1. Why am I not able to see any pictures when I key in a subject?

Currently, there are more textual records in PICAS than images, so when a user conducts a search, he may find that there are few or no images available on the subject keyed in. There are currently about 150,000 records in PICAS but only about 90,000 images are available for viewing. NAS decided to leave the textual records with no images in PICAS so that users will still be able to conduct a free text search for photographs available in the archives. This will save them time ploughing through manual catalogues and albums. The images in PICAS are being scanned in phases. We have completed phase I, where the majority of the 90,000 images, are from the 1990-1996 period. The pre-1990 images are still being scanned in batches.

2. I cannot seem to access PICAS. Why?

If you are accessing the Internet via a proxy server, that server may not be properly configured to recognise PICAS as a legitimate web site. Hence, you may receive messages like "The requested URL could not be retrieved". Also, the Domain Name Server (DNS) may have assumed the wrong IP address for PICAS. Please ask your network administrator for assistance.

If you are accessing the Internet from an intranet or private network, your network may be using a firewall. This is a security system in a web environment which controls and restricts information between the internet and your intranet or private network. A firewall that is set to block Java and ActiveX components may be wrongly configured to block JavaScript. Please notify your firewall administrator to rectify the situation as PICAS requires the use of JavaScript.

3. I get a "JScript error" whenever I enter PICAS. Why?

If you encounter this, you are probably using an older version of Internet Explorer or Netscape. PICAS uses new web-based technologies to bring you a user-friendly and interactive web site. You may wish to upgrade to the newest version of your web browser as older versions may not support certain functions.

4. What is the purpose of PICAS?

NAS has built a huge collection of photograph negatives, color slides, documentary films, audio and video tapes since its establishment in 1968. Thus, NAS recognizes the benefits of using IT to automate and preserve these valuable materials and also to enable easy access and promote the use of these materials by the public. Leveraging on the expertise and knowledge of KRDL in internet and intranet technology, PICAS is created.

5. PICAS was available a year ago, why did NAS only launch it now?

Although PICAS was made available on the Internet in April 1997, the majority of the images in the system were of low quality resolution. NAS decided to set the target for one year to refine the system to improve the retrieval speed and to digitise more images that are of higher resolution.

6. How does PICAS work?

The process starts from digitising the original negatives and slides. They are then stored in Kodak PhotoCD format on PhotoCDs. From the PhotoCD format, high-resolution images and thumbnails are generated and stored in CD-ROMs along with information pertaining to each image. These images are then indexed and stored into a large media repository. This is made possible with the indexing module developed in PICAS. There are two subsystems in PICAS. The first being the Retrieval System, which grants controlled access to users on the Internet so that they may search and retrieve images that are stored in the media repository. The other subsystem is the Administration System, which is a web-based Intranet solution that allows changes and updates to be made to the information corresponding to each image. The main component in the Administration System is the indexing module.

7. What are the functions of the indexing module of the PICAS system?

The indexing module is capable of describing the JPEG images into the PICAS database with the use of index fields. It also enables users to view the images to be indexed. The indexing will be done in batches of 100 and new additions are immediately available for searching. The indexing module is also used to update existing records in the PICAS database.

8. What are the subjects covered by PICAS?

PICAS covers the following broad subjects:

?People
?Organisations
?Buildings
?Forestry/Agriculture/Fisheries
?Scenes
?Industry
?Bridges
?Japanese Occupation/War in the east
?Events
?Public Utilities
?Communications

9. What are the hardware requirements to operate PICAS?

The PICAS system is operated with: Client Server : Sun Enterprise 2 Model 1200 server, running Solaris OS. User Interface : Pentium PC (133 MHz) or higher processor 16MB RAM minimum CD-ROM drive At least 100MB of free disk space Windows 95 OS Internet Explorer 4.0 browser

10. What does a user need to access PICAS?

The user requires a standard connection to the Internet. A faster connection such as that provided by Singapore ONE is recommended as pictures can be downloaded faster, enhancing the whole user experience.

11. What other features will be incorporated into PICAS to meet the increasing demand of the users?

PICAS is part of a long-term plan to provide a central Online Finding-Aids System. This Finding-Aids System will see the integration of PICAS (for image collections), MISAS (for audio-video collections) and RM Net (for file records). The objective is to provide a seamless and transparent way for the public to search and make use of the rich archives of NAS. Examples of other media that can be made available include documents, building plans, audio snippets and even 3D models of artifacts.

12. What is the underlying technology used in PICAS?

The CCIMS (Core Components for Information Management Systems) client/server modules developed by KRDL based on the Netscape Server Framework has been used to develop PICAS.

13. What are the programming languages used to develop PICAS?

The programming languages used are C/C++, Java and JavaScript.

14. What is the technological constraint faced when developing PICAS? How was this constraint overcome?

The design of the PICAS system has been constrained by the stateless nature of the WWW client/server technology. This constraint was overcome through careful understanding and exploitation of various web-based technologies.

15. Why did NAS choose to scan photographs and not other archival materials first?

Photographs are the most frequently consulted records in National Archives of Singapore. Physical retrieval and re-filing of the photoprints are laborious and time-consuming. Besides, 95% of the collection does not have a reference copy and this makes access to the collection difficult. Film ages and degrades even in a climatically controlled environment. And with each recopying, the loss of fine detail and image information is inevitable. By digitising the photograph collection, we not only provide a more user-friendly service but also address the issue of film deterioration and ensure that quality images are available.

16. Why did NAS scan from film?

There are currently 3 methods of scanning available in the market - flatbed scanning, transparency scanning and drum scanning. NAS chooses to scan from film because it can be done in a higher resolution and produces better quality images as compared to scanning from the hardcopy image.

17. Why did NAS adopt Kodak's PhotoCD format?

NAS chose to scan from film using Kodak PhotoCD technology, which was developed in 1989 and released in 1992. The technology has proven to be stable and mature and has been adopted by many libraries, museums and archives such as The Smithsonian Institute, Library of Congress, National Library of Australia, Louvre Museum, Victoria & Albert Museum and others.

Kodak's PCD format allows us to directly input from source (i.e. film). The system is able to differentiate film types (brands) and their characteristics and thus ensure accurate conversion. It allows opportunity for correction of colour and density errors, which occur in the original image that, occur due to camera exposure or during film processing.

As for compression, it uses a delicate compression scheme (Photo FCC) that does not reduce its overall quality. The compression technology is fairly open and images can be easily migrated to other common formats - JPEG, TIFF, GIF, Flashpix etc.

PCD format also meets our multiple needs of posting images on Internet to desktop printing, and high quality publishing. This is possible as each scan produces six multiple optical resolutions from Base/16 to 64Base. The turn-around time is quick at 6 seconds per 2000 dpi scan and 30 seconds per 4000 dpi scan. In all, this format produces high quality images at low storage cost - S$1 per 2000 dpi scan (for 35mm film) and S$6 per 4000 dpi scan (for 4" X 5" film).

18. Why did NAS not use digital camera to capture images instead of film?

We have evaluated the current available digital cameras but did not find them able to meet our functional requirements.

Though digital camera offers new and exciting ways of capturing images, this technology is still at its infancy. Many digital cameras available in the market are low-end models ($500-$2000) that can only capture images at resolution 480 pixels x 640 pixels at 72 dpi. In other words, images captured by these digital cameras will not register full information of the image to enable high quality prints. As such, they are only sufficient for display on monitor. The application is mainly suitable for home users.

The better ones or the so-called "high-end" models are very costly, in the region of S$25,000 or more but the quality is still not as good as what the conventional cameras of that range can produce. Typically, images captured in these higher range digital cameras can reach resolution equivalent to Photo CD 4 Base (1,024 pixels x 1,536 pixels) or even 16 Base (2,048 pixels x 3,072 pixels). Increasingly professional studios use them. But our assessment is that it will still be sometime before the technology matures and becomes widely acceptable in the archiving community.

To sum up: while the digital camera is fast in transmitting images electronically, requires no film and chemical processing, and is more environmentally friendly than traditional film, it has the following disadvantages:

1. Since the technology is still in its infancy, image quality is not good enough for large size printing. Though the high-end model can produce good printing quality, the camera is expensive.

2. Most digital cameras cannot successfully capture full colour information and details of an image as compared to film.

3. Low cost printing is not possible compared to photographic print.

4. Images stored in digital cameras are not permanent unless transferred to another medium such as CD.

5. Storage capacity is limited to the amount of memory available.

6. File transfer is extremely slow or not possible for high quality images.

19. Does NAS have any plan to digitise other materials?

Yes. There are plans to digitise some of the other more popularly consulted records within the next two years. They include maps, building plans, selected historical documents, film and sound recordings.

20. Does NAS plan to charge users for accessing pictures on Internet?

No, NAS does not have the intention to charge users for accessing the images in PICAS, as they want to encourage the use of this information as widely as possible. Users can access the images from the PICAS web site and directly print copies of the images. However, these printouts will not be of very good quality. If they want a good quality printout, they will need to come down to NAS. A fee will be charged for duplication and usage. In future, NAS has plans to implement electronic commerce to allow users to order photographs, make payment and receive their orders over the Internet.

21. How does NAS prevent its photographs being downloaded and published at other web sites?

As a security measure to prevent unauthorised duplication and downloading of our collections placed on the Internet, NAS has adopted the BatchMarc Pro watermarking software from Digimarc Corporation, USA. The system enables NAS to post images over their Internet web site to embed watermark randomly on each image. The watermark carries copyright information and links to the image creator, enabling copyright communication and authorship attribution. NAS has also purchased the Marc Spider technology that enables users and creators of digital images, to discover both authorized and unauthorized uses of their images migrating across the web. Marc Spider crawls through the Web, looking at millions of images and reports back to its owners where and when their watermarked images were found.

22. What is Photo CD?

A Photo CD is a standard type of compact disc developed by Eastman Kodak Company for the platform-independent storage and retrieval of images captured by film and digitised by a film scanner.

23. What is the scanned resolution?

Images are scanned at either an optical resolution of 2,000 or 4,000 dpi. These resolutions allow NAS to make reproduction prints larger than 30'' x 50''.

24. What is the input source for Photo CD scanning?

The input source is film. It accepts colour and black & white negatives, and slides ranging from 35mm, 120mm, to 4" x 5" format film.

25. What is the difference between Photo CD format and others?

Photo CD stores images in either 5 or 6 different resolutions. The 2,000 dpi scan has the different resolutions while the 4,000 dpi scan has 6 different resolutions.

26. What are these resolutions and their purposes?

 

	Format	Size	Image size	Purpose
i) ii) iii) iv) v) vi)	Base Base Base 4 Base 16 Base 64 Base	16128 x 192 pixel 4256 x 384 pixel 512 x 768 pixel 1024 x 1536 pixel 2048 x 3072 pixel 4096 x 6144 pixel	7k 28k 1 MB 4.5 MB 18 MB 72	Thumbnail Internet size TV or multimedia 4.5 MB HDTV A4 size output A3 size output

Yes you can. However, the quality of print depends on how good your printer is.