Digital Signal Processing Reference
In-Depth Information
2
INTRODUCTION TO VIDEO
PROCESSING
CHAPTER OUTLINE
2.1 Digital Video: Pixels and Resolution
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2.2 Digital Video: Pixels and Bits
6
2.3 Digital Video: Color Spaces 8
2.4 Video Processing Performance
9
Video processing
the manipulation of video to resize, clarify
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or compress it
is increasingly done digitally and is rapidly
becoming ubiquitous in both commercial and domestic settings.
This topic looks at video in the digital form
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so we will talk
about pixels, color spaces, etc. We start with the assumption that
video is made of pixels, that a row of pixels makes a line, and
a collection of lines makes a video frame. In some chapters we
will briefly discuss the older analog format but mainly in the
context of displaying it on a digital display.
Since this is an introductory text, and is meant to serve as
a first topic that clarifies digital video concepts, digital video is
explained primarily through pictures, with little mathematics.
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2.1 Digital Video: Pixels and Resolution
Digital video is made of pixels
think of a pixel as a small dot
on your television screen. There are many pixels in one frame of
video and many frames within one second
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commonly 60 fps.
When you look at your TV there are various resolutions such as
standard definition (SD), high definition (HD) with 720p or high-
definition with 1080p. The resolution determines how many
pixels your TV shows you.
Figure 2.1
shows the number of pixels
for these different resolutions
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as you can see the same video
frame for a 1080p TV is represented by a little over two million
pixels compared to only about 300,000 pixels for standard defi-
nition. No wonder HD looks so good.
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