peter berrett <pwberr...@gmail.com> wrote: > I am trying to build a program that can find comets in a series of > astronomical images. I have already written functions to find the comet in a > series of images, the data of which is stored in embedded lists.
> The area I am having difficulty with is take a standard gif file (1024 x > 1024) and reading it into an array or embedded lists. > In a nutshell here is an example of what I want to do > Let's say I have a gif file called 20130428_0000_c2_1024.gif in a folder > called c:\comets > I want to read the data from that gif file taking the red data (excluding > the green and blue data) and store that in an array called Image[][] which > is a nested array length 1024 with a list in each item of 1024 length (ie > 1024 x 1024) > Could someone please provide a piece of code to do the above so I can then > go on to modify it to pick up different files from different folders? In > particular I am keen to seen how you read in the data and also how you > change the directory from which you are reading the image. > the following should do the trick using, as Fábio already suggested, the Python Image Library (PIL): ----------------8<------------------------- #!/ur/bin/env python import Image im = Image.open( 'c:/comets/20130428_0000_c2_1024.gif' ) w, h = im.size red_arr = [ ] for y in range( h ) : red_line = [ ] for x in range( w ) : red_line.append( im.getpixel( ( x, y ) )[ 0 ] ) red_arr.append( red_line ) ----------------8<------------------------- For obvious reasons I couldn't use 'Image' as the name of the list of lists, so it's 'red_arr' instead. This is probably not the fas- test solution, but it's simple and hopefully will get you started. Concerning reading other files: here I may not understand your problem since it looks rather trivial to me by simply passing the open() method of 'Image' the name of a file in a different directory. Regards, Jens -- \ Jens Thoms Toerring ___ j...@toerring.de \__________________________ http://toerring.de -- http://mail.python.org/mailman/listinfo/python-list