gpiv_imgproc (1)

gpiv_imgproc [-b N] [--filter N] [-h | --help] [-p | --print] [-o N | --operation N] [-t N | --threshold N] [-w N] [-v | --version] [filename] < stdin > stdout

gpiv_imgproc processes, filters or converts images in order to improve the interrogation for Particle Image Velocimetry. gpiv_smooth: smoothing filter, gpiv_hilo : high-low filter, gpiv_clip: clipping, gpiv_fft: Fast Fourier Transform, gpiv_invfft: Inverse Fast Fourier Transform, gpiv_highpass: high-pass filtering gpiv_getbit: get bit bumber. gpiv_mktestimg: generates test image-pair for PIV

The parameters read from the configuration resources (containing the key GPIV_IMGPROC) may be overruled by the command line options, as explained below.

-b N

In case of using gpiv_getbit N denotes the bit number [0, .., 7]

--filter N

Image filter to be applied: make test image (N=0), smoothing (N=1), high-low filtering (N=2), clipping (N=3), fft (N=4), inverse fft (N=5), lowpass filter (N=8), highpass filter (N=9), getbit (N=10).

-h | --help On-line help

-o N | --operation N In case of using gpiv_smooth: set pixel equal to the mean of the window value (N0), subtract mean from from pixel (N1) add (N2), multiply (N3) or divide (N4)

-t N | --threshold N In case of using gpiv_clip: threshold value to be set to zero

-v | --version Print version information on standard output, then exit successfully.

-w N window size (default: 15)

filename Input image filename. Overrides stdin and stdout with the full filename of the image. Output will be written to filename.png. Parameters are stored in filename.par and may be used for future use by including them in ./gpivrc. If stdin and stdout are used, the input is expected to be a PNG formatted image.

gpivtools

Gerber Van der Graaf