2010-07-08 06:04:35

by Viral Mehta

[permalink] [raw]
Subject: bluetooth data rate vs VDP

Hi,
I am new to bluetooth and sorry if posting at a wrong place.

I have a very basic question,
As I read through documents, Bluetooth 2 can support max data rate of 2Mbps or upto 3Mbps.

Then how can a profile like "Video Distribution Profile" work at such a low speed. If I am not wrong VDP is used for streaming of Video, how can Video streaming be achieved at such a lower data rate ?
Is there something like data rate can be increased with VDP like profile ?

Thanks,

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2010-07-08 14:05:50

by Luiz Augusto von Dentz

[permalink] [raw]
Subject: Re: bluetooth data rate vs VDP

Hi,

On Thu, Jul 8, 2010 at 2:49 PM, Viral Mehta <[email protected]> wrote:
> I want to send RAW video data. For e.g., read from /dev/fb0 and stream it...
> Is it possible at the first hand? (I guess, in theory, yes)

Yes, it is possible, but it probably will require a lot more bandwidth
than something encoded.

> I also had a question whether encoding/decoding is done by VDP profile
> or I have to write some application on top of VDP profile. ??

The profile doesn't do anything, it only defines, but yes you most
likely will be reading rtp data from bluetooth socket and then you
have do decode it yourself.

--
Luiz Augusto von Dentz
Computer Engineer

2010-07-08 11:49:40

by Viral Mehta

[permalink] [raw]
Subject: RE: bluetooth data rate vs VDP

Hi,
Thanks for the reply
>From: Luiz Augusto von Dentz [[email protected]]
>On Thu, Jul 8, 2010 at 9:04 AM, Viral Mehta <[email protected]> wrote:

>> Then how can a profile like "Video Distribution Profile" work at such a low speed. If I am not wrong VDP is used for streaming of Video, how can >Video streaming be achieved at such a lower data rate ?

>For low/webcam quality is more than enough I guess, if you think about
>it is not that different from using a phone such as N900/iphone and do
>a video call over 3G , so I don't see any problem in doing it over
>bluetooth, just use the same codec and you will going to get about the
>same thing. Also the think with vdp is that if the device supports the
>same codec as used in the video call you can pretty much sent it as it
>is, no additional encoding/decoding.

I want to send RAW video data. For e.g., read from /dev/fb0 and stream it...
Is it possible at the first hand? (I guess, in theory, yes)
I also had a question whether encoding/decoding is done by VDP profile
or I have to write some application on top of VDP profile. ??

>> Is there something like data rate can be increased with VDP like profile ?

>Yes, bluetooth 3.0.

--
Luiz Augusto von Dentz
Computer Engineer

______________________________________________________________________

This Email may contain confidential or privileged information for the intended recipient (s) If you are not the intended recipient, please do not use or disseminate the information, notify the sender and delete it from your system.

______________________________________________________________________

2010-07-08 11:29:14

by Luiz Augusto von Dentz

[permalink] [raw]
Subject: Re: bluetooth data rate vs VDP

Hi,

On Thu, Jul 8, 2010 at 9:04 AM, Viral Mehta <[email protected]> wrote:
> Hi,
> I am new to bluetooth and sorry if posting at a wrong place.
>
> I have a very basic question,
> As I read through documents, Bluetooth 2 can support max data rate of 2Mbps or upto 3Mbps.

If you mean EDR, yes it is up to 3Mbps, but with Bluetooth 3.0 you can
much higher data rate.

> Then how can a profile like "Video Distribution Profile" work at such a low speed. If I am not wrong VDP is used for streaming of Video, how can Video streaming be achieved at such a lower data rate ?

For low/webcam quality is more than enough I guess, if you think about
it is not that different from using a phone such as N900/iphone and do
a video call over 3G , so I don't see any problem in doing it over
bluetooth, just use the same codec and you will going to get about the
same thing. Also the think with vdp is that if the device supports the
same codec as used in the video call you can pretty much sent it as it
is, no additional encoding/decoding.

> Is there something like data rate can be increased with VDP like profile ?

Yes, bluetooth 3.0.

--
Luiz Augusto von Dentz
Computer Engineer