Name
pixcut — extract a pix file from another pix file
Synopsis
pixcut [-v ] [-a ] [-# num_bytes] [-C red/green/blue] [-s in_square_size] [-w in_width] [-n in_height] [-S out_square_size] [-W out_width] [-N out_height] [-x horizontal] [-y vertical] [infile]
DESCRIPTION
pixcut will extract a color pix(5) format file from another pix(5) format file.
The
-w
and
-n
flags specify the input file width and number of scan lines in pixels.
They can both be set to the same value via
-s.
Unspecified dimensions default to 512 pixels.
The
-W
and
-N
flags specify the output file width and number of scan lines in pixels.
They can both be set to the same value via
-S.
Unspecified dimensions default to 512 pixels.
The
-a
flag requests that the program attempt to autosize the input file. Autosizing
only works with files; pipes can not be autosized.
The
-v
flag requests verbose mode. When verbose mode is selected the program
will display information on default background output if any background
is generated.
The
-x
and
-y
flags set the horizontal and vertical offsets from the lower left corner
to use for extracting
the image. By default both are set to 0 (zero).
The
-#
flag specifies the number of bytes (default is 3).
The
-C
flag is used to set the background color of the output file. If the
output file is larger than the input file or if the corners of the output
file do not reside within the bounds of the input file, the program will
output pixels of background color for those locations.
First quadrant coordinates and file storage formats are used.
EXAMPLES
The command
pixcut -S256 file1.pix > file2.pix
will extract the lower left quadrant of "file1.pix" and place it in file2.pix.
The command
pixcut -S256 -x128 -y128 file1.pix >file2.pix
will extract the center of the 512x512 input file (file1.pix) and place it in file2.pix.
The command
pixcut -x -1 file1.pix >file2.pix
will shift file1.pix one pixel to the right. If a raytrace was done with default parameters, the background (rays which do not intersect the model) are set to 0/0/1. Since pixcut will fill with 0/0/1 the net result is that the model image is shifted.
The command
pixcut -s1024 -x128 -y256 background.pix |
pixmatte -w512 -e image.pix =0/0/1 - image.pix |
pixpaste -s1024 -x128 -y256 background.pix - >new.pix
will extract the center 512x512 section of the 1024x1024 background image, composite that section with a foreground image, and then place the new composite image into the center of the background image.
The pixmatte command options instruct the program that for every pixel in image.pix which is equal (-e) to 0/0/1, output the corresponding pixel from standard input; and for all others, output the corresponding pixel from image.pix .
