# Unit 1 Lesson 8 20-21

**URL:** <https://forum.code.org/t/unit-1-lesson-8-20-21/33366>\
**Category:** Unit and Lesson Discussion\
**Created:** [September 20, 2020, 9:06pm UTC](https://forum.code.org/t/unit-1-lesson-8-20-21/33366 "2020-09-20T21:06:09Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![coxc](https://avatars.discourse-cdn.com/v4/letter/c/5daacb/32.png) [@coxc](https://forum.code.org/u/coxc)\
**Post date:** [September 20, 2020, 9:06pm UTC](https://forum.code.org/t/unit-1-lesson-8-20-21/33366/1 "2020-09-20T21:06:09Z")

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The figure in the slide deck for this lesson that is labeled _Layers of Abstraction in Color Images_ is confusing me. My understanding of sampling comes from other kinds of data, so perhaps the term is used differently here. In the Layers of Abstraction figure, it looks like the pixels are sampled in order to produce the digital image. But my understanding is that the light reflected off an object is sampled to produce a digital image. The sampling happens when the data is first recorded, or perhaps when it is converted from one format or resolution to another. I don’t see how it fits between pixels and display. Can someone explain this to me, or point me to a good resource?

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**Author:** ![gjschmidt](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.code.org/gjschmidt/32/4922_2.png) [@gjschmidt](https://forum.code.org/u/gjschmidt)\
**Post date:** [September 21, 2020, 10:49pm UTC](https://forum.code.org/t/unit-1-lesson-8-20-21/33366/2 "2020-09-21T22:49:28Z")

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Sampling here means how “often” the color is captured. Here is how I explained it:  
You point a digital camera at a beautiful landscape. The camera doesn’t capture it all. It captures 10MP of data. Something in the camera picks which 10MP to record. That’s the sampling. Now that I have the sample I need to figure out the color for each of the pixels. That’s the pixel layer. Finally I convert that to binary and store it on my SD card.

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**Author:** ![laura\_zoumberis](https://avatars.discourse-cdn.com/v4/letter/l/9f8e36/32.png) [@laura\_zoumberis](https://forum.code.org/u/laura_zoumberis)\
**Post date:** [September 16, 2021, 5:32pm UTC](https://forum.code.org/t/unit-1-lesson-8-20-21/33366/3 "2021-09-16T17:32:39Z")

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Thank you! This is helpful.