Today we spoke about Digital Image Processing and why we use it.
We use it for editing pictures, it provides a flexible environment for successive experimental attempts to achieve some desired effect.
It allows us to manipulate, enhance and transform photos that are not available when using darkroom based photography.
We also spoke about digital camera imaging system and digital camera image capture. Below are the slides from the powerpoint as they describe these better than I would:
We spoke about pixelization, this can be seen by the human eye if the sensor array resolution is too low. If you increase the number of cells in the sensor array then the resloution of the image will also increase. Modern sensor devices have more than one million cells.
Below is a picture of pixelization:
To capture images in colour, red, green and blue filters are placed over the photocells.
Each cell is assigned three 8 bit numbers (giving 2^8 = 256 levels) corresponding to is red, green and blue brightness value e.g. A pixel has:
- red brightness level of 227
- green level of 166
- blue level of 97
Below are the slides for the digital camera optics and the digital image fundamentals slides (for extra info):
Pixels are individually coloured, they are only ab approximation of the actual subject colour.
The Dynamic range of a visual scene is effectively the number of colours or shades of grey(grey scale).
However, the range of digitized images are fixed by the number of bits(bit-depth) the digital system uses to represent each pixel.
This determines the maximum number of colours or shades of grey in the palette.
Below is an image of a typical digital image processing system looks like:
We spoke about what digital image processing was:
Analysis:
Manipulation:
Enhancement:
NOTE: http://lodev.org/cgtutor/filtering.html A site that lets you look at how filtering works.
Transformation:
In the lab:
In the lab we looked at tutorial videos for Adobe Premiere Pro CS4.
The like to the tutorial site is :
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