用python生成显示wav文件波形和增加可以在时间轴裁剪波形后保存波形文件的PYQT程序

下面是一个简单的PYQT程序，可以生成显示wav文件波形，并且可以在时间轴上裁剪波形后保存裁剪后的波形文件。

import sys
import wave
import struct
import numpy as np
from PyQt5.QtWidgets import QApplication, QMainWindow, QFileDialog
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPainter, QPen, QColor

class WaveformViewer(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle('Waveform Viewer')
        self.setGeometry(100, 100, 800, 400)
        self.filename = None
        self.data = None
        self.width = None
        self.height = None
        self.start_time = 0
        self.end_time = None
        self.mouse_pressed = False
        self.initUI()

    def initUI(self):
        self.openAction = self.createAction('Open', self.openFile, 'Ctrl+O')
        self.saveAction = self.createAction('Save', self.saveFile, 'Ctrl+S')
        self.quitAction = self.createAction('Quit', self.close, 'Ctrl+Q')

        menubar = self.menuBar()
        fileMenu = menubar.addMenu('File')
        fileMenu.addAction(self.openAction)
        fileMenu.addAction(self.saveAction)
        fileMenu.addSeparator()
        fileMenu.addAction(self.quitAction)

        self.statusBar()

    def createAction(self, text, slot, shortcut=None, icon=None, tip=None, checkable=False, signal='triggered'):
        action = QAction(text, self)
        if icon is not None:
            action.setIcon(QIcon(":/%s.png" % icon))
        if shortcut is not None:
            action.setShortcut(shortcut)
        if tip is not None:
            action.setToolTip(tip)
            action.setStatusTip(tip)
        action.setCheckable(checkable)
        getattr(action, signal).connect(slot)
        return action

    def openFile(self):
        self.filename, _ = QFileDialog.getOpenFileName(self, 'Open File', '.', 'WAV files (*.wav)')
        if self.filename:
            self.loadFile()

    def loadFile(self):
        with wave.open(self.filename, 'rb') as f:
            self.width = f.getnframes()
            self.height = f.getsampwidth() * 8
            self.data = np.zeros((self.width, 2))
            for i in range(self.width):
                frame = f.readframes(1)
                sample = struct.unpack('<hh', frame)
                self.data[i, 0] = sample[0]
                self.data[i, 1] = sample[1]

        self.end_time = self.width / f.getframerate()
        self.update()

    def saveFile(self):
        if self.filename is None:
            return

        start_frame = int(self.start_time * self.width / self.end_time)
        end_frame = int(self.end_time * self.width / self.end_time)

        data = self.data[start_frame:end_frame, :]
        with wave.open(self.filename, 'wb') as f:
            f.setnchannels(2)
            f.setsampwidth(2)
            f.setframerate(44100)
            for i in range(len(data)):
                f.writeframes(struct.pack('<hh', int(data[i, 0]), int(data[i, 1])))

    def paintEvent(self, event):
        if self.data is None:
            return

        qp = QPainter()
        qp.begin(self)
        qp.setPen(QPen(Qt.black, 1, Qt.SolidLine))

        x_scale = self.width / self.width
        y_scale = self.height / 2 / 32768

        for i in range(self.width - 1):
            x1 = i * x_scale
            y1 = -self.data[i, 0] * y_scale + self.height / 2
            x2 = (i + 1) * x_scale
            y2 = -self.data[i + 1, 0] * y_scale + self.height / 2
            qp.drawLine(x1, y1, x2, y2)

            y1 = -self.data[i, 1] * y_scale + self.height / 2
            y2 = -self.data[i + 1, 1] * y_scale + self.height / 2
            qp.drawLine(x1, y1, x2, y2)

        if self.start_time is not None and self.end_time is not None:
            qp.setPen(QPen(QColor(0, 0, 255, 127), 1, Qt.SolidLine))
            x1 = self.start_time / self.end_time * self.width
            x2 = self.end_time / self.end_time * self.width
            qp.drawRect(x1, 0, x2 - x1, self.height)

        qp.end()

    def mousePressEvent(self, event):
        if event.button() == Qt.LeftButton:
            self.start_time = event.x() / self.width * self.end_time
            self.end_time = None
            self.mouse_pressed = True

    def mouseMoveEvent(self, event):
        if self.mouse_pressed:
            self.end_time = event.x() / self.width * self.end_time
            self.update()

    def mouseReleaseEvent(self, event):
        if event.button() == Qt.LeftButton:
            self.end_time = event.x() / self.width * self.end_time
            self.mouse_pressed = False
            self.update()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    waveformViewer = WaveformViewer()
    waveformViewer.show()
    sys.exit(app.exec_())

这个程序使用 PyQt5 库创建，可以打开 wav 文件，并显示其波形，还可以在时间轴上裁剪波形并保存裁剪后的波形文件。