Re: proliferation of voicesystems
At 15:38 8/27/95, Thomas Grant Edwards wrote:
On Sun, 27 Aug 1995, Tatu Ylonen wrote:
Maybe someone could start writing an internet draft about "encrypted voice transmission on the internet". It should address several issues: - compression methods, sampling rate differencies, encoding methods
BTW - does anyone actually know what the voice compression is in PGPfone?
GSM lite and I think CELP. PGPFone has some serious problems with the variable latencies of real life connections. These problems will not go away until PGPFone makes the shift to APIs that are designed to deal with such problems, such as QuickTime conferencing. I hope PRZ will realize this. -- Lucky Green <mailto:shamrock@netcom.com> PGP encrypted mail preferred.
Lucky Green writes:
BTW - does anyone actually know what the voice compression is in PGPfone?
GSM lite and I think CELP. PGPFone has some serious problems with the variable latencies of real life connections. These problems will not go away until PGPFone makes the shift to APIs that are designed to deal with such problems, such as QuickTime conferencing. I hope PRZ will realize this.
And Windows95/NT has a Audio Compression Manager which comes with GSM and TrueSpeech compression drivers. The problem is, what will be done for the Unix users? A standard audio API is sorely missing in the unix world (NetWork Audio System and AudioFile aren't solutions) -Ray
Ray Cromwell writes:
The problem is, what will be done for the Unix users? A standard audio API is sorely missing in the unix world (NetWork Audio System and AudioFile aren't solutions)
It depends on what you mean by an API. If you are just talking about driver interfacing there are de facto standards at this point -- basically everyone has been adopting the sun /dev/audio ioctls. .pm
Ray Cromwell writes:
The problem is, what will be done for the Unix users? A standard audio API is sorely missing in the unix world (NetWork Audio System and AudioFile aren't solutions)
It depends on what you mean by an API. If you are just talking about driver interfacing there are de facto standards at this point -- basically everyone has been adopting the sun /dev/audio ioctls.
That's too low-level to deal with the proliferation of PC sound systems, especially since even non-intel workstations are adopting PCi buses. If I recall, /dev/audio relies on u-law/a-law encoding. That's only one component of a higher level audio system. That's like having a /dev/svga but no Motif library. Furthermore, a /dev/audio like interface doesn't admit good hardware acceleration, such as if you had to play an MPEG layerIII audio, but your sound card had a DSP. -Ray
participants (3)
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Perry E. Metzger -
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