Approaches to Editing
Technical Lecture Series
Lecture 1 - Video Basics
What is Light?
Lighting plays an essential role in video production. Both natural and artificial lighting can create atmosphere and mood, a sense of balance and dimension. Can help draw attention to specific parts of a subject, define colors, create forms and generally to produce an acceptable picture in a video movie.
Scanning / Raster
A raster image is composed of pixels broken into a grid of dots. The color values of each dot are stored in the image files with varying formats. The level of detail of an individual image is dependent on the pixel size, or spatial resolution, of the raster.
Image rasters can be read as lines which are formed into fields and frames. Light can be expressed as a sum of Red, Green and Blue values. Y=R+G+B. RGB signal can be expressed as a series of Luminance and Colour Difference signals:
-Y, (B-Y), (R-Y); or YCbCr
The Video Legacy - Pal Composite Video
Legacy Image Formats
PAL delivers a frame rate of 50i or 25p.
HD Image Formats
Additive Colour Mixing
R+G+B=White
R+G=Yellow
G+B=Cyan
R+B=Magneta
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