Tell me why! ain't nothin' but a mistake describing media item differences with media fragments uri and speech synthesis
1. Tell me why! Ain't nothin' but a mistake?
Describing Media Item Differences with Media
Fragments URI and Speech Synthesis
Thomas Steiner (tomac@google.com, @tomayac)
Raphaël Troncy (raphael.troncy@eurecom.fr, @rtroncy)
http://www.ourprg.com/wp-content/uploads/2013/03/wallpapers ru corvuscorax 2560x1440 chelyabinskiy meteor.jpg
2. Introduction
Context of this work:
● Event summarization based on multimedia data shared publicly
on social networks.
● Developed an application that auto-generates media galleries.
3. Media gallery creation steps
1) Extract media items from multiple social networks
[Rizzo2012] G. Rizzo, T. Steiner, R. Troncy, R. Verborgh, J.-L. Redondo García, R. Van de Walle. What
fresh media are you looking for?: retrieving media items from multiple social networks. In Proceedings of the
2012 international workshop on Socially-aware multimedia, pp. 15–20, 2012
4. Media gallery creation steps (cont.)
2) Deduplicate visually similar media items
[Steiner2013_1] Thomas Steiner, Ruben Verborgh, Joaquim Gabarró Vallés, and Rik Van de Walle. Near-
duplicate Photo Deduplication in Event Media Shared on Social Networks. In Proceedings of the
International Conference on Advanced IT, Engineering and Management, 2013
5. Media gallery creation steps (cont.)
3) Rank media item clusters
[Steiner2013_2] Thomas Steiner. A Meteoroid on Steroids: Ranking Media Items Stemming from Multiple
Social Networks. In Companion Publication of the IW3C2 WWW 2013 Conference, May 13–17, 2013, Rio de
Janeiro, Brazil.
6. Media gallery creation steps (cont.)
4) Compile media galleries
[Steiner2012_1] T Steiner, R Verborgh, J Gabarro, R Van de Walle. Defining
aesthetic principles for automatic media gallery layout for visual and audial event
summarization based on social networks. In Quality of Multimedia Experience
(QoMEX), 2012 Fourth International Workshop on, 2012
[Steiner2013_3] Thomas Steiner and Christopher Chedeau. To Crop, Or Not to
Crop: Compiling Online Media Galleries. In Companion Publication of the IW3C2
WWW 2013 Conference, May 13–17, 2013, Rio de Janeiro, Brazil
7. Research Question
"Given a complex algorithm like a media item clustering algorithm, can
we use Media Fragments URIs together with speech synthesis to
describe the algorithm's results rationales?"
● Human raters that evaluate algorithm results are non-experts.
● Can help algorithm developers improve the algorithms.
● Generalization potential for the proof-of-concept.
8. Media Fragments URIs
A media item tile is a spatial media fragment
xywh.js—Polyfill for spatial media fragments
<img src="kitten.jpg#xywh=100,100,50,50"/>
<img src="kitten.jpg#xywh=pixel:100,100,50,50"/>
<img src="kitten.jpg#xywh=percent:25,25,50,50"/>
Available as open source on GitHub:
https://github.com/tomayac/xywh.js
9. Media Fragments URIs (cont.)
Using a tile-wise average-histogram-based media item deduplication
algorithm with face detection.
Makes use of Media Fragments URIs [Troncy2012] to make semantic
statements about fragments of media items:
@base <http://example.org/> .
@prefix ma: <http://www.w3.org/ns/ma-ont> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix db: <http://dbpedia.org/resource/> .
@prefix dbo: <http://dbpedia.org/ontology/> .
@prefix col: <http://purl.org/colors/rgb/> .
<video> a ma:MediaResource .
<video#t=,10&xywh=0,0,30,40> a ma:MediaFragment ;
foaf:depicts db:Face .
<video#t=,10&xywh=0,0,10,10> a ma:MediaFragment ;
dbo:colour col:f00 .
[Troncy2012] R. Troncy, E. Mannens, S. Pfeiffer, D. Van Deursen, M. Hausenblas, P. Jagenstedt, J. Jansen, Y.
Lafon, C. Parker, and T. Steiner, “Media Fragments URI 1.0 (basic),” Recommendation, W3C, 2012
10. Deduplicating media items
Each tile of a media item has its unique URI:
● http://example.org/image.png#xywh=0,0,10,10
We can leverage this fact to make semantic statements about media
item similarity, for example, to debug the deduplication algorithm.
11. Deduplicating media items (cont.)
Algorithm Matching Conditions
Cond. 1: Out of m tiles of a media item with n tiles (m <= n), the
average color of at most tiles_threshold tiles may differ not more
than similarity_threshold from their counterpart tiles.
Cond. 2: The numbers f1 and f2 of detected faces in both media items
have to be the same. We note that the algorithm does not recognize
faces, but only detects them.
Cond. 3: If the average colors of a tile and its counterpart tile are within
the black-and-white tolerance bw_tolerance, these tiles are not
considered and tiles_threshold is decreased accordingly.
12. Deduplicating media items (cont.)
Using a speech synthesizer and speech generation to make spoken
statements based on RDF statements about visual similarity of media
item tiles.
Based on Speak.js (https://github.com/kripken/speak.js)
13. Deduplicating media items (cont.)
Human Rater Decisions
Clustering Consent: Two or more media items are clustered by the
algorithm and the human rater agrees. The human rater wants to
understand why they were clustered.
Clustering Dissent: Two or more media items are clustered by the
algorithm, but the human rater thinks that they should not have been
clustered. The human rater wants to understand why they were
incorrectly clustered.
Non-Clustering Dissent: Two or more media items are not clustered
by the algorithm, but the human rater thinks that they should have
been clustered. The human rater wants to understand why they
were not clustered.
14. Deduplicating media items (cont.)
Low-level debug output
- Similarity threshold: 15 (Cond. 1)
- Tiles threshold: 67 (Cond. 1)
- Similar tiles: 52 (Cond. 1)
- Faces left: 0. Faces right: 0 (Cond. 2)
- BW tolerance: 1 (Cond. 3)
- Not considered tiles: 22 (Cond. 3)
- Effective tiles threshold: 45 (Cond. 3)
Needs to be lifted to normal human language in order to be
understandable by non-domain experts.
15. Natural Speech Generation
Reiter and Dale [Reiter2000] differentiate three phases of speech
generation:
Document planning determines the content and structure of a
document.
Microplanning decides which words, syntactic structures, etc. are used
to communicate the chosen content and structure.
Realization maps the abstract representations used by microplanning
into text.
[Reiter2000] E. Reiter and R. Dale, Building Natural Language Generation Systems,
Studies in Natural Language Processing. Cambridge University Press, 2000.
16. Natural Speech Generation (cont.)
Document Planning: We need to convey the currently selected
tiles_threshold and similarity_threshold, the number of detected faces f1
and f2 in each media item, and the number of tiles not considered given
the bw_tolerance parameter.
Microplanning: We need to decide on a matching condition aspect of
the algorithm that will be first highlighted. Afterwards, we need to
elaborate on secondary matching conditions such as detected faces and
black-and-white tolerance. The grammatical number (plural or singular)
needs to be taken into account. The microplanner needs to decide when
exactness (e.g., “99% of all tiles”) and when approximation of calculated
values (e.g., “roughly 50%”) better suits the human evaluators’ needs.
Realization: We need to map the abstract representations used by the
microplanning step into text.
17. Natural Speech Generation (cont.)
“However, 22 tiles
were not considered, as
they are either too bright or
too dark, which is a
common source of
clustering issues.”