matlab [B,F.T] = SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)我想知道这个B到底是代表什么直接输SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)是输出语谱图,下面是help 的结果 ,无奈英语看不懂SPECGRAM Spectrogram using a Short-Time Fourier T

matlab [B,F.T] = SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)我想知道这个B到底是代表什么直接输SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)是输出语谱图,下面是help 的结果 ,无奈英语看不懂SPECGRAM Spectrogram using a Short-Time Fourier T
matlab
[B,F.T] = SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)
我想知道这个B到底是代表什么
直接输SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)是输出语谱图,
下面是help 的结果 ,无奈英语看不懂
SPECGRAM Spectrogram using a Short-Time Fourier Transform (STFT).
B = SPECGRAM(A) calculates the spectrogram for the signal in vector A.
SPECGRAM divides the signal into overlapping segments,windows each
segment and forms the columns of B with their discrete Fourier
transforms.
B = SPECGRAM(A,NFFT,Fs) specifies the number of FFT points used to
calculate the discrete Fourier transforms.If NFFT = [] or is not
specified the default NFFT = minimum of 256 and the length of A.Fs is
the sampling frequency which does not effect the spectrogram but is
used for scaling plots.If Fs=[] or is not specified it defaults to 2
Hz.
B = SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP) uses WINDOW to window each
overlapping segment and forms the columns of B with their zero-padded,
length NFFT discrete Fourier transforms.If you specify a scalar for
WINDOW,SPECGRAM uses a Hanning window of length NFFT.WINDOW must
have a length smaller than or equal to NFFT and greater than NOVERLAP.
NOVERLAP is the number of samples each segement of A overlaps.The
default value of NOVERLAP = length(WINDOW)/2.
还有这个B和 用fft函数出来的有什么区别啊

matlab [B,F.T] = SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)我想知道这个B到底是代表什么直接输SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)是输出语谱图,下面是help 的结果 ,无奈英语看不懂SPECGRAM Spectrogram using a Short-Time Fourier T
B = SPECGRAM(A)
计算了光谱的信号向量A,SPECGRAM将信号分为重叠部分,窗口部分并且在B列生成离散傅里叶变换.
B = SPECGRAM(A,NFFT,Fs)
指定FFT点的数量来计算离散傅里叶变换.如果NFFT =[]或没有指定默认NFFT=最低的256和向量A的长度：Fs是采样频率不影响谱图但用于缩放绘图.如果Fs=[]或没有指定则默认值为2赫兹.
B = SPECGRAM(A,NFFT,Fs,WINDOW,NOVERLAP)
使用窗口显示窗口重叠部分、补零后的B列、长度NFFT离散傅里叶变换.如果您为窗口指定一个度量,SPECGRAM采用圆形低频滤波器的长度NFFT .窗口必须有一个长度小于或等于NFFT且大于NOVERLAP .NOVERLAP是样品A重叠部分的数量,默认值NOVERLAP=length(WINDOW)/2.