[Speex-dev] Transmitting synthetic speech using Speex?
reed at mobilerobots.com
Fri May 26 08:13:27 PDT 2006
Tom Grandgent wrote:
> Have you tried using 16kHz wideband? The sound quality is far superior to
> narrowband, IMO, even if you have to turn the VBR quality down (to say, 2)
> to save bandwidth.
Thanks for the info Tom!
Probably narrowband is hurting me, but my system is currently built on that. I
want to try to get acceptable performance from narrowband if possible before
trying to add wideband support to the system.
Consistant, noise-free synthesized speech certainly has fewer potentially
problematic aspects to it though, I agree... Maybe we should all just make
people type their communications in to a keyboard :)
> Reed Hedges <reed at mobilerobots.com> wrote:
>> Hello, I'm wondering if anyone has done this before and has any advice, or if
>> anyone in general has ideas about it.
>> I just implemented transmitting synthesized speech (text-to-speech) over Speex
>> (narrowband) in an application. I'm using Swift from Cepstral
>> (http://www.cepstral.com). The voice I'm using is a pretty deep male voice. I'm
>> telling Swift to generate audio at 8khz, then encoding each chunk of audio
>> output by Swift and sending it to a client.
>> One interesting thing I've noticed is that as I increase Speex's encoding
>> quality, the output in the client sounds smoother (at my normal quality value of
>> 5 or 6 it sounds OK but occasionally has a hesitation or glitch) but "thinner"
>> -- less full or less resolution. Using the noise filter and changing the
>> complexity parameter don't seem to matter.
>> I'll be experimenting with this more, but if anyone is interested I can send
>> some audio data generated by the Swift synthesizer. Or, if anyone has any
>> suggestions for how to tweak the synthesized audio for better encoding by Speex,
>> that would also be helpful (I don't know very much about audio or audio signal
>> processing yet.)
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