Python Deep Learning - Second Edition

Speech as input data

Speech is a type of sound that typically conveys information. It is a vibration that propagates through a medium, such as air. If these vibrations are between 20 Hz and 20 kHz, they are audible to humans. These vibrations can be captured and converted into a digital signal and then used in audio signal processing on computers. They are typically captured by a microphone, after which the continuous signal is sampled at discrete samples. A typical sample rate is 44.1 kHz, which means that the amplitude of the incoming audio signal is measured 44,100 times per second. Note that this is around twice the maximum human hearing frequency. A sampled recording of someone saying "hello world" is plotted in the following diagram: ...