deemphasis

[ZincAlloy]

As ripping CDs with preemphasis ain't easy and LAME can set emphasis flags it would be nice if Rockbox could read the flags and apply the needed deemphasis. 

[saratoga]

Could probably be folded into libmad without too much trouble, but I don't have much motivation.  CDs with actual preemphasis are rare. 

[ZincAlloy]

Right, it's not very common anymore, but I heard some classic and audiophile labels still use it.

[NiHaoMike]

Isn't applying or removing emphasis just a matter of using the EQ to boost or attenuate high frequencies?

[saratoga]

Yes, although its probably simpler to use a basic filter in the codec itself rather then try to script changes into the rockbox EQ from inside a codec.

[bertox]

I want this feature too.

Here is the sheet of the Portal Player chip of my Sansa e250:

http://web.archive.org/web/20060707072303/http://www.portalplayer.com/products/documents/5024_Brief_Mar05.pdf

He say that can do DeEmphasis in the Dac.

Maybe Rockbox just make the command to this happen..

[saratoga]

He say that can do DeEmphasis in the Dac.

The DAC datasheet makes no mention of a filter for it, so its probably implemented in software.  Either way, its still going to be much easier to just add deemphasis to the mp3 decoder.

[bertox]

The DAC datasheet makes no mention of a filter for it, so its probably implemented in software.  Either way, its still going to be much easier to just add deemphasis to the mp3 decoder.

Are you sure? A lot of DACs do DeEmph inside..

..and maybe it is better quality than one in the Flac decoder... 

[saratoga]

You're welcome to try and find one, but its not in the datasheet and the DAC is so simple it doesn't provide any programmable filtering at all, so I doubt you're going to have much luck.  FWIW I don't think our flac decoder (or any Rockbox decoder) does emphasis.

[bertox]

Ok. 

FWIW I don't think our flac decoder (or any Rockbox decoder) does emphasis.

you misunderstand me.., i just referring to the posibility of adding DeEmph to de decoder like you say.., it's just you say'd MP3.., and i say FLAC.., cause' my albums are in FLAC and have the Flag in the CUE file.., and i want it for Flac not for MP3 too..