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: Joint Stereo - How to turn it off? (Read 27270 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Joint Stereo - How to turn it off?

I have recently installed LAME 3.97 and have been using EAC to rip music. I usually rip at -V4 or -V3 in terms of quality. Once completed and transferred to iTunes, I see that all of my songs are encoded (at least according to the iTunes info display) in joint stereo (jstereo). The LAME site indicates that normal stereo is the default for encoding above ~192 kbps, but even when I use -V3, my files still indicate "jstereo".

I want to insert a command on the command line to have LAME always encode in normal stereo when using these quality settings, but can't seem to write a command line that works correctly! When I put the command "-m s" onto the line after "-V4 - vbr new", I always get an error message and EAC will not compress the WAV file.

Could anyone provide an example of what such a command line should look like?

Thanks.

Joint Stereo - How to turn it off?

Reply #1 –
Joint stereo is on by default and you should not turn it off.

Joint Stereo - How to turn it off?

Reply #2 –
Quote from: Livy on
When I put the command "-m s" onto the line after "-V4 - vbr new", I always get an error message and EAC will not compress the WAV file.


Hi, the command is "-ms" with no spacing.

Joint Stereo - How to turn it off?

Reply #4 –
Quote from: kjoonlee on
Quote from: Livy on
The LAME site indicates that normal stereo is the default for encoding above ~192 kbps,[...]

Hi, welcome to Hydrogenaudio!

Could you tell us where it says that, please? It might need fixing.


This is directly off the LAME site at http://lame.cvs.sourceforge.net/*checkout*/lame/lame/USAGE


=======================================================================
Modes:
=======================================================================

-m m          mono
-m s          stereo
-m j          joint stereo
-m f          forced mid/side stereo
-m d          dual (independent) channels
-m i          intensity stereo
-m a          auto

MONO is the default mode for mono input files.  If "-m m" is specified
for a stereo input file, the two channels will be averaged into a mono
signal. 

STEREO

JOINT STEREO is the default mode for stereo files with fixed bitrates of
128 kbps or less.  At higher fixed bitrates, the default is stereo.
For VBR encoding, jstereo is the default for VBR_q >4, and stereo
is the default for VBR_q <=4.  You can override all of these defaults
by specifing the mode on the command line. 

jstereo means the encoder can use (on a frame by frame bases) either
regular stereo (just encode left and right channels independently)
or mid/side stereo.  In mid/side stereo, the mid (L+R) and side (L-R)
channels are encoded, and more bits are allocated to the mid channel
than the side channel.  This will effectively increase the bandwidth
if the signal does not have too much stereo separation. 

Mid/side stereo is basically a trick to increase bandwidth.  At 128 kbps,
it is clearly worth while.  At higher bitrates it is less useful.

For truly mono content, use -m m, which will automatically down
sample your input file to mono.  This will produce 30% better results
over -m j. 

Using mid/side stereo inappropriately can result in audible
compression artifacts.  To much switching between mid/side and regular
stereo can also sound bad.  To determine when to switch to mid/side
stereo, LAME uses a much more sophisticated algorithm than that
described in the ISO documentation.

FORCED MID/SIDE STEREO forces all frames to be encoded mid/side stereo.  It
should only be used if you are sure every frame of the input file
has very little stereo seperation. 

DUAL CHANNELS  Not supported.

INTENSITY STEREO

AUTO

Auto select should select (if input is stereo)
          8 kbps  Mono
    16- 96 kbps  Intensity Stereo (if available, otherwise Joint Stereo)
    112-128 kbps  Joint Stereo -mj
    160-192 kbps  -mj with variable mid/side threshold
    224-320 kbps  Independent Stereo -ms

The problem I have is that LAME appears to be encoding in joint stereo even at bitrates above ~192 kbps, which I don't want.  Thanks!

Joint Stereo - How to turn it off?

Reply #5 –
I think that only refers to CBR, and once you use a VBR preset, proper stereo settings are selected automatically.

Joint Stereo - How to turn it off?

Reply #6 –
Seems that we should update the USAGE file, as the default is always joint stereo.

(side note: perhaps we should rename the current "stereo" into "legacy stereo" and the current "joint stereo" into "stereo" ;-) )

Joint Stereo - How to turn it off?

Reply #7 –
Quote from: Mike Giacomelli on
I think that only refers to CBR, and once you use a VBR preset, proper stereo settings are selected automatically.



You may be right.  I don't understand why the files would be indicating "joint stereo" in settings like -V 3 or -V 2.  At lower bit rates, I understand the reasons for using it.  But at high bit rates (above ~192) I think it could diminish the sound quality.

Is it your opinion that, when encoding at greater than ~192 kbps, there's still a qualitative reason for using joint stereo as opposed to independent stereo?

Quote from: Gabriel on
Seems that we should update the USAGE file, as the default is always joint stereo.

(side note: perhaps we should rename the current "stereo" into "legacy stereo" and the current "joint stereo" into "stereo" ;-) )


Now I am confused...and admittedly, I am probably not an expert on the machinations of how joint stereo works.  But I would prefer to hear the music in a format as close as possible to the original, as opposed to having the channels altered in some way in order to get more bandwidth and better sound quality.  Isn't that essentially what joint stereo does?

Joint Stereo - How to turn it off?

Reply #8 –
Quote from: Livy on
Now I am confused...and admittedly, I am probably not an expert on the machinations of how joint stereo works.  But I would prefer to hear the music in a format as close as possible to the original, as opposed to having the channels altered in some way in order to get more bandwidth and better sound quality.  Isn't that essentially what joint stereo does?


Nope, a good explanation can be found on this site

http://home.freeuk.net/mostync/

Joint Stereo - How to turn it off?

Reply #9 –
Quote from: Livy on
having the channels altered in some way in order to get more bandwidth and better sound quality.  Isn't that essentially what joint stereo does?
Yes, and that's a desirable thing. But you rather want worse sound quality?

Joint Stereo - How to turn it off?

Reply #10 –
Quote from: Livy on
Now I am confused...and admittedly, I am probably not an expert on the machinations of how joint stereo works.  But I would prefer to hear the music in a format as close as possible to the original, as opposed to having the channels altered in some way in order to get more bandwidth and better sound quality.  Isn't that essentially what joint stereo does?


I found rather good explanation of what joint stereo is here.
Error 404; signature server not available.

Joint Stereo - How to turn it off?

Reply #11 –
Quote from: Gabriel on
Seems that we should update the USAGE file, as the default is always joint stereo.

(side note: perhaps we should rename the current "stereo" into "legacy stereo" and the current "joint stereo" into "stereo" ;-) )


Please do 

Joint Stereo - How to turn it off?

Reply #12 –
Quote from: Fandango on
Quote from: Livy on

having the channels altered in some way in order to get more bandwidth and better sound quality.  Isn't that essentially what joint stereo does?
Yes, and that's a desirable thing. But you rather want worse sound quality?


I guess I should have articulated what I meant - at some point, say about ~224 kbps, I would prefer not to compromise the original stereo imaging in favor of a few more bits per second.  That said, I have not read the linked explanations of joint stereo in these threads yet - maybe I'll change my mind!

Joint Stereo - How to turn it off?

Reply #13 –
Quote from: Livy on
I would prefer not to compromise the original stereo imaging in favor of a few more bits per second.
There is no compromise.  Joint stereo is just a different way of representing the same data.  It is lossless.

Quote from: Rain on
Quote from: Gabriel on
Seems that we should update the USAGE file, as the default is always joint stereo.

(side note: perhaps we should rename the current "stereo" into "legacy stereo" and the current "joint stereo" into "stereo" ;-) )
Please do 
Even if this was just a joke, +1.  Maybe it will help stem all the misconception going on that joint stereo is somehow inferior.

Joint Stereo - How to turn it off?

Reply #14 –
If it wasn't meant to be a joke, please do not change the names since this would surely lead to more confusion. There already are lots of names for how stereo signals are being coded (simple stereo, joint stereo, mid/side stereo as part of JS, intensity stereo as part of JS, channel coupling in Vorbis, etc.).

Joint Stereo - How to turn it off?

Reply #15 –
Quote from: Rain on
Quote from: Gabriel on

Seems that we should update the USAGE file, as the default is always joint stereo.

(side note: perhaps we should rename the current "stereo" into "legacy stereo" and the current "joint stereo" into "stereo" ;-) )


Please do 


Having now read through several explanations of what joint stereo is, I am inclined to agree.  I don't consider myself out of the ordinary - but the connotation of "joint" in front of a term like "stereo", which everyone knows means two-channel, is pretty obvious.  A "joint" (apart from usage while in college) is where two or more objects intersect and/or become attached. 

Thanks for everyone's assistance.  I'm glad I signed up for this site.  This has been really helpful.

Joint Stereo - How to turn it off?

Reply #16 –
Livy, those are very serious concerns you have there. I'm sure everyone will agree that with quality archiving, stereo imaging is an important matter.

Joint stereo (the mid/side kind) exists to conserve bandwidth, that's true. But there's no loss to any quality whatsoever, so it can only help compression and/or quality. The worst that can happen is that you get the same efficiency as plain left-right stereo, AFAIK.

Joint Stereo - How to turn it off?

Reply #17 –
I once read that stereo is useful when you are encoding music that contain a lot of stereo differences between both channels and encoding in joint stereo could make the quality sound even worst. The opposite would be from stereo, trying to encode tracks with little separation between both channels, while j-stereo would be a lot better because it saves bandwidth from L+R. Is this true?

Joint Stereo - How to turn it off?

Reply #18 –
Quote from: Juan C. on
I once read that stereo is useful when you are encoding music that contain a lot of stereo differences between both channels and encoding in joint stereo could make the quality sound even worst. The opposite would be from stereo, trying to encode tracks with little separation between both channels, while j-stereo would be a lot better because it saves bandwidth from L+R. Is this true?
Yes, but luckily lame joint stereo automatically choses between L+R and M+S, so you don't need to worry about it at all.

Joint Stereo - How to turn it off?

Reply #19 –
Only the second half is true.

Joint stereo has the ability to encode both ways as cabbagerat already mentioned.  Depending on the correlation between channels in any given frame, Lame will choose the most appropriate method.

Joint Stereo - How to turn it off?

Reply #20 –
Without lossy compression regular stereo (left / right) gives exactly the same result as mid / side stereo. The difference between the channel is not lost, it's saved in the side channel. However after lossy compression the results may be slightly different (worse or better) and if it's used incorrectly may cause lower quality.

Probably first versions of LAME and other codecs from the same time didn't have a good algorithm to choose whether to use regular stereo or mid/side stereo, resulting in lower quality. However now LAME uses a better algorithm, reducing the bitrate without losing quality. Actually js may increase quality with high bitrate because a difficult part may require more than 320 kbps to archive transparency with regular stereo  but less than 320 kbps with joint stereo.

Joint Stereo - How to turn it off?

Reply #21 –
Quote from: ggf31416 on
Probably first versions of LAME and other codecs from the same time didn't have a good algorithm to choose whether to use regular stereo or mid/side stereo, resulting in lower quality. However now LAME uses a better algorithm, reducing the bitrate without losing quality.


Yes, that's why I'm asking this. I've read this a long time ago and this was true because when I used j-stereo with high stereo separation, the sound was worse than encoding in simple stereo.

Good to know that LAME can change between SS and MS frames when is needed so maybe that's why j-stereo in on by default.

Joint Stereo - How to turn it off?

Reply #22 –
Quote from: ggf31416 on
Actually js may increase quality with high bitrate because a difficult part may require more than 320 kbps to archive transparency with regular stereo  but less than 320 kbps with joint stereo.

This applies to high bitrate vbr files, but also applies to any bitrate cbr files.

Joint Stereo - How to turn it off?

Reply #23 –
Quote from: Gabriel on
Seems that we should update the USAGE file, as the default is always joint stereo.

(side note: perhaps we should rename the current "stereo" into "legacy stereo" and the current "joint stereo" into "stereo" ;-) )


Quote from: Sebastian Mares on
If it wasn't meant to be a joke, please do not change the names since this would surely lead to more confusion. There already are lots of names for how stereo signals are being coded (simple stereo, joint stereo, mid/side stereo as part of JS, intensity stereo as part of JS, channel coupling in Vorbis, etc.).


How about calling JS "smart stereo"? (alliteration can be catchy...)  The fact that "joint stereo" can refer to both M/S and I/S coding methods has long been grounds for misinformation.

Joint Stereo - How to turn it off?

Reply #24 –
Old school Napster users have called, they want their evil Joint Stero myths back. 
"I never thought I'd see this much candy in one mission!"