Kaushal, Your version of SoX does not have MP3 support. Since you have LAME installed, use it as a first step to produce an intermediate file that SoX supports. Then use SoX to convert the intermediate file to the desired format.
Step 1 ------ # lame --decode obd-demo.mp3 obd-demo.wav input: obd-demo.mp3 (8 kHz, 1 channel, MPEG-2.5 Layer III) output: obd-demo.wav (16 bit, Microsoft WAVE) skipping initial 1105 samples (encoder+decoder delay) Frame# 16818/16818 16 kbps # file obd-demo.wav obd-demo.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 16 bit, mono 8000 Hz Step 2 ------ # sox -V obd-demo.wav -r 8000 -b -t ul -c 1 obd-demo.ulaw sox: Detected file format type: wav sox: WAV Chunk fmt sox: WAV Chunk data sox: Reading Wave file: Microsoft PCM format, 1 channel, 8000 samp/sec sox: 16000 byte/sec, 2 block align, 16 bits/samp, 19372126 data bytes sox: 9686063 Samps/chans sox: Input file obd-demo.wav: using sample rate 8000 size shorts, encoding signed (2's complement), 1 channel sox: Output file obd-demo.ulaw: using sample rate 8000 size bytes, encoding u-law, 1 channel sox: Output file: comment "Processed by SoX" Regards, Matthew Roth InterMedia Marketing Solutions Software Engineer and Systems Developer -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users