Re: [gentoo-user] NAS and replacing with larger drives

[Frank Steinmetzger]

Am Sat, Dec 10, 2022 at 09:20:17AM +0000 schrieb Wols Lists:

> > > Depending on the PVR make/model I've seen 1080p resolution recordings with
> > > .m2ts and .ts file extensions, while the codecs inside them are the same.
-------------------------------------^^^^^^^^^^^^^^^^^^^^^^^
>
> > I wasn’t aware that ts could contain h264. But then again—I never really
---------------------------------^^^^^^^
> > bothered with live TV recordings in recent years.

> I think this is confusing CONTAINER and CODEC.

Where do we confuse those two? We specifically talked of codecs and
“contain”.

> .ts is a container format, h264 is a codec. I don't understand it myself,
> either but think of ts as your directory structure and h264 as your file
> structure.

Now you are confusing me. You say you don’t understand it, but then explain
it. TS is like AVI and MKV: a file structure for the payload data. And
payload data can be all kinds of stuff, from ASS plaintext subtitles, over
opus audio to mpeg2 or h264 video.

> Incidentally, sticking this stuff in a .tar is probably okay - that's just
> another container, but sticking it in a .tar.gz is not, the gz is your codec
> and will make the file BIGGER in all probability.

Tar does not compress, it simply puts all inputs in a 1:1 stream. It does
add some metadata (filename and so on). Packers reduce data volume by
increasing information-per-byte. So if the total information stays the same
(for lossless coding), the number of bytes decreases. Encoded video data
ideally has even entropy. It is indistinguishable from random noise. That’s
why compressing it again does not yield anything, or even adds some volume
again.

-- 
Grüße | Greetings | Salut | Qapla’
Please do not share anything from, with or about me on any social network.

“Mankind must put an end to war or war will put an end to mankind.”
 – John F. Kennedy