WURFL Test Suite: Testing Video with Alembik
by Dani Alonso (Kimia) and Luca Passani (editor)
Important Note:
Alembik is currently an open-join-venture of two companies: Kimia, from Spain, and Open Reply,
from Italy. Their common goal is to bring the power of free media processing and
web rendering to every developer and company. Please visit the
Alembik web page.
Alembik Tester Application application allows testing of video download, video streaming and
audio download for different mobile devices.
Testers will be able to use the application through a WAP interface.
No prior knowledge of supported formats and parameters for a given device
will be needed in order to test support for a device physicaly in the hands
of the tester.
Application Features
The application is an easy and practical tool for providing
information to WURFL. By using Alembik, developers can discover
device information for themselves and be assured that the information they
discover will ultimately find its way into the WURFL DB for everyone to access.
After each test, users can inspect the logs for their tests.
These logs will be analysed by Kimia personell and, after inspection, video/audio
information will be added to WURFL.
Testers will be able to select formats simply and quickly. By adjusting the parametrs
with which content is served, a decision can be made about which "parameter configuration"
best suits the device under examination at the moment.
The system also provides a module for Kimia administrators to study and adjust
the data before it gets submitted to WURFL in the form a WURFL patch file.
The application offers testers test content in a variety of formats.
Of course, not all formats will play properly (or at all!) on all the devices.
Also, a supported format may not be reproduceable by a given devices
because of the codecs used for the encoding.
Please observe that, currently, the system does not support all mobile
formats. Nevertheless, the most common ones are supported:
VIDEO AUDIO
DOWNLOAD STREAMING DOWNLOAD STREAMING
3gp 3gp mp3 - -
3g2 mp4 amr - -
mp4 - - wma - -
mov - - aac - -
wmv - - - - - -
Alembik, the Media Transcoding Server, is a Java application providing
transcoding services for different media types (image, audio, video, etc).
User Guide
The Alembik Tester Application is available at:
http://video.wurflpro.com/tester/ (please type this into a mobile device)
There two choices a tester will need to make upon entering the application:
- Video vs. Audio
- Download vs. Streaming
 
Note: In the case of Audio, the choice of streaming is not provided (Alembik
does not provide Audio Streaming at the moment.
After selecting the test method, you will see a page containing all the audio/video
parameters which are relevant for the creation of the media file.
The starting values are obtained from WURFL whenever available as a deafult,
but these values (and the actual formats) can be changed (not all possible values
are valid for all formats).
The following link points to the actual content to be streamed/downloaded:
After viewing the content, you can press either the "OK" or "Bad" button to let us
know whether the viewing experience was acceptable or not.
But this is not it. If you scroll down along the same pgae, you can choose to look
at the same content with an increase or decrease of 10% data quality.
The data quality is measured in terms of bit rates parameters.
There are extra possibilities too. The content may be invalid for that device
(in which case we would like you to let us know by pressing on the
'invalid data' button).
By 'invalid', we mean that the mobile device could not play the media file
because of file format.
Please observe that in case the device could not play the file properly because of
the configuration parameters you should mark it as bad (and not as invalid).
There is one final (but very important!) option available on the same page.
You can choose to perform the test with other formats and media parameters
than the one offered by Alembik by default:
Also you have the possibility to do the test with other parameters, no just with Alembik ones. In case you want to do this you have to click the link showed above. There are two options, make the test with other media file parameters or begin the testing process at the first page where you will select between video or audio test again.
  
If you decide to use your own media file characteristics, you will need to select
several parameters which are grouped in several screens (see above).
For video files, the first step is the selection of the video architecture.
The download option and streaming option are the same as far as this part goes.
The second step is the selection of the video and audio codecs for the video architecture
you have selected previously.
Third step is the selection of the bit rates for video and audio.
Finally you must select the number of frames per second of the output video.
For the audio download test, you need to select the audio codec and the audio bit rate.
The bit rate values for video are always seven, i.e. +50%/ -50% of Alembik bit rate value
improvements. The same applies to Audio, albeit the extra values currently supported by
Alembik are also offered as options.
When you have selected all the parameters needed for the transcoding process,
you will presented with a page similar to the one illustrated earlier (voting buttons, and all).
Of course, the media types are the ones selected by you this time.
Administration Guide
The administration module consists in the view and treatment of application logs produced
by testers. This module allows obtaining a CSV and an XML "wurfl_patch.xml" file.
There are three main pages for access the different administration modules,
the first one is for viewing good logs (which means that users has been satisfied with
the transcoded media file ) and obtaining XML and CSV files from them.
The second one allows viewing bad logs (users are not agree with the transcoded media file)
and obtaining only CSV files from them.
The last one is for modifying logs, and authentication is needed. This module is reserved for Kimia admins. In this module, admins can delete and modify log entries.
Of course, admin pages are built to be be accessed with fully-flòedged web browsers.
Good Logs:
URL ' http://video.wurflpro.com/tester/goodlogs.do
This page will show the list of good logs stored on the server.
CSV and XML files for each or all logs can be obtaied here.
Bad Logs:
URL ' http://video.wurflpro.com/tester/badlogs.do
Discussions and Questions
Discussion and questions about the Video Test Suite can ve directed at the
WurflVideo mailing list available at Yahoogroups:
http://tech.groups.yahoo.com/group/wurflvideo/
Enjoy!
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