Solve cropped image pdf import (#1068)

cps/uploader.py

@@ -20,6 +20,7 @@
 from __future__ import division, print_function, unicode_literals
 import os
 import hashlib
+import struct
 from tempfile import gettempdir
 
 from flask_babel import gettext as _
@@ -148,6 +149,23 @@ def pdf_meta(tmp_file_path, original_file_name, original_file_extension):
 def CMYKInvert(img):
     return Image.merge(img.mode,[ImageOps.invert(b.convert('L')) for b in img.split()])
 
+def tiff_header_for_CCITT(width, height, img_size, CCITT_group=4):
+    tiff_header_struct = '<' + '2s' + 'h' + 'l' + 'h' + 'hhll' * 8 + 'h'
+    return struct.pack(tiff_header_struct,
+                       b'II',  # Byte order indication: Little indian
+                       42,  # Version number (always 42)
+                       8,  # Offset to first IFD
+                       8,  # Number of tags in IFD
+                       256, 4, 1, width,  # ImageWidth, LONG, 1, width
+                       257, 4, 1, height,  # ImageLength, LONG, 1, lenght
+                       258, 3, 1, 1,  # BitsPerSample, SHORT, 1, 1
+                       259, 3, 1, CCITT_group,  # Compression, SHORT, 1, 4 = CCITT Group 4 fax encoding
+                       262, 3, 1, 0,  # Threshholding, SHORT, 1, 0 = WhiteIsZero
+                       273, 4, 1, struct.calcsize(tiff_header_struct),  # StripOffsets, LONG, 1, len of header
+                       278, 4, 1, height,  # RowsPerStrip, LONG, 1, lenght
+                       279, 4, 1, img_size,  # StripByteCounts, LONG, 1, size of image
+                       0  # last IFD
+                       )
 
 def pdf_preview(tmp_file_path, tmp_dir):
     if use_generic_pdf_cover:
@@ -157,12 +175,14 @@ def pdf_preview(tmp_file_path, tmp_dir):
             try:
                 input1 = PdfFileReader(open(tmp_file_path, 'rb'), strict=False)
                 page0 = input1.getPage(0)
+                mediaBox = page0['/MediaBox']
+                box = page0['/CropBox'] if '/CropBox' in page0 else mediaBox
                 xObject = page0['/Resources']['/XObject'].getObject()
 
                 for obj in xObject:
                     if xObject[obj]['/Subtype'] == '/Image':
                         size = (xObject[obj]['/Width'], xObject[obj]['/Height'])
-                        data = xObject[obj]._data # xObject[obj].getData()
+                        data = xObject[obj]._data
                         mode = "P"
                         if xObject[obj]['/ColorSpace'] == '/DeviceRGB':
                             mode = "RGB"
@@ -180,20 +200,52 @@ def pdf_preview(tmp_file_path, tmp_dir):
                                 img = open(cover_file_name, "wb")
                                 img.write(data)
                                 img.close()
+                                # Post processing
+                                img2 = Image.open(cover_file_name)
+                                width, height = img2.size
                                 if mode == 'CMYK':
-                                    img2 = Image.open(cover_file_name)# .convert('RGB')
                                     img2 = CMYKInvert(img2)
-                                    img2.save(cover_file_name)
+                                img2 = img2.crop((box[0]/mediaBox[2]*width,
+                                                  box[1]/mediaBox[3]*height,
+                                                  box[2]/mediaBox[2]*width,
+                                                  box[3]/mediaBox[3]*height))
+                                img2.save(cover_file_name)
                                 return cover_file_name
                             elif xObject[obj]['/Filter'] == '/JPXDecode':
                                 cover_file_name = os.path.splitext(tmp_file_path)[0] + ".cover.jp2"
                                 img = open(cover_file_name, "wb")
                                 img.write(data)
                                 img.close()
+                                # Post processing
+                                img2 = Image.open(cover_file_name)
+                                width, height = img2.size
                                 if mode == 'CMYK':
-                                    img2 = Image.open(cover_file_name)# .convert('RGB')
                                     img2 = CMYKInvert(img2)
-                                    img2.save(cover_file_name)
+                                img2 = img2.crop((box[0]/mediaBox[2]*width,
+                                                  box[1]/mediaBox[3]*height,
+                                                  box[2]/mediaBox[2]*width,
+                                                  box[3]/mediaBox[3]*height))
+                                img2.save(cover_file_name)
+                                return cover_file_name
+                            elif xObject[obj]['/Filter'] == '/CCITTFaxDecode':
+                                if xObject[obj]['/DecodeParms']['/K'] == -1:
+                                    CCITT_group = 4
+                                else:
+                                    CCITT_group = 3
+                                width = xObject[obj]['/Width']
+                                height = xObject[obj]['/Height']
+                                img_size = len(data)
+                                tiff_header = tiff_header_for_CCITT(width, height, img_size, CCITT_group)
+                                cover_file_name_tiff = os.path.splitext(tmp_file_path)[0] + obj[1:] + '.tiff'
+                                cover_file_name = os.path.splitext(tmp_file_path)[0] + obj[1:] + '.jpg'
+                                img = open(cover_file_name_tiff, "wb")
+                                img.write(tiff_header + data)
+                                img.close()
+                                # Post processing
+                                img2 = Image.open(cover_file_name_tiff)
+                                if img2.mode == '1':
+                                    img2 = ImageOps.invert(img2.convert('RGB'))
+                                img2.save(cover_file_name)
                                 return cover_file_name
                         else:
                             img = Image.frombytes(mode, size, data)