1""" 

2@file 

3@brief image helpers 

4""" 

5import os 

6from PIL import Image 

7 

8 

9def collate_images(imgs, final=None): 

10 """ 

11 Collates all images horizontally in one image (if not None --> image name). 

12 

13 @param imgs list of image files 

14 @param final final image (or None not to save) 

15 @return final image (PIL object) 

16 

17 It uses the module `Pillow <http://python-imaging.github.io/>`_. 

18 """ 

19 ims = [Image.open(pic) for pic in imgs] 

20 size = [_.size for _ in ims] 

21 fsize = (sum([_[0] for _ in size]), 

22 max([_[1] for _ in size])) 

23 blank = Image.new("RGB", fsize, (255, 255, 255)) 

24 s = 0 

25 for im in ims: 

26 blank.paste(im, (s, 0)) 

27 s += im.size[0] 

28 if final is not None: 

29 blank.save(final) 

30 return blank 

31 

32 

33def convert_image(imgs, ext, dest=None, fLOG=None): 

34 """ 

35 Converts an image or a list of images into a different format. 

36 

37 @param imgs list of images (filenames) 

38 @param dest destination folder, if None, the image is saved beside the orginal one 

39 @param ext new format 

40 @param fLOG logging function 

41 @return list of written images 

42 """ 

43 if isinstance(imgs, str): 

44 imgs = [imgs] 

45 if not isinstance(ext, str): 

46 raise TypeError("ext must a string") 

47 if len(ext) == 0: 

48 raise ValueError("ext must not be empty") 

49 if ext.startswith("."): 

50 raise ValueError("ext must not start with a point '{0}'".format(ext)) 

51 saved = [] 

52 for img in imgs: 

53 if fLOG is not None: 

54 fLOG("[convert_image]", img) 

55 obj = Image.open(img) 

56 if dest is None: 

57 folder = os.path.dirname(img) 

58 else: 

59 folder = dest 

60 name = os.path.splitext(os.path.split(img)[-1])[0] 

61 new_name = os.path.join(folder, name + "." + ext) 

62 obj.save(new_name) 

63 saved.append(new_name) 

64 return saved