QuadMesh 对象没有属性图？

Question

使用光谱图作为基础计算光谱特征会产生错误'QuadMesh' object has no attribute 'plot'

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

import librosa as lr
from librosa.core import stft, amplitude_to_db
from librosa.display import specshow


HOP_LENGTH = 2**4
SIZE_WINDOW = 2**7

# For the test
spec = pd.read_csv('spec.csv', index_col=0)
spec = np.array(np.abs(spec))
time = np.array(normal.index)
audio = pd.read_csv('audio.csv', index_col=0).to_numpy().squeeze()
sfreq = 2205

# Calculate the spectral centroid and bandwidth for the spectrogram
bandwidths = lr.feature.spectral_bandwidth(S=spec)[0]
centroids = lr.feature.spectral_centroid(S=spec)[0]

# Convert spectrogram to decibels for visualization
spec_db = amplitude_to_db(spec)

# Display these features on top of the spectrogram
fig, ax = plt.subplots(figsize=(10, 5))
ax = specshow(spec_db, x_axis='time', y_axis='hz', hop_length=HOP_LENGTH)
ax.plot(times_spec, centroids)
ax.fill_between(times_spec, centroids - bandwidths / 2, centroids + bandwidths / 2, alpha=.5)
ax.set(ylim=[None, 6000])
plt.show()

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-47-896743695f65> in <module>()
     15 fig, ax = plt.subplots(figsize=(10, 5))
     16 ax = specshow(spec_db, x_axis='time', y_axis='hz', hop_length=HOP_LENGTH)
---> 17 ax.plot(times_spec, centroids)
     18 ax.fill_between(times_spec, centroids - bandwidths / 2, centroids + bandwidths / 2, alpha=.5)
     19 ax.set(ylim=[None, 6000])

AttributeError: 'QuadMesh' object has no attribute 'plot'

期望的输出

Answer 1

您已经在创建一个子图

fig, ax = plt.subplots(figsize=(10, 5))

所以不是

ax = specshow(spec_db, x_axis='time', y_axis='hz', hop_length=HOP_LENGTH)

您应该传入要使用的子图（Axes）。

specshow(spec_db, ax=ax, x_axis='time', y_axis='hz', hop_length=HOP_LENGTH)