Question

我有一个pdf文件，我需要扫描并提取图像并将其拖放到指定的文件夹中。

我尝试了以下线程和网站：

Extract images from PDF without resampling, in python?

https://nedbatchelder.com/blog/200712/extracting_jpgs_from_pdfs.html

底部不运行。 SO线程运行，但是当应该在13左右时，文件夹中没有图像显示。下面是我正在使用的代码：

import sys
import PyPDF2
import struct
from PIL import Image

def tiff_header_for_CCITT(width, height, img_size, CCITT_group=4):
    tiff_header_struct = '<' + '2s' + 'h' + 'l' + 'h' + 'hhll' * 8 + 'L'
    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
                       )

pdf_filename = "C:\\Users\\jordan.howell\\Desktop\\191008062029-5002701055.pdf"
pdf_file = open(pdf_filename, 'rb')
cond_scan_reader = PyPDF2.PdfFileReader(pdf_file)
for i in range(0, cond_scan_reader.getNumPages()):
    page = cond_scan_reader.getPage(i)
    xObject = page['/Resources']['/XObject'].getObject()
    for obj in xObject:
        if xObject[obj]['/Subtype'] == '/Image':
            """
            The  CCITTFaxDecode filter decodes image data that has been encoded using
            either Group 3 or Group 4 CCITT facsimile (fax) encoding. CCITT encoding is
            designed to achieve efficient compression of monochrome (1 bit per pixel) image
            data at relatively low resolutions, and so is useful only for bitmap image data, not
            for color images, grayscale images, or general data.

            K < 0 --- Pure two-dimensional encoding (Group 4)
            K = 0 --- Pure one-dimensional encoding (Group 3, 1-D)
            K > 0 --- Mixed one- and two-dimensional encoding (Group 3, 2-D)
            """
            if 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']
                data = xObject[obj]._data  # sorry, getData() does not work for CCITTFaxDecode
                img_size = len(data)
                tiff_header = tiff_header_for_CCITT(width, height, img_size, CCITT_group)
                img_name = obj[1:] + '.tiff'
                with open(img_name, 'wb') as img_file:
                    img_file.write("C:\\Users\\jordan.howell\\Desktop\\pdf_images\\" + tiff_header + data + ".jpg")


pdf_file.close()

有人看到我的代码有问题的原因，为什么它不会删除图像？

使用python从PDF提取图片

0 个答案: