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diff --git a/pkg/proto/doc/irafil.hlp b/pkg/proto/doc/irafil.hlp new file mode 100644 index 00000000..be4f603b --- /dev/null +++ b/pkg/proto/doc/irafil.hlp @@ -0,0 +1,106 @@ +.help irafil mar86 proto +.ih +NAME +irafil -- converts a binary file containing pixel values to an IRAF image +.ih +USAGE +irafil input nrows ncols +.ih +PARAMETERS +.ls input +the input file names to be converted +.le +.ls nrows +the number of rows of data in the image +.le +.ls ncols +the number of columns of data in the image +.le +.ls bits = 16 +the number of data bits per pixel. This must be either 8 or 16 +.le +.ls signed = yes +the pixels are assumed to be signed integers if the bits parameter is 16, +and unsigned if the bits parameter is 8. If signed is set to no, then +the 16 bit pixels will be treated as unsigned integers and the resultant +image will be of type long integers. +.le +.ls tb_flip = no +This parameter allows the image to be "top-to-bottom" flipped during +conversion. +.le +.ls skip = 0 +the number of bytes to skip prior to reading pixel data. This allows +skipping of header data which is otherwise not translatable and would +be confused with the pixel data. +.le +.ih +DESCRIPTION +The specified files are read as integers and converted to IRAF images. +The specified number of header bytes will be skipped, and the specified +data format, 8 or 16 bit pixels, at the rate of ncols by nrows will be +read. Signed data or 8 bit data will be placed into images having data +type short. Unsigned 16 bit pixels will be converted into images of +type long. + +The resultant images will be assigned the same name as the input file, +but with ".i" appended to indicate IRAF format. + +The tb_flip parameter should be set to yes when converting the "snap" +format files from the Compaq image display station, or other devices +which refer to the first row as inverted from the usual IRAF notation. + +This utility is capable of converting a large number of strange +image formats to IRAF images. By skipping any initial header, and specifying +a value for ncols equal to either the row length of the image, or the +number of pixels used in the foreign internal format, almost any +16-bit format can be read. For example, FORTH pictures can be read +by skipping the initial 2048 bytes and reading the pixels assuming +a row length of 1024, even if the actual row length is shorter. There +will be garbage pixels at the end of each row which can be trimmed +with IMCOPY using picture sections. An absurd example is to read an +IRAF pixel file by skipping 1024 bytes and reading with a row length of +1024 [at least for the 800 pixel image I tried]. + +Since no byte swapping is performed, a foreign tape format must be byte swapped +if necessary prior to using IRAFIL. This may be done with REBLOCK in the +dataio package. +.ih +EXAMPLES + +1. Say you've deleted your header file to an IRAF image. The pixel file +is pix3034x. Assuming the pixels are short integers, the image is +10 rows by 800 columns: + +.nj +.nf +lo> irafil pix3034x 10 1024 skip=1024 +lo> imcopy pix3034x.i[1:800,*] phoenix +.fi +.ju + +The first line creates the IRAF image pix3034x.i which is readable +by IRAF tasks, but has 1024 pixels per row. The real image only +has 800 pixels per row, but we had to read it this way because of the +way pixels are stored in IRAF images. So we IMCOPY the good part of +the picture to the new IRAF image we call phoenix. + +2. To read the "snap" format pictures from the Compaq station: + +.nj +.nf +lo> irafil m82.snp 512 512 tb_flip+ bits=8 +.fi +.ju + +This will create the IRAF image m82.snp.i which can then be run +through CRTPICT to make a Dicomed hardcopy. +.ih +TIME REQUIREMENTS +.ih +BUGS +There is no way to explicitly specify the output image name. +.ih +SEE ALSO +binfil,imcopy,reblock +.endhelp |