Description of texture loss using the dead leaves target

The computing power in modern digital imaging devices allows complex denoising algorithms. The negative influence of denoising on the reproduction of low contrast, fine details is also known as texture loss. Using the dead leaves structure is a common technique to describe the texture loss which is currently discussed as a standard method in workgroups of ISO and CPIQ. We present our experience using this method.

Based on real camera data of several devices, we can point out where weak points in the SFR_DeadLeaves method are and why results should be interpreted carefully.

The SFR_DeadLeaves approach follows the concept of a semi-reference method, so statistical characteristics of the target are compared to statistical characteristics in the image. In the case of SFR_DeadLeaves, the compared characteristic is the power spectrum. The biggest disadvantage of using the power spectrum is that phase information is ignored, as only the complex modulus is used.

We present a new approach, our experience with it and compare it to the SFR_DeadLeaves method. The new method follows the concept of a full-reference method, which is an intrinsic comparison of image data to reference data.