我正在尝试使用 ffmpeg-python 将视频文件压缩到 python 中的目标大小作为我课程的一部分，我一直收到这个错误，说它不知道编码器。不知道我打算做什么，因为这对我来说确实是一个全新的空间。我是否打算安装编解码器或其他东西，或者我可以使用其他替代方案？
import os, ffmpeg
##import section:this part is where I import all of the modules I will use
import tkinter
import shutil
from tkinter import filedialog
import os
def fileSelect(): #start of fileSelect function
global startingLocation #declares startingLocation as global variable
global originalName #declares originalName as global variable
global fileType #declares fileType as global variable
startingLocation = filedialog.askopenfilename(initialdir="/", title="Select file", #tkinter function that opens file explorer, lets user select file saves the file path as a variable
filetypes=(("video files", "*.mp4"),("images", "*.jpg*")))
originalName = os.path.basename(startingLocation) #os function that gets the actaul file name from the path string
print (originalName) #print statement to check if originalName has been found
fileType = startingLocation.split('.') #splits original name where any full stop in found and saves array as variable
fileType = fileType[-1] #changes variable to have the str value of the final item in the array; the file type
fileType = '.' + fileType #adds fullstop to the start of the file type so i dont have to repeatedly do it
print (fileType) #print statement to check file type is found correctly
def outputSelect(): #start of outputSelect function
global outputLocation #declares outputLocation as global variable
outputLocation = filedialog.askdirectory(initialdir="/", title="Select folder") #tkinter function that opens file explorer, lets the user select of folder as saves the folder path as a variable
def fileNewName(): #start of fileNewName function
global customName #declares customName as global variable
customName = input("Enter the end name of your file") #simple code assigning user input to the custom name vairable
customName = customName + fileType #add the fileType onto the end of the custom name
def compress(): #start of compress function
fileSelect() #calls the fileSelect function
outputSelect() #calls the outputSelect function
fileNewName()
global src
global dst #calls the fileNewName function
src = startingLocation #assigns startingLocation str as src, so the shutil module is able to use it in a cleaner way
dst = outputLocation #assigns outputLocation dst as src, so the shutil module is able to use it in a cleaner way
shutil.copy(src, dst) #shutil command that copies the file from src to dst
src = outputLocation + '/' + originalName #reassigns src as the location of the file copy
dst = outputLocation + '/' + customName #reassigns dst as the location of the file copy but with a new name
shutil.move(src,dst)
def compress_video(video_full_path, output_file_name, target_size):
# Reference: https://en.wikipedia.org/wiki/Bit_rate#Encoding_bit_rate
min_audio_bitrate = 32000
max_audio_bitrate = 256000
probe = ffmpeg.probe(video_full_path)
# Video duration, in s.
duration = float(probe['format']['duration'])
# Audio bitrate, in bps.
audio_bitrate = float(next((s for s in probe['streams'] if s['codec_type'] == 'audio'), None)['bit_rate'])
# Target total bitrate, in bps.
target_total_bitrate = (target_size * 1024 * 8) / (1.073741824 * duration)
# Target audio bitrate, in bps
if 10 * audio_bitrate > target_total_bitrate:
audio_bitrate = target_total_bitrate / 10
if audio_bitrate < min_audio_bitrate < target_total_bitrate:
audio_bitrate = min_audio_bitrate
elif audio_bitrate > max_audio_bitrate:
audio_bitrate = max_audio_bitrate
# Target video bitrate, in bps.
video_bitrate = target_total_bitrate - audio_bitrate
i = ffmpeg.input(video_full_path)
ffmpeg.output(i, os.devnull,
**{'c:v': 'libx264', 'b:v': video_bitrate, 'pass': 1, 'f': 'mp4'}
).overwrite_output().run()
ffmpeg.output(i, output_file_name,
**{'c:v': 'libx264', 'b:v': video_bitrate, 'pass': 2, 'c:a': 'aac', 'b:a': audio_bitrate}
).overwrite_output().run()
compress()
compress_video(dst, outputLocation, 3 * 1000)