Bryce W Nesbitt
2005-May-05 09:29 UTC
[Asterisk-Users] Optimal prompt format (gsm, ulaw, wav) for quality effeciency space
I'll summarize on http://www.voip-info.org/ What's the best way to store static prompts in Asterisk? The system prompts are provided in gsm format. But we have no limits on disk space. Is there a better format? If we provide clips at 8 bit 8000Hz mono ulaw, and our IAX connection matches, do we gain in speed, efficiency, and quality? Will Asterisk search for the best matching clip, if we provide several formats? Do I have the sequence right, for a the media stream of a voice clip? GSM format on disk. converted on the fly to uLAW by our Asterisk box Transmitted via IAX to a (Broadvoice, LiveVOIP, VoicePulse) data center converted on the fly to ???? Transmitted via SIP to a (Level 3, RNK, XO) data center Transmitted to a point of presence converted on the fly to TDM Transmitted via the PSTN converted on the fly to analog Transmitted via last mile copper converted to sound waves by a telephone converted to brain waves by an ear Some of our prerecorded clips sound OK at the end. The clips generated by Festival Text-To-Speech sound like an Edison wax cylinder was used an an intermediate codec. Try 970-688-4348 and enter code 511#. Obviously we'd like high quality, and lack of dropped voice packets. In our particular case latency is not an issue at all, the user is simply hearing a mesage. -Bryce Nesbitt