[MP3 ENCODER] Re: VBR not as variable as Xing
I should have added that I am using the switches -b 32 -B 320 Ross. -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Re: VBR not as variable as Xing
On Sun, 5 Dec 1999, Ross Levis wrote: > I should have added that I am using the switches -b 32 -B 320 Are you also using the -v and -Vn options, where n is some number [0..9]? What n are you using? Are you running Linux, if so what does the VBR histogram look like? -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Re: VBR not as variable as Xing
Unfortunately I'm running Windows rather than Linux. I will take that plunge once it is more configuration user-friendly. The -V4 switch in v3.57 (without -v which doesn't appear to be required). I noticed that prior Lame versions required -V5 to average close to 128kb/s whereas -V4 is now closer. I notice also that silence appears to be encoding at 64kb/s rather than 32 as specified, whereas Xing VBR (normal) encodes it at 48kb/s. The major factor which concerned me was a frequency analysis I performed on a song encoded with -V5 (v3.57) which averaged around 112kb/s. It did not show anything over 16khz. I realise that without the -k option that bitrates below 128 are cut at 16khz but surely with VBR there should be higher bit-rates and so higher freqencies. Ross. -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Re: VBR not as variable as Xing
On Sun, 5 Dec 1999, Ross Levis wrote: > Unfortunately I'm running Windows rather than Linux. I will take that plunge once >it is more configuration user-friendly. The -V4 switch in v3.57 (without -v which >doesn't appear to be required). I noticed that prior Lame versions required -V5 to >average close to 128kb/s whereas -V4 is now closer. Yes, this is software in development. VBR is still a quickly changing topic. > I notice also that silence appears to be encoding at 64kb/s rather than 32 as >specified, whereas Xing VBR (normal) encodes it at 48kb/s. If the encoders are encoding this 'silence' at anything other then 32kb/s then either it isn't silence, or both encoders are broken. :) My expirence with Xing's VBR is that it often picks too low a bitrate. I would expect that it uses a watered down psycoacoustic model to select bitrate, insted of the slow lame approach. > The major factor which concerned me was a frequency analysis I performed on a song >encoded with -V5 (v3.57) which averaged around 112kb/s. It did not show anything >over 16khz. I realise that without the -k option that bitrates below 128 are cut at >16khz but surely with VBR there should be higher bit-rates and so higher freqencies. If the cutoff is turned off and on within the file it produces an audible effect. Therefor, the cutoff is selectd based on the -Vn setting and stays throught the entire file. I think that -V5 and larger have the cutoff. You can always disable the cutoff completely with -k. -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Re: VBR not as variable as Xing
how does xing vbr compare to lame, in quality? - Original Message - From: "Greg Maxwell" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Saturday, December 04, 1999 11:59 PM Subject: Re: [MP3 ENCODER] Re: VBR not as variable as Xing > On Sun, 5 Dec 1999, Ross Levis wrote: > > > Unfortunately I'm running Windows rather than Linux. I will take that plunge once it is more configuration user-friendly. The -V4 switch in v3.57 (without -v which doesn't appear to be required). I noticed that prior Lame versions required -V5 to average close to 128kb/s whereas -V4 is now closer. > > Yes, this is software in development. VBR is still a quickly changing > topic. > > > I notice also that silence appears to be encoding at 64kb/s rather than 32 as specified, whereas Xing VBR (normal) encodes it at 48kb/s. > > If the encoders are encoding this 'silence' at anything other then 32kb/s > then either it isn't silence, or both encoders are broken. :) > > My expirence with Xing's VBR is that it often picks too low a bitrate. I > would expect that it uses a watered down psycoacoustic model to select > bitrate, insted of the slow lame approach. > > > The major factor which concerned me was a frequency analysis I performed on a song encoded with -V5 (v3.57) which averaged around 112kb/s. It did not show anything over 16khz. I realise that without the -k option that bitrates below 128 are cut at 16khz but surely with VBR there should be higher bit-rates and so higher freqencies. > > If the cutoff is turned off and on within the file it produces an audible > effect. Therefor, the cutoff is selectd based on the -Vn setting and stays > throught the entire file. I think that -V5 and larger have the cutoff. > You can always disable the cutoff completely with -k. > > > > -- > MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ ) > -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Re: VBR not as variable as Xing
Ampex wrote: > how does xing vbr compare to lame, in quality? I don't have the equipment to do high quality listening tests but other tests have shown Lame to be better than the Xing encoder. I found Xing better than Fhg for joint-stereo distortion. Greg Maxwell wrote: > If the cutoff is turned off and on within the file it produces an audible > effect. Therefor, the cutoff is selectd based on the -Vn setting and stays > throught the entire file. I think that -V5 and larger have the cutoff. > You can always disable the cutoff completely with -k. Thanks for that info Greg. It was confusing me and I didn't see that documented anywhere. I will open a new thread now on this cut-off issue. Cheers, Ross. -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
