Quality Control

བོད་ཡིག | English | 简体中文

Content
Quality Control
Original/Documented Related
File Related
Metadata Related
Image Quality Related

Quality Control

The inspection of image files is done in the same way for QC1, QC2, and QA (Quality Assurance). It involves two processes: 123

1. The first is a technical inspection of the file assuring correct imaging parameters were used when imaging, and that the file is valid. The BDRC auditing tool should be used for this purpose.
2. Image quality must then be visually inspected by a trained technician, using the following procedure:

visual review of thumbnails of all images should be done to assure completeness and consistency of the imaging. The initial review is followed by a detailed examination of a subset of the project. This visual evaluation of the images shall be conducted while viewing the images at a 1-to-1 pixel ratio, or 100% magnification on the monitor.

We recommend, at a minimum, 10 images or 10% of each batch of digital images, whichever quantity is larger, should be inspected for compliance with the digital imaging specifications and for defects in the following areas:

Original/Document Related

• Correct dimensions
  • Correct units (mm)
• Orientation
  • Modern Book- portrait/vertical
• Pecha format- landscape/horizontal
• Proportions/Distortion
  • Distortion of the aspect ratio
• Image skew
• Cropping
  • Image completeness
• Missing pages or images
  • pages missing in original are replaced by dummy pages
  • dummy pages can be added physicaly or digitally
• Number of page per image
• only 1 page per image

File Related

• Files open and display properly
• Files are not combined in a PDF or a multiple pages TIF
• Proper format
  • archival images - TIFF, Zip compression
  • web images - TIFF for text (.tif), JPEG for color images (.jpg)
• Compression
  • Zip for TIFF(archive)
  • G4 for TIF
• Color mode
  • archival images - RGB
  • web images - Bitonal/B&W for text, RGB for color images
• Bit depth
  • 24-bits for RGB
  • 1-bit for bitonal
• File size
  • web images - maximum 400 KB per image
• Image dimension
• consistent width throughout the work

Metadata Related

• Folder and images are named properly
• Data in Biblio Info Sheet is complete, including
  • Descriptive metadata (complete and accurate)
  • Technical metadata (complete and accurate)
  • Administrative metadata (complete and accurate)

Image Quality Related

• Artifacts
  • Defects
• Missing scan lines, discontinuities, or dropped-out pixels

For images taken with a camera:

• Artifacts
  • Defects
  • Dust
  • Newton’s rings
• Aimpoint variability
• Detail
  • Loss of fine detail
  • Loss of texture
  • Sharpness
  • Flare
  • Tone
    • Brightness
    • Contrast