(Still a newbie, but more knowledgeable than before)
I am having trouble reading images from a only few files out of a series
of files. The image file info is below.
The "xxxx.fpf" files consist of a header followed by a matrix of single
precision IEEE floating-point values, each representing one point of the
image. A C-style description of the header layout can be found in the
header file fpfimg.h, available in the installation directory. The image
point values are stored starting from the top left corner, row by row.
(The following line is from the header file referred to above)
Float 32 bit IEEE floating point number, sign + 23 bit mantissa +
8 bit exponent,Representing numbers in the range +/- 1038
My code boils down to this:
c4f =: _1 & (3!:5) NB. 4 chars to float
dat=: freads fn NB. reads the file
i1=: (pixeloffset)}. dat NB. drop header
i2=:c4f {.i1 NB. converts to float
This seems to work on 43 files, but on the 44th file, I get a length
error. Looking at i1, it is not mod 4. When I either curtail it to be
mod 4 or pad it to be mod 4, it reads but the image looks like an old TV
with the horizontal hold mis-set.
To add to the confusion, the viewing software from the vendor reads all
the files wonderfully. So I am guessing I am doing something wrong.
Any suggestions?
Dave Porter
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