Subject:Converting wave to G.711 u-Law

Posted by: doublecrisis

Date:10/30/2004 4:26:31 PM

for working on a IVR system I need to convert around 400 voice 44.1KHz 16 Bit format wave file to 8KHz, 8 Bit, G.711 u-Law format Raw File.
Well, I'm not a experianced user of Sound Forge, but I played to do that for a week- means tried every thing I could think of- and every result made me pretty mad. now it's driving me crazy.
something sound like from the hell effect, something's sound stratched 5 times.
Now I have only 3 days to finish this job.
Could anybody give me a clue?

Subject:RE: Converting wave to G.711 u-Law

Reply by: musicvid10

Date:10/30/2004 8:02:16 PM

Use the Resample function to change the file to 8khz, then Save As your desired format.

Subject:RE: Converting wave to G.711 u-Law

Reply by: doublecrisis

Date:10/30/2004 10:47:12 PM

I did.
Resample to 8KHz and saved as raw file it made file stretched about 5 times.
it sound really bad.

Subject:RE: Converting wave to G.711 u-Law

Reply by: musicvid10

Date:11/1/2004 9:26:22 AM

To save using the G.711 u-Law codec, you should save use the InterVoice .ivc extension, not .raw

I just ran a quick test, resampling some 44.1 to 8khz, and saving to .ivc using G.711 u-Law and it worked fine.

Subject:RE: Converting wave to G.711 u-Law

Reply by: doublecrisis

Date:11/1/2004 11:26:53 AM

as you said, converting to ivc file works fine.
but what I need to archive is make it to raw file.
current equipment only support raw file.
that is my problem... -_-;;;;;

Subject:RE: Converting wave to G.711 u-Law

Reply by: Sonic

Date:11/1/2004 12:04:00 PM

I believe there may be a bug in 7.0 where the internal sample rate of the raw save template gets "stuck". Try this:

1) open a 16/44.1 .wav file and resample to 8 kHz
2) Save As...raw with the Default Template
3) allow the .raw file to re-open (choose 16/44.1 if it isn't)
4) close the .raw file
5) re-open the original .wav and resample to 8 kHz
6) Save As... raw, custom template, u-law
7) allow it to re-open, select u-law 8 kHz and verify

You should only have to do this once to get the template "stuck" on 8 kHz, then proceed as usual.

J.

Subject:RE: Converting wave to G.711 u-Law

Reply by: doublecrisis

Date:11/1/2004 1:46:55 PM

I'm talking to the tech-support and they says that's system bug, so there's no way to do that.
as far as I know 4.0 working fine.
while I'm talking to them I tried 6.0 and that ver. of SF has same issue.

Subject:RE: Converting wave to G.711 u-Law

Reply by: Sonic

Date:11/1/2004 6:49:01 PM

6.0 could not auto-resample a save, so this cannot be the same issue. Make sure you are opening with the right number of channels and sample rate and realize that u-law is a lossy compression algorithm (for 16-to-8-bit, anyway).

J.