Homepage Introduction Scanning: Master and Derivative Images Watermarking Database and Metadata Web Delivery

THE SAN (BUSHMAN) PHOTOGRAPHS OF DOROTHEA BLEEK

Technical information
Introduction

This project was modelled on the Campbell Collections digital imaging projects at the University of Natal Durban. The technical specifications are not identical however as explained below. This is the first digital imaging project at the University of Cape Town Libraries. Comments are appreciated.

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Scanning: Master and Derivative Images

The 310 black and white photographs were scanned at 600 dpi on a flatbed Epson Expression 1640XL scanner using Epson Twain Pro software at full size. The unretouched images were saved as  TIFF master files. 

Master images: TIFF files

  • Resolution: 600 dpi

  • Bit depth: 8-bit gray (Std) 

  • Image size: roughly 1800 x 3000 pixels

  • File size: approximately 4 MB

  • Uncompressed and unsmoothed

Using custom scripts in Corel Photo-Paint 9 software, two derivative files (thumbnail and larger web ready images)  were created from these master files. The brightness, contrast and intensity levels were adjusted using the Brightness-Contrast-Intensity filter by 10, 9 and 10 respectively for some of these derivate files to enhance visibility.

Thumbnail images: JPEG files

  • Resolution: 72 dpi

  • Bit depth: 8-bit gray (Std) 

  • Image size: 65 pixels on the short side

  • File size: 5.5 - 7 KB

  • Compression: 20

  • Smoothing: 20

Web ready images: JPEG files

  • Resolution: 150 dpi

  • Bit depth: 8-bit gray (Std) 

  • Image size: 250 pixels on the short side

  • File size: 55 - 65 KB

  • Compression: 20

  • Smoothing: 20

View the photographs

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Watermarking Images
The web ready images are digitally watermarked with Digimarc software to prevent unauthorised use.

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Database and Metadata
Information about each photograph, including the image number, negative number (assigned from a previous project) and caption on back the back,  was input in an MS Access database. If the same subject appears in more than one photograph, this has been noted. The database tables were then exported to a TXT file. The TXT file was then imported into an XML file using  XMLSpy and XMetal software.

The XML file makes use of the following Dublin Core metadata elements: 

  • Title
  • Creator
  • Subject
  • Format
  • Description
  • Identifier
  • Date
  • Rights
  • Format

The XML page was formatted with an XSL stylesheet. The thumbnails are hyperlinked to HTML pages of the larger web ready images.

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Web Delivery
This project uses both HTML pages (created in MS FrontPage) and XML pages created in XMLSpy and XMetal software. The introductory project information pages are HTML and the Selected Images page with the encoded metadata is XML. 

The XML page can only be viewed in Internet Explorer 5.0 and above; the XML page can not be viewed in Netscape.

View the XSL style sheet for the project.
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