>
> I made a short test with lame-3.32.
>
> With the new Takehiro routines the encoder speed has improved.
> However, I noticed some high frequency artefacts that were not present
> in the last three or four releases. I tested both with -b 160 -m s and
> with 128kbps settings. The ringing artefacts are minute but noticeable. I
> also used xmms with a highpass engaged and with stereo enhancement effect
> plugin activated to ease my listening tests.
>
> I�m not sure where this comes from.
> Do Takehiro's and Leonid's latest enhancements comply?
>
> Could somebody check the implementation of late Mr. Huffman's invention?
>
I think they are compatible: Before switching to Takehiro's routines,
I checked them pretty carefully: I encoded castanets.wav with
Takehiro's routines, but with the ISO bitcount formula. The bits
saved by Takehiro's routines were then wasted. This procedure
produced an mp3 file different than the original mp3, since different
Huffman tables where used for the lossless compression, but the
decoded wav files were identical.
So I am pretty sure the only difference in output between 3.32 and 3.31
is that there are *more* bits available per frame.
Could you try using a larger normalization constant in the ATH formula?
The ATH stuff is relatively new and will have its biggest effect
on high frequencies.
On line 216 quantize.c:
ath -= 114; /* MDCT scaling. From tests by macik and MUS420 code */
Something like ath -= 200 will completely disable it.
Mark
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