make_slideshow.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# vim: ts=4 et sw=4 sts=4 ai

#
#   Makes slideshow XML files for gnome/mate desktop using a
# parameter list of image files.
#
#   Example usage;
# make_slideshow.py earthporn/* earthporn/slideshow.xml
#


IMAGE_TIME = 300
TRANSITION_TIME = 15
STARTTIME = (2009, 8, 4)
IMAGE_EXTENSIONS = (".bmp", ".gif", ".jpg", ".jpeg", ".png")

import sys
import os
from datetime import datetime
import xml.etree.ElementTree as ET


def starttime(parent, t):
    if isinstance(t, tuple):
        t = apply(datetime, t)
    elm = ET.SubElement(parent, "starttime")
    ET.SubElement(elm, "year").text = "%04d" % t.year
    ET.SubElement(elm, "month").text = "%02d" % t.month
    ET.SubElement(elm, "day").text = "%02d" % t.day
    ET.SubElement(elm, "hour").text = "%02d" % t.hour
    ET.SubElement(elm, "minute").text = "%02d" % t.minute
    ET.SubElement(elm, "second").text = "%02d" % t.second

def static(parent, filename):
    elm = ET.SubElement(parent, "static")
    ET.SubElement(elm, "duration").text = "%.1f" % (IMAGE_TIME - TRANSITION_TIME)
    ET.SubElement(elm, "file").text = os.path.abspath(filename)

def transition(parent, begin_filename, end_filename):
    elm = ET.SubElement(parent, "transition")
    ET.SubElement(elm, "duration").text = "%.1f" % TRANSITION_TIME
    ET.SubElement(elm, "from").text = os.path.abspath(begin_filename)
    ET.SubElement(elm, "to").text = os.path.abspath(end_filename)

if __name__ == '__main__':
    if not sys.argv[1:]:
        sys.exit("No files specified")

    bg_files = sys.argv[1:]
    if bg_files[-1].endswith('.xml'):
        xml_file = bg_files[-1]
        bg_files = bg_files[:-1]
    else:
        while True:
            xml_file = raw_input("Output file [slideshow.xml]: ").strip()
            if not xml_file:
                xml_file = "slideshow.xml"
            if xml_file.endswith(".xml"):
                break

    if not bg_files:
        sys.exit("No background images provided")

    bg_files.sort()

    root = ET.Element("background")
    tree = ET.ElementTree(root)

    starttime(root, STARTTIME)

    is_first = True
    last_bg_file = None
    for bg_file in bg_files[:]:
        if not bg_file.lower()[-4:] in IMAGE_EXTENSIONS:
            bg_files.remove(bg_file)
            continue

        if not is_first:
            transition(root, last_bg_file, bg_file)

        static(root, bg_file)

        is_first = False
        last_bg_file = bg_file

    transition(root, last_bg_file, bg_files[0])

    tree.write(xml_file)