Vision de San Diego

in lost English below

CIC se termine sur un rythme connu, éprouvant mais toujours réjouissant, discussions et présentations intéressantes entre autres à propos de display, l’arrivée d’outils d’optimisation, l’extension des CMFs [mes quelques notes sur la conférence CIC 2016 ici] et bien sûr la fatigue due à la distortion journalière du temps grace aux inévitables et indispensables bières d'après les sessions officielles.

16 ans après avoir suivi les élections américaines de Montréal - donc presque localement - je renouvelle l'expérience, cette fois ci de la Californie et dans le dernier fuseau horaire des résultats où l'issue fait peu de doutes. Chaque soirée à partir du mardi soir était animée de manifs anti nouveau président dans centre ville  de San Diego - où se déroule ma conférence couleur cette année - avec l'impression depuis de se réveiller chaque matin dans la mauvaise time line de Retour vers le Futur.

and now in lost English

CIC is getting over soon under its usual rhythm,  demanding but always gratifying, discussions and presentations were interesting on various topics such as display, new optimisation tools, the extension of CMFs [you can read here my few notes about the conference CIC 2016] and of course your body getting more tired every day because of the time distortion... time distortion mainly due to the inevitable and vital evening beer sessions after the official sessions.

16 years after having followed the US election from Montréal - so almost as a local - I renew the experience this time from California. The local time zone makes the doubts about the final results. Each evening from Tuesday demonstrations were happening in downtown San Diego - where my conference is taking place - with the sensitive impression to wake up each following morning in the wrong time line of Back to the Future.

Berlin Amsterdam New-York San-Diego

maybe in English below

Voyage un peu long mais ca va, de la place pour mes jambes donc je ne peux pas trop me plaindre et de plus tous mes avions ont réussi leur atterrissage. J'ai gagné pas mal de points sur Foursquare avec tous ces aéroports ainsi que quelques taches de sauce tomate sur mon t-shirt blanc... A retenir pour les futurs voyages: mettre un t-shirt noir et éviter les plats en sauce.

L'arrivée à San Diego ressemble à celle que j'ai eu à San Antonio ou Albuquerque. L'aéroport est vide, il fait chaud, il fait nuit, je ne sais plus dans quel fuseau horaire j'évolue. Mais rapidement je trouve mon bus, 2$ et 12min de trajet et j'arrive à mon hotel. Là je fais la connaissance de mon voisin de chambre, Alexandre prof brésilien comme moi venu écouter et aider sur place la conférence CIC. Il temps de s'effondrer, la session "short course" dont je suis un peu responsable débute dans 7h.

in live translated English

Journey a bit long but still ok, I had room to squeeze my legs so I can't really complain, besides my numerous airplanes did succeed in each of their landing.  I won a few points in Foursquare with all these airports as well as a few tomato sauce stains on my white shirt... Notes for the future trips: wear a black shirt and avoid pasta with tomato sauce.

The arrival in San Diego reminds me those I had in San Antonio or Albuquerque. The airport is empty, it's dark, it's warm, I don't know in which time zone i'm evolving. But quickly I find my bus, 2$m and 12min later I'm in my hotel. I meet my room neighbor for the time of the conference, Alexander a Brazilian professor coming like me to help and listen this week at CIC. It's about time to collapse, the session "Short Course" I'm involved in is starting in 7h.

Vision de Jérémie - Visit the Charli's factory

Cupertino c'est fini pour cette semaine et il est temps de se rapprocher de SF pour le weekend. En remontant la vallée je fais un stop au campus Google. En chemin je passe devant les Microsoft, Facebook... seuls les noms inscrits sur les buildings ou les bus privés de ces entreprises vous rappellent que vous êtes bien dans la Sillicon Valley et que c'est ici que ca se passe.

11:30am
je pénètre sur le campus Google. Cet endroit, la Sillicon Valley, est un Disneyland de la Tech. Et pour faire court tout est vrai, les vélos en libre accès, les gens faisant du yoga sur la pelouse, le terrain de beach volley, les statues à l'effigie des dernières Release d'Android.

A photo posted by jeremie Gerhardt (@mrbonsoir) on Mar 28, 2016 at 4:53am PDT

Mon déjeuner d'affaire et networking se finit, fort agréable, toujours cool de rencontrer des gens intéressants et de comprendre leur parcours géographique, professionnel et personnel. Le monde de la couleur est un monde à part, en même temps je ne connais que celui la...

4:33pm
après avoir visité deux Best-Buy, équivalent d'un Saturn ou d'un Darty j'échoue dans l'achat d'un ordi, mais bon c'est pas de ma faute et ca m'a permit de voir autre chose de la région.

Le rapprochement de SoMa est long est lent, mais à chaque rue des noms évocateurs s'affichent devant moi, Pinterest, Yahoo, Linkedin, Twitter... Un autre aspect de la Sillicon Valley. Je dépose mes affaires chez ma nouvelle hôte rencontrée à Berlin et dans la région pour quelques temps.

8:00pm
avec grand plaisir je retrouve l'ami Tarun dans un restaurant japonais Ken Ken Ramen pour quelques ramen vous l'aurez compris. C'était pas mal. Mon hôte nous a rejoint et approuve l'endroit.

Le reste de la soirée c'est un verre de vin quelconque sur Valencia et la vue sur le centre ville du balcon avant de s'écrouler. Schön schön.

Enter the matrix

Un autre entretien marathon qui arrive, je me dis que recommencer à courir régulièrement il y a deux ans de cela n'était pas une si mauvaise idée.

Ce n'est pas mon premier interview de la sorte où l'on vous reçoit, vous installe dans une petite salle de réunion aux murs blancs, vous escorte aux toilettes, vous apporte des cafés et où vous rencontrez une nouvelle tête toutes les 45min, au programme 8 ou 9 personnes. A ce moment vous discutez, chaque interlocuteur vient avec votre cv ou pas et vous pose des questions, le tableau est prêt et vous aussi.

Pour faire court, ca peut peu durer longtemps, ca ressemble beaucoup à la Matrice.

10:15am
Je rentre dans la matrice.

5:30pm
je sors de la matrice.

Un peu fatigué j'avoue, je refais le match avec l'ami Nicolas, le soleil est encore là et le climat plutôt cool. Le futur dira.

A video posted by jeremie Gerhardt (@mrbonsoir) on Mar 16, 2016 at 1:56pm PDT

Algo in mobile phone camera

Smartphones are becoming our primary camera and our primary way to consume images. The technical differences between those devices are shrinking. How do you differentiate between them?

Considering all devices coming with approximatively the same hardware from sensors to optic, the differences should come from the software. if you take Android OS, despite its presence on most of the smartphone, the manufacturers using this OS can still pre-load their devices with advanced options.

My point here is not to list or say which one is better than the other, but to highlight all the options now available. What I think is interesting here is to see what is considered to be granted from the user point of view: auto-focus, white balancing, hdr, face detection, low light condition, panorama and to wonder what people really understood of these tools. The marketing department surely has something to say about the last point.

To know a bit about the production workflow around this problematic, I really see the the battle of new algorithms/automatic image as the way for company to market their image (see the last Iphone campaign). A bit like the battle between film manufacturers (Kodak, Agfa, Fuji...) back in the days, where for the same ISO sensitivities (for me my favorite was 400 color by Fujifilm) the same color signal will appear slightly different on paper. The camera allows you to record the scene and the film/digital camera chosen will print the look of the final image.

So what can you really do? A lot will answer the emergency color scientist. It is super important and very interesting to study how our visual system is functioning, how it adapts with the light condition (eg. how to improve an image when observe on your phone in low light condition). All sounds pretty cool to me, color scientists can be useful.

La suite dans le futur.

Personal insights on color science

Context
In a previous post I talked about the last event in my field I did attend. Now I want to talk about my perception of this domain which is called color science. I'm pretty sure it can be applied to other fields of research as well.

From the first time I joined this community, from article reader, article contributor to reviewer, committee member and session chair my understanding of what is color science has evolved. One important thing is to stay humble, especially with the new comers. I have been one them, it was impressive. Impressive because you meet the people, authors of research articles that are part of the foundation of you work. You can add a person, a voice to written words, it's actually pretty cool.

There aren't thousand concepts to understand/enter the world of color science. Like in every fields it's about observation and trying to explain what's happening. But here it's all about light - its spectral properties - how we perceive this signal - a single light source to an image in the visible spectrum - and how can we develop robust scientific/engineering "stuffs" around it. What I find interesting is to witness what is the new thing coming each year, how a technical improvement can open a door for further applications.

Color trends
Among the research sub-fields presented at CIC this year I want to come back on four of them.

There is the recurrent discussion about color metrics, from a purely mathematical/geometrical approach to a more perception-wise approach trying to add an average human appreciation of the difference between two signals. Having a good metric is always helpful to evaluate your algorithm/experiment. Over the years the metrics are evolving, context is important (from display calibration to color textile differences...).

There is the what I call "purely geometrical approach" discussion where having a signal as vector of n values - for n wavelength -  a group of sensors - basic configuration made of three basis like RGB basis - you want to know the value of this signal once projected on the known basis/sensors. From that you can jump into optimization, addressing various problems such as finding the scene illuminant/white point, study metamerism. It seems obvious but it's not.

There is printing and 3D printing - there I meant color 3D printing. Just think of how to design a color test-chart for such printing system. HDR display is also coming stronger than ever. What is interesting with these two examples is that they both require to know your workflow, they are the "end" of a process chain: you need to understand the acquisition process to do a good reproduction. Understanding the use of the technology is obviously required.

On the last paragraph one can add the understanding of gamut mapping and how you "move" into your color space as something very important. For printers you have multi-inks system changing the shape of the color space available. For high resolution TV and HDR screen the color gamut shape may not change a lot - almost - but the variability of screen size, intensity scale, technology available make it difficult - to be understood as something cool and challenging for me - to offer a comfortable experience to the user among the different platforms.

Now that I'm a bit more in control with the tools/concepts in my field and sub-fields I have the tendency to prefer the projects combining several concepts - like high quality printing and movie post-production - and I always appreciate to hear how the authors are presenting their projects, which story they are telling us.

CIC visiting Darmstadt

What is CIC you may ask yourself? It's stand for Color Imaging Conference, a conference about color and imaging. This year it took place in Darmstadt DE. The last 22 editions always took place in the US, last year it was in Boston MA, two years ago in Albuquerque NM, three years ago in Los Angeles CA, four years ago in San Antonio TX and that's it for my involvement. Next stop is San Diego CA in November 2016.

I'm a regular attendee, I joined this community already ten years ago alternating between CGIV, AIC, EI and CIC. Depending of the event you will meet a slightly different crowd or so to say different crowds will meet allowing to go deeper in the various fields represented. But for sure it's about imaging, color, perception, printing, archiving, image acquisition, color management, camera and display calibration, gamut mapping and more.

This year almost 200 persons were attending the event in Darmstadt. There is a kind of routine in such event and being part of the committee allows you to see the people interaction with a special look. It's very special to see the attendees - former colleagues, friends, known members of this community - arriving from everywhere almost - from North America, Europe, Asia, Australia... - and being all jet-lagged. Even if you are traveling in the same time zone you will end up jet-lagged. First of all the schedule is tide and you have to use the "free" time to talk with everybody. Sharing a meal or a beer is usually very appropriate. As a result you barely have time to rest, but the kind of adrenaline you get from meeting the crème de la crème of the color scientists keeps you awake.

Cyborg time

About two years ago I started with a friend - who happen to be a color scientist as well - a series of research experiment having for goal to study projector displays and wondering if we could evaluate some of theirs properties - such as response curve and color gamut - without proper measuring device - meaning without expensive measuring devices.

Said like that I admit it doesn't sound very sexy. But that were the fun come in, it is not because it doesn't sound über cool that the approach can't be fun. Inspired by the work of other researchers where instead of using measuring devices experiments were conducted using a panel of human observers. A series of images were presented to the observers. Based on their decision, to say if pairs of color patches were identical in brightness/intensity - one made of a single gray continuous value and the second made using halftone technique - the famous response curve could be described. There is so much things you can do with the response curve but I will not pursue in that direction today.

Our idea is simple and we are not the first to have had this idea: to replace the observer by a camera, a webcam. Three simple reasons to do so: for having been several time one of the observer I know it is super annoying to be part of such experiment, mimicking an eye with a camera is a nice challenge and webcam are cheap. And not to mention that opencv is there to avoid you to loose to much time in accessing the video stream of your webcam and programming in Python is pleasant.

To be short, we are re-doing a pair single color patch comparison. One patch is a continous patch and the second halftoned.  The project is called devForWebCam, it's programmed in Python and located here. The code should help to setup an experiment in order to gather data.

CIC 22 in Boston

For its 22th edition the Color Imaging Conference or CIC for the connsoisseurs took place in Boston. Comparing to last year in Albuquerque (NM) the color LUT did change a bit: yellow and blue for the desert and the sky to red and about 50 shades of autumn for the buildings and trees.

If as the previous editions the crowd of attendees remains similar - la crème de la crème of the color scientists - you can detect a slight dominance according to the conference location or with whom is organized the event. This year the keynote sessions where for both color scientists (CIC) and medical imaging scientists (IADP), then sessions were ran in parallel.

The joint keynotes brought interesting discussions. They were highlighting another practices of imaging system - like microscope - in the medical world. That is not a surprise that the imaging system described can provide very different visual results, from one microscope to the other the data do not appear identical to human observers but the extraction of information should. In one word there is no reference images or colors when the practicians is looking at samples, but they know that each patient is different and can base their diagnostic on their experience. In comparison to the CARS event, the IADP was much less about computer assisted radiography and more about image analysis (at least for what I have seen).

The day before the real opening of the conference is the short course day. Professionals, experts in academia or industry are giving lectures on color science topics. After chairing this session last year in Albuquerque NM I could follow two courses in Boston: one on color display given by Gabriel Marcu from Apple and a second on Color Rendering Index and Lighting given by Wendy Davis from University of Sydney. It is always refreshing to take part into these courses, to re-learn about display technology, display calibration, lighting technology and equally important how our comprehension of color science has evolves over the years and how new technologies force to change our approaches.

One thing I remind in particular is the new range of LEDs available - for some years already - and the changes that go with them. It is possible to design the properties of your lights - its spectral power distribution SPD - at very narrower wavelength bands. What does it mean? It means that you can really shape the gamut of your display or light installation, this in term of triangle shape in the color space of your choice. But being able to define a larger, wider color gamut on a sketch is not or should not be the only goal. We also have to think of the internal color space distribution, after all the light source we are most of the time in contact - the sun - has a very different SPD. The good side of it is the door open for us color scientists to continue exploring these new spaces.

It was good to see how my field of studies during my PhD - multi-spectral color reproduction, multi-colorant printing - has evolved. How multi-ink printing systems that were semi-experimental some years ago are now the basis of further experimentation. Further more it always a pleasure to hear someone telling you "I have read your thesis" when they see your name and your face for the first time.

Color science for beginners

I’m a color and imaging scientist who does photography, but sometimes I’m a photographer who does color and imaging research. Depending of the moment and the project one or the other will be predominant.

The practise of photography is always interesting to remind how the light is captured, how images are made. Know the acquisition process in details - light condition, lens used, subject or content - will always help when it is time to work on the images - be it for displaying the resulting images or for extracting automatically information from them.

These few lines are only a glimpse of what color science is. In my many attempts to explain what a color scientist does I came up with this little definition: a color scientist deals with light, its acquisition, preservation and reproduction, of course he also works with images. The term “color” refer to the visible spectrum - a color scientist is a multispectral imaging scientist with limited spectral boundaries - and by adding the word “visible” - visible to the human eye of course - we just extended the range of possible activities such as studying how a human eye does function, how do we perceive light signals, read images. From physics we come to philosophy.

Engineering projects which involve to work with images are often straightforward: you have an image, you need to detect some information, you use a define metric and it is done - almost of course. A color imaging project which involves art, artists and their work is different. Artists and scientists do not speak the same language, they may use the same tools but with different guidelines for sure... But that’s where the fun comes in.

Evening talk in ARTsLab UNM

First day of the scientific program of the 21th Color Imaging Conference and this year it's taking place in Albuquerque, NM. A very funny name to pronouce in french. But enought with the jokes and back to the serious business. Being involved in color science and immersive display I try to follow what people are doing in both fields all over the world. And going to conferences is always a good excuse to knock on the door of the local lab or research department. So this year I contacted some weeks in advance Jane Crayton which I did meet at the Imersa event in Denver three years ago.

After some e-mails exchanged it was planned for me to give a talk entilted "Color Science for Immersive Displays" at the ARTsLab. The ARTsLab (Arts, Research, Technology and Science Laborator and check the link below) is a nice research lab where people from various fields can meet and colaborate, and if you have read the lines above it may involved immersive display... One of their permanent installation is a digital dome of 6 to 7m (?) and a studio which can be used for various tasks.

I wish more people could have attended the talk, but quality is better than quantity. And I was served. The pre-meeting before the talk at a local restaurant was delicious and I could see that some people take their coffee seriously. Hoping to see again the already known contact and newly made here or there in the future.

Some links:
- ARTsLab
- Color Imaging Conference
- Imersa

Color Imaging Conference, first day and Short Course day

It is the third time that I'm able to join the Color Imaging Conference (CIC) after Los Angeles, CA last year and San Antonio, TX in 2010. This time I attend it without article, the one we submitted wasn't exactly finished and did not deserve to be accepted. It is always good to have your paper rejected from a good conference, it only pushes you to improve your work and you end up publishing later a better article. And enough of stating the obvious.

So this time I joined the conference as co-chair on the short course program, or short course session, I never know... Anyway this conference day offers - not for free - a panel of courses given by experts from academia or industry. As co-chair we had, based on last year program, to propose new courses and select submitted courses, they should reflect the latest development in a field and/or give an overview of a given topic (such as multi-spectral imaging or gamut mapping). Interesting and important to me, the courses are also showing connections between research and industry, basic and applied research.

I had the chance to attend three courses: "Normal and Defective Color Vision: from Theory to Simulation" given by Caterina Ripamonti from UCL Institute of Ophtalmology, "Color Grading and Color Management for Motion Pictures" given by Stefan Luka from Walt Disney Animation Studios, and Peter Postma from FilmLight and "What Color is 3D?" given by Matt Cowan from RealD.

The first course was very interesting, because before going to the point of simulating how people with defective color vision see color, state of the art was presented. But more important it shows how color and vision are treated depending of your field of study or depending of your application and which assumptions you are stating to build up your theories and explanations (e.g. which functions are used to approximate how a signal is captured by the eye). We are the border of physiology and computer color science.

The two other courses were related. And the instructors from the color management for motion picture joined the color and 3D lecture after giving their lecture, which ends up with an interesting discussion. A nice aspect of color science in the field of motion picture is the very applied nature of it: how do you capture light, how to process it, how to you compose, create with the various available tools and how do you reproduce and display your work.

And I end up having diner with "la crème de la crème" of color scientists based in UK, Australia, Spain and Germany. Fun fact, none of us four are working in our respective country (whatever it means). As usual, the minimum number of language talked per person was 2.4 . Take that narrow minded and obsessed with boundaries people.