MENU CLOSE

IT・科学

AI Photo Colorization Brings “Memories” of Prewar Okinawa

Scene from a Naha City marketplace. Artificial Intelligence (AI) colorization of the photo is augmented by information from local records and memories. (reproduction/redistribution of photo without permission is prohibited)
Scene from a Naha City marketplace. Artificial Intelligence (AI) colorization of the photo is augmented by information from local records and memories. (reproduction/redistribution of photo without permission is prohibited)

目次

Monochrome (black and white) photos of Okinawa from 1935, ten years before the island was ravaged by the fires of war, are being colorized by Artificial Intelligence (AI). The Asahi Shimbun and Okinawa Times, in cooperation with Tokyo Metropolitan University professor Hidenori Watanabe, are working to bring the memories of Okinawans back to life. Using the latest technology and the testimony of local residents, we are being given a glimpse into Okinawan daily life 82 years ago. (Satoko Yonaha)

【PR】聞こえない人たちが導いてくれた手話の世界~フリーで活躍する手話通訳士
Scene form a Naha City marketplace. On the left is the original monochrome photograph. At center is the AI-colorized version. On the right is the final version in which the AI-rendered colorization has been augmented with additional color information from local records and testimony. (reproduction/redistribution of photo without permission is prohibited)
Scene form a Naha City marketplace. On the left is the original monochrome photograph. At center is the AI-colorized version. On the right is the final version in which the AI-rendered colorization has been augmented with additional color information from local records and testimony. (reproduction/redistribution of photo without permission is prohibited)

To Okinawa with Colorized Photos

The photo was taken in 1935 by a reporter from the Osaka branch of the Asahi Shimbun. A large collection of monochrome photographic negatives have been preserved at the Osaka headquarters of the paper. Included in this collection are photos of prewar Okinawa, which are all the more historically significant and precious because they are among the few such records to survive destruction in the fires of World War Two.

These photos are now being colorized using AI technology developed by a research group headed by Waseda University professor Hiroshi Ishikawa. Taking a leave of absence from my job at the Okinawa Times, I am at present using the photos in media research I am conducting at the laboratory of Tokyo Metropolitan University professor Hidenori Watanabe. For my current project, I have set off for Okinawa with several colorized photos to gather stories about the locations where the photos are thought to have been taken, as well as to interview local residents who may be able to provide additional information about them.

Recently discovered box containing negatives of 1935 photographs of Naha, Itoman, Koja Village, and other Okinawa locations. The negatives are preserved on curled-up segments of film strip in a box imprinted with the Fuji Film corporate logo of the period. (reproduction/redistribution of photo without permission is prohibited) (Photo courtesy of Asahi Shimbun)
Recently discovered box containing negatives of 1935 photographs of Naha, Itoman, Koja Village, and other Okinawa locations. The negatives are preserved on curled-up segments of film strip in a box imprinted with the Fuji Film corporate logo of the period. (reproduction/redistribution of photo without permission is prohibited) (Photo courtesy of Asahi Shimbun)

Colorization process uncovers Okinawa hajichi tattoos on wrists of old women in photos

I brought a photo of a marketplace scene with me on my Okinawa trip.

The photo of the “Naha Ufumachi” marketplace – which was located in present-day Higashi-machi district of Naha – depicts a lively scene of rickshaws and throngs of women and children.

In it, long-haired women in kimonos wait on customers by bamboo baaki baskets filled with various wares.

In the late 1980s, when I was just beginning elementary school, my mother used to bring me to public markets and farmers’ markets in Naha City. At the time, you could still occasionally see old women in kimonos carrying bamboo vegetable baskets on their heads. So I experienced a strong sense of nostalgia when I first saw the 1935 marketplace photograph.

Looking closely at the colorized photo, my gaze was drawn to the woman sitting just behind the one closest to the camera. I could just make out something around her wrist that was unclear in the monograph original – hajichi tattooing that was unique to Okinawa at the time. According to tradition, women were given hajichi tattoos as ceremonial symbols of marriage status and coming-of-age.

The tattoos are distinctly visible in the colorized version of the photo. In color, they are imbued with an intimate sense of life at the time that is not present in the monochrome photos of such tattoos I had seen previously.

Hajichi tattooing was prohibited by official government decree in 1899, and is a long since vanished cultural practice. But seeing the tattoos like this, I experienced a real sense of the history-evoking power of the colorization process.

Tattooing made distinctly visible through colorization. (reproduction/redistribution of photo without permission is prohibited)
Tattooing made distinctly visible through colorization. (reproduction/redistribution of photo without permission is prohibited)

Can AI Find Things that Humans Cannot?

That said, the longer I looked at it, I could not shake the sense that there was something not quite right about the AI-colorized image. The colors in the foreground did not match those in the background. While the AI had confidently assigned color values to background objects such as trees and buildings and to the skin tones of the people in the people in the photo, the wares in the bamboo baskets and other objects jumbled in the foreground were indiscriminately colored with an overall brownish tone haphazardly accented with white highlights.

AI is capable of “learning” and assigning the correct colors to objects it can recognize, such as seascapes and human hair. However, it runs into difficulty assigning color to objects it cannot recognize – for example, Okinawan agricultural products that are very different from those produced in mainland Japan. Apparently, the AI in this case did not “know” the unique objects and colors of the Okinawa region.

That said, even I, an Okinawan native, had no idea as to the identity of, and correct colors for, the wares in the marketplace baskets and other produce shown in the foreground of this 82-year-old photo.

AI cannot be expected to assign colors that a human cannot even correctly identify. But then, perhaps someone who had been alive at the time might be able to identify them.

On my journey in search of 1935 colors, a central aim of my quest would be to identify the objects in that photo.

Scene from a Naha City marketplace. Monograph original taken in 1935 by a reporter for the Osaka Asahi Shimbun (reproduction/redistribution of photo without permission is prohibited)
Scene from a Naha City marketplace. Monograph original taken in 1935 by a reporter for the Osaka Asahi Shimbun (reproduction/redistribution of photo without permission is prohibited)

Yams Were Bigger Back Then

I showed the colorized version of the photo to Masakazu (?) Itokazu (83), who was born and raised near the Naha Ufumachi marketplace. He says he has clear memories of the marketplace, where he used to play with friends as a five- and six-year-old.

Sitting before a computer screen and viewing the colorized photo with interest, Mr. Itokazu remarked “This has a real sense of depth and volume you don’t get with the black and white version.” Poring over the agricultural produce in the photo with a magnifying glass, he began to explain what we were looking at:

“The objects lumped together in the left foreground are yams. In prewar times, they were brown-colored and bigger than the yams we have these days. I’m guessing these were brought to market from Yambaru.”

“Next to those are some shima rakkyo (a variety of pickled scallion that is smaller and more pungent than the varieties familiar to mainland Japanese; “shima” or “island” is a prefix commonly attached in common Japanese usage to the names of Okinawan agricultural products). These were rather small rakkyo.”

“The woman in the whitish kimono you can see in the background is selling shima kabocha (Okinawan pumpkins).”

“But I can’t tell what the woman closest to the camera is selling.”

Standing by his side, his wife Chieko also looked at the photo intently.

“That does look like shima rakkyo,” she said. “But you can’t really tell. It might be some other kind of vegetable.”

Masakazu Itokazu pores over the colorized photo. (photo by Satoko Yonaha) (reproduction/redistribution of photo without permission is prohibited)
Masakazu Itokazu pores over the colorized photo. (photo by Satoko Yonaha) (reproduction/redistribution of photo without permission is prohibited)

Memories of a Lively Marketplace

In the end, although we were unable to definitively identify all of the items on sale in the marketplace, I was able to hear many stories about “the old days” as a result of our talk.

The marketplace used to open at 8 in the morning, and it would soon fill up with people carrying bamboo baskets on their heads laden with produce from towns to the south such as Kochinda (present day Yaesecho), Oroku, and Itoman.

“The vendors from Naha had stalls with roofs,” Mr. Itokazu remembers, “but the vendors from farther away had to make do with open-air spots, and scrambled to arrive at the market earliest so they could set up in the best ones. Then they would use their money to buy rolls of cloth and kombu seaweed at the market to take back home with them.”

The area of the marketplace shown in the photo was a section for produce vending. Other sections specialized in items such as rice, barley, sugar, and fish.

What is the old woman selling? (photo by Satoko Yonaha) (reproduction/redistribution of photo without permission is prohibited)
What is the old woman selling? (photo by Satoko Yonaha) (reproduction/redistribution of photo without permission is prohibited)

Searching for the Bamboo Basket Contents

Still, what was in those bamboo baskets?

While even the clear, vivid memories of Mr. and Mrs. Itokazu were not enough to identify the items, I was nevertheless still determined to find out what they were. After a search through collections of other prewar photos, I still could not identify those stringy looking vegetables in the marketplace picture.

My next step was to visit an exhibit of the 1935 photographs being held at the offices of the Okinawa Times, where I interviewed various people in front of the marketplace picture.

I decided to approach every person who looked like they might be old enough to have been alive when the picture was taken. However, as the closing time for the exhibit approached, I was still unable to find anyone who could help me identify the stringy vegetables. Then, twenty minutes from closing time, I saw a man looking intently at several marketplace photos.

“Hello,” I said to the man. He responded, pointing at the picture, “I wish that woman selling winter melon would turn around so we could see her face.”

“Those things that look like watermelon slices are actually winter melon,” he continued. “In the old days, they used to sell them like that. When I was a little boy, my aunt used to sell winter melon at the marketplace. Sometimes when I would play around there, she would give me a little pocket money…Still, even if the woman in the picture turns around I don’t know if it will really be my aunt or not…”

Prewar scene from the former “Naha Ufumachi Grand Market”, which was located in present-day Naha City’s Higashi-machi district (reproduction/redistribution of photo without permission is prohibited)
Prewar scene from the former “Naha Ufumachi Grand Market”, which was located in present-day Naha City’s Higashi-machi district (reproduction/redistribution of photo without permission is prohibited)

Memories Return, But…

Nodding while the elderly gentleman talks, I said “I’d like her to turn around and face the camera, too. Unfortunately, there are no photos here where she does that. But if you can tell me about what the marketplace was like back in those days, I would appreciate it.”

“Let me borrow that for a moment,” he said, looking at my reporter notebook. I handed it over, and he proceeded to provide narration for a map of the old marketplace he began sketching.

According to his story, the vegetable produce section of the market was far back from the main road, next to the section that sold fish and other seafood and seaweed products.

“Were the vegetable produce and seafood/seaweed products distinctly separated from each other?”, I asked.
“I was six years old at the time,”he said.“I have no memory at all about what was being sold there.”

“I can’t make out what’s being sold in this baaki basket in the foreground of this colorized photo,” I said.
“It’s some kind of vegetable fiber, isn’t it?”, he responded.

A gentleman at the photography exhibit who sketched a map of the old marketplace. (photo by Satoko Yonaha)(reproduction/redistribution of photo without permission is prohibited)
A gentleman at the photography exhibit who sketched a map of the old marketplace. (photo by Satoko Yonaha)(reproduction/redistribution of photo without permission is prohibited)

Oh, That’s Nachora…

An elderly woman passing by who overheard our conversation whispered “That’s nachora.” Nachora is an Okinawan dialect name for the type of seaweed most Japanese refer to as kaininso (whole algae of the Digenea simplex species, usually sold dried).

“What you see in the basket hasn’t been dried yet,” she continued. “It’s ‘raw’. Nachora is usually dried for preserving. Back in the old days, parents would feed their children nachora to de-worm them. At school, too, they would make the students take it at least once a year. It tasted so bad we would hold our noses and mix brown sugar into it to get it down. I think that’s what that is, in the picture, because they used to sell it in the marketplace on occasion.”

This single comment, heard completely by chance, ended up unlocking the mystery of the basket contents.

Later, showing the picture to my sixtysomething parents-in-law, I said “This might be nachora.”
“Yes, that’s what it is,” they said, agreeing that it was indeed a type of kaininso. “They used to make us drink it when we were children.”

Apparently, dried kaininso is still being sold at Naha marketplaces, but until now, I hadn’t even known it existed.

Doing some research, I found that the appearance of the algae in its dried form is quite different from what it looks like “raw”. Dried kaininso is a whitish-tinged brown color that makes it look like a piece of coral. But in the picture of a living specimen I find in a botany book, it looked green and stringy. This did not look familiar.

But looking at the colorized marketplace photo again, I could see that the nachora had been rendered in a pale green. Was the AI able to recognize this as kaininso after all? That is pretty impressive if it was. I began thinking that I would like to see the true shape and color of freshly harvested kaininso under early morning light, and use that information to apply the right color to the photo.

Produce in basket believed to be nachora, rendered in pale green by AI. (reproduction/redistribution of photo without permission is prohibited)
Produce in basket believed to be nachora, rendered in pale green by AI. (reproduction/redistribution of photo without permission is prohibited)

The Marketplace Burned Down in the War

The next day, using the map the elderly gentleman had sketched for me at the photo exhibition, I went out in search of the likely location of the old vegetable market. Holding the map out at various angles, I walked around Higashi-machi, finally taking pictures of what I thought might be the right spot. But I was not confident. I decided to ask an old woman walking nearby.

“The vegetable market was farther back,” she said. “Closer to the shoreline.”

At that, I set off for the shoreline.

What had been a lively marketplace in 1935 ended up being burned down in the war. Then, when Okinawa came under American military occupation after the war, the harbor abutting the old marketplace site became a major anchorage for naval shipping. All locations within a one-mile radius of the harbor were designated No-Entry zones for the local population. The heart of Naha City was emptied of its Okinawan residents, who were then unable to return to their homes.

Map of the old marketplace hand-drawn at the photo exhibition by a man the author met there. (Photo by Satoko Yonaha) (reproduction/redistribution of photo without permission is prohibited)
Map of the old marketplace hand-drawn at the photo exhibition by a man the author met there. (Photo by Satoko Yonaha) (reproduction/redistribution of photo without permission is prohibited)

Memories Roused by AI

Okinawa’s postwar recovery started just outside the perimeter of the Naha Harbor No-Entry zone. The rebuilding began in earnest in the Tsuboya (famous for its pottery) and Makishi districts of war-ravaged Naha, with the most rapid development taking place along the poorly-drained and previously sparsely populated Kokusai Street, where a popular municipal marketplace went up on the site originally frequented in the early postwar days by black marketeers.

In today’s Higashi-machi there no longer exists any trace of that marketplace of 82 years ago. The city has completely changed.

I stood on a place near the site of the old vegetable market. From this spot I could see ships. Naha Harbor was right in front of me.

We may think of AI as being omnipotent, but it turns out there are some things it cannot see. It has blind spots.

Nevertheless, thanks to my AI-colorized photo, I was able to have some worthwhile encounters during my trip. There were Mr. and Mrs. Itokazu’s stories, and the elderly gentleman I met at the photo exhibition.

I took one more good, long look at the marketplace photo. It is so evocative of the vitality of the people and of the feel of the city when it was taken. The colors of the kimonos, people’s facial expressions, even the wrinkles on their faces are all there in crisp definition. There is life in this scene. What I was looking at did not appear to be some faraway time and place. It seemed more recent and immediate.

An AI-colorized photo and memories shared with me by local residents led me to feel that the life and times of people from 82 years ago were closer to my own than I might have otherwise thought.

(Translated by M.G.Sheftall, PhD Professor of Culture and Communication Shizuoka University Faculty of Informatics)

発見された当時の写真を集めた『写真集 沖縄1935』(朝日新聞社)

関連記事

PICKUP PR

PR記事

新着記事

CLOSE

Q 取材リクエストする

取材にご協力頂ける場合はメールアドレスをご記入ください
編集部からご連絡させていただくことがございます