Raspberry Pi 3 Model B + Camera V2.1 picamera2 web.py 失敗

前回は、libcamera-stillで静止画が撮れるところまでを記録した。 次に、カメラで撮影した画像を、外から見られるようにしたくなった。動画として見られるとよいのだが、まずは静止画がみられることを目標にした。 まずは、pythonのpicamera2とwebpyで、あるurlにアクセスしたら静止画を撮ってそれを返すプログラムを作ることにした。 1. picamera2 このページを参考に環境を構築した。 https://github.com/raspberrypi/picamera2

1. sudo apt install -y python3-pyqt5 python3-opengl
2. sudo apt install -y python3-picamera2 --no-install-recommends

2. web.py

1. pip install web.py==0.61
"==0.61"の意味はわかってない。
2. app.py
import web

import io

import time

from picamera2 import Picamera2

urls = (

   "/",

   "index"

)

class index:

   def __init__(self):

     self.cam = Picamera2()

     self.capture_config = self.cam.create_still_configuration()

     self.cam.configure(self.cam.create_preview_configuration())

   def GET(self):

     self.cam.start()

     time.sleep(1)

     data = io.BytesIO()

     self.cam.capture_file(data, format='jpeg')

     self.cam.stop()

     return(data.getvalue())

     #image = open("/home/python/Pictures/camera.jpg", "rb").read()

     #return image

if __name__ == '__main__':

   app = web.application(urls, globals())

   app.run()

ファイルに保存してからそれを返すのではなく、メモリ中にjpgイメージを作ってそれをかえすことで、ディスクの寿命を延ばす作戦。
1. 実行
最初のアクセスには、正しく静止画を返してくれたが、2回目のアクセスで落ちる。
$ python app.py

http://0.0.0.0:8080/

[1:43:46.506893147] [2163] INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f

[1:43:46.598907128] [2180] WARN RPI vc4.cpp:383 Mismatch between Unicam and CamHelper for embedded data usage!

[1:43:46.600689216] [2180] INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx219@10 to Unicam device /dev/media3 and ISP device /dev/media1

[1:43:46.600802029] [2180] INFO RPI pipeline_base.cpp:1101 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml'

[1:43:46.616782902] [2163] INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 640x480-SBGGR10_CSI2P

[1:43:46.618274573] [2180] INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 640x480-SBGGR10_1X10 - Selected unicam format: 640x480-pBAA

192.168.10.23:56710 - - [09/Oct/2023 13:40:27] "HTTP/1.1 GET /" - 200 OK

192.168.10.23:56710 - - [09/Oct/2023 13:40:27] "HTTP/1.1 GET /favicon.ico" - 404 Not Found

[1:45:28.564968768] [2165] ERROR Camera camera.cpp:525 Camera in Configured state trying acquire() requiring state Available

Camera __init__ sequence did not complete.

Traceback (most recent call last):

File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 242, in __init__ self._open_camera() File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 446, in _open_camera self.camera.acquire() RuntimeError: Failed to acquire camera: Device or resource busy

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

File "/home/python/.local/lib/python3.9/site-packages/web/application.py", line 280, in process

return self.handle()

File "/home/python/.local/lib/python3.9/site-packages/web/application.py", line 271, in handle

return self._delegate(fn, self.fvars, args)

File "/home/python/.local/lib/python3.9/site-packages/web/application.py", line 514, in _delegate

return handle_class(cls)

File "/home/python/.local/lib/python3.9/site-packages/web/application.py", line 491, in handle_class

tocall = getattr(cls(), meth)

File "/home/python/Documents/prog/webpy/app.py", line 13, in __init__

self.cam = Picamera2()

File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 254, in __init__

raise RuntimeError("Camera __init__ sequence did not complete.")

RuntimeError: Camera __init__ sequence did not complete.

192.168.10.23:56740 - - [09/Oct/2023 13:42:08] "HTTP/1.1 GET /" - 500 Internal Server Error

次回は、これの修正を試みる。