Mass convert MP3 to Ogg

[Mark A. Taff]

On Friday 07 July 2006 04:44, James Gray wrote:
> Pupeno wrote:
> > On Friday 07 July 2006 04:46, James Gray wrote:
> >> [2] Again, not 100% accurate.  You *can* do lossless manipulation of
> >> JPEG's and PNG's but not lossless conversion between the two as they use
> >> different compression algorithms.
> >
> > Isn't PNG's compression algorithm lossless ? I always thought it was.
>
> PNG can use either a lossless or lossy compression - it all depends on
> how the programmer decides to implement compression.  Most
> implementations of PNG encoding I've seen employ a lossy compression
> algorithm as the results are "good enough" with significant benefits for
> file size (same rationale as JPEG, and basically every other lossy
> encoding).
>
> http://www.libpng.org/pub/png/pngintro.html
>
> Have a read - it's a good high-level overview of what PNG is and isn't,
> and how it's implemented. :)
>
> Cheers,
>
> James

PNG *is* lossless, and the page you cited says the same thing.  Nowhere did it 
say that lossy compression algorithms are used.  The only place they even 
mention lossy is when taking about jpegs.

If a program were to use a lossy algorithm to create a PNG, that file would in 
fact *not* be a PNG.

Maybe you ought to reread that page yourself?

Regards,

Mark