Hidenori Watanave, an associate professor at Tokyo Metropolitan University, has been exploring a tool created by researchers at Japan's Waseda University that colorizes images using neural networks [2] and posting some of his results to Twitter [1].
Waseda University's online project, called Neural Network-based Automatic Image Colorization [3], was developed by researchers Satoshi Iizuka [4], Edgar Simo-Serra [5] and Hiroshi Ishikawa [6]. Neural networks are computer systems that work in a way that's similar to the human brain. Anyone can use their web-based tool [2] to add color to black-and-white images.
Watanave has used the tool in several projects devoted to preserving and mapping eyewitness testimony from World War II, including an interactive map of the Hiroshima [7] and Nagasaki [8] atomic bombings, and the Battle of Okinawa [9] in 1945. Watanave [10] is also the creator of a similar innovative mapping project [11] that tracks the last moments of the victims of the March 2011 earthquake and tsunami in Japan [12].
@AtomicHeritage [13] @WWIImuseum [14] A-Bomb cloud from Kure, Hiroshima. Automatic colorization by a neural network. pic.twitter.com/LjpcxLOUw0 [15]
— Hidenori Watanave (@hwtnv) December 22, 2016 [16]
Often, however, Watanave experiments with a variety of images, which he then posts to Twitter. Watanave has used the neural network-based technique to colorize a variety of photos from Japan's experience during the Second World War.
米軍機から撮影された沖縄本島爆撃のようす。渡久地と周辺の島から爆煙が上がっている。ニューラルネットワークによる自動色付け。沖縄平和学習アーカイブより。 https://t.co/IcLM5VCIph [17] pic.twitter.com/iXFRjdfDc4 [18]
— Hidenori Watanave (@hwtnv) January 4, 2017 [19]
Image of bombardment on Okinawa filmed from an American military aircraft. Smoke rises from the islands around Toguchi, Okinawa. From the Peace Learning Archive in Okinawa (沖縄平和学習アーカイブ [20]). Colorized by neural network.
1945年2月から3月,日本軍と連合国軍の間で行なわれた「マニラの戦い」で破壊された市街地.ニューラルネットワークによる自動色付け.写真はこちらから. https://t.co/eA8dPdPTR0 [21] pic.twitter.com/qzCWRgsek2 [22]
— Hidenori Watanave (@hwtnv) January 5, 2017 [23]
In February and March 1945, Japanese forces and the Allies fought the Battle of Manila, which destroyed the city. Colorized photo originally from http://www.vintag.es/2016/12/18-rare-vintage-photographs-that-show.html [24]
Many of the colorized photos he posts are ones he collected and curated as part of his projects detailing oral histories of the Hiroshima and Nagasaki bombings.
被爆直後の長崎。破壊された浦上天主堂。ニューラルネットワークによる自動色付け。ナガサキ・アーカイブより。 https://t.co/0JvaERYLpA [25] pic.twitter.com/LdaQLmccmh [26]
— Hidenori Watanave (@hwtnv) January 4, 2017 [27]
Nagasaki immediately after the nuclear blast. A demolished Urakami Cathedral.
被爆直後の広島。紙屋町交差点の北側から南西に向かって。ニューラルネットワークによる自動色付け。ヒロシマ・アーカイブより。 https://t.co/EJcybdeTEw [28] pic.twitter.com/jZlAyIl8pK [29]
— Hidenori Watanave (@hwtnv) January 4, 2017 [30]
Hiroshima immediately after the atomic bombing. Looking southwest from the north side of Kamiya-machi crossing. Photo from the Hiroshima Archive [31].
Not all of Watanave's experiments have to do with the war. Many photos depict scenes from Japanese history over the past century or so.
1975年10月、カリフォルニアのディズニーランドを訪れた昭和天皇。ニューラルネットワークによる自動色付け。 pic.twitter.com/gHIAXJp2en [32]
— Hidenori Watanave (@hwtnv) December 22, 2016 [33]
In October 1975, Emperor Hirohito visits Disneyland in California.
1930年代,別府の海岸で砂風呂を楽しむ女性たち.ニューラルネットワークによる自動色付け. pic.twitter.com/CZZyLGR8am [34]
— Hidenori Watanave (@hwtnv) January 3, 2017 [35]
Women enjoying a hot-sand bath in Beppu sometime in the 1930s.
1908年にArnold Genthe氏が撮影した写真。場所はどこだろうか。ニューラルネットワークによる自動色付け。 pic.twitter.com/Pk4ureVhXc [36]
— Hidenori Watanave (@hwtnv) December 29, 2016 [37]
Photo taken by Arnold Genthe [38] in 1908. It's unclear where in Japan this photo was taken.
And not all of Watanave's colorization experiments have to do with Japan. This interesting photograph provides a window into the Korean War:
朝鮮戦争出兵中の兵士たちを慰問するマリリン・モンロー.1954年撮影.ニューラルネットワークによる自動色付け. pic.twitter.com/SutKWH17cJ [39]
— Hidenori Watanave (@hwtnv) January 3, 2017 [40]
Marilyn Monroe entertains troops deployed in 1954 during the Korean War.
Watanave's Twitter feed can sometimes produce interesting results. Here, a Twitter follower appears to recognize a colorized photo of her own mother taken nearly 50 years ago in Tokyo:
晴れ着に日本髪で初仕事に就く電話交換手の女性たち。昭和45年1月5日、東京都千代田区。ニューラルネットワークによる自動色付け。 pic.twitter.com/vW4stLY1fC [41]
— Hidenori Watanave (@hwtnv) January 1, 2017 [42]
Dressed in their Sunday best and in a traditional Japanese hairstyle, young women enter the workforce [around the time of the annual Coming of Age Day [43]] on January 5, 1970, in Chiyoda Ward, Tokyo.
@hwtnv [44] ありがとうございます。自分の母の若い頃を見るようです。
— ほっぴー@この世界の片隅に (@hoppe714) January 1, 2017 [45]
Thank you for posting this photo. That looks like my mother when she was young.
Technical details of the Waseda colorization tool can be found here [3]. The browser-based tool is available for use at http://hi.cs.waseda.ac.jp:8082/ [2]. The creators note that the tool is intended for non-commercial purposes only.