This how the researchers worked on the videos, which was no small feat, as mentioned by the researchers in a research paper on the topic. They sorted some 86 million photos by geographic location, then used an automated process to find photos that rallied around the same landmark. Once those images were listed, the photos were then arranged in a chronological order of date and later twisted to create the same perspective to show the changes over time. Lastly, each image was color-corrected to have a same appearance, resulting in uniform time-lapse videos. The videos are not only astonishing, but also are very well lighted. For example, the video show glaciers diminishing, waterfalls developing gradually and skyscrapers springing up, making them useful tools for builders or geologists. The intellectual thought that went into the time-lapses is also interesting, as researchers merged various techniques in warping, stabilization and color normalizing to make it work. Many sequences have over 1,000 images and took around six hours to render on a single computer. The researchers wrote that “This capability is transformative; whereas before it took months or years to create one such time-lapse, we can now almost instantly create thousands of time-lapses covering the most popular places on earth. The challenge now is to find the interesting ones, from all of the public photos in the world. We call this problem time-lapse mining.” The researchers see a much brighter future for these time-lapses videos in the coming years. According to them, nearly 11,000 time-lapses are just the beginning. With more and more public photos that are available online every day, they can be seized and used for time-lapses. Time will also help widen the scale of currently available time-lapses.
“The scale and ubiquity of our mined time-lapses creates a new paradigm for visualizing global changes,” the researchers wrote. “As more photos become available online, mined time-lapses will visualize even longer time periods, showing more drastic changes.” The best part of these time-lapse videos are that even though they are an entertaining form of crowdsourcing, it does not need require the people in the images to do anything but be tourists. Resource : University of Washington
