Dead leaves model for measuring texture quality on a digital camera

摘要

We describe the procedure to evaluate the image quality of a camera in terms of texture preservation. We use a stochastic model coming from stochastic geometry, and known as the dead leaves model. It intrinsically reproduces occlusions phenomena, producing edges at any scale and any orientation with a possibly low level of contrast. An advantage of this synthetic model is that it provides a ground truth in terms of image statistics. In particular, its power spectrum is a power law, as many natural textures. Therefore, we can define a texture MTF as the ratio of the Fourier transform of the camera picture by the Fourier transform of the original target and we fully describe the procedure to compute it. We will compare the results with the traditional MTF (computed on a slanted edge as defined in the ISO 12233 standard) and will show that the texture MTF is indeed more appropriate for describing fine detail rendering.