A Different Approach To Image Rendering

While much technical discussion of digital cameras centers around the optics and the CCD sensor, the key to superior image rendering lies in the processing of the data - analogous to the function of the human brain. Any attempt to describe a scene simply in terms of data such as brightness and color values invariably falls short of the human experience. The atmosphere and emotive powers of a photographic image can only be conveyed by an intricate assembly of all available data - one that comprises the intention behind the data.

Human Memory Color Reproduction

Canon image rendering technology aims to reproduce colors so that the result conveys the emotional intent of the photographer - colors attractive to the eye; colors that recreate the atmosphere of a scene; beautiful colors as they reside in our memory.

If the image captured by a digital camera simply presented “natural” colors as measured by the sensor, the result would not be pleasing to viewers. The first step in Canon’s image rendering, therefore, is the conversion of captured color data to standard color spaces so that images ultimately viewed on a monitor or output to a printer appear “correct” and pleasing to our mind’s eye. Canon image rendering uses proprietary algorithms based on the industry’s most extensive database of accumulated imaging data. Observed in standard color spaces, for example, reds remain bold, greens are vibrant, and blue skies are crystal clear, as we remember them to be.

Reproduction Pleasing To The Eye

Some digital camera manufacturers simply boost color densities and contrast—e.g., making whites “whiter” and blues “bluer” —to lend “brilliance” to the images. Such images may be superficially appealing, but they lack the tonal quality and definition that make a scene truly pleasing to behold.

“Beautiful to the eye” is the guiding principle behind Canon image rendering techniques. Canon’s tonal curves achieve a delicate balance so that images appear colorful and brilliant without sacrificing the subtleties that convey quality.

Reproduction of Photographic “Atmosphere”

Human perception goes beyond simple parameters, such as brightness and color. Reproducing the “atmosphere” of a scene - capturing the intentions of the photographer - therefore, cannot be achieved with simplistic AE (Auto Exposure) and AWB (Auto White Balance) algorithms.

Canon image rendering takes advantage of the huge store of AE data cultivated from the development of evaluative metering systems used in film cameras. Canon’s Intelligent AE system is thus remarkably successful at predicting the intentions of the photographer, producing the best exposures even under difficult lighting conditions.

Intelligent AWB is another important component of Canon’s image rendering system. Canon’s unsurpassed know-how in both conventional film photography and videography makes it possible to implement advanced algorithms that consistently achieve natural color balance. By maintaining this delicate balance over a wide range of lighting conditions, PowerShot cameras represent the closest approach to human perception.