Showing posts with label multimedia. Show all posts
Showing posts with label multimedia. Show all posts

Wednesday, February 8, 2017

Bytes and pixels meet the challenges of human media interpretation

Back in June, I gave a talk at the  Communication Science Department here at Radboud University Nijmegen. Today, I presented a version of that talk to my colleagues in the Language and Speech Technology Research Meeting. The abstract is below together with the slides, which are on SlideShare. During the discussion it became clear that many problems in natural language processing and information retrieval face the issue of human interpretations. It is important to find ways to move forward, although it may not be possible to pack our challenges into neat classification or ranking problems with a single set of consensus ground truth labels. A way forward, is to look to other disciplines for theory of how people understand and use media, and let these inform what we design our systems to do and the ways that we measure success.

Within computer science, "Multimedia" is a field of research that investigates how computers can support people in communication, information finding, and knowledge/opinion building. Multimedia content is defined broadly. It includes not only video, but also images accompanied by text and other information (for example, a geo-location). It can be professionally produced, or generated by users for online sharing. Computer scientists historically have a “love-hate” relationship with multimedia. They “love” it because of the richness of the data sources and the wealth of available data, which leads to interesting problems to tackle with machine learning. They “hate” it because multimedia is a diffuse and moving target: the interpretation of multimedia differs from person to person, and changes over time in the course of its use as a communication medium. This talk gives a view onto ongoing research in the area of multimedia information retrieval algorithms, which help people find multimedia. We look at a series of topics that reveal how pattern recognition, text processing, and crowdsourcing tools are used in multimedia research, and discuss both their limitations and their potential.


Saturday, January 28, 2017

Women's March on Washington: Across time and dimensions in space



It's been one week since the Women's March on Washington (WMW). I was curious to see what would still grip me most strongly now after one week. Filtering through so many topics, so many impressions, so much emotion, what remains with me most clearly is: people's voices.

People are speaking up, speaking out, and, for the first time that I can remember, speaking with unanimous confidence that speaking can and does indeed bring about change. The most obvious case is the power of every citizen to call their government representatives in order to communicate their opinion. But speaking also has the power to open people's minds to fundamentally different perspectives: speaking with each other can lead to the understanding that the world is a single, immense interconnected system. There is and can be no difference between standing up for ourselves and standing up for other people. This understanding builds confidence, lends authority to our individual voices, and allows us to comprehend our own potential at our cores: what we can make happen by all pulling in a common direction is more that we have previously dared to hope or imagine.

This blog post contains observations about the WMW seen through the lens of information, which is my field of research. Specifically, I focus on information as it is captured and shared in multimedia: audio, video, and images.

In Ch. 2 of their Multimedia Computing book, Friedland and Jain discuss communication-related inventions over the course of civilization. Their discussion makes the point is that the era we live in is an era of media recordings, digital media, and the Internet. These inventions provide us with three invariances, which offer historically unique opportunities for communication: invariance of time, invariance of space, and invariance of addressee.

"Invariance" in this case refers to the stability of communication—if a message is invariant, it is not subject to loss or decay. Specifically, these three invariances mean that a message communicated in the past is also available in the future, that a message presented at one place, can be also presented at another, and that a message communicated to one person can be communicated to anyone.

How do these invariances make marching in today's times different than ever before? When our grandparents' generation made signs and took to the street, their message would only reach the people who were present on that street and in that moment. Anything beyond that was dependent on newspaper and radio coverage.

In 2017, the WMW took place in full realization that the march was not limited to that moment, to that space, or to the specific people who were physically in Washington DC. Most of the intended addressees of the march were somewhere completely different. In the case of all three invariances, I observed behavior that reflected the consciousness of people of these information invariances and the need to use them.

Invariance of time: Signs as photo opportunities
Cameras, both conventional and on mobile phones, were everywhere at the WMW. I watched amazed as people took pictures of each holding their signs. Slowly, at the march, it dawned on me that my idea of not bringing a camera to a demonstration outdated. It became apparent to me that people made their signs with the intention of having other people take pictures of them. Some people who had particularly interesting or novel signs were standing at the side of the street. Apparently their purpose standing there was so that people would come up and chat and then pose with the sign for pictures.

A consciousness pervaded the march: a sign is not merely a physical object, but rather a message broadcasted outward without a predetermined limit. Your face on a picture next to a sign anchors it to you as a person in a way that comments on the Web fail to be anchored. The march came together around unity principles. Motivated by these principles, a "selfie" taken with a march sign becomes an "unselfie": an act of selflessness in support of rights and of people without the opportunity to stand up for their own rights.

Invariance of space: Everywhere at once
There was a feeling of connection at the WMW to people who would have liked to have been there, but who weren't able to make the trip to Washington DC. I saw at least one marcher who had listed the names of the people who supported her on her sign. While marching, I felt strongly connected to the people in our circle of family and friends who had stayed at home and watched the media coverage and/or attended other marches.

During the WMW, the mobile phone network clearly suffered overload. Through much of the duration of the march, it was not possible to access the Web via the mobile phone network, to call, or even to send or receive a text. For this reason, we realized that it was that the people who were not at the march were actually understanding what was going on more than the marchers could, although we were actually at the march. The feeling that being the the middle of the march was not necessarily the best way of getting an overall understanding of what was going on enhanced the impression that the march was not happening in a particular physical space, but in fact everywhere at once.

It was only later that evening that I came to fully understand that there had been marches of magnitude in so many places around the the US and the world. Today, it's a week later and I spent some time browsing march pictures on Flickr. March pictures are all simply march pictures, and whether they were taken at the WMW or at a sister march has since faded into the background.

Invariance of addressee: No one missed out on anything
My experience of the march was people, people, and more people. I know Washington DC well, but at times, I felt completely out of sight of anything familiar. During the time that the speakers were speaking we saw no stage: we just had faith that some where in the core of the masses the speakers were speaking on schedule. At one point, someone close to me in crowd said, "Madonna's here!" People seemed excited to hear that, but everyone had realized by then, that it was counterproductive to try to get to the stage.

There was a consciousness that no one was missing out on anything. Not being able to see any of the speakers was not a disappointment, we could all just shrug "Oh, well, I'll catch the speeches on YouTube later". (I spend some time doing that today.) Thinking about what it was like in the middle of the march: I've never experienced a moment, with such a clear sense of shared awareness that that moment would be lived and relived afterwards. For those with similar scifi habits, I'll say, it's the closest I've ever come to experience the feeling of travel across time and relative dimensions in space TARDIS.

Past, present, and future
The weeks leading down to the WMW were already filled with an appreciation of what past marchers had to teach us, and my thoughts frequently turned to the 1963 March on Washington for Jobs and Freedom. Awareness of the contributions of those in whose footsteps we follow is perhaps the most dramatic impact of information communicated across time (54 years ago), space (around the world), and audience (I was not even born then).

I never thought too much about 1963 as a child, but I also never thought too much about fire drills. When the alarm goes off, you calmly and peacefully leave the school. When things become unbearable, you calmly and peacefully go to march in Washington. These are the procedures and the practices that keep us—all of us—safe and keep our efforts to build a just society moving forward. Images, audio recordings, and videos hold the practice before our mind's eye: yes, it does happen, it has happened, and since it needs to happen, it will happen again.

Saturday, June 18, 2016

Multimedia analysis out of the box: new applications and domains

Flickr: Tom Magliery
This blogpost summarizes the panel on the third day of the 14th International Workshop on Content-based Multimedia Indexing CBMI 2016. It includes both statements by the panelists and comments coming from the audience. I was the panel moderator, and was also taking notes as people were speaking (any error in reproducing what people said here is strictly my own).

The panel was structured into three rounds roughly related to the past, present, and future of multimedia analysis research. Each round had an “opener” that the panelists were asked to respond to, and then continued in free form, with the audience also contributing.

First round: The panelists were asked to discuss, “A past vision (that you have had during the last 20 years) for a multimedia analysis application that came to be.”

The early work of GroupLens started a user revolution. It was great to have recommender systems break onto the scene. Their introduction shifted the focus of the community of researchers, also those studying information/multimedia access, from pure computation to involving users. This shift was possible because computers could collect user interactions, providing researchers with large sets of interactions to work with. Recommender systems introduced the key idea that users can benefit from other users, and this idea has come into its own.

Historically, multimedia indexing started with spoken content indexing. (This statement carried the “footnote” that the panelists and the panel moderator all have a speech background.) In the past years, we have seen the maturation of speech and language technology. Now we are on the brink of systems that index all spoken information in multimedia. (But let’s keep breathing in the meantime.)

The panel noticed that it is easier to name past visions that still have not completely come to be. Examples were:

First person video: In the late 1990’s, video life logging started. The goal was to summarize daily life, and to aid memory and remembering. Privacy is a real stumbling block for this vision. However, now we are seeing first person cameras like GoPro: so, perhaps it is video life logging is here, but it is not exactly what we thought it was going to be.

Users: Ten years ago we were developing algorithms for applications, but there was a sense that they would never be put to use. The field of multimedia analysis is now more user centered, although not yet complete so: we are on our way. Sometimes it’s not gaining 5% MAP that makes product usable. Instead, we need to think about different lines.

Education: The panel was in agreement that we have yet to see multimedia reach its potential as a tool for education. This could and should be the century of education!

In the early 1990’s multimedia retrieval and spoken content retrieval were intended to support education. Today, we see that eduction is still mainly about books. MOOCs and online learning resources are growing in popularity, but we are still waiting for multimedia indexing to really contribute to education at large scales.

We used to have the vision that kids should be able to play with information and to communicate with each other as part of studying and learning: These types of applications were fun. What happened to this kind of work? It is a shame that this hasn’t really been put to mainstream use: Is this the responsibility of the multimedia people?

Well, yes. We are all teachers in a way: Why don’t we eat our own dogfood? Looking at this conference, our presentations are all text-heavy sets of PowerPoint slides!

Why is willingness of teachers and journalists to use multimedia tools so low? Do we need to wait until everyone in the world becomes tech friendly to have our research put to use?

Maybe we just don’t have the tools necessary to allow multimedia indexing to come into its own in support of education. We need the tools in order to engage teachers.

We don’t have the time to do education related research. You can’t just do a 10 minute experiment with data from 30 people: people are complex kids are complex! We haven’t been willing to take the time to work with teachers: we haven’t had funding for a 5-10 year sustained effort in this area. But it’s a worthwhile goal.

We need to understand the nature of education. There is a relationship between student and teacher: it is a human relationship. A machine might not be able to motivate the student.

This observation about student behavior stands in contrast to the success of video games in motivating kids. Games appear to motivate kids more so than their parents are able to do. However, today’s games are too simplistic to be an education tool. They don’t reflect real breath.

Final note of the first round: It seems that multimedia analysis researchers don’t talk about “killer applications” anymore. The way we see our success is more diffuse, and maybe that is also OK.

Second round. Panel members were asked to discuss “A current (widely-held) vision for a multimedia analysis application that is doomed.”

Our panelists jumped on the opportunity to be controversial.

Is lifelogging doomed?
Multimedia researchers of course love the huge amounts of data that life logging delivers. But do people really want their lives to be logged? Why would I want all of those picture? Are we just recording without a real application?

When we are healthy and in good shape we have perhaps no reason to record our lives. But when we become older or are in a situation that we need to be managing an illness, things change. In this case, the lifelogging applications are tremendously interesting. For elderly people living alone, it can be a real help: although it does not replace human company.

Why don’t we see this technology being widely used? The problem is not the market. The problem is that we are not marketing or business people: we need someone else to put this technology on the market. This process for doing so is a mess! We develop nice applications, but we need to move on, and the business development never gets done.

Is virtual reality doomed?
We are not in a virtual space having a virtual conference. We are here. Virtual meeting rooms have not come to be and video conferencing fatigue is real. Virtual reality works great in games. Perhaps also in demonstrating things. But in general, augmented reality appears to be the more promising path.

Is multimedia analysis of broadcast television doomed? 
Analysis of news, sports, movies, in fact, any produced content is over. If someone can produce the content, they can also dedicate the effort to annotate it.

A less extreme version of that position is probably, however, more appropriate. When we carry out multimedia research, often produced content is the only content we have. Not every content producer has the resources to create annotations. Finally (as note by the moderator) some types of annotations are against the business interests of people producing multimedia content: Do film producers really want audiences to have a fine-grained breakdown of the violence in film?

The panel agreed that analysis of produced content is very important for knowledge extraction and summaries of large, heterogenous collections. You can extract knowledge and facts: for example, the present needs a 20 minute summary.

Professionals, or specific applications often need detailed summaries: There would be value in summarizing to study for example the soccer moves of a certain player for practice or for strategy purposes.

Personal content often needs summarization: parents like highlights of school games or performances that feature their own children.

Are standards doomed? 
Standards make sense for compression and communication, but standards have been over pushed. Many researchers identify with this situation: You barely know what you’re doing and you make a standard for it. However, the activity that takes place around the production of standards gives rise to new ideas. The fact that descriptors were encoded in MPEG7 gave rise to a lot of further work on descriptors.

Perhaps a more direct way of achieving the same effects is via reference implementations and toolkits. OpenCV is effectively, although not formally, a standard. This kinds of efforts are very important.

Third round: Panel members were asked for “A future vision for a multimedia analysis application that we should strive for.”

The opening comment was interesting and unexpected: As a early-career researcher in multimedia one is drawn to problems that one likes, and that attract and holds one’s attention. However, as a late-career researcher, one looks back and starts to regret not having considered the contribution that one’s career was making to society.

Multimedia for medicine: Young multimedia researchers should consider “joining the doctors”: the field of medecine needs us.

Human rights: Another area with enormous potential social impact is multimedia for human rights. We need algorithms that will allow us to find evidence of violations: examples are the analysis of areal photos to search for hidden destruction and the reconstruction of events using social media.

We need (footnote by moderator) technology that is able to verify the extent to which multimedia reflects the reality that it claims to capture: and, in particular, identify multimedia created with the intent to deceive.

Low quality content is key: Interestingly, some of the most highly socially relevant applications for multimedia involve processing some of the worst images. Multimedia researchers need to be brave enough to venture into areas where content is poor quality, difficult to obtain, and (footnote by moderator) where evaluation of success is highly challenging.

User intent: Multimedia information retrieval has recently experienced the “intent revolution”: the change from focusing on the nature of the items that users are trying to find, to the tasks that users are trying to achieve. Supporting people in their daily lives is not is as obviously socially relevant as education, medical or human rights applications. However, it has an important contribution to make.

Affective computing: We look forward to multimedia systems that support us in the emotional aspects of communicating with multimedia: sharing and mutual remembering. Humans are social creatures (isolations causes us to suffer). Shared experiences allow us to build relationships, share values, and keep the connections needed for social and psychological well-being. Regretfully, current research on affect and sentiment simplifies the emotional aspects of multimedia to the extent that it may be “trivial”. We need to work towards understanding both multimedia and the mind: a key question is: What pieces need to come together in order for someone to experience the reproduction of a memory or an experience?

Hardware and energy consumption: We should not forget that multimedia analysis is possible because of the devices that capture, store and process multimedia. We are ever dependent on hardware. Processing of multimedia costs energy: and future work should also keep energy efficiency in mind.

Closing comments:
When we study multimedia, we study communicating with multimedia. Moving forward it is important to keep the human in human communication.

Is there an end to multimedia? Can we foresee that it might be replaced by something completely different?

We see multimedia as an “everlasting field” encompassing applications that have not yet been invented. However, we should continue to call it “multimedia”, because continuity of what we call it will allow us to build on the past.

Currently, we see more and more other communities doing multimedia: examples are the computer vision community and the speech and language processing community. Having a distinct identity will allow the other fields to avoid reinventing the wheel.

We saw during the first round of the panel that looking back over the past 20 years, we did not do so well in formulating predictions which came true: the technologies that we anticipated have not achieved mainstream uptake (with a few notable exceptions). It’s not dramatic to be wrong in our predictions. However: it is important that we learn from our mistakes.

In general, we do not expect all early-career multimedia researchers to connect to socially relevant applications by “joining the doctors”. But it is good to have a larger vision. When you are writing a paper, embed your ideas within an overall picture of their potential. Embrace the larger meaning of your work and imbue multimedia research with sense of mission.

A big thank you to our panelists and to the members of the audience who contributed to the discussion.

Panelists:
Guillaume Gravier, IRISA, France
Alexander Hauptmann, Carnegie Mellon University, USA
Bernard Merialdo, EURECOM, France

Audience contributors:
Jenny Benois Pineau, University of Bordeaux, France
Bogdan Ionescu, University Politehnica of Bucharest, Romania
Georges Quénot, LIG, France
Stéphane Marchand Maillet, University of Geneva, Switzerland
Mathias Lux, Klagenfurt University, Austria

Sunday, October 27, 2013

Power behind MediaEval: Reflecting on 2013

Power behind MediaEval 2013
The MediaEval 2013 Workshop was held in the Barri Gòtic, the Gothic Quarter, of Barcleona on 18-19 October, just before ACM Multimedia 2013 (held in Barcelona). The workshop was attended by 100 participants, who presented and discussed the results that they had a achieved on 11 tasks, 6 main tasks, and on 5 "Brave New Tasks" that ran for the first time this year.

The workshop produced a working notes proceedings containing 96 short working papers, and has been published by CEUR-WS.org.

The purpose of MediaEval is to offer tasks to the multimedia community that  support research progress on multimedia challenges that have a social or a human aspect. The tasks are autonomous and each run by a different team of task organizers. My role within MediaEval is to guide the process of running tasks, which involves providing feedback to task organizers and sending out the cues that keep the tasks ruining smoothly and on time. Today I did a quick count that revealed that during the 2013 season, I wrote 1529 personal emails to people that contained the keyword "MediaEval" in them.

What makes MediaEval work, however, cannot be expressed in numbers. Rather, it is the dedication and intensive effort of a large group of people, who propose and organize tasks and carry out the logistics that make the workshop come together. My motivation to continue MediaEval year after year stems largely from an underlying sense of awe at what these people do: both at the work that I am aware of and also at the many things that they do behind the scenes that make largely invisible. These people are the power behind MediaEval. Here I represent them with the picture above, which are the power plugs arranged by Xavi Anguera from Telefonica with the assistive effort of Bart Thomee from Yahoo! Research. The process involved a combination of precision car driving and applied electrical engineering.

In the airplane back from Barcelona yesterday, I finished processing the responses that we received from the participant surveys (collected during the workshop), input from the organizers meeting (held on Sunday after the workshop), and feedback that people gave me verbally during ACM Multimedia (last week). These points are summarized below.

Thus endeth MediaEval 2013, but at the same time beginneth the season of MediaEval 2014. Hope to have you aboard.

Community Feedback from the MediaEval 2013 Multimedia Benchmarking Season + Workshop

The most important feedback point this year was the new structure of the workshop, which was very well received. This year the workshop was faster paced and we introduced poster sessions. We were happy that people liked the short talks and that the poster sessions were considered to be useful and productive. There is a clear trend to preferring there to be more discussion time at the workshop, both in the presentation sessions and in the poster sessions. An idea for the future is to separate passive poster time (posters are hanging and people can look at them but the presenter need not be present) from active poster time (presenter is standing at the poster).

The number one most frequent request was for MediaEval to provide more detailed information. This request was made with respect to a range of areas: descriptions of the tasks should always strive to be maximally explicit; descriptions of the evaluation methods should be detailed and available in a timely manner; task overview talks at the workshop should contain examples and descriptions that allow a general audience (i.e., people who did not participate in the task) to understand the task easily.

Other suggestions were to increase consistency check and continue to promote industry involvement. Finally, requests for more time for preparation of presentations and to explicitly invite (and support) groups to make demos with the posters.

The organizers meeting on Sunday was the source of additional feedback. Task organization requires a huge amount of time and dedication from task organization teams and it is important that this is distributed as evenly as possible across the year and across people. In general, tasks would benefit from additional practical guidance on organization. This includes task management and evaluation methodologies. Since MediaEval is a decentralized system, the source of this guidance must be people with past experience with task organization and communication between tasks. Here, the bi-weekly telcos for organizers are an important tool.

In the coming year, the awards and sponsorship committee can expect an expanded role. The outreach to early-career researchers and to researchers located outside of Europe (in the form of travel grants) is seen by the organizers to be not merely a "nice-to-have", but rather a central part of MediaEval's mission. There is solid consensus about the usefulness of the MediaEval Distinctive Mentions (MDMs). MDMs are peer-to-peer certificates awarded by task organizers to each other or to the participants of their tasks. The MDMs  allow the community to send public messages between members of the community, and especially to point out participant submissions that are highly innovative or have particularly high potential (although they may not have been top scorers according to the official evaluation metric). It is important to make clear that the MediaEval Distinctive Mention is not an "award", since the process by which they are chosen is intentionally kept very informal. In the coming year, we will be investigating the issue of whether MediaEval should introduce a five-year impact award, that would be more formal in nature. The peer-to-peer MDMs will be maintained, although and effort will be made to make them increasingly transparent.

In general we were satisfied with the process used to produce the proceedings. Having groups do an online check of their metadata was helpful. If future years also involve proceedings with 50+ papers, we will need to further streamline the schedule for submission---with the ultimate goal of having the proceedings online at the moment that the workshop opens.

Tuesday, October 22, 2013

CrowdMM 2013: Crowdsourcing in Mutlimedia Emerged or Emerging?

CrowdMM 2013, the 2nd International ACM Workshop on Crowdsourcing for Multimedia, was held in conjunction with ACM Multimedia 2013 on 22 October 2013. This workshop is the second edition of the CrowdMM series, which I have previously written about here. This year it was organized by Wei-Ta Chu (National Chung Cheng University in Taiwan) and Kuan-Ta Chen (Academia Sinica in Taiwan) and myself, with critical support from Tobias Hossfeld (University of Wuerzburg) and Wei Tsang Ooi (NUS). The workshop received support from two projects funded by the European Union, Qualinet and CUbRIK.

During the workshop, we had an interesting panel discussion with the topic "Crowdsourcing in Mutlimedia Emerged or Emerging?" The members of the panel were Daniel Gatica-Perez from Idiap (who keynoted the workshop with a talk entitled, "When the Crowd Watches the Crowd: Understanding Impressions in Online Conversational Video"), Tobias Hossfeld (who organized this year's Crowdsourcing for Multimedia Ideas Competition) and Mohammad Soleymani from Imperial College London (together we presented a tutorial on Crowdsourcing for Multimedia Research the day before). The image above was taken of the whiteboard where I attempted to accumulate the main points raised by the audience and the panel members during the discussion. The purpose of this post is to give a summary of these points.

At the end of the panel, the panel together with the audience decided that crowdsourcing for multimedia has not yet reached its full potential, and therefore should be considered "emerging" rather than already "emerged". This conclusion was interesting in light of the fact that the panel discussion revealed many areas in which crowdsourcing represents an extension of previously existing practices, or stands to benefit from established techniques or theoretical frameworks. These factors are arguments that can be marshaled in support of the "emerged" perspective. However, in the end the arguments for "emerging" had the clear upper hand.

Because the ultimate conclusion was "emerging", i.e., that the field is still experiencing development, I decided to summarize the panel discussion not as a series of statements, but rather as a list of questions. Please note that this summary is from my personal perspective and may not exactly represent what was said by the panelists and the audience during the panel. Any discrepancies, I hope, rather than being bothersome, will provide seeds for future discussion.

Summary of the CrowdMM 2013 Panel Discussion
"Crowdsourcing for Multimedia: Emerged or Emerging"

Understanding: Any larger sense of purpose that can be shared in the crowdsourcing ecosystem could be valuable to increase motivation and thereby quality. What else can we do to fight worker alienation? Why don't taskaskers ask the crowdworkers who they are? And vice versa?

Best Practices: There is no magic recipe for crowdsourcing for multimedia. Couldn't the research community be doing more to share task design, code and data? Would that help? Factors that contribute to the success of crowdsourcing are watertight task design (test, test, test, test, test, test the task design before running a large scale experiment), detailed examples or training sessions, inclusion of verification questions, and making workings aware of the larger meaning of their work. Do tasks have to be fun? Certainly, they should run smoothly so that crowdworkers can hit a state of "blissful productivity".

History: Many of the issues of crowdsourcing are the same ones encountered when we carry out experiments in the lab. Do we make full use of the carry over? Crowdsourcing experiments can be validated by corresponding experiments that have been carried out in a lab environment. Do we do this often enough?

Markets: Many of the issues of crowdsourcing are related to economics, and in particular to the way that the laws of supply and demand operate in an economic market. Have we made use of theories and practices from this area?

Diversity: Why is crowdsourcing mostly used for image labeling by the community? What about other applications such as system design and test? What about techniques that combine human and conventional computing in online systems?

Reproducibility: Shouldn't reproducibility be the ultimate goal of crowdsourcing? Are we making the problem to simple in the cases that we struggle with reproducibility? Understanding the input of the crowd as being influenced by multiple dimensions can help us to better design crowdsourcing experiments that are highly replicable.

Reliability: Have we made use of reliability theory? How about test/retest reliability used in psychology?

Uncertainty: Are we dealing with noisier data? Or has crowdsourcing actually allowed us to move to more realistic data? Human consensus is the upper limit of what we can derive from crowdsourcing, but does human consensus not in turn depend on how well the task has been described to crowdworkers? What don't we do more to exploit the whole framework of probability theory?

Gamification: Will it solve the issues of how to effectively and appropriately incentivize the crowd? Should the research community be the ones to push forward gamification (Does any of us realize how many people and resources it takes to make a really successful commercial game?)

Design: Aren't we forgetting about a lot of work that has been done in interaction design?

Education: Can we combine crowdsourcing systems with systems that help people learn skills that are useful in real life? In this way, crowdworkers receive more from the system in exchange for their crowdwork, in addition to just money.

Cats: Labeling cats is not necessarily an easy task. Is a stuffed animal a cat? How about a kitten?

Saturday, August 24, 2013

What is multimedia?

These days a mirrored ceiling is an unambiguous call to take a photo.
Yesterday evening after the conclusion of a very successful First Workshop on Speech, Language, and Audio in Multimedia (SLAM 2013) in Marseille, participants naturally drifted to various scenic spots for debriefing, including the Vieux Port. There, over a glass of pastis (predictable, given the locale) the conversation naturally moved to the question, "What is multimedia?"

One obvious answer to the question is the Wikipedia definition of multimedia, "Multimedia is media and content that uses a combination of different content forms". The classic example, is of course, video, which has a visual modality and also an audio modality. Other examples include social images (for example, images on Flickr have a visual modality, but also have tags and geo-tags) and podcasts (which have an audio modality and also a textual modality included in their RSS feeds).

One can argue about that answer, for example, by pointing out that some people define multimedia as being any non-text media. For example, an image, like the one above. The image was taken at the new events pavilion in the Vieux Port in Marseille. The events pavilion is basically a set of columns with a plane laid on top of them, the bottom of the plane is shiny, so that when you stand under it you are looking up at a ceiling, which is a large mirror.

In my view, an image in isolation cannot be taken to be multimedia since it includes a single medium, name pixels. It become multimedia in conjunction with this blog post, which adds an additional medium, namely text.

Another dimension for the debate on multimedia is whether it must necessarily involve human communication. The combination of this image and this blogpost were created by me with the intent to communicate a message to a certain audience, i.e., the readership of my blog (which, as I have previously mentioned, is largely a few fellow researchers in conjunction with future instantiations of myself).

Researchers who share my view of multimedia, insist on the point that multimedia must contain a message. It must come into being as an act of communication and also be consumed in a process that involves the interpretation of meaning. This definition excludes a set of geo-tagged surveillance videos as being multimedia, although they would involve two different media, namely video content and geo-coordinates.

Note that when you require multimedia to contain a message created with explicit human intent, you enter a bit of a slippery slope. If a human being had set up the surveillance cameras with the specific intent of creating a body of information that would give fellow humans information on current street conditions, then we are back to multimedia.

The slipperiness of the definition of multimedia reveals to us something very important about our field. In order to know whether or not something is multimedia, it is not sufficient to examine the multimedia data, rather it is also necessary to look at the production and consumption chain. Multimodal data in some contexts remains just data, but if an act of encoding and decoding meaning is involved, then the same multimodal data must be considered to be multimedia.

A report on SLAM 2013 has appeared in SIGMM Records. The SLAM 2014 website went online immediately after SLAM 2013 and the anticipation is already building.

Sunday, August 11, 2013

Semantics for Multimedia Research: Getting the Definitions of "Semantics" Right

Mossy Tree

There seem to be two different definitions of semantics in use in the multimedia community. Having been trained as a linguist, I have a strong opinion about which one of these more useful for multimedia research.

The first I call semantics as interpretation. Basically, here, semantics is considered to be anything that a human might remark when viewing and trying to interpret multimedia. Concentrating, for the sake of example, on images, this first definition would consider the semantic analysis of the image above to result in the conclusion that the image depicts a tree. The image is associated with the semantics "tree" because someone looking at the picture can imaginably say, "Oh, this picture shows a tree."

The second I call semantics as signification. This is the definition of semantics that I argue is the more useful one. Signification has to do with the use of systems of signs. Systems of signs arise because humans interact with each other and in doing so develop communication conventions. Human language is the quintessential example of a type of system of signs.

These systems of signs are shaped by the nature and the capacity of our brains. However, in contrast to perception, the process of interpretation of a sign (or set of signs) requires making reference to a set of "guidelines of use" that are not primarily a product of human physiology, but rather owe their existence to human interaction. Some sign systems are established quickly, or even in the course of a single conversation or exchange, but in general the process of human language evolution is measured in millennia rather than minutes.

This semantics-as-signification definition can be stated more formally as: 
Semantics is the creation and interpretation of individual and/or inter-playing signs guided by human cognition and communication convention.
Note that dictionary definitions of "semantics" mention "signification" and "signs": see Merriam Webster,  OED and Wikipedia, suggesting that the semantics-as-signification definition is the more generally accepted version, and that the semantics-as-interpretation definition may be rather particular to the field of multimedia research. I will argue that it is not only particular to the field, but that it is one "innovation" that we are actually better off without.

Let's revisit the image above in light of the semantics-as-signification definition. Under this definition the image above is also associated with the semantics "tree", but not merely because someone looking at the picture can imaginably say, "Oh, this picture shows a tree." Rather, critically, it is because, also, "tree" belongs to a larger system of signs. It is a concept that humans agree is part of the way in which we communicate about the world.

Let's turn now to consider the status of the moss growing on the tree in the image. Both definitions would associate the image with the semantics "moss", since "moss" is a concept just like "tree". However, we can imagine a human looking at the moss in the picture and "seeing" something different. That person might remark about this image "Oh, this picture shows north." This remark is enough to confirm that under the semantics-as-interpretation definition, the image can be associated with the semantics "northiness".

However, in order to come to a conclusion concerning the status of "northiness" under the semantics-as-signification definition, we need to look a little further.

Specifically, for the semantics-as-signification definition, we need to be able to assume that "northiness" belongs to a larger systems of signs used to communicate. In other words,  we need to convince ourselves of the existence of a system of signs under which this kind of image communicates "northiness".

OK. That's easy. Effectively, we have just made up exactly such a system. I tell you that this image depicts "northiness" and you can judge the next image that I show you. We will both agree that this new image is associated with "northiness". We have just invented a new convention and are using it to interact. We may not want to claim that we have created an entirely new system of signs, but we have just "re-newed" the existing system by extending it with a new sign.

Is it always possible to identify a system of signs such that we are justified in applying the semantics-as-signification definition? Is the difference between the two definitions irrelevant?

We can safely assume that, yes, it is always possible to identify such a system of signs. Human brains are creative and flexible. If I gave you another picture similar to the one above, would you be able to apply our new concept of "northiness" to it? I would imagine that you would apply it flawlessly. Also, human interaction are directed towards communication. If I use a word that you don't know, your first reaction is to try to figure out what I meant by that word. Unlike a conventional computer, your cognitive system does not shut down and throw an "input unknown" message, but instead it makes an attempt to integrate the new word into its inventory of conventions.

In sum, if no existing system of signs is already available, presto, we can create one. Further, our natural tendencies predispose us to create one automatically, frequently without even realizing that we are doing it.

However, even if we agree we can always force semantics that complies with the semantics-as-interpretation definition to fit the semantics-as-signification definition, it might not always be a good idea to do so. The difference between the two definitions is very relevant indeed. 

Look at the problem with "northiness". In order for someone to be able to use "northiness" to communicate, that person would have to have read this blog post. If we want to consider "northiness" as part of the semantics of the image, the fact that people need a specialized background knowledge imposes a rather constricting limitation on the number of people who would have access to the "semantics" of the image (i.e., who could productively make use of "northiness" semantics), and thus on the applicability of our multimedia analysis.

Further, "northiness" can be seen as a rather irresponsible invention on my part. The connection between moss growth and direction is tenuous at best, and I shouldn't be suggesting that moss is a reliable indicator for finding one's way out of a woods. That could go very wrong. Personal (in contrast to conventional) interpretations threaten to limit the applicability of our multimedia analysis.

The key issue is this: If we force semantics that complies to the semantics-as-interpretation definition to fit the semantics-as-signification definition, we lose track of our assumptions about the nature of the underlying system of signs. We don't know if we should now throw research effort into creating visual detectors to identify "northiness" semantics in images, or if "tree" detectors are more important. By forcing ourselves to reason carefully about the underlying systems of signs, we can make those kind of decisions in a more informed manner.
 
Note that I am not suggesting that it is possible to sit down and enumerate all the signs that are part of any given system of signs. These systems are not finite; nor are they mutually exclusive. (My suggestion for how to best attack this issue is to turn to pre-lexical semantics, previously discussed here.)

What I am arguing is that the "mere" act of explicitly acknowledging that the system of signs must necessarily exist provides a productive constraint on our models because it prevents us from extending semantic interpretations unconsciously or arbitrarily (e.g., it prevents me from suddenly declaring the reality and importance of "northiness" without further substantiation.)

Adopting the semantics-as-signification definition implies understanding meaning to be something that arises via a process of negotiation between two or more human communicators with respect to a set of established conventions. In the absence of consensus between multiple humans, there is no meaning, i.e., no semantics. This is the theoretical basis for choices to focus multimedia research on analyzing those aspects of images and video which have a high inter-annotator agreement.

Am I opening an "If a tree falls in the forest and no one hears it does it really make a noise" debate? The image I have chosen above perhaps even invites that. However, let's close with another related image and question: "If this picture shows northiness and no one else sees it, do we really want to consider northiness to be a semantic concept for the purposes of multimedia research?" My point is that we get a lot further a lot faster if we just accept that the answer is "no".

It's not that we don't find "northiness" interesting. In fact, visual detectors capable of predicting the direction of the compass faced by the camera at the moment the image is captured have a number of potential applications. It's just that unless we stop for careful consideration before considering "northiness" to be part of the image semantics, we are in danger of sliding down a slippery slope. This slope leads to the quite unscientific habit of inventing our systems of signs as we go along, convenience-driven and possibly largely unconsciously.

Sunset straight on


Saturday, March 30, 2013

Multimedia Readymades

This blog post is a continuation of http://ngrams.blogspot.nl/2013/03/multimedia-bits.html and a response to Cynthia Liem's call to collect "hidden gems" of internet multimedia made during her TedX Delft talk "Every bit of it" (cf. http://youtu.be/ykkXdjr0rfI?t=15m58s) Cynthia says that original bits of multimedia that we share on the Internet have the feel of "randomness" or of "low quality", but that what they are are "entry points" to things of value, if we can discover them and polish them. In this blog post I relate discovered bits of multimedia to the surrealist concept of "Readymades".

An art exhibition that I visited some 25 years ago in Frankfurt was probably what set me first to thinking about hidden gems and the process by which value is assigned to what would conventionally be considered mundane.

My most recent hidden gem is a video that captures the comments of people on something that has been created not by an act of coming-into-being, but by an act of putting-into-context.

From one perspective, the video is about Fountain, which is one of the Readymades of Marcel Duchamp. Wikipedia gives us the definition of the Readymade from André Breton and Paul Éluard's Dictionnaire abrégé du Surréalisme: "an ordinary object elevated to the dignity of a work of art by the mere choice of an artist." 

The Fountain is a urinal that has been taken out of context in two ways: first, it lies flat rather than hanging on a wall in the position it would need to be in order to be used, and, second, it was submitted by Marcel Duchamp in 1917 as a work of art to an art exhibition.

One could quip, "Beauty lies in the eye of the beholder." and let it go at that. However, scratch a little deeper, look beyond the shock-value of the object being a urinal, and a different message becomes clear: The artifact itself has little importance, and merely provides a trigger for the process of Fountain becoming something interesting and worthwhile.

Marcel Duchamp 'FOUNTAIN' - IS IT ART? from arlen figgis on Vimeo.

From another perspective, the video is about what happens when you take a widely-recognized work of art and display it to people out of context. In the video, the urinal is put into a public toilet in Liverpool and people, who recognize the urinal as Fountain, are asked to comment on it.
 
Of all the people in the video, only two comment on the fact that they are actually standing in a toilet looking at a toilet. The relative inattention to this point suggests that the fact that Fountain is finally in its "home" surroundings does not have much impact on people's opinions of it. No one in the video is looking at the urinal and having anything that at all related to a "The-Emperor-has-no-clothes" moment. Instead, they seem to have the same thoughts and feeling as they did when they walked into the toilet: they are interested, and they acknowledge it as something worthwhile.

I consider this video to be rather unfinished (yet a "diamond in the rough") because it has the power to make a point that it does not explicitly make. The un-made point is this: it is non-trivial to undo the Fountain effect, i.e., the urinal stubbornly resists returning to un-interestingness. Once a gem has emerged from a mundane object, the gem-status is difficult to shake.

These two perspectives on what this video is about represent two poles of a spectrum of interactions that we (as users, uploaders and viewers) have with bits of online multimedia that people capture and upload to the internet.

In some moments, we amuse, educate and otherwise occupy ourselves through layers of rediscovery, and the popularity, quality, origin, and perhaps even topic of the original multimedia object could not be less relevant.

In other moments, we forget about  rediscovering hidden gems and return to what it widely-acknowledged to be interesting or worthwhile, we cling to The Cannon or flock to watch the blockbusters.

Our goal as multimedia information retrieval researchers should be to develop techniques that support this entire spectrum.

In Frankfurt 25 years ago, my encounter with Readymades revealed to me that it is not particularly useful to assume that there is a sharp boundary between creation and discovery. It made clear that significance arises through the dialogue representing an interplay between a large number of voices representing the general public and more limited number of voices recognized as authorities.

These poles exist now, they existed 25 years ago (pre-Internet), it was happening in 1917, and from there it seems a relatively straightforward extension to the idea that they were there before and that their importance will continue.

It is multimedia systems that give us access to the hits and classics, but that also allow us to discover the triggers ("entry points" in Cynthia's words) from which interesting and worthwhile objects emerge and to support the interplay of contributions and opinions necessary for emergence.

It's a difficult problem. I rather think that the number of people that share my understanding of my hidden gem is quite limited, and that we would need a retrieval or recommendation system that would reach all of them in order to really add any polish. Or maybe it is enough for the gem to be personal, although I am far from sure that it is easy to ensure this video is still discoverable in future years when I again return to the topic of the emergent value of the mundane.

Friday, March 29, 2013

Multimedia Bits

Cynthia Liem recently gave a TedX Delft talk called "Every bit of it". I have the pleasure and the honor of being her colleague at the Delft Multimedia Information Retrieval Lab. I missed being at the talk in person, but finally found time today to watch it on YouTube.

What she is saying is so critical---it at the same time both fresh and timeless---that the talk deserves a more in-depth reaction than a tweet or re-tweet. This post summarizes the message that I heard in Cynthia's talk.

Cynthia makes the point that every bit on the Internet has meaning to the original person who put it there. These are of course, multimedia bits, that she is speaking of videos and images that have been captured by people and shared on the Internet. An important question in this era of Big Data: each of these "bits" of multimedia is captured by someone for some reason. Cynthia tells us that we can add worth to these bits by enhancing them with other bits; in particular, she shows us wondrous transformations that can be brought about by adding music to video.



Towards the end of the video, she says that a big question that with face with multimedia is "What is relevant?" http://youtu.be/ykkXdjr0rfI?t=14m1s

She points out that we tend to focus for the obvious in our understanding of relevance, e.g., popularity and quality, and that because of this focus, we miss material that people do not know exists.

Instead, the "bits" of multimedia on the Internet should be seen as an entrance to the world, not as the final product, but a place to start. A diamond in the rough that needs to be polished in order to add value.

At the end of the video, she asks the audience to keep their eyes open for a rediscovered hidden gem....I discuss my gem in my next post: http://ngrams.blogspot.nl/2013/03/multimedia-readymades.html

Friday, February 15, 2013

Crowdsourcing for Multimedia: ACM Multimedia and The Crowd

Crowdsourcing for multimedia is a set of techniques that leverage human intelligence and a large number of individual contributors in order to tackle challenges in multimedia that are conventionally approached using automatic methods. Exploiting the crowd means taking advantage of human computation where it can help support multimedia algorithms and multimedia systems the most.

ACM Multimedia 2013 has introduced a new Crowdsourcing for Multimedia area:
http://acmmm13.org/submissions/call-for-papers/#crowdsourcing
The area cuts clean across traditional multimedia areas, touching upon nearly every topic relevant for multimedia. The area casts a wide net to include the full range of research results and novel ideas in multimedia that are made possible by the crowd, i.e., they exploit crowdsourcing principles and techniques.

How did this new area arise? Crowdsourcing's grand debut at ACM Multimedia is CrowdMM http://www.crowdmm.org/. On Octber 29, 2012 the CrowdMM 2012 International ACM Workshop on Crowdsourcing for Multimedia was held in conjunction with ACM Multimedia 2012 in Nara, Japan. The workshop kicked-off with a keynote entitled "PodCastle and Songle: Crowdsourcing-Based Web Services for Spoken Content Retrieval and Active Music Listening" by Masataka Goto of the National Institute of Advanced Industrial Science and Technology (AIST), Japan. These two systems dazzled the audience and gave us a foretaste of the possibilities that the power of the crowd opens for the multimedia community. An interesting day of talks, posters and discussion ensured, culminating in a panel (summarized below).

The organizers of CrowdMM 2012 hope that both the ACM Multimedia area (focused on groundbreaking research results) and also CrowdMM workshop (focused on methodology, exploratory work and on researcher interaction) will provide a solid foundation that allows crowdsourcing for multimedia to grow within the multimedia community to reach its full potential.

"Crowdsourcing for multimedia: At a crossroad or on a superhighway?"

Summary of the Panel Discussion at CrowdMM 2012 

What is the potential of crowdsourcing for ACM Multimedia?
We need The Crowd to allow us to build larger, up-to-date dictionaries for multimedia annotation. We also need The Crowd to create ground truth at a large scale.

The combining techniques for active learning and for incentivizing human contributions will contribute to many different specific multimedia problems.

In all cases, both quality control will be important and also making it fun for The Crowd to contribute, e.g., continuing to build entertaining games to collect Crowd contributions. User engagement breeds quality: for example, Songle provides services that are enjoyable to use and attracts good workers naturally. 
 
What are the limitations of crowdsourcing for multimedia?
Data from non-experts is valuable, but for some tasks we need experts. We need methods that will allow us to identify experts, for example, with domain knowledge. The multimedia community can potentially address the problem of having access to "the right crowd", by joining forces to cultivate a community of crowdsourcing workers who deliver high quality annotations for specific multimedia domains.

How would ACM Multimedia be different had crowdsourcing been invented 20 years ago? If crowdsourcing had existed 20 years ago, we would make much more effective use of active learning paradigms, i.e., algorithms that would interactively query human annotators to obtain new labels for certain multimedia items.

Crowdsourcing makes possible large scale multimedia annotations. Even if crowdsourcing existed 20 years ago, we may not have the tools and techniques to deal with large scale data.

The challenge today is to realize the potential of multimedia, both in venturing into new domains for research and also in scaling up our systems to exploit larger amounts of human labeled data for training and also for evaluation.

In short, the panel concluded, it’s up to ACMMM to catch up with the crowd.

A big thank you to my fellow organizers for the work that they put into making CrowdMM 2012 such a success:
IMG_0333

Wednesday, December 21, 2011

The MediaEval Model for Benchmarking Evaluation

Currently, I'm working to put together the survey for MediaEval 2012. This survey will be used to decide on the tasks that will run in 2012 and also will help to gather information that we will use to further refine the MediaEval model: the set of values and organizational principles that we use to run the benchmark.

At the workshop, someone came up to me and mentioned that he had made use of the model in a different setting, 'I hope you don't mind', he said. Mind? No. Quite to the contrary. We hope that other benchmarking initiatives pick up the MediaEval model and elements of it and put them to use.

I have resolved to be more articulate about exactly what the MediaEval model is. There's no secret sauce or anything -- it's just a set of points that are important to us and that we try to observe as a community.

The MediaEval Model
The MediaEval model for benchmarking evaluation is an evolution of the classic model for an information retrieval benchmarking initiative (used by TREC, CLEF, TRECVid). It runs on a yearly cycle and culminates with a workshop where participants gather to discuss their results and plan future work.

The MediaEval attempts to push beyond existing practice, by maximizing the community involvement in the benchmark. Practically, we do this by emphasizing the following points:
  1. Tasks are chosen using a survey, which gathers the opinion of the largest possible number of community members and potential MediaEval participants for the upcoming year.
  2. Tasks follow the same overall schedule, but individual tasks are otherwise very autonomous and are managed by the Task Organizers.
  3. The Tasks Organizers are encouraged to submit runs to their own tasks, but these runs do not count in the official ranking.
  4. The Task Organizers are supported by a group of five core participants who pledge to complete the task "come hell or high water".
  5. Each task has an official quantitative evaluation metric, which is used to rank the algorithms of the participating teams. The task also, however, promotes qualitative measures of algorithm goodness: i.e., the extent to which an algorithm embodies a creative and promising extension of the state of the art. These qualitative measures are recognized informally by awarding a set of prizes.
In interview footage from the MediaEval 2012 workshop, I discuss the challenge of forging consensus within the community.



One of the important parts of consensus building is collecting detailed and high-coverage information at the beginning of the year about what everyone in the community (and also potential members of the community) thinks. And so I am working here, going through not only the tasks proposals, but also other forms of feedback we've gotten from last year (questionnaires, emails) in order to make sure that we get the appropriate questions on the survey.

It always takes so much longer than I predict -- but it's definitely worth the effort.

Wednesday, September 28, 2011

Search Computing and Social Media Workshop

Today, in Torino, Italy, was the day of the Search Computing and Social Media Workshop organized by Chorus+, Glocal and PetaMedia. Being the PetaMedia organizer, I had the honor of opening the workshop with a few words. I tried to set the tone by making the point that information is inherently social, being created by people, for people. Digital media simply extends the reach of information, letting us exchange with others and with ourselves over the constraints of time and space.

The panel at the end of the day looped back around to this idea to discuss the human factor in search computing. We collected points from the workshop participants on pieces of paper to provide the basis for group discussion. I made some notes about how this discussion unrolled. I'm recording them here while they are still fresh in my head.

We started by tackling a big, unsolved issue: Privacy. The point was made that the very reason why social media even exists is that people seem driven in some way to give up their privacy, share things about themselves that no one would know unless they were revealed. Whether or not users do or should compromise their own privacy by sharing personal media was noted to depend on the situation. For some people it's simply, obviously the right thing to do. Concerns were raised about people not knowing the consequences: maybe effectively I am a totally different person five years from now than I am now. But I am still followed by the consequences of today's sharing habits. In the end, the point was made that if the willingness to among users to share stops, we as social media researchers have not much else left to examine.

Next we moved to the question of events in social media: Human's don't agree about what constitutes and event. Wouldn't it just be easier to just adopt as our idea of an event whatever our automatic methods tell us is an event? Effectively we do this anyway. We have no universal definition of an event. There may be some common understanding or conventions within a community that define what an event is. However, these do not necessarily involve widespread consensus: they may be personal and they may evolve with time. For example, the event of "freedom"? Most people agreed that freedom was not an event.

An event is a context. That's it. At the root of things, there are no events. Instead, we use concepts to build from meaning to situational meaning -- to the interpretation of the meaning of the context. Via this interpretation, the impression of event emerges. In the end, meaning is negotiated.

If we say events are nothing, we wouldn't be able to recognize them. Or, does the computer simply play a role in the negotiation game. The systems we build "teach" us their language and we adapt ourselves to their limitations and to the interpretative opportunities that they offer.

Then the question came up about the problems that we choose to tackle as researcher. "Are we hunting turtles because we can't catch hares?" This bothered me a bit, because assuming you can easily catch a turtle, they are quite difficult to kill because of the shell. The hare would be easier. Do our data sets really allow us to tackle "the problem"? The question presupposes that we know what "the problem" is, which may be the same as solving the problem in the first place. Maybe if we can offer the user in a give context enough results that are good enough, they will be able to pick the one that solves "the problem". Perhaps that's all there is to it. Under such an interpretation, the human factor becomes an integral part of the search problem.

In the end, a clear voice with a succinct take home message:
How can we efficiently combine both the human factor and technology approaches?
"The machine can propose and the user can decide."

The discussion ended naturally with a Tim Berners Lee quote, reminding us of the original intent of social effect underlying the Web. We adjourned for some more social networking among ourselves, reassuring ourselves that as long as we were still asking the question we shouldn't expect to find ourselves completely off track.

Friday, October 29, 2010

ACM Multimedia SSCS 2010 Workshop on Searching Spontaneous Conversational Speech

The Fourth Workshop on Searching Spontaneous Conversational Speech took place on 29 October 2010 at ACM Multimedia. Papers were presented about techniques for speech retrieval, speaker role recognition, spoken term detection and concept detection. Invited speakers addressed challenges for the future of spoken content retrieval, including interview data, multimedia archives and the Spoken Web. The demonstrations were a highlight of the workshop. These were first introduced in a boaster session and then presented to workshop participants in an interactive session. Here's the Wordle Word cloud made from the title and the abstracts of all the papers presented!

Currently, we are getting ready for an upcoming special issue on searching speech in ACM Transactions on Information Systems.

Sunday, June 6, 2010

Looking for a Scientific Programmer

I'm starting a cool new project on speech-based access to images, but I am in need of a programmer. I'm trying to find the right person -- ideally I would like someone who also had an interest in the process of design and evaluation of the system. The person probably just finished their masters and is trying to get an idea of an area for a PhD, or just generally thinks that one year of experience in the Multimedia Information Retrieval Lab at Delft University of Technology would be enriching. Unfortunately, trying to get someone like this just led to me loosing my dream candidate to a PhD program in Groningen. Yikes! The project's starting on 1 September 2010.

The formal qualifications are listed below. Thanks in advance if you help me find a match between my needs and a candidate.

Profile for scientific programmer in the Delft Multimedia Information Retrieval Lab at the TU-Delft
Contact: Martha Larson m.a.larson@tudelft.nl
  • Experience developing web applications using a web development stack, (one of LAMP, Java/Tomcat, ASP.NET/C#)
  • Experience with designing HTTP-based server APIs
  • Alternatively or in addition: Experience with html/Javascript/AJAX/Flash/Silverlight
  • Alternatively or in addition: Interest or experience with Android
  • Experience with speech recognition, dialog systems, audio spatialization a benefit
  • Experience with programming in a research environment a plus
  • Proficiency in English, both spoken and written
The person needs to be an EU citizen, but if I find a great candidate who is not, I am willing to attempt to "battle the system" to get him/her.

P.S. This post represents an experiment in making use of my social network. If was were more up-to-date I suppose I'd be using Linked-In or Facebook, but neither are come naturally to me, somehow.

Thursday, March 18, 2010

Time to play

What's the difference between a single image and a video? Well, video is a timed medium, otherwise called a time-continuous or time-synchronized medium. It's impossible to take in at a glance, and in order to appreciate it, or derive any benefit from it at all, you have to devote time to watching it.

Watching would be more efficient if we didn't need to watch from end to end, but rather had some sort of a road map for the video: an intelligent players that would give us signposts, provide us with an indication of where the video could be most interesting.

I was invited to give a position statement at a session on search at ICTDelta 2010, a larger IT event in the Netherlands. I took the position that we need to have intelligent multimedia players that give us clues as to where the video is the most interesting as my position. The position statement was in Dutch, but I made an English version in the form of a YouTube video.

Thursday, October 22, 2009

Well, behind every joke there's some truth

The winner of the ACM MultiMedia Grand Challenge at ACM MultiMedia 2009 was "Joke-O-Mat: Browsing Sitcoms Punchline by Punchline." This application uses speaker diarization and laughter detection to annotate sitcoms and present them to the viewer in an interface that allows presents jokes ranked by laugh reaction, grouped by character and associated with context. Joke-O-Mat underlines the importance of the speech track for multimedia access.



What to do when multimedia doesn't contain a laugh track? In VideoCLEF 2009 we ran a narrative peak detection task. The goal was to detect points in videos where viewers perceive heightened dramatic tension. Today, CLEF working notes, tomorrow our own Peak-O-Mat?