destreak -- Remove streaks from Helium 10830 grams
destreak input_image output_image
- Image to be destreaked.
- Name to give destreaked output image (must be a separate image).
- Temporary image used for pixel storage between destreak passes.
- Flag to signal program that it should produce verbose output.
- threshold = 4
- Squibby brightness threshold to use in determining limb points.
The helium 10830 grams as taken by the vacuum telescope have horizontal streaks caused by the detecting apparatus. Destreak removes these streaks and the limb darkening using a two pass procedure. First, for each diode, a function of the form a + b*r**4, where r is the radius from disk center and a, b are parameters, is fit to the intensity distribution and is then subtracted from the data. Then a spatial filter is applied to the result and the final image is written to disk. The full disk images are 2048 x 2048 and are taken using a 512 diode array which is scanned from west to east across the solar disk 4 times. Thus, data from a particular diode consists of four lines of the image.
1. To destreak "image1", put the output in "image2", put the temporary image in "temp2", and see verbose output, the command would be:
vt> destreak image1 image2 temp2 v+