如何使用columnTruncateLength:232和numFramesPerSpectrogram:43将tensorflowjs的wav文件转换为频谱图?
我正在尝试在离线模式下使用tensorflowjs语音识别。使用麦克风的在线模式工作正常。但是对于离线模式,我无法找到任何可靠的库来根据所需的数组规格将wav / mp3文件转换为频谱图ffttsize:1024,columnTruncateLength:232,numFramesPerSpectrogram:43。
我尝试过的所有类似spectrogram.js的库都没有这些转换选项。 tensorlfowjs演讲明确提到光谱仪张量具有以下规格]
const mic = await tf.data.microphone({
fftSize: 1024,
columnTruncateLength: 232,
numFramesPerSpectrogram: 43,
sampleRateHz:44100,
includeSpectrogram: true,
includeWaveform: true
});
将错误作为错误获取:当下面的values
是平面数组时,tensor4d()需要提供形状
await recognizer.ensureModelLoaded();
var audiocaptcha = await response.buffer();
fs.writeFile("./afterverify.mp3", audiocaptcha, function (err) {
if (err) {}
});
var bufferNewSamples = new Float32Array(audiocaptcha);
const xtensor = tf.tensor(bufferNewSamples).reshape([-1,
...recognizer.modelInputShape().slice(1)]);
切片和校正张量后得到此错误
output.scores
[ Float32Array [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 ],
Float32Array [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 ],
Float32Array [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 ],
Float32Array [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 ],
Float32Array [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 ] ]
score for word '_background_noise_' = 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0
score for word '_unknown_' = 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0
score for word 'down' = 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0
score for word 'eight' = 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0
score for word 'five' = 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0
score for word 'four' = undefined
score for word 'go' = undefined
score for word 'left' = undefined
score for word 'nine' = undefined
score for word 'no' = undefined
score for word 'one' = undefined
score for word 'right' = undefined
score for word 'seven' = undefined
score for word 'six' = undefined
score for word 'stop' = undefined
score for word 'three' = undefined
score for word 'two' = undefined
score for word 'up' = undefined
score for word 'yes' = undefined
score for word 'zero' = undefined
回答如下:使用脱机识别的唯一要求是具有形状为[null, 43, 232, 1]
的输入张量。
1-读取wav文件并获取数据数组
var spectrogram = require('spectrogram');
var spectro = Spectrogram(document.getElementById('canvas'), {
audio: {
enable: false
}
});
var audioContext = new AudioContext();
readWavFile() {
return new Promise(resove => {
var request = new XMLHttpRequest();
request.open('GET', 'audio.mp3', true);
request.responseType = 'arraybuffer';
request.onload = function() {
audioContext.decodeAudioData(request.response, function(buffer) {
resolve(buffer)
});
};
request.send()
})
}
const buffer = await readWavFile()
无需使用第三方库就可以完成同一件事。 2个选项是可能的。
使用
<input type="file">
读取文件。在这种情况下,此answer显示如何获取typedarray。[使用http请求提供并读取wav文件
var req = new XMLHttpRequest();
req.open("GET", "file.wav", true);
req.responseType = "arraybuffer";
req.onload = function () {
var arrayBuffer = req.response;
if (arrayBuffer) {
var byteArray = new Float32Array(arrayBuffer);
}
};
req.send(null);
2-将缓冲区转换为typedarray
const data = Float32Array(buffer)
3-使用语音识别模型的形状将数组转换为张量
const x = tf.tensor(
data).reshape([-1, ...recognizer.modelInputShape().slice(1));
如果后面的命令失败,则意味着数据不具有模型所需的形状。需要将张量切成合适的形状,或者记录时应遵守fft
和其他参数。