import gi

gi.require_version("Gtk", "3.0")

from gi.repository import Gtk, Gdk
from gi.repository.GdkPixbuf import Pixbuf 

# 读取图片, 返回图片像素数据
filename = 'xxx.png'
pixbuf = Pixbuf.new_from_file(filename)

# 得到这个对象, 就是可以传给前端的, 

image = {
  "width": pixbuf.get_width(),
  "height": pixbuf.get_height(),
  "colorspace": pixbuf.get_colorspace(),
  "has_alpha": pixbuf.	get_has_alpha(),
  "bits_per_sample": pixbuf.get_bits_per_sample(),
  "rowstride": pixbuf.get_rowstride(),
  "filepath": filename,
  "bytes": list(pixbuf.get_pixels())
}

# scripts = 'native.$emit("' + callback + '",' + json.dumps(image) + ')'

# 倒扣到前端传回来的数据, 调用 Pixbuf.new_from_data 可转回 Pixbuf对象
pixbuf = Pixbuf.new_from_data(
  data = bytes(image['bytes']),
  colorspace = image['colorspace'],
  has_alpha = image['has_alpha'],
  bits_per_sample = image['bits_per_sample'],
  width = image['width'],
  height = image['height'],
  rowstride = image['rowstride']
)