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Abstract
Archaeological visualizations are very important to understand for archaeological sites. But now, archaeologists usually use the methods for old measurement systems; therefore, they cannot easily visualize the archaeological sites. The map of archaeological sites on the papers, usually used by archaeologists, is not able to understand for other people (except archaeologists).

Chinese archaeological fortress sites are huge and flat, so we cannot to see whole images on the ground. And also we cannot get air images in China. We developed new methods for the visualizations of these archaeological fortress sites.

First one is the radio-controlled model helicopter to take air pictures (images); second one is to make the digital 3D CG and Animation from the digital Photogrammetry

Introduction
The beginning of the rice cultivation in the world is said 12000 years ago in Yangtze River side in the China. Rice cultivation developed the cities (fortress sites) that surrounded clay wall and water ditches for the water-controlled systems.

From 1997, International research center for Japanese studies in Japan (Kyoto) has studied about the 5th Civilization of the world; named "Yangtze Civilization" was found around the Yangtze River area. They found some archaeological fortress sites (B.C.7000-3000) from Hu-nan and Hu-bei providences.

These fortress sites are so huge, biggest one is 3km by 4km, and difficult to make a maps of the whole plan. Then, we developed new methods for the measurement of these fortress sites.

Airborne System and Digital Mosaic

1. Radio-controlled Model Helicopter

We can use many platforms to take air pictures/images (Fig.-1) in Japan. But in China, we (foreigners) cannot use airplane and helicopter to take air pictures. Then we used radio-controlled model helicopter and metric/non-metric digital still camera.

Fig.-1 Origin of the Rice Cultivation (Left)


Fig-2 Platforms for Photogrammetry (Right)

We selected metric camera, HasselBlad MKW/E, and non-metric digital still camera, Cannon D30 with 15mm Lenses.

Radio-controlled model helicopter can rise up 300m with these cameras; we can get single picture size is following……….


HasselBlad MKW/E (with f=38mm lens)	H=300m	442mx442m
Cannon D30 (with f=15mm lens)	H=300m	452mx312m



2. Digital Mosaic

After taking air images by Cannon D30, we must make digital mosaic at the field (with use of car battery) for the fortress sites, therefore, there are so huge (Fig.-2). Digital mosaic is very useful to check the images, and useful to measure the target points.

And also, digital mosaic will quickly give us the new unknown data that we cannot see from the air. Fig-3 shows us the double ditches and radial ditches between ditches around the fortress. These ditches are considerable for the water-controlled systems. We can check and measure the important points at the fields, for example, barrage or dam and missing streams.

Cannon D30's format size is the 22.6mm by 15.6mm C-MOS format, is too small for the photogrammtric format for the large area. Then we usually use 6 by 6 images scanned from HasselBlad camera for the photogrammtric data.

Stereo Matching and Rendering

1. Stereo Matching

From the air images and the measuring data, we make DEM by the each stereo model. We used in this time, Galileo Syscom's Stereo Metric, Orthomap, and ADA system. This system is easy use for the archaeologists, and we think very important that archaeologists use these plotting machines by themselves.

It is very important that the break lines are to be checked by archaeologists themselves.


Fig.-3 Digital Mosaic (Left)

Fig.-4 Water-Controlled System (Right)




Fig-5 Water-Controlled System in ···

2. Rendering

After the plotting of data, we covered the ortho images (Fig-5) on the DEM data, and made CG (Fig.-6).

Fig.-5 Ortho Image (a part of south-west of ···


Fig.-6 3D CG (same place of Fig.-5)
Conclusion
The combination with Radio-controlled model helicopter and digital method is the good visualization method to understand the huge archaeological sites. 3D CG and Animation will become to understandable method for Cultural Heritage.