将 WandImageObject 转换为 QPixmap

Question

我正在使用 wand.image 库将 PdfPages 转换为图像。
我需要将它们存储到缓存中而不是将它们存储在本地，但我无法弄清楚如何将此 WandImage-Object 转换为像素图。我已经阅读了 wand.image 的文档并进行了大量研究，但我自己无法解决问题..

当我将代码保存在本地时，我的代码运行非常好：

def pdf_to_jpeg(self, pdf_path):
    list_of_images = []
    wand_image_pdf = WI(filename=pdf_path, resolution=20)
    wand_image_jpegs = wand_image_pdf.convert("jpeg")
    for page_number, wand_image_jpeg in enumerate(wand_image_jpegs.sequence):
        jpeg = WI(image=wand_image_jpeg)
        jpeg.save(filename="../output/{0}.jpeg".format(str(page_number)))
        list_of_images.append("../output/{0}.jpeg".format(str(page_number)))
    return list_of_images

但是使用我的新代码：

def pdf_to_jpeg(self, pdf_path):
    list_of_images = []
    wand_image_pdf = WI(filename=pdf_path, resolution=20)
    wand_image_jpegs = wand_image_pdf.convert("jpeg")
    for page_number, wand_image_jpeg in enumerate(wand_image_jpegs.sequence):
        jpeg = WI(image=wand_image_jpeg)
        list_of_images.append(jpeg)
    return list_of_images

我得到一个错误：

QImage::QImage(), XPM is not supported
Traceback (most recent call last):

File "/Users/darjusch.schrand/PycharmProjects/PdfConverter/pdf_converter/main.py", line 33, in setup
    self.push_button_to_image = self.logic.create_push_button(self.list_of_images)

File "/Users/darjusch.schrand/PycharmProjects/PdfConverter/pdf_converter/logic/logic.py", line 21, in create_push_button
    pixmap = QPixmap(pic)
TypeError: The argument must be a sequence of strings.

最小工作示例：

from PySide2.QtGui import QPixmap, QIcon
from PySide2.QtCore import QSize
from PySide2.QtWidgets import QPushButton

class Logic:

def create_push_button(list_of_images):
    push_button_to_image = {}
    for pic in list_of_images:
        push_button = QPushButton()
        pixmap = QPixmap(pic)
        button_icon = QIcon(pixmap)
        push_button.setIcon(button_icon)
        push_button.setIconSize(QSize(100, 100))
        push_button.setCheckable(True)
        push_button_to_image[push_button] = pic
    return push_button_to_image

def pdf_to_jpeg(pdf_path):
    list_of_images = []
    wand_image_pdf = WI(filename=pdf_path, resolution=20)
    wand_image_jpegs = wand_image_pdf.convert("jpeg")
    for page_number, wand_image_jpeg in enumerate(wand_image_jpegs.sequence):
        jpeg = WI(image=wand_image_jpeg)
        list_of_images.append(jpeg)
    return list_of_images

pdf_to_jpeg("example.pdf")

example.pdf

Answer 1

顺序是：

使用 make_blob().
使用 loadFromData() 方法将字节转换为 QImage。
使用 fromImage() 方法将 QImage 转换为 QPixmap。

from wand.image import Image

from PySide2 import QtCore, QtGui, QtWidgets


def pdf_to_qimages(pdf_path, resolution=200, fmt="png"):
    qimages = []
    with Image(filename=pdf_path, resolution=resolution) as pdf_im:
        for page in pdf_im.sequence:
            with Image(page) as page_image:
                qimage = QtGui.QImage()
                data = page_image.make_blob(format=fmt)
                qimage.loadFromData(data)
                qimages.append(qimage)
    return qimages


if __name__ == "__main__":
    import os
    import sys

    app = QtWidgets.QApplication(sys.argv)
    current_dir = os.path.dirname(os.path.realpath(__file__))
    pdf_path = os.path.join(current_dir, "sample.pdf")

    qimages = pdf_to_qimages(pdf_path, resolution=20, fmt="jpeg")

    w = QtWidgets.QListWidget(
        viewMode=QtWidgets.QListWidget.IconMode,
        resizeMode=QtWidgets.QListWidget.Adjust,
        movement=QtWidgets.QListView.Static,
        iconSize=QtCore.QSize(200, 400),
    )
    for qimage in qimages:
        pixmap = QtGui.QPixmap.fromImage(qimage)

        it = QtWidgets.QListWidgetItem()
        it.setIcon(QtGui.QIcon(pixmap))
        w.addItem(it)
    w.resize(640, 480)
    w.show()
    sys.exit(app.exec_())

将 WandImageObject 转换为 QPixmap

Convert WandImageObject into QPixmap

python

python-3.x

wand

pyside2