如何调整图像大小使其适合屏幕(python)

Question

我有一个机器学习面部识别脚本，它可以读取您放在同一目录中的图像，并显示带有面部标记的图像。但是，如果我给它的图像太大以适合我的屏幕，它就会放不下。我如何在 Python 脚本中调整此图像的大小以适合我的屏幕。谢谢

代码

import face_recognition as fr
import os
import cv2
import face_recognition
import numpy as np
from time import sleep


def get_encoded_faces():
    """
    looks through the faces folder and encodes all
    the faces

    :return: dict of (name, image encoded)
    """
    encoded = {}

    for dirpath, dnames, fnames in os.walk("./faces"):
        for f in fnames:
            if f.endswith(".jpg") or f.endswith(".png"):
                face = fr.load_image_file("faces/" + f)
                encoding = fr.face_encodings(face)[0]
                encoded[f.split(".")[0]] = encoding

    return encoded


def unknown_image_encoded(img):
    """
    encode a face given the file name
    """
    face = fr.load_image_file("faces/" + img)
    encoding = fr.face_encodings(face)[0]

    return encoding


def classify_face(im):
    faces = get_encoded_faces()
    faces_encoded = list(faces.values())
    known_face_names = list(faces.keys())

    face_locations = face_recognition.face_locations(img)
    unknown_face_encodings = face_recognition.face_encodings(img, face_locations)

    face_names = []
    for face_encoding in unknown_face_encodings:
        # See if the face is a match for the known face(s)
        matches = face_recognition.compare_faces(faces_encoded, face_encoding)
        name = "Unknown"

        # use the known face with the smallest distance to the new face
        face_distances = face_recognition.face_distance(faces_encoded, face_encoding)
        best_match_index = np.argmin(face_distances)
        if matches[best_match_index]:
            name = known_face_names[best_match_index]

        face_names.append(name)

        for (top, right, bottom, left), name in zip(face_locations, face_names):
            # Draw a box around the face
            cv2.rectangle(img, (left-20, top-20), (right+20, bottom+20), (255, 0, 0), 2)

            # Draw a label with a name below the face
            cv2.rectangle(img, (left-20, bottom -15), (right+20, bottom+20), (255, 0, 0), cv2.FILLED)
            font = cv2.FONT_HERSHEY_DUPLEX
            cv2.putText(img, name, (left -20, bottom + 15), font, 1.0, (255, 255, 255), 2)


    # Display the resulting image
    while True:

        cv2.imshow('Image', img)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            return face_names 


print(classify_face("test.jpg"))

如您所见，我添加了一些评论来帮助完成该过程。任何帮助将不胜感激！

Answer 1

使用matplotlib.pyplot.imshow，就没有这个问题了。 OpenCV 大部分时间都这样做，这就是为什么我更喜欢 matplotlib.

import matplotlib.pyplot as plt

plt.imshow(img)
plt.show()

Answer 2

您可以安装以下模块：

pip install screeninfo

然后使用以下代码获取屏幕尺寸：

import screeninfo

for monitor in screeninfo.get_monitors():
     print(str(monitor))

从字符串中提取尺寸并使用 cv.resize() 函数使图像适合您的屏幕。

如果您已经知道您的屏幕分辨率，另一种解决方案是添加一个简单的 if 语句，如果您的图像尺寸超过显示器尺寸，您可以将它们调整为当前尺寸。

如何调整图像大小使其适合屏幕(python)

How do I resize the image so it fits on the screen(python)

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