Question

希望您做得很好，我正在尝试提供“无头”摄像头服务，但是camera._camera.bind()似乎无法正常运行，除非它是LayOut的一部分，这是“带有GUI的几乎最小的摄像头示例”，它是工作：

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.boxlayout import BoxLayout
import time
import PIL
from kivy.uix.camera import Camera

Builder.load_string('''
<CameraClick>:
    orientation: 'vertical'
    ToggleButton:
        text: 'Play'
        on_press: root.camera.play = not root.camera.play
        size_hint_y: None
        height: '48dp'
    Button:
        text: 'Capture'
        size_hint_y: None
        height: '48dp'
        on_press: root.capture()
''')


class CameraClick(BoxLayout):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self.camera = Camera(play=False, resolution=(640, 480))
        self.camera._camera.bind(on_texture=self.capture)

    def capture(self, instance=None):
        '''
        Function to capture the images and give them the names
        according to their captured time and date.
        '''
        camera = instance or self.camera
        print(type(camera), camera)
        texture = camera.texture
        image_data = texture.pixels
        size = texture.size
        fmt = texture.colorfmt.upper()
        timestr = time.strftime("%Y%m%d_%H%M%S")
        pil_image = PIL.Image.frombytes(mode=fmt, size=size, data=image_data)
        pil_image.save("IMG_{}.png".format(timestr))
        print("Captured")


class TestCamera(App):

    def build(self):
        return CameraClick()


TestCamera().run()

这是我在没有GUI的情况下无法正常工作的最小示例：

from kivy.uix.camera import Camera
import time
import PIL

def capture(instance):
    camera = instance
    texture = camera.texture
    image_data = texture.pixels
    size = texture.size
    fmt = texture.colorfmt.upper()
    timestr = time.strftime("%Y%m%d_%H%M%S")
    pil_image = PIL.Image.frombytes(mode=fmt, size=size, data=image_data)
    pil_image.save("IMG_{}.png".format(timestr))
    print("Captured")

c = Camera(play=False, resolution=(640, 480))
c._camera.bind(on_texture=capture)
c.play = True
print("Taking 5 seconds of photos...")
sleep(5)
print("Turning off taking photos")
c.play = False

因此，在GUI示例中，当我单击播放时，这很有效，这很简单，camera.play = True，而当我在没有GUI的最小Camera上执行camera.play = True时，将永远不会调用捕获功能。 / p>

我在做什么错了？

编辑：来自Matham（请参阅github评论）：看来您正在阻止kivy主线程。您无法以“无头”模式运行kivy，因为gui始终需要运行，并且主线程无法被阻止，https://github.com/kivy/kivy/issues/6272#issuecomment-486489264

所以我认为我需要使用pyjnius实现摄像头

如何在无头模式下运行相机Kivy应用程序？

0 个答案: