Shoutbox

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Originally posted by M-Head
I know, but is the quality loss really that noticable?

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Well, with a Lame-encoded MP3 at 192 KBPS it isn't that noticeable, however it's never bad to crave for the better. And again, it's not just the quality that bothers me, it's also the stupidness and wastage behind the idea of having to recompress. It bothers me fundamentally.

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Originally posted by anubis_kree_
When I rip CD's to 192kbps MP3's so I can listen to them on my comp I don't notice any difference. So the quality reduction really shouldn't be anywhere near noticeable...man sock you're a perfection freak!

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That's different. Audio CD data has a very large size, so compressing it is something you'd want to do. In my case, the audio is already highly compressed. Also, audio CD data is in a very high quality, so you can compress it very efficiently. When recompressing data (with lossy codecs), some quality is always lost.



Now to answer Cookish...

Well, you're not making much sense..... Let's get a few things straight:

Wave (.wav) files use PCM (Pulse-Code Modulation) to store digital audio data (audio CDs use it too). PCM is a standard digital audio representation system. This system uses no compression, so 128 KBPS at PCM sounds like total crap.

If I really wanted to preserve the quality at any cost, I'd have to save the audio at the standard PCM bitrate (1440 KBPS or something), and either leave it that way (as a .wav file) or use a lossless audio codec (such as FLAC) to recompress the data without losing any quality. Using a lossless codec would still generate a pretty big file size, since lossless codecs don't discard any data. So in both cases, I get a big file size (in my case, ~28mb on PCM and ~17mb on FLAC), which isn't very nice. In comparison, at the original 128 KBPS WMA compression, the audio size is only ~2.6mb.

Now let's review your post!

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Anyways... saving to a normal wav doesn't compress the audio again. (Unless you use some special filters and stuff or decreases the bitrate and such of course).

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True, but it generates a huge file. A lossless audio codec can help there, but it's still pretty big, as I mentioned above.

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Saving the uncompressed audio stream is also useless. You wouldn't have anything to play it with.

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When I said "uncompressed audio stream", I was referring to PCM data. So this is the same thing as above really.

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It needs to be recoded (but not nessecairly recompressed) into a new codec.

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The whole point of media codecs is to compress/decompress the data. There's no media codec that doesn't (de)compress. If I want it uncompressed, I can put the raw decompressed audio data in a PCM (.wav) file, which is again the same thing as above.

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So, if you keep the bitrates, samplerates, etc... and you save to wav, nothing is lost... as far I can tell...

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I can't keep the same bitrate when moving from MP3 to PCM without losing quality, as PCM has no compression. The audio in MP3 is decompressed before it can be played by the computer, so in fact every song can be represented at 1440 (?) KBPS, as PCM, at the same quality as the source.