3 ms·
Fax uses frequencies that humans can hear though (up to 4KHz)
by shawnz 7y ago
Fax uses frequencies that humans can hear though (up to 4KHz)
- Retric 7y agoSampling frequency 8 kHz/13-bit (160 samples for 20 ms frames), filtered to 200–3400 Hz. The AMR codec uses eight source codecs with bit-rates of 12.2, 10.2, 7.95, 7.40, 6.70, 5.90, 5.15 and 4.75 kbit/s. Fax machines on the other hand go up to 33kbit/s. PS: People can produce and hear frequencies well above 3400 Hz, but for phone calls people just don’t notice clipping those frequencies. If anything it helps by removing some background sounds.
- deleted 7y ago[deleted]
- shawnz 7y agoRight, so it must be the bit depth which is the problem, not the frequencies that can be reproduced