python2.7 PIL 图片收缩并转码base64
需求：将图片转为base64，最大允许图片大小600px*400px
1 def changeimgtobase64(img_url, max_width=600, max_height=400, resize=True): 2 """ 3 4 :param img_url: 图片地址 5 :param max_width: 长边 6 :param max_height: 短边 7 :param resize: 是否改变大小 8 :return: 9 """ 10 if img_url.startswith('/'): 11 img_url = img_url[1:] 12 img_url = os.path.join(settings.ROOT_PATH, img_url) 13 rotate = False # 是否短边为宽 14 result = '' 15 try: 16 img = Image.open(img_url) 17 width, height = img.size 18 if resize: 19 # width, height = img.size 20 if width < height: 21 # 使图片长边为宽 22 rotate = True 23 width, height = height, width 24 if width > max_width or height > max_height: 25 width = min([width, max_width]) 26 height = min([height, max_height]) 27 if rotate: 28 img = img.resize((height, width), Image.ANTIALIAS) 29 else: 30 img = img.resize((width, height), Image.ANTIALIAS) 31 else: 32 while width*height > 1024 * 1024 * 2: # 图片像素点大于2M就缩小0.9，直至小于2M 33 width, height = int(width*0.9), int(height*0.9) 34 log.debug('%s:%s,%s' % (u'图片缩小至', width,height)) 35 img = img.resize((width, height), Image.ANTIALIAS) 36 37 img_buffer = io.BytesIO() 38 if img_url.find('jpeg') == -1: 39 # 将png等非jpg格式转为jpg 40 img = img.convert("RGB") 41 img.save(img_buffer, format='JPEG') 42 byte_data = img_buffer.getvalue() 43 img_buffer.close() 44 base64_data = base64.b64encode(byte_data) 45 s = base64_data.decode() 46 result = 'data:image/jpg;base64,%s' % s 47 except Exception, e: 48 exc_type, exc_obj, exc_tb = sys.exc_info() 49 alertmsg = u'%s %s Exception. %s:%s' % (platform.node(), exc_tb.tb_lineno, sys._getframe().f_code.co_name, e) 50 log.error(alertmsg) 51 return result
