Relative performance measures of different digital audio encoding methods?

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mooblie
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Has anybody come across (or even: measured) the relative performances of different digital audio encoding methods? For example, a table comparing:

- noise
- distortion
- frequency response
- filesize/compression ratio
- etc....

...each being shown for different formats, at different bitrates where appropriate, such as:

- MP3
- ATRAC (mono, stereo, LP2, LP4, if anyone remembers/uses this)
- AC3
- AAC
- Ogg Vorbis
- lossless but compressed (which I suppose should always be "perfect" compared to the original, if it's working!)
- uncompresed WAV/AIFF ("the original")
- etc....

Many thanks in advance!
-----
Edit: I've located some information, but it's short on quality measurements.

Martin - DVdoctor in moderation. Everyone is entitled to my opinion.

Alan Roberts
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I know the EBU has done some work on this, but can't point to specific reports.

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Camera settings documents are held by Daniel Browning and at the EBU
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Also EBU Tech.3335 tells how to test cameras, and R.118 tells how to use the results.

John Willett
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For originating you should use 24-bit wav and nothing less.

If you are doing anything for broadcast - again, nothing less than uncompressed wav.

A compressed format may actually sound OK - but in the transmission chain it will get compressed and re-compressed and nasty digital artefacts will appear.

A compressed format is only OK for delivery to the final user where it will not be changed again.

John
 
A picture tells a thousand words, but sound tells a thousand pictures.

Dave R Smith
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Joined: May 10 2005

An interesting question.
I was only asking myself yesterday chiefly with regard to frequency response, other things being equal how does music compare on CD versus DVD.

Obviously there are different codecs and bit rates to blur any comparison.

Johns words ring true:
>A compressed format is only OK for delivery to the final user where it will not be changed again
Viewing/listening to 'Britains got talent' , via Sky, I thought the sound was 'flat'.

mooblie
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Thanks John - obviously very similar issues arise/apply in audio, as they do in video. I suppose that's not surprising really!

Martin - DVdoctor in moderation. Everyone is entitled to my opinion.