summaryrefslogtreecommitdiffstats
path: root/konq-plugins/imagerotation/orient.py
blob: f7a0047877caa0d716fcbab2974d8260eab6f64d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
#! /usr/bin/env python
import os
import sys
import exif

def compose(delta, old):
  map=[0, 4, 2, 6, 5, 1, 7, 3]
  unmap=[1, 6, 3, 8, 2, 5, 4, 7]
  x = map[delta-1]
  y = map[old-1]
  z = ((x^y)&4) + ((y+(x&3)*(((y&4)>>1)+1))&3)
  return unmap[z]

def deg2o(d):
  map={90:6, 270:8, 180:3}
  if d in map:
    return map[d]
  else:
    return 0

if len(sys.argv) < 2:
  print('Usage: %s [[+]orientnum] file\n' % sys.argv[0])
  sys.exit(1)
try:
  if len(sys.argv) == 2:
    filename=sys.argv[1]
    file=open(filename, 'rb');
  else:
    filename=sys.argv[2]
    mod=sys.argv[1]
    fd = os.open(filename, os.O_RDWR)
    file=os.fdopen(fd,'rb')
    # check file exists and is readable
    file.read(1)
    file.seek(0,0)
except:
  print('Cannot open', filename)
  sys.exit(1)

tags=exif.process_file(file,0,1)
if not tags:
  print('no EXIF information in', filename)
  sys.exit(1)
if 'Exif Offset' not in tags \
    or 'Image Orientation' not in tags:
  print('cannot get orientation info in', filename)
  sys.exit(1)

exifp = tags['Exif Offset']
endian = tags['Exif Endian']
tagp = tags['Image Orientation'].field_offset

orientp = exifp + tagp

if endian == 'M': # MM byte order
  orientp += 1

file.seek(orientp)
o = ord(file.read(1))

if o < 1 or o > 8:
  print('orientation out of range', o)
  sys.exit(1)

if len(sys.argv) == 2:
  print('orientation is', o)
  sys.exit(0)

try:
  if mod[0] == '+':
    deltao = int(mod)
    if 1 <= deltao and deltao <= 8:
      newo = compose(deltao, o)
    elif deg2o(deltao) != 0:
      newo = compose(deg2o(deltao), o)
    else:
      print('cannot understand orientation modification', mod)
      sys.exit(1) # it will still hit the except ... how to fix?
  else:
    newo = int(mod)
except:
  print('expected numeric orientation and got',mod)
  sys.exit(1)

if newo < 1 or newo > 8:
  newo = deg2o(newo)
  if newo == 0:
    print('cannot understand orientation', deltao)
    sys.exit(1)

os.lseek(fd,orientp,0)
os.write(fd,chr(newo))

# Thumbnail orientation :
thumb_ifdp = 0
if 'Thumbnail Orientation' in tags:
  thumb_tagp = tags['Thumbnail Orientation'].field_offset
  thumb_orientp = exifp + thumb_tagp
  if endian == 'M': # MM byte order
    thumb_orientp += 1
  os.lseek(fd,thumb_orientp,0)
  os.write(fd,chr(newo))

print('orientation changed from', o, 'to', newo)