Question

想知道是否有人可以帮我解决一些简单的问题。我正在运行一个将WAV文件转换为PNG的脚本，问题是我无法加载超过1秒的WAV文件。

我需要更改imageSize = math.sqrt（44100）以增加允许的图像大小，但我不确定如何去做。我想加载一个60秒的WAV文件。

我已经尝试过math.sqrt（44100 * 60）但是我仍然得到一个55KB的输出PNG。（60秒的音频文件是5MB）代码：

from PIL import Image
import wave, struct, sys, math

##
# Collect input
##
if sys.argv[1][-4:] != '.wav':
    sys.exit("First argument should be a .wav file")

if sys.argv[2][-4:] != '.png':
    sys.exit("Second argument should be a .png file")

##
# Conversion:
##

# Wave file needs to be 16 bit mono
waveFile = wave.open(sys.argv[1], 'r')

if waveFile.getnchannels() != 1:
    sys.exit("ERROR: The wave file should be single channel (mono)")

if waveFile.getframerate() != 44100:
    sys.exit("ERROR: The samplerate should be 44,100")

imageRgbArray = list()

waveLength = waveFile.getnframes()

# Create the image size (based on the length)
imageSize = math.sqrt(44100)

# Loop through the wave file
for i in range(0, 44100):

    # Try to read frame, if not possible fill with 0x0
    try:
        waveData = waveFile.readframes(1)
        data = struct.unpack("<h", waveData) # This loads the wave bit
        convertedData = int(data[0]) + 32768 # This adds 16bit/2 (=32768) to the data
    except:
        convertedData = 0
        pass

    # This converts the number into a hex value.
    convertedDataHex = hex(convertedData)

    # convert the value to a string and strips first two characters
    hexString = str(convertedDataHex)[2:]

    # Check how much the string should be prefixed to get the color hex length (= 6 char)
    count = 6 - len(hexString)

    # Prefix with a zero
    while (count > 0):
        hexString = "0" + hexString
        count -= 1

    # Convert into RGB value
    rgbData = tuple(int(hexString[i:i + 6 // 3], 16) for i in range(0, 6, 6 // 3)) # Convert to RGB data

    # Add the RGB value to the image array
    imageRgbArray.append(rgbData)

# Create new image
im = Image.new('RGB', (int(imageSize), int(imageSize)))

# Add image data
im.putdata(imageRgbArray)

# Save image
im.save(sys.argv[2])

完整的项目（不是我的）： https://github.com/bobvanluijt/audio-convolutional-neural-network

Answer 1

我通过更改这几行来实现它，sqrt的问题是它给浮点数并且向下舍入，因此图像没有足够的像素，我们可以通过使用ceiling函数来防止它。

...
waveLength = waveFile.getnframes()

# Create the image size (based on the length)
imageSize = math.ceil(math.sqrt(waveLength))

# Loop through the wave file
for i in range(waveLength):
    ...

这种方法的好处是我们不再受限于给定比特率的样本，因此您可以删除。

if waveFile.getframerate() != 44100:
    sys.exit("ERROR: The samplerate should be 44,100")

如何更改imagesize以允许更长的音频（wav到png）

1 个答案: