Fork of the CSharpFITS package from http://voi.iucaa.in/voi/CSharpFITS.html

This fork basically adds a big performance boost for the common use case of writing a large, probably multi-dimensional, array of int or short values.

Files written by fpack -- and by Siril, SharpCap, astropy and the survey archives -- store the image as a binary table of compressed tiles. They read back as the image they hold, with no special handling by the caller:

var fits = new Fits("stack.fit.fz");
fits.ReadHDU();                          // the empty primary HDU fpack writes
var hdu = (ImageHDU)fits.ReadHDU();      // a CompressedImageHDU

hdu.BitPix;                              // -32
hdu.Axes;                                // { 3, 2160, 3840 }
hdu.Header.GetStringValue("OBJECT");     // the image's own metadata
hdu.GetChannel(0);                       // float[2160, 3840]

RICE_1, GZIP_1, GZIP_2, PLIO_1 and NOCOMPRESS are supported, along with quantized floating-point images under all three dithering methods. HCOMPRESS_1 is recognised but not decoded. Writing compresses nothing -- an HDU writes out as the plain image extension it presents, making a read plus a write a funpack. See CHANGELOG.md for the details and the limits.

FitsWriter writes one image onto any writable stream and FitsReader reads the first image of a file into the caller's planes, neither holding an array the size of the image (net10.0):

using (var writer = FitsWriter.CreateFile(path, FitsWriter.ImageHeader(16, width, height)))
{
    writer.Write<short>(samples);
    writer.Finish();
}

if (FitsReader.TryOpen(path, out var reader))   // false for a file it cannot read this way
{
    using (reader)
    {
        var plane = new float[reader.Width * reader.Height];
        reader.ReadPlane(0, plane);              // BZERO + BSCALE * stored, in single precision
    }
}

A file FitsReader declines (gzipped, tile-compressed, no image) is still read by Fits.

1.Souce code zip contains the visual studio 2005 project. (CSharpFITS_v1.1 folder) 2.Source code can be viewed with anything capable of reading ASCII. 3.Visual Studio 2005 is required to open and compile the project.

Refer docs folder for help on using the API..