Freesound Forums

maybe is a bit weird, but here's the problem....

there's a FLAC file (in this case can be a .WAV or any other lossless format), so how one can determine is file genuine resolution?? For example, that is not just an MP3 convertet to FLAC or WAV!!!

i know that sounds strange, but is there a way/method to do a such thing??? (preferably on PC using some software).

thanks in advance.

Yeah, some people do convert mp3s to wav, believing that this gives them back the original sound quality. It's not a matter of sampling frequency rate nor bit depth.

For mp3s only, my advice would be to:

- check the frequency range with spectral measurement; many mp3 encoders (not all) sharply cut off everything above 16kHz,

- reconvert the file to mp3 again, let say at 256kbps and see if the perceivable quality is like "over 200kbps" (good) or rather like 128kbps (bad); mp3 format does not likes to be re-encoded to mp3 again and quality lost is noticeable; other encoders - like ogg or musepack - are more resistant to that.

- trust your ears and "how the sound feels like"; every type of lossy encoder, produces it's own kind of "artifacts"; learn to recognize the artifacts, and you will know what you probably deal with. MP3 format has less depth, metallic artifacts in dynamic expressions and in background noise (which is rather soft than hard).

But remember, that some people create their music from mp3s (like 320kbps) and wavs, and then - they add some software stuff to improve quality during mixing/mastering process. Focus on good sonic content, pleasant for your ears, instead thinking whether this was mp3 or not. Mastering and/or preamps can do also a lot of harm to sound quality. Mp3 quality can be partially repaired (depending on sonic content).

I don't know if there is a software capable of measuring such things objectively, without requirement of user's interaction.

Try heavy equalizing. For example, try to isolate a very small frequency range. If a file once was lossy compressed, you should hear artefacts (like sound at that frequency suddenly cuts out at times). This is how mp3 works, it simply deletes data you can't really hear during normal use.