Nearing the filling of my 14.5TB hard drive and wanting to wait a bit longer before shelling out for a 60TB raid array, I've been trying to replace as many x264 releases in my collection with x265 releases of equivalent quality. While popular movies are usually available in x265, less popular ones and TV shows usually have fewer x265 options available, with low quality MeGusta encodes often being the only x265 option.

While x265 playback is more demanding than x264 playback, its compatibility is much closer to x264 than the new x266 codec. Is there a reason many release groups still opt for x264 over x265?

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[–] Shimitar@feddit.it 30 points 1 year ago (3 children)

Some notes: Don't use GPU to reencode you will lose quality.

Don't worry for long encoding times, specially if the objective is long term storage.

Power consumption might be significant. I run mine what the sun shine and my photovoltaic picks up the tab.

And go AV1, open source and seems pretty committed to by the big players. Much more than h265.

[–] MonkderZweite@feddit.ch 11 points 1 year ago* (last edited 1 year ago)

Yep, gpu de- and encoding is high-speed but often lower quality and with old codec versions. Common mistake to think that gpu = better.

[–] Zedstrian@lemmy.dbzer0.com 4 points 1 year ago (3 children)

In order to encode to a specific format without unintentionally losing quality, doesn't the initial file have to be a remux?

[–] kamiheku@sopuli.xyz 7 points 1 year ago

Yes, that's right. But the point stands, you indeed shouldn't do such encoding on the GPU, it's a tradeoff of (fast) speed vs (poor) quality and (big) size. Good for when you need realtime encoding.

[–] zeluko@kbin.social 2 points 1 year ago

You can downsample from BluRay, which would give you least loss.
But if you only have some good h264 version and want space savings, you can also reencode that, while probably loosing some small amount of quality, depending on your settings.

[–] Shimitar@feddit.it 1 points 1 year ago

Indeed, but YMMV and to me quality is still good if source was not a remix but a top quality encoding

[–] pastermil@sh.itjust.works 0 points 1 year ago (1 children)

Why is the GPU reencoding bad for the quality? Any source for this?

[–] cuppaconcrete@aussie.zone 0 points 1 year ago (1 children)

Yeah that caught my eye too, seems odd. Most compression/encoding schemes benefit from a large dictionary but I don't think it would be constrained by the sometimes lesser total RAM on a GPU than the main system - in most cases that would make the dictionary larger than the video file. I'm curious.

[–] db2@lemmy.world 1 points 1 year ago

The way it was explained to me once is that the asic in the gpu makes assumptions that are baked in to the chip. It made sense because they can't reasonably "hardcode" for every possible variation of input the chip will get.

The great thing though is if you're transcoding you can use the gpu to do the decoding part which will work fine and free up more cpu for the encoding half.