codec confusion

[Bigharry]

OK please be patient with me cos this is a basic. I get that codecs compress a video by reducing size and a bit of quality. This is actual editing I think. Then why decompress back to original "quality" before the video is viewed?. Why not just play/view the edited/reduced quality video?

[MilesAhead]

Compress a short story to zip format and try to read it. If you think about it, you have to uncompress it unless you can read stuff like &_&)THJ++J_TTTTGU+UHHGG&^%T.

[paglamon]

And that is why Codecs are better described as Coders+Decoders instead of Compressors+Decompressors. So, what you explained as Decompression is actually Decoding.

[Bigharry]

Yeah OK but what actually happens when coding? I know there is a loss of quality depending on the codec and this is in effect editing. I mean is the decoding delivering an edited lower quality product or is it re-editing back to the original "size"?

[paglamon]

I mean is the decoding delivering an edited lower quality product or is it re-editing back to the original "size"?

"Delivering an edited lower quality product".

[Exotic]

How did you compress the video? are you using any apps?