AFNI program: imcat
Output of -help
Usage: imcat [options] fname1 fname2 etc.
Puts a set images into an image matrix (IM)
montage of NX by NY images.
The minimum set of input is N images (N >= 1).
If need be, the default is to reuse images until the desired
NX by NY size is achieved.
See options -zero_wrap and -image_wrap for more detail.
++ Options for editing, coloring input images:
-scale_image SCALE_IMG: Multiply each image IM(i,j) in output
image matrix IM by the color or intensity
of the pixel (i,j) in SCALE_IMG.
-scale_pixels SCALE_PIX: Multiply each pixel (i,j) in output image
by the color or intensity
of the pixel (i,j) in SCALE_IMG.
SCALE_IMG is automatically resized to the
resolution of the output image.
-scale_intensity: Instead of multiplying by the color of
pixel (i,j), use its intensity
-gscale FAC: Apply FAC in addition to scaling of -scale_* options
-rgb_out: Force output to be in rgb, even if input is bytes.
This option is turned on automatically in certain cases.
-res_in RX RY: Set resolution of all input images to RX by RY pixels.
Default is to make all input have the same
resolution as the first image.
-respad_in RPX RPY: Like -res_in, but resample to the max while respecting
the aspect ratio, and then pad to achieve desired
-pad_val VAL: Set the padding value, should it be needed by -respad_in
to VAL. VAL is typecast to byte, default is 0, max is 255.
-crop L R T B: Crop images by L (Left), R (Right), T (Top), B (Bottom)
pixels. Cutting is performed after any resolution change,
if any, is to be done.
-autocrop_ctol CTOL: A line is eliminated if none of its R G B values
differ by more than CTOL% from those of the corner
-autocrop_atol ATOL: A line is eliminated if none of its R G B values
differ by more than ATOL% from those of line
-autocrop: This option is the same as using both of -autocrop_atol 20
and -autocrop_ctol 20
NOTE: Do not mix -autocrop* options with -crop
Cropping is determined from the 1st input image and applied to
to all remaining ones.
++ Options for output:
-zero_wrap: If number of images is not enough to fill matrix
solid black images are used.
-white_wrap: If number of images is not enough to fill matrix
solid white images are used.
-gray_wrap GRAY: If number of images is not enough to fill matrix
solid gray images are used. GRAY must be between 0 and 1.0
-image_wrap: If number of images is not enough to fill matrix
images on command line are reused (default)
-rand_wrap: When reusing images to fill matrix, randomize the order
in refill section only.
-prefix ppp = Prefix the output files with string 'ppp'
Note: If the prefix ends with .1D, then a 1D file containing
the average of RGB values. You can view the output with
-matrix NX NY: Specify number of images in each row and column
of IM at the same time.
-nx NX: Number of images in each row (3 for example below)
-ny NY: Number of images in each column (4 for example below)
Example: If 12 images appearing on the command line
are to be assembled into a 3x4 IM matrix they
would appear in this order:
0 1 2
3 4 5
6 7 8
9 10 11
NOTE: The program will try to guess if neither NX nor NY
-matrix_from_scale: Set NX and NY to be the same as the
SCALE_IMG's dimensions. (needs -scale_image)
-gap G: Put a line G pixels wide between images.
-gap_col R G B: Set color of line to R G B values.
Values range between 0 and 255.
Example 0 (assuming afni is in ~/abin directory):
Resizing an image:
imcat -prefix big -res_in 1024 1024 \
imcat -prefix small -res_in 64 64 \
aiv small.ppm big.ppm
Stitching together images:
(Can be used to make very high resolution SUMA images.
Read about 'Ctrl+r' in SUMA's GUI help.)
imcat -prefix cat -matrix 14 12 \
Stitching together 3 images getting rid of annoying white boundary:
imcat -prefix surfview_pry3b.jpg -ny 1 -autocrop surfview.000.jpg
Example 20 (assuming afni is in ~/abin directory):
imcat -prefix bigcat.jpg -scale_image ~/abin/afnigui_logo.jpg \
-matrix_from_scale -rand_wrap -rgb_out -respad_in 128 128 \
-pad_val 128 ~/abin/funstuff/face_*.jpg
aiv bigcat.jpg bigcat.jpg
Crop/Zoom in to see what was done. In practice, you want to use
a faster image viewer to examine the result. Zooming on such
a large image is not fast in aiv.
Be careful with this toy. Images get real big, real quick.
You can look at the output image file with
afni -im ppp.ppm [then open the Sagittal image window]
This page auto-generated on
Mon Apr 22 00:37:08 EDT 2019