python pillow image manipulate

 

from PIL import Image

im = Image.open('test.jpg')

im.save('test.png', format='PNG')

img = img.convert('RGB') 

img.save('image_compressed.jpg', quality=50, optimize=True)

ou can also use other libraries and methods to compress images in Python, 

such as zlib, pngquant, or GraphicsMagick 

img = img.resize((200, 150), Image.LANCZOS)

The resampling filter determines how the pixels are interpolated when 
resizing the image. Some of the available filters are Image.NEAREST, 
Image.BILINEAR, Image.BICUBIC, and Image.LANCZOS. If you omit the 
filter, or if the image has mode “1” or “P”, it is set to Image.NEAREST 
by default. Otherwise, the default filter is Image.BICUBIC.

 new_file_size = original_file_size * ((new_width / original_width) * 
(new_height / original_height)) * (new_bit_depth / original_bit_depth)  

https://stackoverflow.com/questions/33901299/formula-to-calculate-file-size-of-jpeg-image-after-resizing