Thursday, July 17, 2014

Tic-tac-toe patent 8,770,625 in color

As noted on lines 23 and 24 in column 4 of the printed version of patent 8,770,625,
the U.S. Patent Office procedure discourages the use of color drawings. This makes Fig. 4 a little hard to visualize for the non color scientist (there are no color figures in Wyszecki & Stiles), so here it is in color (right pane):

Figure 4 of US patent 8770625

The invention is relatively simple. The general field is anti-counterfeiting as it applies to packaging. Professional counterfeiters have no problem faking ordinary measures like serial numbers and holograms, so the trick is to embed information that cannot easily be perceived by a counterfeiter, hence is omitted in the facsimile. Fortunately color does not exist in nature, it is just an illusion happening in our minds. Therefore, all we have to do is to create an illusion you can only perceive if you expect it.

As described in patent 8,770,625, a number computed from the—possibly counterfeited—serial number on the package can be encoded positionally in a tic-tac-toe grid. The marking is just above the visual threshold, so the naive counterfeiter will reproduce the same pattern on all packages. The trained inspector can then quickly assert whether an actual positional code corresponds, for example, to the possibly fake serial number.

Patent 8,770,625 is relatively short with just three claims, but reducing it to practice is a little tricky, even when all the steps are disclosed in the patent. The difficult part is to design the tool to determine experimentally the visual thresholds for the print process being used and the light conditions under which the inspections are expected to happen. You need to be skilled in the art.

The above figure is a screen-shot of that tool. To implement it you need to write a spectral color management system with CIE colorimetry to simulate the press on the display and vision colorimetry to model what the actual human visual system perceives. The details of the controls are explained in patent 8,770,625.

Depending on your viewing conditions, the above color version of Fig. 4 might be under the visual threshold. If that is the case, in the figure below we crank up the saliency and decrease the background coverage, so you will see the encoding for sure. If you have aliasing problems, you can click on the figures to display them at the original resolution in which they were created eight years ago, early July 2006 (time flies).

a more salient alternate to figure 4 of US patent 877,625

Wednesday, July 16, 2014

Why peacocks have eyespots on their feathers

"BIRD PARK 8 0189" by Myloismylife - LOKE SENG HON - Own work by uploader - LOKE SENG HON. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons -"BIRD PARK 8 0189" by Loke Seng Hon (Own work) via Wikimedia Commons

Charles Darwin ventured that the magnificent trains on male peacocks, which feature ornamental eyespots called ocelli, evolved because of sexual selection. He speculated that there was a single origin, which sexual selection then enhanced. A new genetic study of peacocks and closely related pheasants found that this trait appears in some birds but not others, which suggests that it independently evolved repeatedly.

Article: Keping Sun, Kelly A. Meiklejohn, Brant C. Faircloth, Travis C. Glenn, Edward L. Braun, and Rebecca T. Kimball: The evolution of peafowl and other taxa with ocelli (eyespots): a phylogenomic approach. Proc. R. Soc. B September 7, 2014 281 1790 20140823; doi:10.1098/rspb.2014.0823 1471-2954

Friday, July 11, 2014

Red and Romantic Rivalry

Viewing another woman in red increases perceptions of sexual receptivity, derogation, and intentions to mate-guard.

Woman worker dressed in red in the Douglas Aircraft Company plant 1942

Research has shown that men perceive women wearing red, relative to other colors, as more attractive and more sexually receptive; women’s perceptions of other women wearing red have scarcely been investigated. Adam D. Pazda, Pavol Prokop and Andrew J. Elliot hypothesized that women would also interpret female red as a sexual receptivity cue, and that this perception would be accompanied by rival derogation and intentions to mate-guard. Experiment 1 demonstrated that women perceive another woman in a red, relative to white, dress as sexually receptive. Experiment 2 demonstrated that women are more likely to derogate the sexual fidelity of a woman in red, relative to white. Experiment 3 revealed that women are more likely to intend to guard their romantic partner from a woman wearing a red, relative to a green, shirt. These results suggest that some color signals are interpreted similarly across sex, albeit with associated reactions that are sex-specific.

Adam D. Pazda, Pavol Prokop, and Andrew J. Elliot: Red and Romantic Rivalry: Viewing Another Woman in Red Increases Perceptions of Sexual Receptivity, Derogation, and Intentions to Mate-Guard. Pers Soc Psychol Bull 0146167214539709, first published on July 11, 2014 doi:10.1177/0146167214539709

Wednesday, July 2, 2014

Venture capital

We used to talk about the Silicon Valley, but nowadays it seems more appropriate to talk about that triad comprising San Francisco, the Peninsula, and San Jose. People prefer to talk about the Bay Area, but that includes too much "regular economy" to define correctly the locus of the current gold rush.

The previous gold rush was about the commercialization of the Internet and was called the .com boom. Today's rush is nicknamed Web 2.0, but it is much less of a technology rush. While .com came after the end of the cold war and the end of research labs spilling redundant scientists and researchers to fill the cubicles of technical entrepreneurs, Web 2.0 is much more about business.

The analogy is with patents. Gold diggers take an old business idea, add the word computer, get a patent, then sue the incumbents for patent infringement and get away with plenty of dollars.

In the real economy, the Web 2.0 entrepreneurs come up with an idea for a service that can be implemented on the Web. Today's various cloud providers make this very cheap and simple. The monetization consists in giving the impression that the service is free. In reality, the customers are used to crowd-source information by coaxing them to provide detailed information about themselves. This information can then be sold to one of the more than a thousand personal information brokers operating in the USA.

Recently, companies have been valued at up to $100 per customer, which is very high. Accordingly, investors are poring billions of dollars into this area. Because this is gambling and speculation, the amount of money is not a good indicator of the real economy here.

I tried to look at a more conventional technology, namely the storage industry. My data is just accumulated from press releases and is not authoritative nor complete, because I have not gathered it systematically. However, here it is:

On the abscissa we have funding dates, categorized by quarters. On the ordinate we have companies related to storage (my apologies for mistakes). Each point is an investment round. The diameter represents the accumulated funding so far of the company. You can click on a ball to see the details.

When there is a long horizontal line of regularly spaced balls of the same diameter, the start-up is not really taking off. When the diameter is rapidly increasing, the company is getting a lot of interest from the investors.

We see that as we move forward in time, many more companies are getting funded and some companies are real winners. This is a good sign, because it means that investors are not just gambling their money on social network companies but also investing in the nut and bold technologies that allow for a healthy sustainable future-oriented economy.

Monday, June 30, 2014

These days the moon is made of cheese

From the remarks by President Obama at University of California-Irvine Commencement Ceremony, Angel Stadium Anaheim, California, June 14, 2014, 12:10 P.M. PDT.

Part of what’s unique about climate change, though, is the nature of some of the opposition to action. It’s pretty rare that you’ll encounter somebody who says the problem you’re trying to solve simply doesn’t exist. When President Kennedy set us on a course for the moon, there were a number of people who made a serious case that it wouldn’t be worth it; it was going to be too expensive, it was going to be too hard, it would take too long. But nobody ignored the science. I don’t remember anybody saying that the moon wasn’t there or that it was made of cheese.

Official transcript of the remarks: The White House Office of the Press Secretary

President Barack Obama

Thursday, June 26, 2014

Appearance of flamingos reloaded

A few years ago we mused on the color appearance of flamingos:

Now Daniel B. Thomas, Kevin J. McGraw, Michael W. Butler, Matthew T. Carrano, Odile Madden and Helen F. James have studied the issue in general for plumed animals and more importantly, over time.

They visually surveyed modern birds for carotenoid-consistent plumage colors. They then used high-performance liquid chromatography and Raman spectroscopy to chemically assess the family-level distribution of plumage carotenoids, confirming their presence in 95 of 236 extant bird families. Using their data for all modern birds, they modeled the evolutionary history of carotenoid-consistent plumage colors on recent supertrees. Results support multiple independent origins of carotenoid plumage pigmentation in 13 orders, including six orders without previous reports of plumage carotenoids. Based on time calibrations from the supertree, the number of avian families displaying plumage carotenoids increased throughout the Cenozoic, and most plumage carotenoid originations occurred after the Miocene Epoch (23 Myr). The earliest origination of plumage carotenoids was reconstructed within Passeriformes, during the Palaeocene Epoch (66–56 Myr), and not at the base of crown-lineage birds.

Link to the paper: Ancient origins and multiple appearances of carotenoid-pigmented feathers in birds

Tuesday, June 24, 2014

Portraits reveal rare disorders

Doctors faced with the tricky task of spotting rare genetic diseases in children may soon be asking parents to email their family photos. A computer program can now learn to identify rare conditions by analysing a face from an ordinary digital photograph. It should even be able to identify unknown genetic disorders if groups of photos in its database share specific facial features.

Read the article in the New Scientist: Computer spots rare diseases in family photos

Friday, June 20, 2014

Staring at computers all day alters your eyes

As a color scientist you already know that you have to position your display and chair combination so that the top bezel is at the same height as your eyes. The reason is so your eyes are not wide open and dry out. You also avoid sticking a personal fan in the display's USB port and tilt the display face slightly down so you cannot see light fixture reflections.

To my surprise, although this is usually explained in the ergonomics booklets shipping with computers, this is not generally known and scientists can still get research grants to study it (The Osaka Study):

The data obtained in the present study suggest that office workers with prolonged VDT (visual display terminal) use, as well as those with an increased frequency of eye strain, have a low MUC5AC (mucin 5AC) concentration in their tears. Furthermore, MUC5AC concentration in the tears of patients with DED (dry eye disease) may be lower than that in individuals without DED.

Citation: Uchino Y, Uchino M, Yokoi N, et al. Alteration of Tear Mucin 5AC in Office Workers Using Visual Display Terminals: The Osaka Study. JAMA Ophthalmol. Published online June 05, 2014. doi:10.1001/jamaophthalmol.2014.1008.

The paper costs $30, but you can read the current JAMA issue for free if you register.

Thursday, June 19, 2014

Friedrich Miescher

James Watson and Francis Crick may be the names most associated with DNA, but many people were involved significantly in the study of DNA. Most famously, British biophysicist and X-ray crystallographer Rosalind Elsie Franklin (25 July 1920 – 16 April 1958) took the X-ray diffraction images of DNA which led to the discovery of the DNA double helix. According to Francis Crick, her data was key to determining the structure to formulate Crick and Watson's 1953 model regarding the structure of DNA.

DNA was first isolated by the Swiss physician Johannes Friedrich Miescher (13 August 1844 – 26 August 1895) who, in 1869, discovered a microscopic substance in the pus of discarded surgical bandages. As it resided in the nuclei of cells, he called it "nuclein." He intuited that the molecule played a role in heredity, but did not believe that a single molecule could lead to a huge variety of individuals and species, says Ralf Dahm, of the Institute of Molecular Biology in Mainz, Germany, who has written about Miescher's work. He says Miescher has kept a low historical profile, in part due to his "introverted" and "insecure" personality.

Earlier this year, CureVac, a company based in Tübingen, Germany, that develops RNA-based vaccines and therapies, won a €2 million prize for innovation from the European Union and announced plans to use some of that money to restore the University of Tübingen lab where Miescher made his discovery. Together with the university, the firm wants to transform the lab, the former kitchen of the old town's medieval castle, into a public exhibition about his work and legacy. (The university now uses the space as a computer room.)

Wednesday, June 18, 2014

Color facsimile flashback

Recently a friend showed me on YouTube a movie called Silicon Valley. The movie mostly introduced characters and their environment, finishing without a conclusion, so I suspect it is an episode from a TV series. The setting is a stereotype of the Web 2.0 Silicon Valley and a good part of the plot took place in a company called Hooli, a mini version of real world Google.

If you live in the Silicon Valley the movie might be boring. However, the technology the main character is supposed to have invented got my attention. It is supposed to be a lossless compression algorithm for audio files that can achieve a compression rate of 1:100. Of course, this is impossible as described in the movie, because on a stypical file the lossless compression rate using the Deflate algorithm (Lempel-Ziv followed by Huffman) is about 1:3. The description in the movie is impossible because there is not that much entropy in typical audio files.

Indeed, the writer forgot a qualifier, such as perceptually or better should have written about listening performance.

On that, my colleagues and I happen to have a couple of patents, namely US 5,883,979 A Method for selecting JPEG quantization tables for low bandwidth applications and US 5,850,484 A Machine for transmitting color images.

U.S. Patent 5,883,979 Method for selecting JPEG quantization tables for low bandwidth applications

Facsimile (fax) is an old technology for transmitting images over phone lines that is probably alien to today's readers. In analog fax, the machine consisted of a metal cylinder on which one would affix the page of a document. On the sender side, a head would shuttle in the fast scan direction and at the end of the cylinder the head would shuttle back while the cylinder rotates by one scan line in the slow direction. During the first shuttle, a photosensor in the head would produce a sound in the phone line each time it encounters a black photosite.

At the receiving end, a similar machine would move synchronously and each time a sound arrives in the phone line, it would produce a spark that would burn a dark spot in the paper.

This process was extremely slow, so it would be used only for dense documents. For text documents one would retype the document on a telex machine, which produces a legally valid copy of the text.

Forty years ago I was using fax all the time. When as a field engineer I had an OS crash I could not figure out, I would print out the core dump as a hexadecimal string and fax it from Zürich to Goleta, where the R&D division was. At the time email was not encrypted and people at any forwarding node could and did read the messages. Furthermore, telex was a European thing that was not commonly used in the USA.

A revolution happened in 1964, when Xerox invented the telecopier, which was based on a digital fax technology. The machine would convert the photosites into zeros and ones and store them in a buffer as a digital string. This string would be compressed before being transmitted. There was a hierarchy of compression algorithms that could use 1-d , 2-d coding schemes or pattern matching, with names like MH (ITU T.4), MR, MMR (T.6) and JBIG (T.85).

Having a digital signal that can be compressed with mathematical algorithms, the transmission time dropped dramatically from an hour to under two minutes per page with a typical 9600 baud modem of the time. A dozen years after the Xerox telecopier, Japanese companies were producing very affordable fax machines that became ubiquitous. In Japan, every household had a fax machine, because you could handwrite kanji text on a sheet of paper and fax it, while typing kanas was rather slow.

In 1994 I joined a team inventing the color fax technology. The international effort took place under the ITU umbrella as T.42. For the color encoding we used CIELAB, because being perceptually uniform it allowed the most compact representation. For the spacial encoding we used JPEG.

Compression methods used in color fax

At that time, digital color imaging was still in its infancy (in Windows 3.1 you could only have 16 device colors by default) and the early inkjet printers were fuzzy, as were the early color scanners of the time. The signal processing researchers on the team applied spacial filters to improve the quality of the images, but this actually made the images look worse because the compression artifacts were being amplified.

Artifacts in color fax text

I had the crazy idea of transforming the sharpening algorithm itself to the cosine domain. There the sharpening function could be expressed as a transformation of the DQT, or the quantization tables for the 64 kernels of the discrete cosine transform. We called this image processing in the compressed domain and essentially it consisted in lying about the DQT. For the JPEG encoding we used DQTs optimized for the input image, while the DQT included in the JPEG image was a transformed DQT including the sharpening. This is the essence of patent US 5,850,484.

Office documents consist of a combination of text and image data or mixed raster content (MRC, see here), so we would segment the document stripe by stripe and compress the foreground for example with JBIG, the mask with MMR and the background with JPEG. The ITU standards were T.44 for MRC and T.43 for JBIG in CIELAB.

Even so, transmitting the test targets (e.g., 4CP01) over a 9600 baud line would take 6 minutes per page, which in 1994 was considered unacceptable. At that time the experience was that when a device transitions from black-and-white to color, the price could be at most 25% more and the performance would have to be the same. We felt that a color fax could not take longer than 2 minutes per page on a 9600 baud connection. We achieved 90 seconds.

This prompted us to investigate perceptually lossy compression. In lossless compression, after decompression we obtain exactly the same data as in the input file. In perceptually lossless compression like JPEG or MPEG-2 Audio Layer III (a.k.a. MP3), after decompression we obtain less data, but we cannot perceive the difference. In other words, we leave out the information we cannot perceive anyway. The cosine transform makes the discretization straightforward.

This is like in color encoding we can transform the images to the CIELAB color space because it is perceptually uniform and one unit corresponds approximatively to a JND (just noticeable difference), so we can discretize from floating point to integer without perceiving a difference.

Staying with color, the next step is to further discretize the colors, so that we can perceive a difference (perceptually lossy), but it does not impair our ability to make correct decisions based on the degraded images. This had led us to color consistency and using color names to compare colors. This is related to cognitive color and categorization.

The analogue for the text in mixed documents is reading efficiency, i.e., our reading performance is not reduced based on reading speed or the ability to ready without errors. This is covered by patent 5,883,979, which I explained in this SPIE paper:

Giordano B. Beretta ; Vasudev Bhaskaran ; Konstantinos Konstantinides and Balas R. Natarajan "Perceptually lossy compression of documents", Proc. SPIE 3016, Human Vision and Electronic Imaging II, 126 (June 3, 1997); doi:10.1117/12.274505;

perceptually lossy compression

This is a long explanation and you cannot do it in a movie, but at least the script writer should have added the qualifier perceptual in the algorithm name and it would all have been more plausible.


If the invention is sufficiently novel that it can become the basis for a plot in a Hollywood movie twenty years later, why was my professional career a failure? As it happens, 1994 was also the time when the Internet became available to the general public and everybody went on email. An email attachment is more convenient than having a separate fax machine, especially in a crammed Japanese house. Also, the Internet was running on fiber to the home (FTTH) instead of the slow copper phone lines of the phone and fax.

Timing is everything.