My situation is that I've started to use a linux based MediaBox. The problem was/is that in my country the digital storage hardwares (external/internal HDDs) are VERY expensive (maybe because the atrist-just, but anyway...), so I've chosen the strategy to use a general PC Motherboard & CPU/RAM with DebianDog (linux distro) to play media content on TV via home FTP (by the router), what is as much compressed as it just can be. So, I would save as much space for new contents as it could be with software coding solutions.
On my only external HDD, the half of the contents are movies, and the other half are music and audio-books. And now, the HDD is almost totally full.
Music and audio-books are in mainly MP3 - as it is always -, some of them are coded with OptimFrog, but those are the ones which I would store in lossless format.
I've started to search, and what I've found yet is that the best one which can compress more - and which is playable realtime - is OGG.
But I'm not sure. I haven't read over professional audio-compress forums yet, so I can imagine there is a better one, with much slower encoding time and more CPU consumption and what is not well-known therefore.
So I would wait with starting to encoding all my audios, because I have to choose the best one - I mean "best" with "best compression ratio", with about a mid-quality.
I would choose different encoding for music and for audio-books. Maybe you know, what I mean : audio books are speech, so fot those one a different compression would needed, which is specialised for speech.
For speech (audio-books), a quality ~about~, with a 22KHz sampling rate and 8 - or 12, if available - bitdepth would be enought. About a quality with an audible quality radio stream (with built in speakers). I don't know, if that would improve compression more for *that* encoder, but in speak I really don't like heavy bass frequenties, or even not any bass at all. So bass registers could be eliminated from audio-book records too.
For music, a good pop quality would be enough. I'm listening classical music too, and other genres (like 70's Disco, 80's Disco, jazz-noir, dark-(movie-)ambient music, chamber, etc), but my ears are not so perfect. A quality about equal with a 64kbps OGG would enough, I think.
Slow encoding time is NOT a problem. At my workplace, I can use a quite strong PC to do the encodings, while I working on other things. And if an AM3 Phenom (3.2 GHz) would be OK with 2GB for decoding realtime, CPU/RAM consumption can reach that because I will use that PC ONLY for playing music and videos, NOTHING ELSE.
But in that case I would like to use the BEST compression ratio, the most agressive lossy audio compression, what is available.
Would You, professionals, recommend me a lossy audio compression with these specs?!
THANKS IN ADVANCE!