A standard test image is a digital image file used across different institutions to test
image processing
An image is a visual representation of something. It can be two-dimensional, three-dimensional, or somehow otherwise feed into the visual system to convey information. An image can be an artifact, such as a photograph or other two-dimensiona ...
and
image compression
Image compression is a type of data compression applied to digital images, to reduce their cost for storage or transmission. Algorithms may take advantage of visual perception and the statistical properties of image data to provide superior r ...
algorithms. By using the same standard test images, different labs are able to compare results, both visually and quantitatively.
The images are in many cases chosen to represent natural or typical images that a class of processing techniques would need to deal with. Other test images are chosen because they present a range of challenges to image reconstruction algorithms, such as the reproduction of fine detail and textures, sharp transitions and edges, and uniform regions.
Historical origins
Test images as transmission system calibration material probably date back to the original Paris to Lyon fax link. Analogue Fax equipment (and photographic equipment for the printing trade) were the largest user groups of the standardized image for calibration technology until the coming of television and digital image transmission systems.
Common test image resolutions
The standard
resolution of the images is usually 512×512 or 720×576. Most of these images are available as
TIFF files from the
University of Southern California's Signal and Image Processing Institute.
Kodak has released 768×512 images, available as
PNGs, that was originally on
Photo CD
Photo CD is a system designed by Kodak for digitizing and saving photos onto a CD. Launched in 1991, the discs were designed to hold nearly 100 high quality images, scanned prints and slides using special proprietary encoding. Photo CDs are de ...
with higher resolution, that are widely used for comparing image compression techniques.
See also
*
Carole Hersee
Carole Hersee (born 25 November 1958) is an English costume designer who is best known for appearing in the centrepiece of the United Kingdom television Test Card F (and latterly Test Card J, J, Test Card W, W, and Test Card X, X), which aired on ...
*
FERET database (DARPA/NIST face recognition database)
*
Lenna
*
List of common 3D test models
References
External links
The USC-SIPI Image Database— A large collection of standard test images
— A large collection of links to various test images
—
University of Reading's set of popular test images
CIPR still images— Some sets of test images at
Rensselaer Polytechnic Institute
Rensselaer Polytechnic Institute () (RPI) is a private research university in Troy, New York, with an additional campus in Hartford, Connecticut. A third campus in Groton, Connecticut closed in 2018. RPI was established in 1824 by Stephen Van ...
(including the Kodak set)
True-color Kodak test images— The Kodak set in
PNG format
TESTIMAGES— Large collection of sample images designed for analysis and quality assessment of different kinds of displays (i.e. monitors, televisions and digital cinema projectors) and image processing techniques
{{Standard test item
Image processing
Test items