A Simple Explanation of SD vs. HD Video
Video is a part of an audio post houses daily routine. People are ofte surprised by how much audio engineers know about video. However, many audio post production houses are still questioning frame rate differences in HD video and time code. They’re confused about how to deal with 1080i or 720p and some don’t understand the difference between scanning in intervals or progressively, or a frame rate and/or a time code rate. We at Rocky Mountain Recorders are not confused.
Here are some simple explanations.
i or p
Here is the simplest explanation that we can give you. Televisions spray colors across your screen one line at a time, from top to bottom, faster than you can see it happening. They do this one of two different ways. They either spray the odds first, then the evens last in interlaced video. Or they will spray all the lines in sequence 1,2,3,4… progressively. These two ideas are how you get 480i or 480p. The i stands for interlaced the p stands for progressive. The benefit of progressive scanning is that you don’t get a jagged image.
480, 720, 1080
What about all those new numbers? These numbers define the quantity of lines drawn on your screen. The more lines you get on a screen the better the resolution. It’s much like photography where the more pixels you have the better the image looks, particularly when blown up to large sizes. Anything over 525 is going to be better than standard definition television and in most cases considered HD.
4:3 and 16:9
We know you don’t like ratios, but these are simple if you do this…
4:3 = old CRT (Your old heavy TV.)
16:9 = new flat screen
See no math required.
Here is a wiki with common resolutions.
Dealing with SD and HD video in audio post production is a totally different question, which I will cover in a different blog.
Thanks for reading.
