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How to understand sample rate in case of images, it is clear to me when we are talking about the audio, but how these two are related? Is it more complex than the audio sampling?

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    \$\begingroup\$ A pixelized image has a sampling resolution in X and Y in pixels per linear unit (or perhaps better, pixels per angular unit). A movie also has a sampling interval in time... \$\endgroup\$ – Chris Stratton Jul 14 '17 at 13:40
  • \$\begingroup\$ do you mean the image itself, wich is sampled in pixels. or sampling images to get a movie? \$\endgroup\$ – Sir Sy Jul 14 '17 at 14:37
  • \$\begingroup\$ As an example think of the times you have seen the wheels appear to rotate backwards in movies on cars or wagons (westerns) - this is due to the rotation of the wheel and the effective camera sampling in terms of frames taken per second. \$\endgroup\$ – Solar Mike Jul 14 '17 at 15:07
  • \$\begingroup\$ Images and audio can relate in sample rates. @SolarMike has a pretty good analogy. They both have aliasing and sample rates. Anything with a signal like audio or video has a sample rate. Think of it has your hand trying to grab as many jelly beans in a jar. The size of your hand can determine how many jelly beans are taken out of the jar at a particular time. So the higher the sample rate, the higher quality of a signal you'll hear or see. \$\endgroup\$ – user103380 Jul 14 '17 at 19:20
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Sample rates in videos can be seen by how many intervals of... well, samples it takes in one particular time period. The chart and picture below is a good demonstration of this. It's very similar on how it works with audio as well.

enter image description here enter image description here

In calculus, you talk about the definition of integration by drawing rectangles under a curve and taking the area under that curve. However, if you make the width of the rectangles smaller, you're able to fit more rectangles under the graph and the area under the curve will be more accurate. This is true for sampling as well. The more samples you have in a given time period, the higher and cleaner quality you'll see in the video and pictures.

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  • \$\begingroup\$ I think that sample width is also important as much as number of samples. Yes you are right, higher sample rate can reconstruct signal in a more smoothier way. \$\endgroup\$ – Patrick Jul 17 '17 at 10:26

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