HydrogenAudio

Lossless Audio Compression => FLAC => Topic started by: HANNARCHY on 2017-09-08 05:30:28

Title: How to rip CD audio to Hi-Res flac???
Post by: HANNARCHY on 2017-09-08 05:30:28
I'm not sure I'm getting this.  I'm trying to rip my audio CD's to 192k Hz 24bit flac, but no matter what I do, all I'm getting is 44k Hz. I can't find any option or setting to change this, yet I found the option to do 24bit as opposed to only 16.  Nevermind all that talk about wasting my drive space... I have enough to start a radio station.   I guess I COULD settle for 44k Hz, but then my plater would refuse to see it as Hi-Res.

I'm missing something, but I can't find it.   

(P.S. My phone does read Hi-Res flac files, so I have no problem there. Now if I could just rip my CD's to Hi-Res audio).

Thanks for the help.
Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Deathcrow on 2017-09-08 06:10:46
You've been misinformed. There's no high-res content on (regular) CDs that you could rip. They are 16Bit/44.1khz
Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Makaki on 2017-09-08 06:11:14
Standard Audio CD's encoding is 2-channel signed 16-bit Linear PCM sampled at 44,100 Hz.

See:
https://en.wikipedia.org/wiki/Compact_Disc_Digital_Audio

Ripping at a higher quality would just be extrapolating the data, without adding any additional quality.
Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Makaki on 2017-09-08 06:13:59
Microsoft's HDCD which is backwards compatible with regular CDs, encodes the equivalent of 20 bits worth of data in a 16-bit digital audio signal.

see:
https://en.wikipedia.org/wiki/High_Definition_Compatible_Digital
Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Porcus on 2017-09-08 10:35:54
The OP has of course gotten the essential answer: CD ripping delivers no more than what is encoded on the CD, and that is 44.1/16.

When it comes to the HDCD format:

the equivalent of 20 bits worth of data

Not quite. Notice that the Wikipedia page's alleged source for the "20" claim, Johnson/Pflaumer's 1996 AES convention paper, merely claims "approximately 19 bit precision" (p. 11). The "20" is only justified by thinking that 19.something cannot be fit in 19-bit fixed-point PCM and requires then, a 20th bit.
But the "approximately 19" includes the benefits from noise shaping, which is part of the HDCD production process, but not exclusive to the HDCD format. The format itself gives +6 dB dynamics in the loudest parts and +4 in the quietest. That requires one bit in each end, if you stick to fixed-point uncompressed PCM and an integer number of bits (which is a bit questionable; that metric would assign a higher resolution to MP3).
Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Arnold B. Krueger on 2017-09-08 13:36:10
You've been misinformed. There's no high-res content on (regular) CDs that you could rip. They are 16Bit/44.1khz

Well, that 44/16 is generally more hi-rez than:

(1) The recording venue.

(2) The playback venue

(3) The listener's ears.

(4) The original recording media if analog.

DBTs affirming otherwise will be gleefully perused. ;-)
Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Arnold B. Krueger on 2017-09-08 13:44:02
Microsoft's HDCD which is backwards compatible with regular CDs, encodes the equivalent of 20 bits worth of data in a 16-bit digital audio signal.

see:
https://en.wikipedia.org/wiki/High_Definition_Compatible_Digital

Kinda-sorta. HDCD media is plain old 16 bit data, and one or more bits was sacrificed to encode the gain changing information. This does not exactly refute the post above, but it may be helpful to shed more light on the topic.

The question then becomes how to store HDCD tracks in FLAC.

One option is to defer the HDCD decoding to playback time, and then the FLAC need only handle 16 bits.

Another option is to decode the HDCD when you rip the CD, and store the decoded 19-20 bit data into an appropriate FLAC. 

I expect that this may turn out to be the more efficient use of the storage for the music library, and provide more flexibility of the choice of music player.

The options should sound exactly the same because executed properly, the same data is sent to the digital->analog decoder.


Title: Re: How to rip CD audio to Hi-Res flac???
Post by: Porcus on 2017-09-08 15:26:44
one or more bits was sacrificed to encode the gain changing information.
Not really. The encoding is a HDCD packet every now and then - a known pseudo-random millisecond (ca.), in a number of less than a hundred times second. So for an undithered signal, you could say that the LSB is "sacrificed" a percent of the time. But if you dither down to 16 bits, you then have to argue that the HDCD "dither" from the Pacific device makes a difference compared to whatever dither a different device employs.

IIRC, it is more efficient to store HDCDs as 16-bit and decode on-the-fly (my preferred solution).

I have had some issues with track-by-track decoding, so if one wants to decode the files to store as 24-bit FLAC, one should likely HDCD-process a single image (and if desired, cut into single tracks afterwards). This provided the CD does not compile both HDCD and non-HDCD tracks, then.