Add initial support for ffmpeg

Fixes HP Spectre x360 13t IR camera issue. The IR camera is detected by OpenCV but fails to work properly. FFMPEG works using /dev/video2 device. Added an ffmpeg class that mimics the behavior 
 and currently used functions of opencv.

src/cli/add.py

@@ -77,8 +77,15 @@ insert_model = {
 	"data": []
 }
 
-# Open the camera
-video_capture = cv2.VideoCapture(config.get("video", "device_path"))
+if config.get("video", "recording_plugin") == "ffmpeg":
+	from ffmpeg_reader import ffmpeg_reader
+
+	# Set the capture source for ffmpeg
+	video_capture = ffmpeg_reader(config.get("video", "device_name"), config.get("video", "device_format"), 10)
+
+else:
+	# Start video capture on the IR camera
+	video_capture = cv2.VideoCapture(config.get("video", "device_path"))
 
 # Force MJPEG decoding if true
 if config.getboolean("video", "force_mjpeg"):

src/compare.py

@@ -56,8 +56,15 @@ for model in models:
 # Add the time needed to start the script
 timings.append(time.time())
 
-# Start video capture on the IR camera
-video_capture = cv2.VideoCapture(config.get("video", "device_path"))
+if config.get("video", "recording_plugin") == "ffmpeg":
+	from ffmpeg_reader import ffmpeg_reader
+
+	# Set the capture source for ffmpeg
+	video_capture = ffmpeg_reader(config.get("video", "device_name"), config.get("video", "device_format"), 10)
+
+else:
+	# Start video capture on the IR camera
+	video_capture = cv2.VideoCapture(config.get("video", "device_path"))
 
 # Force MJPEG decoding if true
 if config.getboolean("video", "force_mjpeg"):

src/config.ini

@@ -22,6 +22,21 @@ dismiss_lockscreen = false
 disabled = false
 
 [video]
+#
+# opencv or ffmpeg.  Choose ffmpeg if your IR device is a grayscale only.
+# Run this: v4l2-ctl -d /dev/video2 --list-formats
+recording_plugin = opencv
+
+#
+# format to use for ffmpeg. Could be vfwcap or v4l2 or some other thing...
+#
+device_format = v4l2
+
+#
+# device name if using ffmpeg. ex: /dev/video2
+#
+device_name = none
+
 # The certainty of the detected face belonging to the user of the account
 # On a scale from 1 to 10, values above 5 are not recommended
 certainty = 3.5

src/ffmpeg_reader.py

@@ -0,0 +1,113 @@
+import ffmpeg
+import numpy
+from cv2 import CAP_PROP_FRAME_WIDTH
+from cv2 import CAP_PROP_FRAME_HEIGHT
+from cv2 import CAP_PROP_FOURCC
+import sys
+
+import json
+#import subprocess
+#from ._run import Error
+from subprocess import Popen, PIPE
+
+
+class ffmpeg_reader:
+	""" This class was created to look as similar to the openCV features used in Howdy as possible for overall code cleanliness. """
+
+	# Init
+	def __init__(self, device_name, device_format, numframes):
+		self.device_name = device_name
+		self.device_format = device_format
+		self.numframes = numframes
+		self.video = ()
+		self.num_frames_read = 0
+		self.height = 0
+		self.width = 0
+		self.init_camera = True
+		self.force_jpeg = 0
+
+	def set(self, prop, setting):
+		""" Setter method for height and width """
+		if prop == CAP_PROP_FRAME_WIDTH:
+			self.width = setting
+		elif prop == CAP_PROP_FRAME_HEIGHT:
+			self.height = setting
+		elif prop == CAP_PROP_FOURCC:
+			self.force_jpeg = setting
+
+
+	def get(self, prop):
+		""" Getter method for height and width """
+		if prop == CAP_PROP_FRAME_WIDTH:
+			return self.width
+		elif prop == CAP_PROP_FRAME_HEIGHT:
+			return self.height
+		elif prop == CAP_PROP_FOURCC:
+			return self.force_jpeg
+			
+	def probe(self):
+		""" Probe the video device to get height and width info """
+		probe = ffmpeg.probe(self.device_name)
+
+		if self.get(CAP_PROP_FRAME_WIDTH) == 0 or self.get(CAP_PROP_FRAME_WIDTH) > int(probe['streams'][0]['width']):
+			self.set(CAP_PROP_FRAME_WIDTH, probe['streams'][0]['width'])
+		if self.get(CAP_PROP_FRAME_HEIGHT) == 0  or self.get(CAP_PROP_FRAME_HEIGHT) > int(probe['streams'][0]['height']):
+			self.set(CAP_PROP_FRAME_HEIGHT, probe['streams'][0]['height'])
+
+	def record(self, numframes):
+		""" Record a video, saving it to self.video array for processing later """
+
+		# Eensure we have set our width and height before we record, otherwise our numpy call will fail
+		if self.get(CAP_PROP_FRAME_WIDTH) == 0 or self.get(CAP_PROP_FRAME_HEIGHT) == 0:
+			self.probe()
+
+		# Ensure num_frames_read is reset to 0
+		self.num_frames_read = 0
+
+		stream, ret = (
+			ffmpeg
+			.input(self.device_name, format=self.device_format)
+			.output('pipe:', format='rawvideo', pix_fmt='rgb24', vframes=numframes)
+			.run(capture_stdout=True, quiet=True)
+		)
+		self.video = (
+			numpy
+			.frombuffer(stream, numpy.uint8)
+			.reshape([-1, self.width, self.height, 3])
+		)
+
+
+	def read(self):
+		""" Read a sigle frame from the self.video array. Will record a video if array is empty. """
+
+		# First time we are called, we want to initialize the camera by probing it, to ensure we have height/width
+		# and then take numframes of video to fill the buffer for faster recognition.
+		if self.init_camera:
+			self.init_camera = False
+			self.set(CAP_PROP_FRAME_HEIGHT, 352)
+			self.set(CAP_PROP_FRAME_WIDTH, 352)
+			self.video = ()
+			self.record(self.numframes)
+			return 0, self.video
+
+		# If we are called and self.video is empty, we should record self.numframes to fill the video buffer
+		if self.video == ():
+			self.record(self.numframes)
+
+		# If we've read max frames, but still are being requested to read more, we simply record another batch.
+		# Note, the video array is 0 based, so if numframes is 10, we must subtract 1 or run into an array index
+		# error.
+		if self.num_frames_read >= (self.numframes - 1):
+			self.record(self.numframes)
+
+		# Add one to num_frames_read. If we were at 0, that's fine as frame 0 is almost 100% going to be black
+		# as the IR lights aren't fully active yet anyways. Saves us one iteration in the while loop ni add/compare.py.
+		self.num_frames_read += 1
+
+		# Return a single frame of video
+		return 0, self.video[self.num_frames_read]
+
+	def release(self):
+		""" Empty our array. If we had a hold on the camera, we would give it back here. """
+		self.video = ()
+		self.num_frames_read = 0