support png/jpg frames

views.py

@@ -0,0 +1,52 @@
+import os
+import ox
+
+from django.conf import settings
+from django.shortcuts import get_object_or_404
+
+import requests
+
+from oxdjango.http import HttpFileResponse
+from item import models
+from archive import extract
+
+def extract_source_frame(self, position, format):
+    offset = 0
+    streams = self.streams()
+    for stream in streams:
+        if stream.duration + offset < position:
+            offset += stream.duration
+        else:
+            if not stream.file.is_video or not stream.file.info.get('video'):
+                return None
+            position = position - offset
+            path = None
+            if stream.file.data:
+                height = stream.file.info['video'][0]['height']
+                video_path = stream.file.data.path
+                path = os.path.join(settings.MEDIA_ROOT, stream.path(),
+                                    'source-frames', "%dp" % height, "%s.%s" % (position, format))
+                if not os.path.exists(path) and stream.media:
+                    extract.frame(video_path, path, position, height, info=stream.file.info)
+                if not os.path.exists(path):
+                    return None
+            return path
+
+def source_frame(request, id, position=None, format="jpg"):
+    if format not in ("jpg", "png"):
+        format = "jpg"
+    content_type = "image/jpeg" if format == "jpg" else "image/png"
+    item = get_object_or_404(models.Item, public_id=id)
+    if not item.access(request.user):
+        return HttpResponseForbidden()
+    frame = None
+    if not position:
+        position = item.poster_frame
+    else:
+        position = float(position.replace(',', '.'))
+
+    frame = extract_source_frame(item, position, format)
+    response = HttpFileResponse(frame, content_type=content_type)
+    if request.method == 'OPTIONS':
+        response.allow_access()
+    return response