Perceptual experience is rich with detail.
Perhaps too rich. Visual textures and human faces are two examples of 'objects' which require a lot of information to encode in detail. These illusions might be construed as effects of biological image compression. I have developed a physiologically plausible computational model of how the density of texture is normally registered. I review these findings in order to show that texture density acts like second-order contrast, and can be modelled by divisive normalisation applied to simulated complex cells.