The Mostly Color Channel

Robots in your eyes

2013-06-18T11:42:00.000-07:00

Retinal vein occlusion from glaucoma is only one of several diseases that can decrease the oxygen supply to the retina: Like every tissue of our body the retina needs oxygen. An insufficient supply can cause blindness, sometimes within mere hours. In order to make a fast and correct diagnosis, physicians need to be able to assess oxygen levels within the eye. However, the currently available tools are not very sensitive. Researchers of the multi-scale robotics lab at ETH Zürich have now developed a micro-robot that can measure the retina’s oxygen supply.

News article with link to the paper: Oxygen-sensing microrobots.

Shape Description Experiment: Comments and Discussion

2013-06-14T11:02:00.000-07:00

This is a follow-up post to the Shape Description Experiment to allow reader comments and questions. Thanks.

Shape Description Experiment

2013-06-14T10:59:00.000-07:00

It looks like your browser doesn't support data objects. Click here to go directly to included content. If you have comments or questions about this experiment: Please post them here.

Photography or photographs

2013-06-13T17:03:00.000-07:00

Tuesday I attended an interesting seminar organized by Joyce Farrell at The Stanford Center for Image Systems Engineering (SCIEN). The presenter was
David Cardinal, professional photographer, technologist and tech journalist who talked about Photography: The Big Picture — Current innovations in cameras, sensors and optics.

To cut a long story short,

DSLR systems will be replaced by mirror-less systems, which deliver almost the same image quality for the same cost but are an order of magnitude lighter
point-and-shoot cameras will disappear, because there is no need to carry around a second gadget if it brings no value added over a smart phone (the user interface still needs some work)
phone cameras will become even better with plenoptic array sensors etc., like the one by Pelican Imaging

An interesting factoid for those in the storage industry is that according to an IDC report cited by David Cardinal, in 2011, people took a total number of digital photographs requiring 7 ZB of storage (a zettabyte is 2⁷⁰ bytes). All those photographs could not end up on social networks, because even if for example with Flickr you get 1 TB of free storage, with the typical American broadband connection it would take 6 months to upload that terabyte of images.

David Cardinal mused that maybe people are no longer interested in photographs, but rather in photography. By that he means that people are just interested in the act of taking a photograph, not in sharing or viewing the resulting image. Therefore, he speculated the only time an image is viewed might be the preview flashed just after pressing the release button.

Is that so? According to Cisco's forecast, globally, Internet traffic will reach 12 GB per capita in 2017, up from 5 GB per capita in 2012. For photographers, these are not big numbers when one considers that a large portion of the Internet traffic consists of streamed movies and to a minor degree teleconferences (globally, total Internet video traffic (business and consumer, combined) will be 67% of all Internet traffic in 2017, up from 52% in 2012).

However, we might not remain stuck with the current miserable broadband service for long, and receive fiber services like the inhabitants of Seoul, Tokyo, Osaka, etc. do get. In fact, just a kilometer from here, Stanford's housing area is already on Google Fiber, and other places will soon be receiving Google Fiber, like Kansas City and others around it, Austin, and Provo (in Palo Alto we have fiber in the street, but it is dark and there is nothing in the underground pipe from the curb to my network interface). According to Cisco, globally, the average broadband speed will grow 3.5-fold from 2012 to 2017, from 11.3 Mbps to 39 Mbps (reality check: currently our 6 Mbps down and 1 Mbps up, $48/month, VDSL service delivers 5.76 Mbps down and 0.94 Mbps up; 1 km west, our residential neighbors at Stanford get 151.68 Mbps down and 92.79 Mbps up—free beta Google Fiber). In summary, there is reason to be optimistic.

Should Flickr plan to open a 20 ZB storage farm by 2017 in case people will be interested in photographs instead of photography? Probably not. The limit is not the technology but the humans on either end. We cannot enjoy 20 ZB of photographs. Just ask your grand-parents about the torture of having had to endure the slide-shows of their uncle's vacation.

The path to the answer to David Cardinal's question about photography vs. photographs is tortuous and arduous, at least it was for me.

In spring 1996, HP's storage division in Colorado started manufacturing CD-ROM drives for writable media. To create a market, the PC division decided to equip its new consumer PC line with the drives. The question was what could be the killer-app, and they went to HP Labs for help, because Quicken files would never justify an entire CD-ROM.

At that time my assignment was to work on a web site to showcase a new image format called FlashPix (see image above, click on it to see it at full resolution; a GIF version of the demo is still here). The folder Web Album at the bottom center of the desktop contained the demo I gave the CD-ROM people from Colorado.

In February 1991 I had a dinner with Canon's president Dr. Yamaji, where we strategized over the transition from AgX photography to digital. At that time, Canon had the $800 Q-PIC for consumers (really a camcorder for still video images), and a $28,000 professional DSLR. By considering the product release charts of both Canon and its suppliers, we figured that it would be 2001 until digital could replace AgX in both quality and price. For the time in-between we decided to promote Kodak's Photo-CD solution as a hybrid analog-to-digital bridge.

The people at Kodak told us the average American family keeps their images in a shoe box, with the average number of photographs being 10,000. By looking at the evolution curve of disk drives, which at the time was twice as steep than Moore's law for micro-processors, we figured that the digital family would accumulate an order of magnitude more photographs, namely hundreds of thousands, because the effort and cost per photograph would be so much lower in digital.

As in 1996 I was assembling collections of a few thousand photographs for the FlashPix project, it quickly became clear that images on a disk are much more cumbersome to browse and organize than prints in a shoe box. I tried several commercial asset management programs, but they were too slow on my low-end PC.

I ended up implementing a MySQL database and maintain a number of properties for each image, like keywords, rendering intent prediction, sharpening, special effects, complexity, size, copyrights, etc. Unfortunately it turned out it was very tedious to annotate the images, and it was also very difficult.

Indexing entails categorization, which is a difficult cognitive task, requiring a high degree of specialization. What makes this worse is that the categorization changes in time as iconography evolves. Categorization has a scaling problem: a typical consumer album in 1996 required more than 500 keywords, which are hard to manage. Hierarchical keywords are too difficult for untrained people and taxonomies (e.g., decimal classification system) are too bulky. We proposed a metaphor based on heaping the images in baskets on a desktop:

The labels on the baskets were sets of properties we called tickets, represented as icons that could be dragged and dropped on the baskets. The task was now manageable, but nothing that could be used by consumers.

In a family there typically was a so-called photo-chronicler who would go through the shoe box and compile a photo-album. Photographs by themselves are just information: to become valuable they have to tell a story in the form of a photo-album.

The applet on the right side was running in a browser and would interface to the content on the MySQL database running on the public HP-UX server under my desk. The idea was to reduce the work by allowing any family member who would have time to fill in some of the data: we replaced the model of the mother photo-chronicler with a collaborative effort involving the whole family, especially the grand-parents, who typically have more time.

Collaborative annotation introduces a new problem, namely that each individual has their own categorization system. As described in Appendix II of HPL-96-99, there is a mathematical theory that provides a solution to this problem. An A-construct in mathematics is very similar to an ontology in computer science. The solution is to create ontology fragments for each contributor and then map them into each other leveraging the general structure theory.

Unexpectedly I received a Grassroots Grant, which allowed me to hire a student to rig up an interface to Stanford's Ontolingua system. As a difficult example we took photographs from a mixed-race and mixed-religion wedding (a small sample of the images is here).

We wrote up a conference paper (a free preprint is available here) in a couple of nights, because that was it. A senior manager had determined that nobody would ever have more than 25 digital photographs. The manager insisted that when people would take new pictures, they would delete old pictures so that only the best 25 photographs survive. That was it and the project was killed.

In a way, David Cardinal's photography would be an extreme form of this assertion, where only the last photograph survives, and that only for an instant.

In my view, people are too fond of their memories to just toss them. The future will not be a pile of 20 ZB in pixels. Value is only where a story can be told, and our job is that of creating the tools making storytelling easy.

In retrospect, my mistake in 1996 was to do the annotation as a separate workflow step to be performed after triage. Today the better approach would be to use voice input to annotate the photographs while they are been taken. Today, the metadata is just the GPS coordinates, the time, and the other EXIF metadata. How about having Siri asking the photographer "I see five people in the image you just took, who are they?" "Is this still a picture of the wedding?" etc. Easier and more accurate than doing face recognition post factum. Last but not least, we have the image processing algorithms to let Siri exclaim "Are sure you want me to upload this photograph, I think it is lousy!"

I am game for uploading my share of 4 GB in photographic stories when 2017 comes around!

White House tackles trolls

2013-06-12T11:15:00.000-07:00

On June 4 the White House issued a fact sheet that laid out a framework for five recommended executive actions and seven legislative recommendations for both branches of government to address as a means to tackle "patent trolls." For example, the Patent and Trademark Office will draft a proposal to require patent applicants and owners to "regularly update ownership information" as a means of protecting against the creation of shell companies for hiding abusive litigants. Further, it will permit more discretion in awarding fees to prevailing parties in patent cases, providing district courts with more discretion to award attorney’s fees as a sanction for abusive court filings. It also calls on Congress to craft similar legislative language.

Link: Fact Sheet: White House Task Force on High-Tech Patent Issues

The power of crowd sourcing

2013-06-10T11:43:00.000-07:00

This morning on the local radio in the transmission Morning Edition there was a short piece on the new NSA data farm in Utah, which is supposed to go on-line this September. The piece stated that the data farm will store 5 zettabytes, and the old data farm in Virginia, which will remain on-line, has about 2/3 of the capacity.

These 8 zettabytes are contributed by us aliens, i.e. non citizens: this makes it crowd sourced data. How does this compare to the data that the best and brightest scientists in the world can create? At CERN, the CERN Data Centre has recorded over 100 petabytes of physics data over the last 20 years; collisions in the Large Hadron Collider (LHC) generated about 75 petabytes of this data in the past three years; the bulk of the data (about 88 petabytes) is archived on tape using the CERN Advanced Storage system (CASTOR) and the rest (13 petabytes) is stored on the EOS disk pool system — a system optimized for fast analysis access by many concurrent users. For the EOS system, the data are stored on over 17,000 disks attached to 800 disk servers; these disk-based systems are replicated automatically after hard-disk failures and a scalable namespace enables fast concurrent access to millions of individual files.

A zettabyte is 2⁷⁰ bytes and a petabyte is a paltry 2⁵⁰ bytes, indicating that crowd sourcing can yield 5 orders of magnitude more data than the best scientists can. And while the scientists use the most powerful particle smasher ever built by human kind, the crowd just uses their fingers on plain old keyboards.

The more mind-boggling data point is that at some point the NSA may want to synchronize the data in the two farms. To get an idea of the required bandwidth, consider that backing up a 1 terabyte (2⁴⁰ bytes) solid state disk to a top-of-the-line external disk over a FireWire 800 connection takes 5:39:39 hours…

Servers at the CERN Data Centre collected 75 petabytes of LHC data in the last three years, bringing the total recorded physics data to over 100 petabytes (Image: CERN)

Why color naming

2013-06-07T12:08:00.000-07:00

Mid June 1993 I was strolling along the Duna river in Szentendre with Antal Nemcsics and Lucia Ronchi. We stopped, looking across the river, while Nemcsics was explaining his Dynamic Color theory. Then he turned around and with a broad sweep of his arm he referred to the cityscape stating "it has just been all repainted in its original colors; is it not beautiful how all these yellows from the local clays harmonize?" He then started calling out the names for the yellows and explained how the restoration was based on the sequence of the color names.

When I interjected that color names are arbitrary conventions between painters, and sequences in a perceptually uniform color space might be better, he countered that the color names were not arbitrary but based on solid psychophysics. He answered my question on how the 15 students typically recruited for psychophysical experiments could define something so complex as the names of colors, with the bold statement that for many years all his students had to contribute their data and his Coloroid system was based on the outcome of over 80,000 experiments. Wow, big data!

I had to turn around to the Duna river and take a deep breath. That instant in Szentendre remained deeply impressed in my memory, and I visualized the color name regions of varying volume in the Coloroid space.

A decade later, when I was working on the readability problem of colored text on a colored background, I first implemented an algorithm based on distances in CIELAB. While the solution worked from an engineering point of view, it was not entirely satisfying, because a fixed distance in the entire CIELAB space did not reflect the reality of readability for the various color combinations.

Szentendre came to mind and I decided to try out a different implementation based on lexical distances. Implementing the Coloroid system was not a piece of cake, because the calculations are numerically instable and not all the details of the space are published. Also, if the color names in the Coloroid atlas are adequate for urbanistic applications, some extensions are required to achieve a bullet-proof application for automatic document publishing.

I presented the result at the 2005 AIC meeting in Granada, but I must admit that not many people stopped by at my poster, although it resulted in a collaboration with Silvia Zuffi on the CIELAB based implementation.

Since the color naming solution was going into a product, a patent application was filed, but very reluctantly and with much hesitation. Indeed, color naming and color categorization were very controversial.

Suddenly, in the last few days everything has changed. We now know experimentally that at the quantum level time does not really exists as we perceive it. This new twist on entanglement is one of the tenets for Federico Faggin's new proposal for the concept of awareness. In one arm of the entanglement we have Kirsty L. Spalding, who after a decade of very difficult work studying the hippocampus of people exposed to the fallout of nuclear bomb tests was able to prove experimentally the physiological existence of a locus for categorization. In the other arm we have patent 8,456,694, which thanks to this entanglement is made rock solid.

Proofing a page for color discriminability problems based on color names

2013-06-06T18:25:00.000-07:00

Now that there is a physiological basis for color categorization, we can ask ourselves what this is good for. We cannot eat it, but it might have considerable commercial value in United States Patent 8,456,694 issued two days ago on June 4, 2013. I am not a lawyer, but it appears that if you take two colors, determine their names, and then do anything with it, you might have to license this patent (but you can still keep your hippocampus ☺).

In large American corporations, when a new CEO start their new position, they often begin by putting their mark on the company's branding. They remodel their office and maybe even the HQ entrance, tweak the logo, design a new font, change the corporate palette, etc. These endeavors cost millions of dollars, but big corporations can afford it, especially when as a consequence other big corporations get motivated by the new branding to buy more widgets of the new CEO's company.

The only pity is that often this means that entire forests are wasted when the company has to reprint all its marketing collaterals. Around 2000, my employer at the time had a big warehouse in Campbell with product brochures, but fortunately our manager had been able to convince the company to deploy a document management system and print the marketing collaterals on demand, just when they were needed.

The hard problem came when a year later the CEO decided to change the color palette. Although all brochure chunks were stored digitally, when a brochure was produced by combining chunks with the old palette and chunks with the new palette, the resulting brochure looked inconsistent.

Colleagues Hui Chao and Xiaofan Lin quickly wrote code that could perform a wide range of graphical changes to the collaterals in the repository, and this writer wrote a few lines of code that would replace an old palette color with the perceptually nearest color in the new palette. Unfortunately, already the first test run demonstrated that this was a hack that did not work in practice. For example, many chicklets ended up having bright green text on orange background, something chromatically challenged people with color vision deficiencies could not read.

The solution that worked was to use a model to compute the names of the foreground and background colors, then change one of them to the nearest color in the new palette that was at least to color name categories away from the other color. This solution ended up being very good in practice and we wrote very efficient code that could process a large repository in a very short time.

I guess a sign of good engineering is to have the intuition for an unexpected solution before the scientists have worked out all the facts, …and we did not need nuclear bomb explosions.

Physiology of color categorization

2013-06-06T15:49:00.000-07:00

Up to today there have been quite a few people writing off color naming and categorization as unserious hogwash. As of today, we know of a possible physiological basis, giving us a little more credibility.

In fact, now we know that neurogenesis it taking place in the hippocampus of adult humans. Fresh adult neurons have a specific function facilitating cognitive plasticity in the hippocampus—for example, in helping the brain distinguish between things that belong to the same category, or comparing new information to what it has already learned from experience. The ability to distinguish between vermilion and pink, yet still identify both as flamingo colors, is one example of this type of task in humans.

Kirsty L. Spalding et al. have found that a large subpopulation of hippocampal neurons constituting one-third of the neurons is subject to exchange. In adult humans, 700 new neurons are added in each hippocampus per day, corresponding to an annual turnover of 1.75% of the neurons within the renewing fraction, with a modest decline during aging. They conclude that neurons are generated throughout adulthood and that the rates are comparable in middle-aged humans and mice, suggesting that adult hippocampal neurogenesis may contribute to human brain function.

Reference: Dynamics of Hippocampal Neurogenesis in Adult Humans, Kirsty L. Spalding, Olaf Bergmann, Kanar Alkass, Samuel Bernard, Mehran Salehpour, Hagen B. Huttner, Emil Boström, Isabelle Westerlund, Céline Vial, Bruce A. Buchholz, Göran Possnert, Deborah C. Mash, Henrik Druid, Jonas Frisén: Dynamics of Hippocampal Neurogenesis in Adult Humans. Cell, Volume 153, Issue 6, 1219-1227, 6 June 2013.

Time is not instantaneous

2013-05-22T14:49:00.000-07:00

Science Now today reports on a transitive photon entanglement experiment by Eli Megidish, Hagai Eisenberg, and colleagues at the Hebrew University of Jerusalem in which they show that two photons can be entangled even when they do not exist at the same time. Entanglement is explained by the conservation of energy, and their experiment suggests that this conservation does not have to be in an instant point.

They first create a pair of entangled photons 1 and 2, then they produce a second pair 3 and 4. Then they perform a "projective measurement" on photons 2 and 3, which entangles them. The entanglement property (polarization) of photon 1 is measured, which destroys it. When the entanglement 2, 3 is created after 1 has been measured, 1 and 4 have never coexisted at the same time as an entangled pair. By later measuring 4, the experiment shows that 1 and 4 are entangled.

In the middle, the article states correctly, that entanglement cannot be used to transmit information faster than the speed of light, but in the last paragraph this fact is contradicted. In reality, entanglement can be used to determine if a cipher has been read, but it cannot be used to transmit ciphers.

Link to the article: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

HB-SIA

2013-04-27T18:09:00.000-07:00

Two weeks ago, Switzerland started its new international tourism campaign, projecting a quaint image invented by Romantic writers like Friedrich Schiller and Johanna Spyri, with a few chaps from the Outback fighting in a Schwingen match. This suits well with the political majority party, who would like to place a cheese cloche over the country so it can live in a bubble.

Meanwhile, the Swiss fret over the 2050 energy package, ratified 25 May 2011, after Fukushima and the decision to exit nuclear energy generation. The slogan is that of the 2000-Watt Society, in which each person does not use more than 2000 W per day (today's average is 6000 W) and emits less than 1 Ton of CO₂ per annum.

Such goals require the thought leadership of visionaries and effective demonstrators. Solar Impulse has been one of the best demonstrators. For example, in May 2012 it flew from Payerne across the Mediterranean to Rabat and Quarzazate, convincing the Moroccans that solar energy is the way of the future, supporting the plan by King Mohammed VI to construct the world’s largest thermo-solar power plant in Ouarzazate.

The visionaries behind Solar Impulse are Bertrand Piccard and André Borschberg, along with their sponsors and their big team.

The numbers of Solar Impulse are quite impressive: with a wingspan of 63.40 m it is the size of an Airbus A340 or a 747, but it weighs only 1,600 Kg, just a little more than a Prius. Its range is infinite, because it can fly perpetually, since it produces much more electricity than it consumes, just as the Swiss hope to do with their houses.

Currently Solar Impulse is in Hangar 2 at Moffett Federal Airfield at Ames Research Center, getting ready for the next mission.

Although the airplane can fly perpetually, in their 2015 flight around the world with the second model, license HB-SIB, Bertrand Piccard and André Borschberg will take turns every 5 days, because that is how long a trained human can stay awake and pilot, and also sit with very limited motion on the pilot seat/toilet combo:

On the first of May, Bertrand Piccard and André Borschberg will take off from Moffett Field at a speed of 44 km/h and fly their Across America mission, which will take them to Phoenix, Dallas, Saint Louis or Atlanta, Washington D.C., and finally JFK in New York City.

If you happen to look up and see a jumbo with license HB-SIA soaring silently at a speed of 70 km/h, think what you can do to give back more energy than you consume, so your total usage (think at those servers farms delivering your contents) is below 2000 W per day. In the case of the Solar Impulse, its 11,628 SunPower solar cells have an efficiency of 23% and drive the four brushless sensorless electric engines in addition of charging the batteries for when there is no sunlight.

Color naming 65,274,705,768 pixels

2013-04-16T20:11:00.000-07:00

Where slide 6 is an approximate visualization of the spatial extent of the data analyzed.

Color naming 65,274,705,768 pixels from nmoroney

Alpine Internet Speeds

2013-04-15T06:23:00.000-07:00

The Swiss Federal Office of Communications has published a map of telecommunications in Switzerland. The map can show television availability, upload and download speeds, connection types, and the number of providers, all at a resolution of 250 meters. The publication also provides a guide to broadband expansion projects taking place in Switzerland. The goal of the publication is to help plan broadband access projects and to help users make smart decisions regarding telecommunications.

Link to the tool: broadband map (in German, French and Italian)

Scaling body size fluctuation

2013-04-15T05:42:00.000-07:00

Flocks of birds, schools of fish, and groups of any other living organisms might have a mathematical function in common. Studying aquatic microorganisms, Andrea Giometto, a researcher EPFL and Eawag, showed that for each species he studied, body sizes were distributed according to the same mathematical expression, where the only unknown is the average size of the species in an ecosystem.

Taken together, these observations of size distributions within a species and within all the species in a given ecological community have interesting implications. If in an ecosystem several species begin to converge around the same size, a balancing force will kick in to restore the power-law distribution, either by acting on the abundance or size of each species.

Finding power-laws and using them to describe complex systems already has a successful track record. “In physics, the observation that systems followed power-laws was instrumental in understanding phase transitions. We believe that power-laws can be similarly helpful to gain a deeper understanding of how systems of living matter work,” says Giometto, a physicist, who is seeking to apply methods from his field to understand biological ecosystems.

Link to the paper: Scaling body size fluctuations

Where is the sun?

2013-04-07T15:23:00.000-07:00

When we take architectural pictures, we want to have the sun shining from the side, because this accentuates the edges. In the old days, this meant a shoot took two days, one to visit the sites of the buildings of interest to determine the best time, and a second day to do the actual shoots in a tour taking us to each building at the best time.

Today this is much easier. We can use an online tool like SunCalc to determine the best time.

In the box at the top left you enter the shoot location, then on the horizontal time scale you simply drag the orange dot. On the map, the thick orange segment indicates the sunlight direction. Just move the orange dot on the slider until the segment hits the façade more or less perpendicularly. You can enter the data into a spreadsheet, which you sort by the time, to get your itinerary.

By they way, the thin orange curve is the current sun trajectory, and the yellow area around is the variation of sun trajectories during the year. The closer a point is to the center, the higher is the sun above the horizon. The colors on the time slider above show sunlight coverage during the day.

Color language

2013-03-31T16:58:00.000-07:00

Yesterday we received in the mail this year's first issue of the Atti della Fondazione Giorgio Ronchi (volume LXVIII). On pages 97–106 we found a paper by Lucia Ronchi with the intriguing title Familiarizing with color language I — Evolution and written language. This paper was instigated by the author's reading of Carole Biggam's recent book Semantics of Colour Vision.

Prof. Ronchi compares the frequency and category of color terms in a number of books in Italian, from the an early Psalterium through Dante to contemporary books. The work was accomplished by actually reading the texts and analyzing the color terms in reference to the surrounding text; a more detailed study is promised to appear in a second paper.

This detailed analysis of a few texts is rare in these days, where we tend to study large corpora using big data analytics, as we did for example in the post on which color synonym should I use?

Not having read Biggam's book, the article is in part a little obscure. For example, in the abstract we are given the expectation to read about the relation of studying color terms (linguistics) vs. color categories (cognition), but this is used only intrinsically. Also, we are promised a comparison between color terms and categories in the written and oral languages, but the article covers only the former.

Using Exchange process mailboxes with Java

2013-02-14T14:01:00.000-08:00

In a world where servers are under constant attack, the wise will use the few facilities that can be easily hardened in a firewall and with defensive programming, like servlets. Sometimes it is useful to have something more simple than a web service, such as an email service. For example, you could take a picture with your mobile device and mail it to mostlycolor for a consultation by an automated color advisor.

It is easy to find the information to quickly code up an email client using the JavaMail API and the JavaBeans Activation Framework. Suppose your email is martin.muster@mostlycolor.ch with password !@#$% and your host is mailhub.mostlycolor.ch. You the access your mailbox with the simple statement

store.connect ("mailhub.mostlycolor.ch", "martin.muster@mostlycolor.ch", "!@#$%");

In practice, you do not want to use your mailbox for an automated service, but you want to use a so-called process mailbox on your Exchange server, say color.advisor@mostlycolor.ch. This seems obvious, but I was not able to formulate the correct query to find out how to access a process mailbox. Here is what I found out by trial and error.

Suppose your domain is americas and your login name is musterm. The connect statement then becomes

store.connect ("mailhub.mostlycolor.ch", "americas\\musterm\\color.advisor@mostlycolor.ch", "!@#$%");

Pretty simple once you know the syntax!

New SPIE open access program

2013-02-12T11:30:00.000-08:00

As of January 2013, all new articles published in SPIE journals for which authors pay voluntary page charges are open access immediately on the SPIE Digital Library. SPIE asks journal authors (and their employers or other funders of their research) to provide such support to enable SPIE to hold down subscription prices and maximize access to the research published in SPIE journals. Many authors and institutions provide this support and will now obtain open access for their articles by doing so.

Increasingly, employers and research funders require authors to publish their articles with open access and authors want to do so in order to expand the reach of their research. SPIE provides the benefit of immediate open access for all articles for which voluntary page charges are paid. In these cases, authors retain copyright and SPIE licenses these articles under the Creative Commons Attribution license (CC-BY 3.0).

SPIE recognizes that researchers have modest funds to cover publication expenses. The voluntary page charges will continue to be low: $100 per published two-column page (for journals with both print and online formats) and $60 per published one-column page (for journals with an online format only).

For more information see http://spie.org/x85022.xml

from apprentice to master

2012-12-12T14:13:00.000-08:00

When I grew up on the western edge of Lugano, life in the old country was not very mobile and people tended to spend their life at audible distance from the church bells they heard at birth. The most exotic person you could come across was that wiry old man in a tattered white suit hiking in the woods of Collina d'Oro that was Hermann Hesse, often carrying a drafting book and a box of water colors, totally absorbed in his thoughts.

With this, when Ravi Shankar came to town for a concert sponsored by Migros, it was like a little prince coming from an other planet. Indeed, he and his daughter were wearing traditional Indian clothing, something that had never been seen before on the streets of Lugano. I had the chance to spend a full day and an evening chatting with him, while conducting an interview for the youth radio and helping setting up the recording equipment for the concert.

I was amazed by the difference in personality between him and his daughter. The latter was distant and exotic, but Ravi Shankar was immediate and approachable. It was easy to talk casually with him. I had never seen a sitar before and started to talk with him about the complexity of the instrument. Since he was classically educated, I asked him how long it had taken him to become a master, compared to the piano or the violin. He countered he was not a master at all. When I noted his total command of the sitar and how he appeared to be one with it—even citing Jimi Hendrix and his electric guitar—he rebutted that he was just an apprentice. He continued that the sitar is an instrument that takes a whole life to learn to play, and it is only after reincarnation that one can play it as a master. He pointed out, that when performing on a complex instrument, total mental concentration was necessary and mastery of the sitar takes two lifetimes.

During the concert, I was at the left side of the first row and soon noticed that he was not only in constant musical contact with the other players, but he was also conversing with me through his eyes. Indeed, his protocol was to fixate a member in the audience he thought had an interesting posture, then fixate me, return to the first person to guide my gaze, and when I followed his gaze and looked at that person, he acknowledged with the hint of a smile. While Herman Hesse was totally absorbed in his thoughts, Ravi Shakar was involved concomitantly in three conversations—with the sitar, the orchestra, and the audience—meaning he had full awareness of his surrounding while he was also fully absorbed in the music.

Yesterday Ravi Shankar reached the end of his apprenticeship and today—12/12/12—he is a master sitar player.

Extending the printer gamut upwards

2012-11-14T11:26:00.000-08:00

Full color printing started with cyan, magenta, and yellow. Then black was added to extend the gamut down in the shadows. Later spot colors were added to make the gamut wider (Hexachrome, Indichrome, etc.). Now Romain Rossier & Roger David Hersch are adding light fluorescent magenta and yellow to extend the gamut up in the light colors. They are presenting their work at the CIC 20^th Conference in Hollywood in the Friday afternoon session on Printing chaired by Jan Allebach. Of course, the slides are limited by the projector's gamut, so you need to be there and look at the actual prints.

GPU-accelerated Path Rendering

2012-10-22T14:46:00.000-07:00

Last May I wrote about a major breakthrough in path rendering on the GPU by Mark Kilgard. I am happy to report that Mark—together with Jeff Bolz—has been hard at work on the rest necessary for a complete raster image processor (RIP). They have invented a new "Stencil, then Cover" (StC) algorithm in which the stencil step is explicitly decoupled from the subsequent cover step.

In the stencil step, a path's filled or stroked coverage is determined. In the cover step, the conservative geometry intended to test and reset the coverage determinations of the stencil step is rasterized, while shading color samples within the path. They have not only achieved fantastic acceleration, but also full completeness and correctness. Usually, the performance killer is the bottleneck between CPU and GPU, like when transparency is computed in the CPU. Kilgard and Bolz solve their revalidation bottleneck by using a configurable front-end processor in the GPU to transition quickly between the stencil step and the cover step.

For more information, see their paper at SIGGRAPH Asia, a pre-print of which is available at this link: http://developer.nvidia.com/game/gpu-accelerated-path-rendering.

Binarization

2012-10-16T17:21:00.000-07:00

This year I have been working on document information retrieval, which is as far from color as you can imagine. Indeed, business documents are pretty dry binary black and white items, so that the first step—before even doing optical character recognition—is to binarize the document images so we can efficiently work with bitmaps. In the old days binarization was relatively easy, because almost any scanner illumination can easily be compensated when it is not uniform (see US patent 5,901,243).

Today binarization is much harder, because an increased number of documents is imaged with digital cameras, most often of the kind in smart phones. Much work went into extending existing binarization algorithms to text in pictorial images, alas with little success. It turns out that a completely different algorithmic approach is required, as was recently published in the paper

Yan Wang and Chuanjiang He, Binarization method based on evolution equation for document images produced by cameras, Journal of Electronic Imaging 21 (2012), no. 2, 023030

Here is the abstract:

We present an evolution equation-based binarization method for document images produced by cameras. Unlike the existing thresholding techniques, the idea behind our method is that a family of gradually binarized images is obtained by the solution of an evolution partial differential equation, starting with an original image. In our formulation, the evolution is controlled by a global force and a local force, both of which have opposite sign inside and outside the object of interests in the original image. A simple finite difference scheme with a significantly larger time step is used to solve the evolution equation numerically; the desired binarization is typically obtained after only one or two iterations. Experimental results on 122 camera document images show that our method yields good visual quality and OCR performance.

Blue nights

2012-09-20T10:42:00.000-07:00

I usually sleep with open curtains. Fireflies aside, growing up, when I woke up in the middle of the night and looked up, I saw the Milky Way. It was quite a change when as a student I moved into a room in Zürich's Predigergasse that had a gaslight on the corner of the house, just outside my windows. When I woke up in the middle of the night, instead of a black firmament with the twinkling Milky Way, I experienced being bathed in a flickering red light. My insomniac nights changed from black to red.

Our house in Palo Alto features a street light smack in front. At night, monochromatic yellow sodium light shines through the large picture window and paints the house in a warm light, emphasizing the polenta-yellow walls and the golden white oak hardwood floors.

Until yesterday.

The City replaced the sodium lamp with an LED lamp and the floors are now patterned by cold blue reflections, which in turn create eerie light plays on the walls. Instead of averaging and blurring the material structures, the new light analyzes and emphasizes them.

It will take some time getting used to it.

By the way, in 1980 low pressure sodium street lighting became common in the Silicon Valley in support of the Lick Observatory on Mount Hamilton, to reduce light pollution. The Barron Park neighborhood in Palo is dark at night, because the inhabitants keep their porch lights off. Their neighborhood park is named after Cornelis Bol, a Stanford physicist and the inventor of the high-intensity mercury vapor lamp.

Avoidance of plagiarism

2012-09-06T18:47:00.000-07:00

As the center of gravity for scientific research is moving from old locales with longstanding traditions to new geographies with forgotten traditions or which never had them, plagiarism has become a major issue. At times it feels like being in the Wild West.

Sometimes papers are pure copies of previous work. More often, authors have not yet developed a proper hygiene for citing related work. I am always surprised how often authors cite secondary references instead of primary references, a fact I tend to take as laziness and punish with a negative review.

In Volume 6, Issue 1 of the SPIE Journal of Nanophotonics, Editor-in-Chief Akhlesh Lakhtakia has written a very useful editorial on this topic. Follow this link: http://dx.doi.org/10.1117/1.JNP.6.069901.

Firefly

2012-08-24T17:31:00.001-07:00

The firefly plays a special role in Japanese culture. It is called hotaru (蛍, ほたる) and we researchers know it from the expression 蛍雪 (けいせつ), or firefly-writing, which refers to diligence in studying (i.e., continue to study even in such poor light as offered by a firefly). For more wordly people, the firefly is the symbol of passionate love.

At least from the 24 April 1185 battle of Dan-no-ura, where the Genji under Minamoto no Yoshitsune, defeated the Heike (Taira), if not from earlier, it is believed that when soldiers are killed in battle, their souls are transformed into fireflies. Therefore, in Japan the view of hotaru is very sentimental and patriotic.

Today the life of scientists is more peaceful, as researchers are no longer killed like Goethe's Faustus when his grant was up or Giordano Bruno when he came up with the mathematical concept of infinity (see glad not to be on the stake), so we can be cheerful when we see fireflies.

I remember when we moved to Lugano, at the city's border, consisting mostly of untended fields. The place did not even have a name yet, it was just the far end of Besso, or Lugano 3, as the postal system prosaically called it with the introduction of zip codes. As kids we only had to run away from the apartment buildings for a few minutes to be in a completely dark environment devoid of any light pollution. The black sky was dotted with infinite stars, but in summer, towards Cortivallo and the lake of Muzzano, we were immersed in a cloud of fireflies. It was a magic experience.

Of course, today as color scientists we are more interested in the spectrum of the firefly. Entomology teaches us that males and females are anatomically different, with the latter having two lateral light sources and the former three adjacent light sources. This means that we have to measure the sexes independently. How can we achieve that?

In his recent paper in Atti della Fondazione Giorgio Ronchi, volume LXVII (2012), number 3, pages 455–458, Paolo Stefanini reports how he accomplished it.

The males normally cruise above the fields, while the females are hidden in the grass. When the females want to mate, the crawl to the apex of the grass leaves and wait. A males ready to mate flashes his light and a female flashes back, then they go at it. Therefore, Stafanini first measured the males, then he built a male decoy using LEDs. The decoy allowed him to beat the females out of the bushes, so he could measure them too.