Video - A Practical Guide to Video and Audio Compression - page 100

Quantization
errors

Word
Size

Sample Value
1

90

Sample rate

2 95

3 90

4 88

5 86

Figure 5-22 Digital waveform.

Interlacing halves this bandwidth requirement. The amount of detail is doubled at
the expense of greatly increasing the complexity of the image in the temporal domain.

5.10.4 Resolvable Detail

Placing vertical black and white lines in front of a camera and zooming out will produce
an increasing frequency gradient. Eventually the lines merge into an unfocused gray
patch. At that point you have reached the limit of resolvable detail for this system. The
resolving limits of the camera, transmission chain, or the display are all different.
Resolution is a simple calculation based on counting the number of white-to-black transi-
tions. You must take two samples at this rate to discriminate and capture a pair of verti-
cal, one-pixel wide, white and black lines. Figure 5-24 illustrates how detail increases with
frequency.
In Table 5-5, some typical values for the resolvable pixels with different kinds of
video are enumerated.