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Emotional response When viewing the real world, we interpret infinite amounts of information in real time. Technical limitations with televisions, monitors and LCD screens mean that they only output a fraction of the real world they try to
emulate. They have a limited ‘colour space’ compared with that of the real world. Because video footage is played back on these devices, it is therefore impossible for video to deliver an ‘accurate’ representation of the real world. Ironically, the closer to ‘accurate’ digital video footage becomes, the
more unnatural it can look. Canon’s engineers have remedied this by taking advantage of the power of Canon's DIGIC DV processor to reproduce what they refer to as ‘emotional’ colours, tones and details - the images humans love
and remember rather than what a lens actually sees. Emotional colours
The range of possible colours in the real world is infinite, but the range of colours a camcorder can record is limited. When ‘reading’ a particular colour from the real world, the camcorder must decide which of its possible colours it will use to
represent the real colour. By forcing the camcorder to make colour approximations, colour detail is lost. Research by Canon has identified a 'colour set' to which humans have a very positive response. Canon's engineers refer to these as 'emotional' colours; redder apples, greener grass, bluer skies and warmer and more
realistic skin tones. The power of DIGIC DV has been harnessed to better and more consistently recreate these colours. Footage shot on a Canon camcorder is therefore far better at 'connecting' with and moving audiences at an emotional level. Emotional tones
Monitors and TVs do not respond to increases in brightness in an even, linear fashion. Camcorders compensate for this by using a function called gamma correction. Without this correction, images taken on a camcorder can be vastly under exposed. Processor capacity is expensive and limited, so gamma correction algorithms in camcorders are generally rudimentary. They overly ‘flatten’ response; they either over-expose highlights or compromise on shadow detail. Because of its larger processing capacity, Canon's DIGIC DV processor can handle more sophisticated gamma correction algorithms, allowing highlight detail and shadow detail to be corrected at the same time. This provides
far more natural and pleasing tonal gradations, or what Canon refers to as ‘emotional tones’. Unlike other manufacturer's image processors, Canon's DIGIC DV uses a different gamma correction curve for digital still images, resulting in far superior digital stills. This is one of the key reasons why Canon's digital
still images are superior to those created on other camcorders. Emotional detail
Before being output to medium such as video tape, camcorder images must be resized to match the resolution of the device on which they are to be displayed. For output to video tape, for example, a 2 Megapixel image is reduced to 720x480 video format.
After passing through the camcorder’s signal processing system, images therefore go through a filtering process to reduce the image size. Conventional camcorders simply strip data from the image with rudimentary algorithms known as ‘nearest neighbour’ or bilinear interpolation to reduce the image size. These processes only sample one or a few pixels from the
original pixel in order to decide on the Color of the new pixel. This results in a loss of image quality - until now seen as simply unavoidable. The abundant capacity of Canon's DIGIC DV allows Canon to use a far more advanced method for lossless resizing of images in-camera. For each output pixel, a sophisticated fractal interpolation process uses weighting from a
wide range of surrounding pixels in the input image in order to generate the final output. Much more of the input data is taken into account in order to recreate higher definition output. This improved definition is more pleasing to the human eye and is
referred to by Canon’s engineers as ‘emotional detail’. back
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