Disappointing Trend in Mp3 Encoding

[ChrisCoaster]

As indicated by iTunes, an increasing proportion of mp3s are being
encoded in "joint" stereo. Does it actually "save storage" and
"improve performance" as it is touted to?

-CC

[isw]

In article
>,
ChrisCoaster > wrote:

> As indicated by iTunes, an increasing proportion of mp3s are being
> encoded in "joint" stereo. Does it actually "save storage" and
> "improve performance" as it is touted to?

IIRC, it's a "sum and difference" process (L+R, L-R), which results in a
lower bitrate for the same quality as compared to encoding the two
channels individually -- the L+R channel is just as easy/difficult to
encode as either L or R alone, while the L-R channel contains a whole
lot less information *in most cases* and so takes a smaller bitrate to
encode. If well done, there's no reason why there should be a reduction
in quality; no information is lost by that process.

Isaac

[Dave Platt]

In article ]>,
isw > wrote:

>> As indicated by iTunes, an increasing proportion of mp3s are being
>> encoded in "joint" stereo. Does it actually "save storage" and
>> "improve performance" as it is touted to?
>
>IIRC, it's a "sum and difference" process (L+R, L-R), which results in a
>lower bitrate for the same quality as compared to encoding the two
>channels individually -- the L+R channel is just as easy/difficult to
>encode as either L or R alone, while the L-R channel contains a whole
>lot less information *in most cases* and so takes a smaller bitrate to
>encode. If well done, there's no reason why there should be a reduction
>in quality; no information is lost by that process.

It's perhaps worth noting that LP records used what amounts to a
"joint stereo" encoding. The L+R signal is encoded as a horizontal
motion of the stylus, and an L-R difference signal is encoded as
vertical motion.

There were several reasons for doing this - compatibility with older
and less-expensive monaural playback turntables, improved
trackability, etc.

--
Dave Platt > AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

[Don Pearce[_3_]]

On Sun, 30 Oct 2011 22:43:08 -0700, (Dave Platt)
wrote:

>In article ]>,
>isw > wrote:
>
>>> As indicated by iTunes, an increasing proportion of mp3s are being
>>> encoded in "joint" stereo. Does it actually "save storage" and
>>> "improve performance" as it is touted to?
>>
>>IIRC, it's a "sum and difference" process (L+R, L-R), which results in a
>>lower bitrate for the same quality as compared to encoding the two
>>channels individually -- the L+R channel is just as easy/difficult to
>>encode as either L or R alone, while the L-R channel contains a whole
>>lot less information *in most cases* and so takes a smaller bitrate to
>>encode. If well done, there's no reason why there should be a reduction
>>in quality; no information is lost by that process.
>
>It's perhaps worth noting that LP records used what amounts to a
>"joint stereo" encoding. The L+R signal is encoded as a horizontal
>motion of the stylus, and an L-R difference signal is encoded as
>vertical motion.
>
>There were several reasons for doing this - compatibility with older
>and less-expensive monaural playback turntables, improved
>trackability, etc.

This form of joint stereo coding - called mid-side - is really for the
convenience of mono compatibility. It does not cause any information
loss and permits no compression.

The kind we are talking about here is intensity coding. in which the
high frequencies are combined into a single channel, with just a
little bit of side information and some panning instructions for the
codec. Low frequencies are pretty much left alone.

This does give a once-useful data reduction, but doesn't sound
particularly convincing for critical listening. It can also go
horribly wrong with some audio cues.

d

[ChrisCoaster]

On Nov 1, 4:20*am, (Don Pearce) wrote:

>
> This form of joint stereo coding - called mid-side - is really for the
> convenience of mono compatibility. It does not cause any information
> loss and permits no compression.
>
> The kind we are talking about here is intensity coding. in which the
> high frequencies are combined into a single channel, with just a
> little bit of side information and some panning instructions for the
> codec. Low frequencies are pretty much left alone.
>
> This does give a once-useful data reduction, but doesn't sound
> particularly convincing for critical listening. It can also go
> horribly wrong with some audio cues.
>
> d- Hide quoted text -
>
> - Show quoted text -
________________________

That's some of the stupidest stuff I've ever heard!! (No, not you Don
- I mean the concept!)

"Mono compatibility"? Here in the 21st century???

And summing the tops to mono vs the bottoms? Totally ASSinine if you
akse me.
Better to sum low, where directionality is less critical(except with
the ping-pong bass track on "Welcome To The Machine"). :)

Both concepts are the OPPOSITE of what we need now. How about
"surround>stereo" compatibility. Stereo is the new mono, right? And
that HF vs LF thing is a joke.

-ChrisCoaster

[Trevor]

"ChrisCoaster" > wrote in message
...
> As indicated by iTunes, an increasing proportion of mp3s are being
> encoded in "joint" stereo.

Increasing? It's always been the most popular format, and usually the best
choice other than mono!
Use Flac or Wave if you want high quality stereo.

Trevor.

[Peter Larsen[_3_]]

ChrisCoaster wrote:

> As indicated by iTunes, an increasing proportion of mp3s are being
> encoded in "joint" stereo. Does it actually "save storage" and
> "improve performance" as it is touted to?

Mid-Side encoding is OK and a wise default, intensity-stereo encoding in the
treble range is not and would be an idiotic default.

> -CC

Kind regards

Peter Larsen

[frulfinnalO]

Sorry Panavision but I too would agreee that this is a true masterpiece, but can anyone tell me if the UK R2 is the same as the Criterion edition?

[mameluk]

www.audiobanter.com is the perfect blog for anyone who wants to know about this topic. You know so much its almost hard to argue with you (not that I really would want…HaHa). You definitely put a new spin on a subject thats been written about for years. Great stuff, just great!