Reading 16-bit images with pgmagick?
- From:
- John Pye
- Date:
- 2012-02-10 @ 22:08
Hi there
I have installed a copy of pgmagick 0.3.6 on my Ubuntu 11.10 machine.
It's the standard version that they've packaged in their software
repository.
I then tried loading a RAW image, using
from pgmagick import *
i = Image("DSC_0004.DSC")
i.depth()
but the output that I get is "8", when I expected to see 12-bit data (or
16, if it wants to pad it out).
If, on the other hand, I take the same raw image and use dcraw to
convert it to TIFF using
dcraw -T -4 DSC_0004.NEF
and then read the file using
http://www.lfd.uci.edu/~gohlke/code/tifffile.py.html
from tifffile import *
t = TIFFfile("DSC_0004.tiff")
t.pages[0].tags['bits_per_pixel'].value
shows me (16,16,16), which I presume means 16 bits for each of R, G, B.
Is there any way I can get pgmagick, and all its image manipulation
functions, to work properly with 16-bit images (well, 12-bit, as I said)
like this one?
Perhaps I just need to use a new version of gm or pgmagick?
Or could it be that graphicsmagick is not passing the correct flags to
'dcraw', which it runs externally? No, that's not the problem, because
if I use pgmagick to load the TIFF file created earlier, I still get
8-bits being reported back to me.
Cheers
JP