--- a/src/pyams_media/interfaces/__init__.py	Mon Feb 18 16:12:44 2019 +0100
+++ b/src/pyams_media/interfaces/__init__.py	Mon Sep 28 15:24:32 2020 +0200
@@ -105,6 +105,9 @@
     def has_conversion(self, formats):
         """Check if one of given formats is available in conversions"""
 
+    def get_sources(self, request):
+        """Get media sources in JSON format"""
+
 
 class IMediaConversion(Interface):
     """Marker interface for already converted media files"""

--- a/src/pyams_media/media.py	Mon Feb 18 16:12:44 2019 +0100
+++ b/src/pyams_media/media.py	Mon Sep 28 15:24:32 2020 +0200
@@ -12,7 +12,9 @@
 
 __docformat__ = 'restructuredtext'
 
+import json
 import re
+from collections import OrderedDict
 from mimetypes import guess_extension, guess_type
 
 from pyramid.events import subscriber
@@ -27,12 +29,18 @@
 from pyams_file.interfaces import IFile
 from pyams_media.ffbase import FFmpeg
 from pyams_media.ffdocument import FFDocument
-from pyams_media.interfaces import CUSTOM_AUDIO_TYPES, CUSTOM_VIDEO_TYPES, IMediaConversion, IMediaConversionUtility, \
-    IMediaConversions, IMediaInfo, MEDIA_CONVERSIONS_KEY, VIDEO_FRAME_SIZE
-from pyams_utils.adapter import ContextAdapter, ContextRequestViewAdapter, adapter_config, get_annotation_adapter
+from pyams_media.interfaces import CUSTOM_AUDIO_TYPES, CUSTOM_VIDEO_TYPES, IMediaConversion, \
+    IMediaConversionUtility, IMediaConversions, IMediaInfo, MEDIA_CONVERSIONS_KEY, \
+    VIDEO_FRAME_SIZE
+from pyams_media.video import get_video_type
+from pyams_utils.adapter import ContextAdapter, ContextRequestViewAdapter, adapter_config, \
+    get_annotation_adapter
+from pyams_utils.date import get_timestamp
 from pyams_utils.factory import factory_config
 from pyams_utils.interfaces.tales import ITALESExtension
 from pyams_utils.registry import get_global_registry, query_utility
+from pyams_utils.url import absolute_url
+
 
 #
 # Media infos
@@ -80,10 +88,10 @@
         content_type = target.content_type
         if isinstance(content_type, bytes):
             content_type = content_type.decode()
-        target_name = '{name}{width}.{extension}'.format(name=content_type.split('/', 1)[0]
-                                                             if content_type else 'media',
-                                                         width='-{0}'.format(width) if width else '',
-                                                         extension=extension)
+        target_name = '{name}{width}.{extension}'.format(
+            name=content_type.split('/', 1)[0] if content_type else 'media',
+            width='-{0}'.format(width) if width else '',
+            extension=extension)
         if target_name in self:
             del self[target_name]
         target.filename = target_name
@@ -113,6 +121,24 @@
                 return True
         return False
 
+    def get_sources(self, request):
+        sources = []
+        types_order = ('video/mp4','video/webm','video/ogg','video/x-flv')
+        media_width = 0
+        previous_type = None
+        for conversion in self.get_conversions(order=types_order):
+            video_type = get_video_type(conversion, request.registry)
+            min_width = ((media_width or 0) + 1) if (video_type == previous_type) else 0
+            media_width = self.get_conversion_width(conversion.__name__)
+            media_src = '{0}?_={1}'.format(absolute_url(conversion, request),
+                                           get_timestamp(conversion))
+            sources.append({'type': video_type,
+                            'min': min_width,
+                            'max': media_width,
+                            'src': media_src})
+            previous_type = video_type
+        return json.dumps(sources)
+
 
 @adapter_config(context=IFile, provides=IMediaConversions)
 def media_conversions_factory(context):
@@ -129,7 +155,9 @@
         return IMediaConversions(self.context)
 
 
-@adapter_config(name='conversions', context=(Interface, Interface, Interface), provides=ITALESExtension)
+@adapter_config(name='conversions',
+                context=(Interface, Interface, Interface),
+                provides=ITALESExtension)
 class ConversionsExtension(ContextRequestViewAdapter):
     """extension:conversions(media) TALES extension"""