Package: pvcobrademo
Cobra Voice Activity Detection engineMade in Vancouver, Canada byPicovoiceThis package contains demos and commandline utilities for processing real-time audio (i.e. microphone) and audio files
using Cobra voice activity detection engine.CobraCobra is a highly accurate and lightweight voice activity detection (VAD) engine.CompatibilityPython 3.7+Runs on Linux (x86_64), macOS (x86_64 and arm64), Windows (x86_64), Raspberry Pi, NVIDIA Jetson (Nano), and BeagleBone.AccessKeyCobra requires a valid PicovoiceAccessKeyat initialization.AccessKeyacts as your credentials when using Cobra SDKs.
You can get yourAccessKeyfor free. Make sure to keep yourAccessKeysecret.
Signup or Login toPicovoice Consoleto get yourAccessKey.Installationsudo pip3 install pvcobrademoUsageMicrophone DemoThe Microphone demo opens an audio stream from a microphone and detects voice activities. The following opens the default microphone:cobra_demo_mic --access_key {AccessKey}where{AccessKey}is an AccessKey which should be obtained fromPicovoice Console. It is possible that the default audio input device recognized bypvrecorderis not the one being used. There are a couple of debugging facilities baked into the demo application to solve this. First, type the following into the console:cobra_demo_mic --show_audio_devicesIt provides information about various audio input devices on the box. On a Linux box, this is the console output:'index': '0', 'name': 'HDA Intel PCH: ALC892 Analog (hw:0,0)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '2'
'index': '1', 'name': 'HDA Intel PCH: ALC892 Alt Analog (hw:0,2)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '2'
'index': '2', 'name': 'HDA NVidia: HDMI 0 (hw:1,3)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '3', 'name': 'HDA NVidia: HDMI 1 (hw:1,7)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '4', 'name': 'HDA NVidia: HDMI 2 (hw:1,8)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '5', 'name': 'HDA NVidia: HDMI 3 (hw:1,9)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '6', 'name': 'HDA NVidia: HDMI 0 (hw:2,3)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '7', 'name': 'HDA NVidia: HDMI 1 (hw:2,7)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '8', 'name': 'HDA NVidia: HDMI 2 (hw:2,8)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '9', 'name': 'HDA NVidia: HDMI 3 (hw:2,9)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '10', 'name': 'Logitech USB Headset: Audio (hw:3,0)', 'defaultSampleRate': '44100.0', 'maxInputChannels': '1'
'index': '11', 'name': 'sysdefault', 'defaultSampleRate': '48000.0', 'maxInputChannels': '128'
'index': '12', 'name': 'front', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '13', 'name': 'surround21', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '14', 'name': 'surround40', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '15', 'name': 'surround41', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '16', 'name': 'surround50', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '17', 'name': 'surround51', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '18', 'name': 'surround71', 'defaultSampleRate': '44100.0', 'maxInputChannels': '0'
'index': '19', 'name': 'pulse', 'defaultSampleRate': '44100.0', 'maxInputChannels': '32'
'index': '20', 'name': 'dmix', 'defaultSampleRate': '48000.0', 'maxInputChannels': '0'
'index': '21', 'name': 'default', 'defaultSampleRate': '44100.0', 'maxInputChannels': '32'It can be seen that the last device (index 21) is considered default. But on this machine, a headset is being used as
the input device which has an index of 10. After finding the correct index the demo application can be invoked as below:cobra_demo_mic --access_key {AccessKey} --audio_device_index 10If the problem persists we suggest storing the recorded audio into a file for inspection. This can be achieved by:cobra_demo_mic --access_key {AccessKey} --audio_device_index 10 --output_path ~/test.wavIf after listening to stored file there is no apparent problem detected please open an issue.File DemoIt allows testing Cobra on a corpus of audio files. The demo is mainly useful for quantitative performance
benchmarking. It accepts 16kHz audio files. Cobra processes a single-channel audio stream if a stereo file is
provided it only processes the first (left) channel. The following processes a file looking for voice activities:cobra_demo_file --access_key {AccessKey} --input_audio_path ${AUDIO_PATH}where{AccessKey}is an AccessKey which should be obtained fromPicovoice Console. The threshold of the engine can be tuned using thethresholdinput argument:cobra_demo_file --access_key {AccessKey} --input_audio_path ${AUDIO_PATH} \--threshold 0.9Threshold is a floating point number within[0, 1]. A higher threshold reduces the miss rate at the cost of increased false alarm rate.