Compressing Voice Sound.

Boki, since no one has suggested it, what I'd do is simply add a second independent Bluetooth sound device. There can be multiple Bluetooth devices running in the same place at once, each with its own addresses and channels, so simply treat it as you would with a physical wire, where you'd use separate wires for video and audio. Then you can use commercial Bluetooth sound stuff, like I assume you did for the video. What are you using for the video, how does it work, and how much range does it have?

--
 Thanks,
    - Win

SPP...?

Standard Parallel Port? System Platform Processor? Space Policy Project?

--
 Thanks,
    - Win

We know ! ;-)

How about an update on how your mp3 player went ?

Graham

Uhuh ! ;-)

New 'chip' ? I dunno. What kind of chip did you have in mind ? Any examples - such as ones you've been considering ? Please elaborate.

Telephone quality bandwidth - good enough ? - is a mere 4kHz. The data rate shouldn't be especially problematical ( particularly if you use a codec to reduce the data rate ).

Graham

i've seen 4..6 bits used in Phone/Voice fax type interfaces , its find for voice links.

--
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

Hi All, I am newbie. I have a image sensor, and I am sending continuosly jpg picture to client via Bluetooth. Now, I want to add voice sound.

Q1: Should I add new chip ? or just mic component only ? ( not high quality use, just record voice )

Q2: What the bandwidth do I need? ( it seems a straming protocol ... my god.. huge work... could you please advice a simple way ? )

Best regards, Boki.

If you need to synchronise the sound, you may have issues.

Bluetooth has a data channel (SCO) designed specifically for voice, and it's simply a matter of interfacing to it properly.

The channel is PCM, with (usually) the following options on voice:

A-Law u-Law

2s complement.

Of course, you have to provide the codec and perhaps the PCM clock and framing.

Cheers

PeteS

I think "it's been done" might be a Britishism? To my American ears that phrase would suggest that the work was done by someone else. That is, if you asked me "how'd your project go" and I answered "it's been done" I would be suggesting that I hired someone else to do it for me :-)

But "it's finished" or "it's done" both sound correct to my ears.

I could also say "I'm done", or "I'm finished". ("I'm" rather than "It's".) But those suggest that I am done working on the project but the project itself is perhaps not quite done - perhaps I got tired of it and quit prematurely, or perhaps it's a team effort and only my part is complete. There is also a slight echo of "I'm done for", meaning perhaps that the project concluded so poorly that I expect a failing grade.

-walter

Say, looks like from your IP address that you're in Taiwan.

How's the job market over there? All the manufacturing jobs move to mainland China?

Mike

I'd say " it's been done / finished ". It's = 'it has' in this case " it's done " is equally good. Where it's = 'it is' - lol - that's english for you !

Graham

12 bit is good for voice. Better than 8 bit. 16 bit isn't needed for voice though.

mp3 is the obvious choice of codec. There are others of course but I expect you want one that is licence free ?

Graham

what about good old fashioned ADPCM ?

martin

snip many

I think so. You will have to put a low pass filter infront of the AD, its complexity will depends on your intial sample rate (nyquist etc) but as Win said look at seperate Bluetooth, also search for bluetooth VoIP, but adpcm is free, and the source code was somewhere on the link I posted earlier.

martin

Mp3 is not good for voice, because the blocks it works with cause a minimum delay that's quite large.

Also given the constraints one can do better bit-rate wise; thing EGSM or CELP, if voice is all that's needed.

Thomas

"I don't need to do this, it's been done before." :-)

Boy, do we now get to expand our curricula vitae to include not only tutornig newbies in electronics, but tutoring ESL folks in English?

Sounds like too much work for me. ;-P

But somehow, I suddenly find myself impelled to decline "is", from memory:

I am You are He/she/it is We are You are They are I was You were He/she/it was we were you were they were I have been you have been he/she/it has been we have been you have been they have been I had been you had been

And so on, with tenses and declensions that don't even have _names_ in English! Some of those forms are _adverbs_! So, it's excusable that English is a little confusing, but I'm one of the lucky ones - a year or so of HS Latin really helps with that sort of thing, if you're of a mind to learn. :-)

Cheers! Rich

You'll need to have this fish in your ear."

"I beg your pardon?" asked Arthur.

Once he had the Babel Fish in his ear, Arthur understood perfectly. The Babel Fish lives on brainwave radiation from every source but its host. It then excretes energy in the form of exactly the correct brainwaves needed by its host to understand what was just said.

martin

It has done. ( should I say "it done" / "it is done" ? or just "Done ", also newbie in English, please advice also, thank you very much :) )

It is a building block for our player Version S.

In normal version, the audio only connect to AV output.

: )

Best regards, Boki.

"Pooh Bear" ???????: snipped-for-privacy@hotmail.com...

Of course not new chip. :)

No, no idea yet.... the one is my 12bit 1-V sigma-delta modulator ...... many problems there :p

Good, 4KHz. Telephone quality is enough, when I speed up my Bluetooth transmission and then I will select in advance.

Any suggestion codec? Just have a look/reference : )

I hope the data rate is as small as possible...

Best regards, Boki.

"Pooh Bear" ???????: snipped-for-privacy@hotmail.com...

Btw, it just one of my failed chip :p

Smart bear~ of course, I want licence free : ) and cheap cost ...

Best regards, Boki.