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Comment by algesten | Hacker News Reader

"See how the compressed one does not show the holes in the speaker grills in the MacBook Pro? If you don't zoom in, you would even notice the difference. "

Ehm, what?! The image on the right looks really bad and the missing holes was the first thing I noticed. No zooming needed.

And that's exactly my problem with the majority of online video (iTunes store, Netflix, HBO etc). Even when it's called "HD", there are compression artefacts and gradient banding everywhere.

I understand there must be compromises due to bandwidth, but I don't agree on how much that compromise currently is.

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Of course while reading the article you are going to be very conscious of detail and image quality because that is the subject matter of the post.

However if that MacBook Pro image was placed on the side of an article where the primary content was the text you were reading, you'd glance at the image and your brain would fill in the details for you. You probably wouldn't notice the difference in that context.

For most use cases, there likely is very little functional difference between the two images. At least, that was how I understood it.

I find the 480p setting on my plex server at home actually looks better than most of the 1080p HD streams on the internet.

Although to be fair, I suspect that a lot of times what I'm looking at are mpeg videos that have been recompressed a half dozen or more times with different encoders. Each encoder having prioritized different metrics. So, the the quality gets worse until it doesn't really matter how good the compression algorithm is. Each new re-compression is basically spending 3/4 of its bits maintaining the compression artifacts from the previous two passes.

>No zooming needed

Isn't the images above the text a zoomeed version?

>Here is a close-up of the original...

I took it to mean that we had to zoom to see that the holes were gone in the compressed version.

It indeed is, as long as we accept the first screenshot as the normal scale.

The first thing I noticed was the ringing, which is an artifact of low-pass filtering so it's a nice opportunity to go into problems with that kind of filtering. Other than that I think it was an ok teaser that gives an idea of how compression is done and what the trade-offs are.

Yep, me too - more like, if I was blind, I wouldn't notice the difference. Which is why the bitrate is always the first thing I look at when sourcing video.

But given other settings with even h.264 vs. h.265 and the source content, that isn't always a valid metric either.

I mean for fast action scenes, I rarely notice the difference between 720p and 1080p at 10ft away... but different encoding and sources, not just size alone can make significant differences.

There's another false claim like that a bit below. I can only assume that the author is close to legally blind, or uses a VGA-res display to watch the page.

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