[Tutor] Parsing os.popen(command) output

[Bill Burns]

[Bill]
>>Here's the typical output from the command:
>>[start output]
>>TIFF Directory at offset 0x8
>>
>>   Subfile Type: (0 = 0x0)
>>
>>   Image Width: 12000 Image Length: 16800
>>
>>   Resolution: 400, 400 pixels/inch
>>
>>   Bits/Sample: 1
>>
>>   Compression Scheme: CCITT Group 4
>>
>>   Photometric Interpretation: min-is-white
>>
>>   Samples/Pixel: 1
>>
>>   Rows/Strip: 16800
>>
>>   Planar Configuration: single image plane
>>
>>   DocumentName: buzzsaw.com
>>[end output]
>>
>>I need to return the size (width & length) in inches of the Tiff. So I
>>need the information on lines:
>>
>>Image Width: 12000 Image Length: 16800
>>Resolution: 400, 400 pixels/inch
>>
>>Example: 12000 / 400 = 30 & 16800 / 400 = 42, so the Tiff is 30" x 42".
>>

[Kent]
> I would process the data as I find it rather than use all the helper lists. The data format is simple enough that str.split() can be used to extract it. I used float() instead of int() so it will get the correct answer when the dimensions are not whole inches. Something like this:
> 
> def getTiffWidthLength():
>      for line in os.popen(command).readlines():
>          if line.startswith('  Image Width:'):
>             data = line.strip().split()
>             rawWidth = float(data[2])
>             rawLength = float(data[5])
>          elif line.startswith('  Resolution:'):
>             data = line.strip().split()
>             wRes = float(data[1][1:])
>             lRes = float(data[2])
> 
>      width = rawWidth / wRes
>      length = rawLength / lRes
>      print width, length
> 

Kent,

Thank you for the reply! I knew there had to be a different way to do
it, I didn't like the three lists in there either :-)

One thing:
I had to change the line

wRes = float(data[1][1:])

it was returning '00,' (zero, zero, comma) instead of '400', so I
changed it to this:

wRes = float(data[1][:3])

but then I thought, what if I get a tif with a resolution that is <>
than 3 digits?

So I opted for this

wRes = float(data[1].strip(','))

which seems to work fine.

Thanks again!!

Bill