value is less than or equal to [m], the macro will be executed again.
See Also
EXECUT, INCMAC, MACRO, PMACRO
SETUP n
- Perform the Specified Iteration of a Macro
Arguments
n - INTEGER Macro Value, substitutes for %d.
Description
Executes commands in the current macro buffer with %d being replaced by the value n.
See Also
EXECUT, INCMAC, MACRO, RMACRO
SMACRO filename
Arguments
- Save the Current OMA Macro to File
OMA for Mac OS X User’s Guide
35
filename - FILE Name of OMA Macro File
Description
Saves the contents of the current OMA Macro buffer to the file specified by filename. The file
will be created if it doesn’t exist. The prefixes used are those for the MACRO data type.
SMACRO is also used to save commands to be used with the EXECUT command.
See Also
GMACRO
STRMAC string
- Load an OMA Macro File
Arguments
string - STRING Replaces %s in Macros And The Command Line
Description
Specifies that "string" is to be substituted for any "%s" found in macro or execute commands.
If no string is specified, the current string is printed to the OMA Command Window.
Dummy arguments in Macros or Execute files include the following:
%d a decimal digit
%s the string specified by the STRMAC command
%f last file name
%b maximum value (big)
%l minimum value (little)
%m multiplier (the current scale factor)
%t current date and time
%v an integer value that increments by a specified amount every time it is used
See Also
VALMAC
VALMAC [n] [m]
- Set the value of the %v Variable
Arguments
[n] - INTEGER %v Variable Start Value (Default=0)
[m] - INTEGER %v Variable End Value (Default=1)
Description
Resets the %v value to [n] with an increment of [m].
See Also
EXECUT, INCMAC, MACRO, RMACRO
OMA for Mac OS X User’s Guide
36
Particle Image Velocimetry (PIV) Commands
DA [npix]
- Display Autocorrelation Centered On The Cursor
Arguments
[npix] - INTEGER Zoom Factor (Default=1)
Description
Using the size specified by the PIVSIZ command, zoom in on the autocorrelation of the area of
the image centered on the cursor.
See Also
DFFT, PIVSIZ
DFFT [npix]
- Display Fourier Transform Centered On Cursor
Arguments
[npix] - INTEGER Zoom Factor (Default=1)
Description
Using the size specified by the PIVSIZ command, zoom in on the Fourier Transform of the area
of the image centered on the cursor.
See Also
DA, PIVSIZ
DZOOM [npix]
- Magnify a Portion of the OMA Image
Arguments
[npix] - INTEGER Zoom Factor (Default=1)
Description
Using the size specified by the current rectangle, zoom in on an area of the image centered on
the cursor. Zoom factor is npix (integer). This is good for getting a close-up of a sub-region of
a high-resolution image.
See Also
DISPLA, RECTAN
OMA for Mac OS X User’s Guide
FFT mode [scale_factor]
37
- Fourier Transform Operations
Arguments
mode - INTEGER Variable to Select FFT Operation
[scale_factor] - INTEGER Scale Factor Applied to Result (Default=1)
Description
mode = 0
mode = 1
mode = 2
mode = 3
mode = 4
mode = 5
mode = 6
mode = 7
mode = 8
return the magnitude scaled by scale_factor
return the real part scaled by scale_factor
return the imaginary part scaled by scale_factor
return inverse - input is real part scaled by scale_factor
return inverse - input is imaginary part scaled by scale_factor
return the log of the magnitude squared scaled by scale_factor
return the magnitude squared scaled by scale_factor
return the autocorrelation scaled by scale_factor
return inverse - input is a filter scaled by scale_factor
See Also
DFFT
MASK width height
- Set a Mask for Inverse FFT Operations
Arguments
width - INTEGER Width of Centered Mask Region
height - INTEGER Height of Centered Mask Region
Description
Make a "mask" for inverse fft operations. The central region of the current image with the width
and height specified will be set to 1. The area around the central region is set to 0. (See FFT
command option 8.)
See Also
FFT
PAIRS dx dy radius
- Count Particle Pairs in Image
Arguments
dx - INTEGER Horizontal Separation of Particle Pair
dy - INTEGER Vertical Separation of Particle Pair
radius - INTEGER Variation of displacement
Description
Find pairs of particles separated by dx, dy (to within radius) asssumes arrays exist that
contain image points and that the points lie within the bounds of the current image. The
rectangle is changed to correspond to the entire image.
See Also
PAIRPR, POINT
OMA for Mac OS X User’s Guide
PAIRPR
38
- Process Particle Pairs Statistics for Current Image
Arguments
none
Description
Process pair statistics for an entire image. Assumes that matching PIV and POINT have
already been calculated (e.g., via the PIV and POINTS or PNTMOS commands). Prints out
statistics corresponding to pairs for each velocity vector.
See Also
POINT, PIV, PNTMOS
PEAKIM peakval sum_area excl_radius
- Convert to a Peaks Only Image
Arguments
peakval - INTEGER Threshold to qualify as points
sum_area - INTEGER Size of Window to find Peaks
excl_radius - INTEGER Exclude Radius
Description
Process pair statistics for an entire image. Assumes that matching PIV and POINT have
already been calculated (e.g., via the PIV and POINTS or PNTMOS commands). Prints out
statistics corresponding to pairs for each velocity vector.
PIV sum_area excl_radius
- Perform Autocorrelation PIV
Arguments
sum_area - INTEGER Size of Window to find Peaks
excl_radius - INTEGER Exclude Radius is Minimum Particle Displacement
Description
Perform Autocorrelation PIV on the current OMA Image to determine a Velocity Vector Field.
The 6 strongest peaks in the Autocorrelation Image are determined and stored in the PIV
Vector Field. Correlation peaks are found using a Centroid hunting algorithm that scans the
autocorrelation image with windows sum_area by sum_area. A region of excl_radius around
the central autocorrelation peak is ignored.
PIV+ dx dy
- Add Constant Vector to Current OMA Vector Field
Arguments
dx - FLOAT X-component of Constant Vector
dy - FLOAT Y-component of Constant Vector
Description
Add a constant vector to the current OMA Vector Field.
See Also
PIV-, PIV* PIV/.
OMA for Mac OS X User’s Guide
PIV+ dx dy
39
- Subtract Constant Vector from Current Vector Field
Arguments
dx - FLOAT X-component of Constant Vector
dy - FLOAT Y-component of Constant Vector
Description
Subtract a constant vector from the current OMA Vector Field.
See Also
PIV+, PIV* PIV/.
PIV* scale
- Multiply the Current OMA Vector Field by a Scalar
Arguments
scale - FLOAT Scale Factor to apply to Current Vector Field
Description
Multiply the current OMA Vector Field by scale_factor.
See Also
PIV+, PIV* PIV/.
PIV/ scale
- Divide the Current OMA Vector Field by a Scalar
Arguments
scale - FLOAT Scale Factor to apply to Current Vector Field
Description
Divide the current OMA Vector Field by scale_factor.
See Also
PIV+, PIV* PIV*.
PIVADD filename
- Add Vector File to the Current OMA Vector Field
Arguments
filename - FILE Valid PIV File of same dimensions as the Current Vector Field
Description
Add a OMA Vector File to the current OMA Vector Field. filename must exist and must be the
same dimensions as the current vector field.
See Also
PIVSUB
OMA for Mac OS X User’s Guide
PIVALT flag
40
- Set the Interrogation Mode
Arguments
flag - INTEGER Variable which determines the effect of mouse clicks in a PIV image
Description
Used to alter or delete a point calculated by the PIV command. The value of flag deterines
what effect clicking the mouse in a PIV image will have.
mode = 0
Mouse clicks have no effect
mode = 1
Cycle through different peaks, rotate all other peaks up one position.
mode = 2
Delete the vector. Only displayed peak is set to zero, others remain.
mode = 3
Massage - Search for peak most similar to local average.
See Also
PIVPLT
PIVAVG
- Calculate Average Vector from Buffer
Arguments
none
Description
Calculates the Average vector over the Entire Vector Field.
See Also
PIVPLT
PIVBAD mag angle [replace]
- Automatically Correct Outliers
Arguments
mag
angle
[replace]
- FLOAT Allowed Variance in Magnitude Variation (in pixels)
- FLOAT Allowed Variance in Angle (in degrees)
- BOOLEAN Replace Vector by Interpolation? (Default=0)
Description
Find vectors which deviate more than mag in magnitude and angle in angle from those in
immediate neighbourhood. [replace] = 1 means outlier is replaced by a local average if a
suitable alternate peak is not possible.
See Also
PIVRMV, PIVSHT
OMA for Mac OS X User’s Guide
PIVCRS
41
- Perform Cross-correlation PIV Processing
Arguments
none
Description
Cross correlation PIV command. The second image is stored in the background image (use
the SBACK command).
See Also
PIV
PIVDIR
- Set Preferred Vector Direction
Arguments
none
Description
Alter PIV vectors to orient themselves in the preffered direction. The preferred direction is set
using option 4 of the PIVSET command.
Example
PIVSET 4 –y
PIVDIR
PIVPLT 3
; Set preffered direction
; Change vector directions
; Plot the vector field
See Also
PIVSET
PIVDIV
- Divide the Current OMA Vector Field by a Scalar
Arguments
none
Description
Divide the currently loaded vectors by scalar (image) file in buffer. The scalar field must have
the same dimensions (height x width) the same as the number of vectors in the field. (Note:
This is very different from the size of the original particle image).
See Also
PIVMUL
PIVGET filename
- Read a OMA Vector Field from File
Arguments
filename - Specifies the name of an existing OMA Vector file.
Description
Load PIV data from the file named filename. The DATA file type prefixes are used.
See Also
PIVMUL, PREFIX
OMA for Mac OS X User’s Guide
PIVINC n
42
- Set the Interrogation Region Offset
Arguments
n
- INTEGER Increment in pixels
Description
Specify the increment (in pixels) between successive samples in the PIV command
Example
PIVSIZ 32
PIVINC 16
PIV 3 1
; Set Interrogation Window Size
; Set increment to 50% of ROI
; Process the Vector Field
See Also
PIVSIZ, PIV
PIVLST
- Output the Vector Buffer to Screen
Arguments
none
Description
Write the value of the vector field to the OMA Command Window
See Also
VECIMG
PIVMUL
- Multiply the Current OMA Vector Field by a Scalar
Arguments
none
Description
Multiply the currently loaded vectors by scalar (image) file in buffer. This could be used to
apply a mask (scalar file with 1's and 0's) to the vector field. The scalar field must have the
same dimensions (height x width) the same as the number of vectors in the field. (Note: This is
very different from the size of the original particle image).
See Also
PIVMUL
PIVPLT [scale]
- Plot the Vector Field to the Screen
Arguments
[scale] - FLOAT Vector Display Size (Default=1)
Description
Plot the current PIV data, and scale vectors by [scale] without modifying values.
OMA for Mac OS X User’s Guide
PIVREF center peaks
43
- Plot the Vector Field to the Screen
Arguments
center - INTEGER New Center Pixel
peaks - INTEGER New Number of Stored Peaks
Description
Reformat the PIV data to have center as the center pixel, with peaks # of peaks.
PIVRMV mag angle [replace]
- Automatically Correct Outliers
Arguments
mag
angle
[replace]
- FLOAT Allowed Variance in Magnitude Variation (in pixels)
- FLOAT Allowed Variance in Angle (in degrees)
- BOOLEAN Replace Vector by Interpolation? (Default=0)
Description
Set to zero those vectors which deviate more than mag in magnitude and angle in angle from
those in immediate neighbourhood. [replace] = 1 means outlier is replaced by a local average
if a suitable alternate peak is not possible.
See Also
PIVBAD, PIVSHT
PIVRND dx dy max num
- Simulate a PIV image
dx - INTEGER Horizontal Diswplacement
dy - INTEGER Vertical Displacement
max - INTEGER Maximum Pixel Intensity
num- INTEGER Number of Particle Pairs
Description
Generate a simulated double-exposure PIV image
Example
PIVRND 1 4 4096 10000 ; Generate 12-bit PIV image of 10000 pairs
PIVSIZ 16
; Set Window to 16 pixels
PIVINC 8
; Set increment to 50% of ROI
PIV 3 1
; Process the Vector Field
PIVSAV filename
- Save a OMA Vector Field to File
Arguments
filename - Specifies the name of an OMA Vector file.
Description
Save PIV data to a file named filename. The DATA file type prefixes are used.
See Also
OMA for Mac OS X User’s Guide
44
PIVGET
PIVSET [mode] [arg1] […]
- Set OMA PIV
Arguments
[mode] – INTEGER Flag specifying variable to be changed
[arg1] - STRING First Argument passed.
[…] - STRING Subsequent Arguments
Description
Set the value of things used by the PIV command.
Example
PIVSET 3 3
PIVSET 4 +x
PIVSET 7 1
PIVSHT [exrad]
; Set Plot scale factor
; Set Preferred direction
; Set Conditional Processing to TRUE
- Remove Short Vectors
Arguments
[exrad]
- FLOAT Minimum Valid Vector Length
Description
Remove (Delete) vectors with a magnitude less that exrad.
See Also
PIVBAD, PIVRMV
PIVSIZ fftsiz
- Remove Short Vectors
Arguments
fftsiz - INTEGER Size of the FFT Interrogation Window
Description
Specifies the size of the FFT done in the PIV Processing. Older FFT Routines require fftsiz to
be some power of 2.
See Also
PIVINC
PIVSQR
- Take the Square Root of Each Vector Component
Arguments
none
Description
Get square root of each component of the currently loaded vectors.
See Also
PIVMUL
OMA for Mac OS X User’s Guide
PIVSUB filename
45
- Subtract a Vector File from the Current Field
Arguments
filename - FILE Valid PIV File of same dimensions as the Current Vector Field
Description
Subtract a OMA Vector File from the current OMA Vector Field. filename must exist and must
be the same dimensions as the current vector field.
See Also
PIVADD, PIVSUC
PIVSUC filename
- Conditional Subtraction
Arguments
filename - FILE Valid PIV File of same dimensions as the Current Vector Field
Description
Subtract a OMA Vector File from the current OMA Vector Field. filename must exist and must
be the same dimensions as the current vector field.
Only vectors which are non-zero are affected.
See Also
PIVADD, PIVSUC
PIVX
- Extract the X Component
Arguments
none
Description
Extract the X-component of the PIV Vector Field by setting the Y-component to zero.
See Also
PIVY
PIVY
- Extract the Y Component
Arguments
none
Description
Extract the Y-component of the PIV Vector Field by setting the X-component to zero.
See Also
PIVX
OMA for Mac OS X User’s Guide
POINTS clipval
46
- Store the centroids of all Points
Arguments
clipval - INTEGER Threshold Intensity to Qualify as a Point
Description
For all points with an intensity greater that clipval, find the centroid, area and integrated
intensity and store this information in memory. This information is used by PNTIMG.
See Also
PNTIMG
PNTIMG
- Replace Image Buffer with Points Image
Arguments
none
Description
Replace the image data by a points only image. Points must first be generated via the POINTS
command.
See Also
POINTS, PIVRND, PNTMOS
PNTMOS fraction
- Count the Points in a Large Image
Arguments
fraction - FLOAT Fraction of largest peak height used as a threshold
Description
Find the points (particle images usually) in a large image. The large image is treated as a
mosaic of smaller images (size specified by PIVSIZ). As in POINTS, the centroids of
connected areas are found, along with integrated intensities and areas. This information is
stored in memory. The clip value is determined as fraction of the range in each sub-image. For
example, a scale of 0.5 would use 50% of the largest peak height within the sub-image as the
clip value. Use the PIVSET command to enable the histogram clipping feature to exclude
erroneous minimum and values.
See Also
POINTS, PIVSIZ, PIVSET
OMA for Mac OS X User’s Guide
PNTMOS type
47
- Count the Points in a Large Image
Arguments
type - INTEGER Flag determining Image Type
Description
Replace the image data by a point-pair image. Points must first be generated via the POINTS
command and pairs generated via the PAIRS command.
type = 0
Assigns intensity/area
type = 1
Assigns total intesity
type = 2
Assigns ratio of intensities
See Also
POINTS, PAIRS, PNTIMG, PIVRND
PRINFO
- Count the Points in a Large Image
Arguments
none
Description
Provide info on point pairs. Points must first be generated via the POINTS command and pairs
generated via the PAIRS command.
See Also
POINTS, PAIRS
VECIMG [n]
- Convert Vector to Scalar (OMA) Image
Arguments
[n] - INTEGER Scale Factor (Default=1)
Description
Record the vector magnitudes (scaled by n) in the image buffer.
See Also
VECIMX, VECIMY
OMA for Mac OS X User’s Guide
VECIMX [n]
48
- Convert X-Component to Scalar (OMA) Image
Arguments
[n] - INTEGER Scale Factor (Default=1)
Description
Record the X-component of the velocity (scaled by n) in the image buffer.
Example
; Set Plot scale factor
; Extract X-component
; Convert to OMA Image scaled by 10
PIVG %s%d
PIVX
VECIMG 10
or
PIVG %s%d
VECIMX 10
; Set Plot scale factor
; Convert X-component to OMA Image scaled by 10
See Also
VECIMG, VECIMY
VECIMY [n]
- Convert Y-Compenent to Scalar (OMA) Image
Arguments
[n] - INTEGER Scale Factor (Default=1)
Description
Record the Y-component of the velocity (scaled by n) in the image buffer.
See Also
VECIMG, VECIMX
VORTIC [scale]
- Calculate 2-D Vorticity
Arguments
[scale] - INTEGER Scale Factor (Default=1)
Description
Calculate Vorticity using the method from Reuss et al. – circulation around a closed contour
surrounding each point. Scaled by [scale].
See Also
VORT2
VORT2
[scale]
- Calculate 2-D Vorticity
Arguments
[scale] - INTEGER Scale Factor (Default=1)
Description
Calculate Vorticity using simple difference method Scaled by [scale].
See Also
VORTIC
OMA for Mac OS X User’s Guide
3-D Array Commands
3DDELE
- Delete the 3D Array
Arguments
none
Description
Delete the 3D Data Arrayy built up with 3DSTOR commands
See Also
3DSTOR, 3DYZ, 3DXZ
3DSTOR
- Store Current Image as Next Layer in a 3D Array
Arguments
none
Description
Store the current image as the next slice of a 3D array.
Example
LOOP n 1 500
GET %s@n
3DSTOR
LOOPND
3DYZ %v
SAV %s_slice
3DDELE
; Start Loop 500 times
; Get a File
; Place in 3D Array
; End of Loop
; Take the %v-th YZ slice
; Save the Slice
; Delete Array
See Also
3DDELE, 3DYZ, 3DXZ
3DXZ n
- Get the n-th XZ Slice
Arguments
n - INTEGER Number of the XZ Slice
Description
Get the n-th X-Z slice of the 3D Data Array
3DYZ n
- Get the n-th YZ Slice
Arguments
n - INTEGER Number of the YZ Slice
Description
Get the n-th Y-Z slice of the 3D Data Array
49
OMA for Mac OS X User’s Guide
50
CCD Control Commands
ASK command
Sends a command to the CCD controller and expects that a reply will
be given. The ASK command receives and prints ASCII data from the
CCD controller until the GPIB interface times out.
CCD x y
Specifies that the detector is a CCD and therefore has an additional
80 word header preceeding the data. The maximum width is x and maximum
height is y.
CONECT [n]
Establishes a connection with the CCD controller via the GPIB interface.
This command should be issued before any other CCD commands are given.
Currently, this command will allow connection to either Photometrics
CC200 or Photometrics Star I controllers. If n is specified, the program
tries to connect to n CC200 controllers at different GPIB addresses.
This allows multiple detectors to be controlled by a single computer/GPIB
interface.
RECEIV
Receives image data from the CCD detector and places it in the image
data buffer.
RUN
Sends the current image format, as specified by CHANEL, TRACKS, DX,
DY, X0 and Y0, to the CCD controller.
SEND command
Sends commands to the CCD controller. This can be used to transmit
ASCII commands directly to the CCD controller.
SYNCH flag
flag = 1 specifies that the computer and CCD controller are to operate
in synchronous mode. The computer will wait until commands sent to
the CCD controller are completed before sending further CCD commands.
If flag = 0, the computer prompts for additional commands as soon as
commands have been sent to the CCD.
TRANSF
Sends the data in the current data buffer to the display memory in
the CCD controller. It is assumed that the CCD format is the same as
that specified in the computer (this can be ensured by first issuing a
OMA for Mac OS X User’s Guide
RUN command).
FLUSH
Waits until one of the following occurs: Either data is received from
the CCD detector or the controller times out waiting for data. This
is used to get rid of unwanted data returned to the computer by the
CCD controller.
ST6 [subcommand] [args]
This command is for interfacing with the Santa Barbera Instruments
Group ST6 detector. See release notes in "Read Me" for details.
Detector Format Commands
CHANEL n
Specifies that n channels (or columns) are to be scanned.
COLUMN n
Specifies that n channels (or columns) are to be scanned.
DX n
Specifies the number of detector pixels (not display screen pixels) to
be grouped (or binned) in the X direction.
DY n
Specifies the number of detector pixels (not display screen pixels) to
be grouped in the Y direction.
GWINDO
Moves the contents of the current display window into the image data
buffer. This can be used to get an OMA data representation of images
available as a Macintosh graphics window. The resulting values will
be in the range 1-251.
GIMAGE
Like "GWINDO" except that the contents of the off-screen copy of the
current display window are moved into the image data buffer. This can
be used to get the entire picture when the data in the window does not
fit onto the screen. The resulting values will be in the range 1-251.
LIST
Lists the current detector parameters and log block.
LOG [n] [comment]
Adds a comment to the comment buffer at line n. If n is not
51
OMA for Mac OS X User’s Guide
specified, the comment is added to the beginning of the comment
buffer. If "comment" is not present, the program prompts for additional
comment lines until a null comment is entered (i.e. <CR> only). If the
optional "comment" is included on the same line, the text
of "comment" replaces any comment already existing at line n and no
further comment lines are solicited.
SIT
Specifies that the data format is that appropriate for the SIT vidicon
detector. Image data is stored to files in 1s complement format.
There is no 80 word header at the beginning of the data area. This
option is included for compatibility with previous SIT data sets.
TRACKS n
Specifies that n tracks (or rows) should be read from the detector.
ROW n
Specifies that n tracks (or rows) should be read from the detector.
X0 n
Specifies that the detector is to be read out starting at channel n.
Y0 n
Specifies that the detector is to be read out starting at track n.
SFORM n
Save the current camera format as format n. n is in the range 0-7.
UFORM n
Restore camera format n previously saved using the SFORM command.
File Input/Output Commands
GET filename
Loads the data from the specified file into the current image data
buffer. The "Get Data Files" prefix and suffix are used.
KRECSV [filename]
Saves a subset of the current data buffer in a specified file. The
subset is specified by the selection rectangle displayed on the
screen. The rectangle is selected with the "Show Selection Rectangle"
command under the edit menu. If no filename is specified, a dialog
52
OMA for Mac OS X User’s Guide
53
window will prompt for one.
KWINDO filename
Saves the current window as a PICT file with the specified filename.
UPREFX type
Force use of prefix/suffix specified by 'type.' Possible
cases for 'type' include the following:
s Use Save File prefix and suffix
g Use Get File prefix and suffix
d Use Default prefix and suffix
KNEWSB [filename]
The same as the open scrapbook menu command. It opens the specified
file as a scrapbook. If no filename is specified, a dialog window
will prompt for one.
KADDSB
Appends the picture in the current window to the scrapbook file
previously opened by the KOPENW command or the "Open Scrapbook" menu
item.
KKLOSE
Closes the file previously opened with the "Open Scrapbook" command.
OPENFL flag
flag=1 specifies that files opened with the GET and COMPOS commands
should not be closed after the first data set is read in, but left
open. Subsequently, GET or COMPOS commands can be executed with no
argument, causing the next in a series of images stored in the
single file to be read into the data buffer. flag=0 disables this
option and is the default mode.
PREFIX [fileprefix]
Specifies a "prefix" to be added to all filenames accessed through
keyboard commands. This can be used to specify a default "disk:
folder:subfolder:". If no prefix is specified, a null prefix is
used.
SAVE filename
Saves the current data buffer to the specified file.
SUFFIX [filesuffix]
OMA for Mac OS X User’s Guide
54
Specifies a "suffix" or extension to be added to all filenames
accessed through keyboard commands. If no suffix is specified, a null
suffix is used.
FWDATA filename
Writes the data in the current buffer as a text file. Only data
values are written -- no header information is included. One integer
is written per line. These files can be opened by WORD, EXCEL, etc.
GETFIT filename
Loads an image file in FITS format into the current image data
buffer.
GETPIC filename
Opens an image file in PICT format. It is not automatically moved to
the image buffer. Use GWINDO if you want this.
SAVPIC filename
Writes the data in the current buffer as a pict file.
SAVSET
Saves the current settings as OMA Settings.
GETSET
Gets settings named OMA Settings.
CREATE filename
Opens a file with the specified name, saves the current data and
format information, and leaves the file open. Subsequently, the
CONCAT command can be used to add more data to the open file.
CONCAT
Saves the current data buffer to the file opened with the CREATE
command.
CLOSE
Closes the file opened with the CREATE command.
COMPOS filename
Create a composite image by appending the data in the specified file
to that which exists in the current image buffer. The width of the
specified file must be the same as that of the current image. The
OPENFL command works in conjunction with the COMPOS command in the
same way that it does with the GET command.
OMA for Mac OS X User’s Guide
55
OMA for Mac OS X User’s Guide
56
Line-Out Commands
For some applications, it is desirable to reduce the two-dimensional images
obtained from the detector to one or more one-dimensional arrays. Examples
are for streak camera readout or spectrographic data. The Lineout Commands
are designed to streamline this operation.
The Line Out menu and several keyboard commands have been added to implement
these features.
Line Out Templates
The regions of the two-dimensional image which are to be summed in one
direction and converted into one-dimensional arrays are specified in a Line
Out Template which is set up using the Template menu selection. A dialog
box is presented which allows the user to specify regions graphically or by
typing the coordinates of the upper left and lower right corners of the
region. Up to 30 regions can be specified in a single template. Each region
can be labeled with a 15 character label. Line Out Templates can be saved
to files or loaded from files. The information is stored in standard text
format and can be edited with any word processor. Each region can be summed
in either x or y direction. Check boxes allow the start and of end of
regions to be aligned with the first Line Out specified.
An example of the text from a Line Out Template follows:
OMA Line Out Template
6
hydrogen
11
4
74
11
methane
11
15
74
23
Nitrogen
11
25
74
33
oxygen
11
35
74
45
CO2
11
45
74
49
Rayleigh
11
55
74
65
0
0
0
0
0
0
The first line of text is included to ensure that the text is indeed a
lineout template and not some other text file.
The second line of text gives the number of Line Outs in the template.
OMA for Mac OS X User’s Guide
57
Each Line Out specification consists of two lines of text:
The first is a label of up to 15 characters
The second consists of 5 numbers separated by tabs for spreadsheet
compatibility:
x0
y0
x1
y1
sum_direction_flag
x0 y0 are the upper left corner
x1 y1 are the lower right corner
sum_directio_flag = 0 --> sum in y; the array is in x
sum_directio_flag = 1 --> sum in x; the array is in y
Note that a proper Line Out should have x0 < x1 and y0 < y1.
Enabling the "Show Boxes" checkmark under the Line Out menu causes the
current Line Out regions to be drawn whenever a display command is executed.
They will also be saved in graphics windows if this feature is enabled.
LINCAL
Calculate line outs specified by the current Line Out Template
using the data in the current image buffer. Line Outs calculated
previously are discarded.
LINGET n [multiplier]
Move the nth Line Out (calculated by LINCAL) into the current data
buffer. The previous contents of the data buffer are lost. Since
the integrated data may be larger than allowed by the 16 bits of
the image buffer, appropriate scale factors are calculated. If the
optional multiplier is included, the results are multiplied by that
factor before being moved to the data buffer. This could be used
to retain small differences that might be lost when normalization
is done. (See LINORM command.)
LINORM flag
If flag = 1, then the results returned by LINGET are normalized
to the number of lines integrated over. If flag = 0, no
normalization is done.
LTSAVE filename
Save the currently defined Line Out Template in the specified file.
LTLOAD filename
Open a Line Out Template file with the specified name.
OMA for Mac OS X User’s Guide
58
LINSTA
Print statistics (ave., rms fluctuation, etc.) for the regions
specified in the current Line Out Template.
LINSSB n fileneam
Save the nth Line Out subregion in a file with the specified name.
Miscellaneous Commands
EXIT
Terminates execution of a program.
CAMERA n
digitizes and displays n frames from the Data Translation frame
grabber.
HELP [command name or fragment]
If a command name is given, a brief explanation of the command is
printed in the command window. If only part of the command is given,
a description of all commands that match the command fragment is
printed. All help information is from the file "OMA HELP." If no
argument is given, all command names are printed with no explanation.
Digital I/O and GPIB Commands
National Instruments NB-DIO-24 or NB-DIO-32 digital I/O Boards can be used.
For the 24 bit board,
* stepper motor foreward direction:
Port C bit 0.
* stepper motor backward direction:
Port C bit 1.
* OUTPAR command: Port C bits 0-7.
* WAITHI command: Port B bit 0.
For the 32 bit board,
* stepper motor foreward direction:
Port A bit 0.
* stepper motor backward direction:
Port A bit 1.
* OUTPAR command: Port A bits 0-7.
* WAITHI command: Port C bit 0.
OUTPAR n
Sends the 8 bit parallel value n to the output port.
FORE n
OMA for Mac OS X User’s Guide
59
Sends n 30 Hz TTL pulses to output port bit 0.
BACK n
Sends n 30 Hz TTL pulses to output port bit 1.
WAITHI
Wait until input port bit 0 is TTL high.
GPIBDV n
Selects the nth gpib device. Used to control multiple CCDs.
GPIBTO flag
GPIB time out flag. If set, gpib time out will be
set. Otherwise, no timeout is set.
DELAY n
Waits for n ticks (1 tick = 1/60 sec) before performing any
further commands.
Menu Commands
All commands beginning with the letter k have menu selection items
associated with them. (The second letter of the command is the command-key
code associated with the menu item. Thus, these commands can be invoked three
ways: 1) By menu selection, 2) by the associated command-key code, or 3) by
typing the "k" command, which is echoed in the command window. The reason for
including this option is so that these functions can be performed in a macro.