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Comment by xmprt | Hacker News Reader

Anecdotally, whatever YouTube has done in recently years has completely ruined a lot of 480p and 360p videos. I uploaded a native 360p video about 10 years ago and in the end card, I added small red text that was visible. And when I uploaded it at the time, it was visible on YouTube as well. Now that section just looks like a bunch of red blurry lines.

If you ever wondered why old videos look so bad, it's not just because you're used to 1080p and so 360p looks terrible in comparison. YouTube is actively reducing old video quality through whatever reencoding they're doing.

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If your original content wasn't one of YouTube's current formats it was likely reencoded. If the original was MPEG-4 part 2 or Sorensen Spark that a decade ago YouTube might just passed through, today it would be reencoded before delivery.

Their pipeline taking 1080p or 4K content to a 360p stream will produce decent quality. The encoding configuration for today's use also might be very different from the original. If their 360p profile used today ups the GOP length and drops the video bitrate the video content can definitely end up bit starved. Readable text in a 360p video would be difficult to keep readable reencoding without manual tweaking of the encoder settings.

I also wonder if old content with low viewership is just encoded on the fly with a hardware encoder and thrown into a big YouTube-wide LRU cache. Hardware encoders can have some really coarse grained settings and make low resolution/low bitrate content look pretty horrible.

I have noticed that as well. I recently stumbled across a movie clip in 240p and the thing that was most notable was that during a monologue, the actor's lips did not move at all. He turned his head a little, but his expression seemed to be frozen. After a very noticeable key frame it returned to normal shortly, but his face ended up getting stuck again. I don't recall ever seeing something like this on YouTube, not even in ultra-LQ clips from 2007.

They probably lowered the max bitrate for 360p videos.

Which might make sense for variable bitrate content, but makes no sense for videos that were only ever 360p in the first place! Youtube basically made a lot of old videos unwatchable.

Which would destroy any 360p video so they should have known better than that. Transcoding is pretty bad stuff.

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