Skip to main content ↑ ↓

Notice

Please note that most of the software linked on this forum is likely to be safe to use. If you are unsure, feel free to ask in the relevant topics, or send a private message to an administrator or moderator. To help curb the problems of false positives, or in the event that you do find actual malware, you can contribute through the article linked here.
Topic: "qval" on LAME, best setting? (Read 4749 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

"qval" on LAME, best setting?

Hi, I was ripping some cd's and noticed something while trying settings:

Currently I'm ripping my cd's on EAC to mp3 @ 320kbps CBR (That's the setting I need to use, and that's another story, so, no "lossless" suggestions please  ) so:

I tried first on the same song/CD LAME 3.90 with the --alt-preset insane switch and I got this reading while the encoder is working:

"Enconding as 44.1kHz 320 kbps j-stereo MPEG-1 layer III (4.4x) qval=2"

Then I tried LAME 3.97b1 with the -b 320 switch and got this reading:

"Enconding as 44.1kHz 320 kbps j-stereo MPEG-1 layer III (4.4x) qval=3"

Then I tried the same LAME 3.97b1 with the -b 320 -h switch and got this reading:

"Enconding as 44.1kHz 320 kbps j-stereo MPEG-1 layer III (4.4x) qval=2"

As you may notice the reading is the same on the 3.90/--alt-preset insane and when using the -h switch on 3.97b1, I'm not a tech expert but I assume that the "qval=" is the quality value, I asked before if I needed to use the -h switch in 3.97 to achieve better quality but someone sayed that it was not neccesary 'cause it was already implemented on the recommended -b 320 switch, now some questions:

Is the "qval=" actually a quality value with "1" being the best and "3" the worst and if so is there a switch to achieve that "qval=1" and thus preffering that one over "qval=2" or "qval=3"?

Currently I don't have in here high quality speakers/headphones to make a real listening test, I did some A/B/X on foobar but didn't noticed differences 'cause I was using some cheap headphones but I'd like to make my mp3's the best quality possible, again, I NEED to convert to mp3/CBR because of a dj software application I use that recommends those settings to avoid artifacts because of the time-stretch/pitch-shifting it uses, so quality is THE main thing I want to achieve

And as i said, I'm not a tech expert so excuse me if I'm asking something stupid or nonesense, but I'm curious 

Thanks!
"If the world didn't suck we'd all fall off"
- Sir Isuck Newton -

"qval" on LAME, best setting?

Reply #1 –
qval ranges from 0 to 9, 0 being theoretically the best and 9 being the worst.

In Lame 3.90, qval=0 and 1 were "broken", and 2 gave great quality and reasonable encoding speed. so qval=2 was the set in the presets.

Now in 3.97, qval=0 and 1 aren't "broken" anymore, but they're ridiculously slow and there's no real proof that they're any better than qval=2. qval=3 has been tested to be the same quality as qval=2 but a little faster to encode, so that's the new default.

"qval" on LAME, best setting?

Reply #2 –
The answer of NeoRenegade is almost correct, except from the difference of q2 and q3 in 3.97b.

What happened is that a new method was added.
From the LAME Changelog:

Quote
LAME 3.94 beta December 15 2003
          o best huffman divide in the inner loop. This should improve the quality, but PAINFULLY slow. So it is not enabled by default. Use -q0 to use it.
          o Changed -q option mapping. "-q2" until version 3.93 is now "-q3".


and later:
Quote
LAME 3.97 alpha (CVS)
          o Reworked -q1 and -q0


So, basically, you're safe for achieving the same quality. You can use -q0 , q1 or -q2 at your own desire, if you see them fit your needs.