Natural images from the birthplace of the human eye

TL;DR

This paper introduces a publicly accessible database of calibrated natural images from the Okavango Delta, captured with detailed parameters and in formats relevant to human visual physiology, supporting research in vision science and computer vision.

Contribution

The authors provide a new, openly available database of natural images with calibration and physiological relevance, enabling diverse research applications.

Findings

Images include raw RGB and grayscale formats.

Pixel values represent cone photoreceptor photoisomerizations.

Data supports research in perception, neuroscience, and computer vision.

Abstract

Here we introduce a database of calibrated natural images publicly available through an easy-to-use web interface. Using a Nikon D70 digital SLR camera, we acquired about 5000 six-megapixel images of Okavango Delta of Botswana, a tropical savanna habitat similar to where the human eye is thought to have evolved. Some sequences of images were captured unsystematically while following a baboon troop, while others were designed to vary a single parameter such as aperture, object distance, time of day or position on the horizon. Images are available in the raw RGB format and in grayscale. Images are also available in units relevant to the physiology of human cone photoreceptors, where pixel values represent the expected number of photoisomerizations per second for cones sensitive to long (L), medium (M) and short (S) wavelengths. This database is distributed under a Creative Commons Attribution-Noncommercial Unported license to facilitate research in computer vision, psychophysics of perception, and visual neuroscience.