Video Signal Bandwidth Calculator
This calculator requires the use of Javascript enabled and capable browsers. This script determines the required viseo signal bandwidth for a given set of values. You must enter three pieces of information. Determine and enter the horizontal and vertical resolution of your intended signal, for example: 640 x 480, 800 x 600, or 1024 x 768, 848 x 600 or other legitimate entry. In these examples, the first number is the horizontal resolution, the second is the vertical resolution. Next, enter the refresh rate, or how often the display is updated, in cycles (Hz), or updates per second. If this is an interlaced signal, enter half the full frame update rate to get a correct value. The bandwidth is calculated on SONY formulae for video signals. The result values are extremely conservative. Also, the calculations do not account for filtering or other bandwidth limiting techniques.
The calculator calculates Total Pixels as the product of the horizontal and vertical resolutions, the total number of pixels per frame. Horizontal Scanning Frequency is the minimum scanning frequency required to display the input resolution at the input refresh rate. It is the minimum horizontal scanning frequency required for a fixed panel (non CRT) display to reproduce this signal. Horizontal Scanning Frequency with Retrace adds a factor to account for the additional scanning frequency required by CRT based displays to retrace between frames, a closely estimated value. Required Video Bandwidth is three times the highest frequency that will be present in the specified signal. Each component in the video reproduction chain (including cables) should have an upper frequency limit (-3dB point) higher than this value to avoid degrading the image. Exceeding the video bandwidth produces images look soft or smeared, or otherwise distorted.
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