CD Pre-emphasis: How to detect? What software to rip? Tagging?

[Miska]

At least HQPlayer detects it and applies the needed correction too. If Pro is used to rip the CD, then the output is with the correction automatically.

 

[Miska]

3 hours ago, audiofool said:

Cool!  How does HQPlayer determine it needs pre-emphasis?

 

It is from the CDDA data.

 

3 hours ago, audiofool said:

Is there a way to set a tag in a FLAC file to force it?

 

No, once the data ends up in FLAC it should be already corrected without need for such measures.

 

3 hours ago, audiofool said:

Does HQPlayer do anything with HDCD?

 

No.... Only standard CDDA (RedBook), not any non-standard additions like HDCD or MQA.

 

But you won't find CDs that would have HDCD and pre-emphasis.

 

[Miska]

2 hours ago, audiofool said:

So even CD's I've ripped years ago should be handled correctly by HQPlayer for pre-emphasis since it is embedded in the CDDA data and not depending on the TOC?  Is this a newer feature of HQPlayer?

 

No, you need to use the actual physical media. Already made rips are lost case.

 

2 hours ago, audiofool said:

I have a number of CD's that are HDCD.  I am using music forums to find them since I don't believe there is any way to know for sure from the CDDA data stream?

 

I have three CD's with HDCD. A HDCD decoder will detect from the data stream. I used dbPowerAmp to rip and decode those three to 24-bit FLAC. Note that the check box in the decoder is misleading. It needs to be unset, or otherwise the decoded result will be just clipping harder.

 

I think Microsoft owns HDCD these days. But there are so few discs with it that it is not worth trying to talk to Microsoft and potentially increase license price with decoding support.

 

[Miska]

Just now, audiofool said:

For the lost cases, what about a tag in the flac file that HQPlayer could recognize? ie. preemp=yes

 

Technically possible, but just not implemented right now.

 

1 minute ago, audiofool said:

I have at least 16 discs and am using ffmpeg to decode, interesting that an HDCD decoder can detect from the data stream.

 

CD players with HDCD support do it the same way. The watch the least significant bit (LSB) for the encoded pattern. Normally this bit would be used for dither, but on HDCD it is used for control data.

 

2 minutes ago, audiofool said:

I'm curious how ffmpeg is avoiding the license fee.

 

Cutting some corners in this explanation... ffmpeg has a lot of such stuff. It is free and open source, nobody is doing it commercially, so it doesn't make any money someone could sue for "damages".