diff --git a/render.py b/render.py
index e62f513..df5c600 100644
--- a/render.py
+++ b/render.py
@@ -15,40 +15,7 @@ import lxml.etree
 
 from .pi import random
 from .render_kdenlive import KDEnliveProject, _CACHE, melt_xml, get_melt
-
-
-def random_int(seq, length):
-    n = n_ = length - 1
-    #print('len', n)
-    if n == 0:
-        return n
-    r = seq() / 9 * 10
-    base = 10
-    while n > 10:
-        n /= 10
-        r += seq() / 9 * 10
-        base += 10
-    r = int(round(n_ * r / base))
-    return r
-
-def random_choice(seq, items, pop=False):
-    n = random_int(seq, len(items))
-    if pop:
-        return items.pop(n)
-    return items[n]
-
-def chance(seq, chance):
-    return (seq() / 10) < chance
-
-def get_clip_by_seqid(clips, seqid):
-    selected = None
-    for i, clip in enumerate(clips):
-        if clip['seqid'] == seqid:
-            selected = i
-            break
-    if selected is not None:
-        return clips.pop(i)
-    return None
+from .render_utils import *
 
 
 def write_if_new(path, data, mode=''):
@@ -342,35 +309,6 @@ def compose(clips, target=150, base=1024, voice_over=None, options=None):
         print(scene['audio-center']['A1'][-1])
     return scene, used
 
-def get_track_duration(scene, k, n):
-    duration = 0
-    for key, value in scene.items():
-        if key == k:
-            for name, clips in value.items():
-                if name == n:
-                    for clip in clips:
-                        duration += int(clip['duration'] * 24)
-                    return duration / 24
-
-def get_scene_duration(scene):
-    if isinstance(scene, str):
-        with open(scene) as fd:
-            scene = json.load(fd)
-    duration = 0
-    for key, value in scene.items():
-        for name, clips in value.items():
-            for clip in clips:
-                duration += int(clip['duration'] * 24)
-            return duration / 24
-
-def get_offset_duration(prefix):
-    duration = 0
-    for root, folders, files in os.walk(prefix):
-        for f in files:
-            if f == 'scene.json':
-                duration += get_scene_duration(scene)
-    return duration
-
 def write_subtitles(data, folder, options):
     data = fix_overlaps(data)
     path = folder / "front.srt"
@@ -439,12 +377,6 @@ def render(root, scene, prefix='', options=None):
         files.append(path)
     return files
 
-def get_project_duration(file):
-    out = melt_xml(file)
-    chain = lxml.etree.fromstring(out).xpath('producer')[0]
-    duration = int(chain.attrib['out']) + 1
-    return duration
-
 def get_fragments(clips, voice_over, prefix):
     import itemlist.models
     import item.models
@@ -496,19 +428,6 @@ def get_fragments(clips, voice_over, prefix):
     fragments.sort(key=lambda f: ox.sort_string(f['name']))
     return fragments
 
-def parse_lang(lang):
-    if lang and "," in lang:
-        lang = lang.split(',')
-    if isinstance(lang, list):
-        tlang = lang[1:]
-        lang = lang[0]
-    else:
-        tlang = None
-    if lang == "en":
-        lang = None
-    return lang, tlang
-
-
 def render_all(options):
     options = load_defaults(options)
     prefix = options['prefix']
@@ -861,23 +780,6 @@ def get_srt(sub, offset, lang, tlang):
         sdata["out"] += offset
     return sdata
 
-def fix_overlaps(data):
-    previous = None
-    for sub in data:
-        if previous is None:
-            previous = sub
-        else:
-            if sub['in'] < previous['out']:
-                previous['out'] = sub['in'] - 0.001
-            previous = sub
-    return data
-
-def shift_clips(data, offset):
-    for clip in data:
-        clip['in'] += offset
-        clip['out'] += offset
-    return data
-
 def scene_subtitles(scene, options):
     import item.models
     offset = 0
@@ -939,57 +841,6 @@ def update_subtitles(options):
         subs = scene_subtitles(scene, options)
         write_subtitles(subs, folder, options)
 
-def ass_encode(subs, options):
-    if "lang" in options:
-        langs = options["lang"].split(',')
-    else:
-        langs = list(subs[0]["values"])
-    #print('ass_encode', langs, options)
-    #print(subs)
-
-    header = '''[Script Info]
-ScriptType: v4.00+
-PlayResX: 1920
-PlayResY: 1080
-ScaledBorderAndShadow: yes
-YCbCr Matrix: None
-
-[V4+ Styles]
-Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
-'''
-    ass = header
-    offset = options.get("sub_margin", 10)
-    spacing = options.get("sub_spacing", 20)
-    height = 42
-    styles = []
-    for lang in reversed(langs):
-        if isinstance(options.get("font"), list) and lang in options["font"]:
-            font = options["font"][lang]
-        else:
-            font = 'SimHei' if lang in ('zh', 'jp') else 'Menlo'
-        if isinstance(options.get("font_size"), list) and lang in options["font_size"]:
-            size = options["font_size"][lang]
-        else:
-            size = 46 if font == 'SimHei' else 42
-
-        styles.append(
-            f'Style: {lang},{font},{size},&Hffffff,&Hffffff,&H0,&H0,0,0,0,0,100,100,0,0,1,1,0,2,10,10,{offset},1'
-        )
-        offset += size + spacing
-    ass += '\n'.join(reversed(styles)) + '\n'
-    events = [
-        'Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text'
-    ]
-    for sub in subs:
-        start = ox.format_timecode(sub['in']).rstrip('0')
-        stop = ox.format_timecode(sub['out']).rstrip('0')
-        for lang in reversed(langs):
-            value = sub['values'][lang]
-            event = f'Dialogue: 0,{start},{stop},{lang},,0,0,0,,{value}'
-            events.append(event)
-    ass += '\n\n[Events]\n' + '\n'.join(events) + '\n'
-    return ass
-
 def update_m3u(render_prefix, exclude=[]):
     files = ox.sorted_strings(glob(render_prefix + "*/*/back.mp4"))
     for ex in exclude:
diff --git a/render_utils.py b/render_utils.py
new file mode 100644
index 0000000..ed3d2c6
--- /dev/null
+++ b/render_utils.py
@@ -0,0 +1,154 @@
+import re
+import os
+
+import lxml.etree
+
+from .render_kdenlive import melt_xml
+
+def parse_lang(lang):
+    if lang and "," in lang:
+        lang = lang.split(',')
+    if isinstance(lang, list):
+        tlang = lang[1:]
+        lang = lang[0]
+    else:
+        tlang = None
+    if lang == "en":
+        lang = None
+    return lang, tlang
+
+def random_int(seq, length):
+    n = n_ = length - 1
+    #print('len', n)
+    if n == 0:
+        return n
+    r = seq() / 9 * 10
+    base = 10
+    while n > 10:
+        n /= 10
+        r += seq() / 9 * 10
+        base += 10
+    r = int(round(n_ * r / base))
+    return r
+
+def random_choice(seq, items, pop=False):
+    n = random_int(seq, len(items))
+    if pop:
+        return items.pop(n)
+    return items[n]
+
+def chance(seq, chance):
+    return (seq() / 10) < chance
+
+def get_clip_by_seqid(clips, seqid):
+    selected = None
+    for i, clip in enumerate(clips):
+        if clip['seqid'] == seqid:
+            selected = i
+            break
+    if selected is not None:
+        return clips.pop(i)
+    return None
+
+def get_scene_duration(scene):
+    if isinstance(scene, str):
+        with open(scene) as fd:
+            scene = json.load(fd)
+    duration = 0
+    for key, value in scene.items():
+        for name, clips in value.items():
+            for clip in clips:
+                duration += int(clip['duration'] * 24)
+            return duration / 24
+
+def get_offset_duration(prefix):
+    duration = 0
+    for root, folders, files in os.walk(prefix):
+        for f in files:
+            if f == 'scene.json':
+                duration += get_scene_duration(scene)
+    return duration
+
+def get_track_duration(scene, k, n):
+    duration = 0
+    for key, value in scene.items():
+        if key == k:
+            for name, clips in value.items():
+                if name == n:
+                    for clip in clips:
+                        duration += int(clip['duration'] * 24)
+                    return duration / 24
+
+def get_project_duration(file):
+    out = melt_xml(file)
+    chain = lxml.etree.fromstring(out).xpath('producer')[0]
+    duration = int(chain.attrib['out']) + 1
+    return duration
+
+def fix_overlaps(data):
+    previous = None
+    for sub in data:
+        if previous is None:
+            previous = sub
+        else:
+            if sub['in'] < previous['out']:
+                previous['out'] = sub['in'] - 0.001
+            previous = sub
+    return data
+
+def shift_clips(data, offset):
+    for clip in data:
+        clip['in'] += offset
+        clip['out'] += offset
+    return data
+
+def ass_encode(subs, options):
+    if "lang" in options:
+        langs = options["lang"].split(',')
+    else:
+        langs = list(subs[0]["values"])
+    #print('ass_encode', langs, options)
+    #print(subs)
+
+    header = '''[Script Info]
+ScriptType: v4.00+
+PlayResX: 1920
+PlayResY: 1080
+ScaledBorderAndShadow: yes
+YCbCr Matrix: None
+
+[V4+ Styles]
+Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
+'''
+    ass = header
+    offset = options.get("sub_margin", 10)
+    spacing = options.get("sub_spacing", 20)
+    height = 42
+    styles = []
+    for lang in reversed(langs):
+        if isinstance(options.get("font"), list) and lang in options["font"]:
+            font = options["font"][lang]
+        else:
+            font = 'SimHei' if lang in ('zh', 'jp') else 'Menlo'
+        if isinstance(options.get("font_size"), list) and lang in options["font_size"]:
+            size = options["font_size"][lang]
+        else:
+            size = 46 if font == 'SimHei' else 42
+
+        styles.append(
+            f'Style: {lang},{font},{size},&Hffffff,&Hffffff,&H0,&H0,0,0,0,0,100,100,0,0,1,1,0,2,10,10,{offset},1'
+        )
+        offset += size + spacing
+    ass += '\n'.join(reversed(styles)) + '\n'
+    events = [
+        'Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text'
+    ]
+    for sub in subs:
+        start = ox.format_timecode(sub['in']).rstrip('0')
+        stop = ox.format_timecode(sub['out']).rstrip('0')
+        for lang in reversed(langs):
+            value = sub['values'][lang]
+            event = f'Dialogue: 0,{start},{stop},{lang},,0,0,0,,{value}'
+            events.append(event)
+    ass += '\n\n[Events]\n' + '\n'.join(events) + '\n'
+    return ass