使用 python PIL 将图像转换为 base64

Question

以下代码抛出错误 Error with file: string argument expected, got 'bytes'

我也尝试过使用，BytesIO但它抛出了一个关于需要一种格式string而不是bytes. 非常混淆。

def im_2_b64(image):
    buffer = StringIO()
    image.save(buffer, format="JPEG")
    img_str = base64.b64encode(buffer.getvalue())
    return img_str

如何使用 python 2.7 将图像转换为 base64？

更新

Error with file: Object of type bytes is not JSON serializable
Error with file: single positional indexer is out-of-bounds

使用 BytesIO

Answer 1

这是使用 ByteIO 而不是 StringIO 的代码的简短但完整的演示。我还添加了一个函数来进行反向转换。它可以在 Python 2.6 和 3.6 上正确运行。唯一的区别是在 Python 3 中 Base64 输出是一个b字符串。

from PIL import Image
from io import BytesIO
import base64

# Convert Image to Base64 
def im_2_b64(image):
    buff = BytesIO()
    image.save(buff, format="JPEG")
    img_str = base64.b64encode(buff.getvalue())
    return img_str

# Convert Base64 to Image
def b64_2_img(data):
    buff = BytesIO(base64.b64decode(data))
    return Image.open(buff)

# Test

img = Image.new('RGB', (120, 90), 'red')
img.show()

img_b64 = im_2_b64(img)
print(img_b64)

new_img = b64_2_img(img_b64)
new_img.show()

Python 3 输出

b'/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRofHh0aHBwgJC4nICIsIxwcKDcpLDAxNDQ0Hyc5PTgyPC4zNDL/2wBDAQkJCQwLDBgNDRgyIRwhMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjL/wAARCABaAHgDASIAAhEBAxEB/8QAHwAAAQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQRBRIhMUEGE1FhByJxFDKBkaEII0KxwRVS0fAkM2JyggkKFhcYGRolJicoKSo0NTY3ODk6Q0RFRkdISUpTVFVWV1hZWmNkZWZnaGlqc3R1dnd4eXqDhIWGh4iJipKTlJWWl5iZmqKjpKWmp6ipqrKztLW2t7i5usLDxMXGx8jJytLT1NXW19jZ2uHi4+Tl5ufo6erx8vP09fb3+Pn6/8QAHwEAAwEBAQEBAQEBAQAAAAAAAAECAwQFBgcICQoL/8QAtREAAgECBAQDBAcFBAQAAQJ3AAECAxEEBSExBhJBUQdhcRMiMoEIFEKRobHBCSMzUvAVYnLRChYkNOEl8RcYGRomJygpKjU2Nzg5OkNERUZHSElKU1RVVldYWVpjZGVmZ2hpanN0dXZ3eHl6goOEhYaHiImKkpOUlZaXmJmaoqOkpaanqKmqsrO0tba3uLm6wsPExcbHyMnK0tPU1dbX2Nna4uPk5ebn6Onq8vP09fb3+Pn6/9oADAMBAAIRAxEAPwDi6KKK+ZP3EKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigAooooAKKKKACiiigD/9k='