Have you read the top Pixalytics blogs of 2016?

Artist's rendition of a satellite - paulfleet/123RF Stock Photo

Artist’s rendition of a satellite – paulfleet/123RF Stock Photo

As this is the final blog of the year we’d like to take a look back over the past fifty-two weeks and see which blog’s captured people’s attention, and conversely which did not!

It turns out that seven of the ten most widely viewed blogs of the last year weren’t even written in 2016. Four were written in 2015, and three were written in 2014! The other obvious trend is the interest in the number of satellites in space, which can be seen by the titles of six of the ten most widely read blogs:

We’ve also found these blogs quoted by a variety of other web pages, and the occasional report. It’s always interesting to see where we’re quoted!

The other most read blogs of the year were:

Whilst only three of 2016’s blogs made our top ten, this is partly understandable as they have less time to attract the interest of readers and Google. However, looking at most read blogs of 2016 shows an interest in the growth of the Earth Observation market, Brexit, different types of data and Playboy!

We’ve now completed three years of weekly blogs, and the views on our website have grown steadily. This year has seen a significant increase in viewed pages, which is something we’re delighted to see.

We like our blog to be of interest to our colleagues in remote sensing and Earth observation, although we also touch on issues of interest to the wide space, and small business, communities.

At Pixalytics we believe strongly in education and training in both science and remote sensing, together with supporting early career scientists. As such we have a number of students and scientists working with us during the year, and we always like them to write a blog. Something they’re not always keen on at the start! This year we’ve had pieces on:

Writing a blog each week can be hard work, as Wednesday mornings always seem to come around very quickly. However, we think this work adds value to our business and makes a small contribution to explaining the industry in which we work.

Thanks for reading this year, and we hope we can catch your interest again next year.

We’d like to wish everyone a Happy New Year, and a very successful 2017!

Playboy Magazine & Remote Sensing

Blue Marble image of the Earth taken by the crew of Apollo 17 on Dec. 7 1972. Image Credit: NASA

Blue Marble image of the Earth taken by the crew of Apollo 17 on Dec. 7 1972.
Image Credit: NASA

Are you aware the role Playboy Magazine has had in the remote sensing and image processing industries? Anyone who has read a selection of image processing books or journals will probably recognise the Lena picture as a standard test image. If you don’t know the image, you can find it here. Lena’s history is interesting.

It began in 1973 when Alexander Sawchuk, who was then an assistant professor at the USC Signal and Image Processing Institute, was part of a small team searching for a human face to scan for a colleague’s conference paper. They wanted a glossy image to get a good output dynamic range and during the search someone walked in with the November 1972 issue of Playboy. They used the centrefold image, the Swedish model Lena Söderberg, so they could wrap it around the drum of their scanner. As they only needed a 512 x 512 image, they scanned the top 5.12 inches of the picture, creating a head shot rather than the original full nude centrefold.

From this beginning Lena, often called Lenna as this was the forename used in Playboy, has gone to be one of the most commonly used standard test images. There are a number of theories of why this is the case, including:

  • The image has a good variety of different textual elements, such as light and dark, fuzzy and sharp, detailed and flat.
  • The grayscale version contains all the middle grays.
  • She has a symmetrical face, making any errors easy to see.
  • The image processing community is predominantly male!

Most often the image is used for compression testing, but has also used been used in the analysis of a wide variety of other techniques such as the application of filtering for edge enhancement. Even as recently as three years ago a group of scientists from Singapore shrunk the Lena image down to the width of a human hair as a demonstration of nanotechnology printing.

The wide use of Lena eventually came to the notice of Playboy, after the magazine Optical Engineering put her on their front cover in 1991. The Playboy organisation then tried to assert their copyright, however the genie was out of that bottle given the sheer number of people using it. The following year Optical Engineering reached an agreement with Playboy to continue using the image for scientific research and education. The copyright issues are why we didn’t include the Lena image on the blog, although has been reported that Playboy now overlook the use of the Lena for image processing we decided not to risk it! Playboy did help in the search for Lena in 1997 which enabled her to make a public appearance at the 50th Annual Conference of the Society for Imaging Science in Technology. An article written by Jamie Hutchinson giving a more detailed version of the Lena story can be found here.

What’s interesting about Lena is that despite all the technological advancements in the last forty years, she is still used as a standard testing image. Contrast this with the famous Blue Marble image of the Earth taken around the same time by astronauts aboard Apollo 17. The 1972 Blue Marble is probably the most iconic picture of the Earth, and unlike Lena has inspired numerous later images. For example, NASA used the Terra satellite to produce a detailed true-colour image of the Earth in 2002 and then three years later surpassed it with a new image that had twice as much detail as the original. The latest NASA Blue Marble was issued last year, captured by the US DSCOVR Earth observation satellite.

Standard test images are important, but the image processing community should probably start to think about updating the ones we use. Anyone got any ideas?