NAME

pjrec - reconstruction from projections

SYNOPSIS

pjrec projection-file image-file nx-image ny-image [OPTIONS]

DESCRIPTION

pjrec takes projection data from raysum-fileP and produces an (IF) image file image-file, of size nx-image by ny-image pixels, containing the reconstructed image.

OPTIONS

pjrec accepts the following options, which control the reconstruction algorithm:

--interp: Interpolation method during backprojection

nearest: Nearest neighbor interpolation
linear: Linear interpolation

--preinterpolate: Preinterpolation factor (default = 1). Used only with frequency-based filtering
--filter: Filter name

abs_bandlimit: Abs * Bandlimiting (default)
abs_sinc: Abs * Sinc
abs_cosine: Abs * Cosine
abs_hamming: Abs * Hamming
shepp: Shepp-Logan
bandlimit: Bandlimiting
sinc: Sinc
cosine: Cosine
triangle: Triangle
hamming: Hamming

--filter-method: Filter method before backprojections

convolution: Spatial filtering (default)
fourier: Frequency filtering with discete fourier
fourier_table: Frequency filtering with table lookup fourier
fft: Fast Fourier Transform

--zeropad n: Set zeropad level (default = 0). set n to number of powers to two to pad
--filter-generation: Filter Generation mode

direct: Use direct filter in spatial or frequency domain (default)
inverse_fourier: Use inverse fourier transform of inverse filter

--backproj: Backprojection Method

trig: Trigometric functions at every point
table: Trigometric functions with precalculated table
diff: Difference method
diff2: Optimized difference method (default)
idiff2: Optimized difference method with integer math
idiff3: Highly-optimized difference method with integer math

--filter-param: Alpha level for Hamming filter
--trace: Set tracing to level:

none: No tracing (default)
console: Text level tracing

--verbose Turn on verbose mode
--debug Turn on debug mode
--version Print version
--help Print a terse help message

AUTHORS

Kevin Rosenberg, M.D. <kevin@ctsim.org>

HISTORY

CTSim was begun in 1983 using MS-DOS and an EGA display adapter. In 1999 it was ported to GNU/Linux and later ported to Microsoft Windows.