Switch from pafy to streamlink for youtube support (#45)

pafy has fallen way out of date and no longer works. streamlink can also be used to fetch HLS (HTTP Live Streaming) URLs for youtube videos. Seems to work fine on streams that pafy did not work with.

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "stream"
-version = "0.5.0"
+version = "0.5.1"
 description = "Groundlight Stream Processor - Container for analyzing video using RTSP etc"
 readme = "README.md"
 requires-python = ">=3.10"
@@ -11,8 +11,7 @@ dependencies = [
     "numpy<2.0.0",
     "opencv-python-headless>=4.10.0.84",
     "PyYAML==6.0.2",
-    "youtube-dl==2021.12.17",
-    "pafy>=0.5.5"
+    "streamlink==7.0.0",
 ]
 
 [project.optional-dependencies]

src/stream/grabber.py

@@ -10,7 +10,7 @@
 
 import cv2
 import numpy as np
-import pafy
+import streamlink
 
 logger = logging.getLogger("groundlight.stream")
 
@@ -194,17 +194,23 @@ class YouTubeFrameGrabber(FrameGrabber):
 
     def __init__(self, stream=None):
         self.stream = stream
-        self.video = pafy.new(self.stream)
-        self.best_video = self.video.getbest(preftype="mp4")
+        streams = streamlink.streams(self.stream)
+        if "best" not in streams:
+            raise ValueError("No available HLS stream for this live video.")
+        self.best_video = streams["best"]
+
         self.capture = cv2.VideoCapture(self.best_video.url)
         logger.debug(f"initialized video capture with backend={self.capture.getBackendName()}")
         if not self.capture.isOpened():
             raise ValueError(f"could not initially open {self.stream=}")
         self.capture.release()
 
     def reset_stream(self):
-        self.video = pafy.new(self.stream)
-        self.best_video = self.video.getbest(preftype="mp4")
+        streams = streamlink.streams(self.stream)
+        if "best" not in streams:
+            raise ValueError("No available HLS stream for this live video.")
+        self.best_video = streams["best"]
+
         self.capture = cv2.VideoCapture(self.best_video.url)
         logger.debug(f"initialized video capture with backend={self.capture.getBackendName()}")
         if not self.capture.isOpened():