Convert supported files to an RGB image with Wand/ImageMagick

gistfile1.py

import subprocess
from django.core.mail import mail_admins

def convert_to_rgb(local_file):
    """
    Returns an RGB Wand image or one with the original colourspace if the conversion fails.
    Colourspace conversion is currently not working with the Wand API: https://github.com/dahlia/wand/issues/110
    """
    in_filename = '%s[0]' % local_file.name
    out_filename = '%s_rgb.jpg' % local_file.name

    p = subprocess.Popen(['convert',
        '-quality', '90',
        '-density', '200',
        '-colorspace', 'RGB',
        in_filename, out_filename
    ], stdout=subprocess.PIPE, stderr=subprocess.PIPE)

    out, err = p.communicate()

    if err:
        mail_admins("Image conversion error", "%s\n%s" % (local_file.name, err))
        local_file.seek(0)
        return WandImage(file=local_file)
    else:
        return WandImage(file=open(out_filename))