#968 Voice latency using HTC Desire

[Anonymous]

Originally created by: damien.m...@gmail.com

What steps will reproduce the problem?
1. Place test call (echo test) to a local asterisk server
2. Observe latency between your voice and returned echo
3.

What is the expected output? What do you see instead?
Immediate echo as there's no network / server delay.
Echo returns only after +500ms

What version of the product are you using? On what operating system?
HTC Desire (stock rom froyo OR gingervillain) and CSipSimple trunk / ginger.

Please provide any additional information below.
- Identical with stock ROM (froyo) and gingervillain alt ROM
- Using same local echo test with native Gingerbread SIP, latency is same (even a little higher)
- Using same echo test with PAP2T + analog phone, there's just no latency
Might this be an audio driver issue with HTC firmware ?

[Anonymous]

Originally posted by: r3gis...@gmail.com

> Using same local echo test with native Gingerbread SIP, latency is same (even a little higher)

You said it ;)
Read my comment here : issue 954.

You'll probably understand why things are like that.

And think that with +500ms you are a lucky user. HTC is the manufacturer that do things the more efficient way.
As I explain in issue 954, for now, no device has "low latency" feature. CSipSimple is ready for that, I already did an implementation that use the OpenSL-ES implementation. The missing thing : a ROM / driver / implementation of OpenSL ES that is really for low latency.

For now the device that behaves the better I found is the Acer Iconia A500. I think that's due to the fact it has Honeycomb and my hope is that Honeycomb is really optimized for voice streaming. At least echo cancellation is awesome on this device and the latency is low. And I didn't change anything to my code to get this result... just a matter of android OS implementation ;).

We (voip implementors) cry from long time about that to NDK maintainers, but that's not so easy for them to provide something. OpenSL-ES was a big step... now we are waiting for first real low latency implementations that bypass the entire android media glue. AFAIK, for now CSipSimple is the only sip app that allow to use OpenSL-ES, (even stock app still use old api), so when some manufacturer will bind opensl-es to their hardware, csipsimple will solve this problem.

So, if you want to open this issue somewhere, I think a better place would be on some of the alternative ROM. And ask them for a real low latency implementation for OpenSL-ES... Problem is that I fear they don't want to change the driver from the manufacturer (and maybe even don't know how to do, and are just packagers ;) ).
But anyway, not relevant of csipsimple project ;).

Mergedinto: 954
Status: Duplicate

[Anonymous]

Originally posted by: damien.m...@gmail.com

Thanks a lot for the quick response !

I don't know if there's any chance to see drivers/implementation improved for htc desire, as the handset nearly reached its end-of-life, and from my understanding, drivers are covered in the deep "radio" layer (manufacturer only).

Anyway, merci pour cette application ! ;)

[Anonymous]

Originally posted by: vandergu...@gmail.com

Thank you for this explanation. I know now that the only thing left to do is buy a new phone.