From 0dec7130daf3fef00fb69a8df7f1c4fb7e82f913 Mon Sep 17 00:00:00 2001
From: yumoqing <yumoqing@gmail.com>
Date: Wed, 23 Sep 2020 12:16:27 +0800
Subject: [PATCH] bugfix

---
 kivyblocks/kivycamera.py | 53 ++++++++++++++++++++++++++++++++++------
 1 file changed, 46 insertions(+), 7 deletions(-)

diff --git a/kivyblocks/kivycamera.py b/kivyblocks/kivycamera.py
index 88691be..484d384 100644
--- a/kivyblocks/kivycamera.py
+++ b/kivyblocks/kivycamera.py
@@ -5,28 +5,61 @@ from kivy.graphics.texture import Texture
 from kivy.factory import Factory
 import cv2
 
+def set_res(cap, x,y):
+    cap.set(cv2.CAP_PROP_FRAME_WIDTH, int(x))
+    cap.set(cv2.CAP_PROP_FRAME_HEIGHT, int(y))
+    return cap.get(cv2.CAP_PROP_FRAME_WIDTH),cap.get(cv2.CAP_PROP_FRAME_HEIGHT)
+
 class KivyCamera(Image):
-	def __init__(self, fps=25.0, face_detect=Falsem **kwargs):
+	def __init__(self, camera_id=0, fps=25.0, face_detect=False, **kwargs):
+		print('KivyCamera inited')
+		self.update_task = None
+		self.capture = None
 		super(KivyCamera, self).__init__(**kwargs)
-		self.capture = cv2.VideoCapture(0)
+		self.capture = cv2.VideoCapture(camera_id)
 		self.face_detect = face_detect
+		self.camera_id = camera_id
 		self.faceCascade = None
 		if face_detect:
-			self.faceCascade = cv2.CascadeClassifier("Resources/haarcascades/haarcascade_frontalface_default.xml")  # added
-		Clock.schedule_interval(self.update, 1.0 / fps)
+			# self.faceCascade = cv2.CascadeClassifier("Resources/haarcascades/haarcascade_frontalface_default.xml")  # added
+			self.faceCascade = cv2.CascadeClassifier('data/haarcascade/haarcascade_frontalface_default.xml')
+		self.update_task = Clock.schedule_interval(self.update, 1.0 / fps)
+
+	def on_size(self,o,size):
+		if self.capture:
+			self.capture.release()
+		self.capture = cv2.VideoCapture(self.camera_id)
+		size = set_res(self.capture,self.width,self.height)
+		print(size)
 
 	def add_face_detech(self,frame):
 		frameGray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
-		faces = self.faceCascade.detectMultiScale(frameGray, 1.1, 4)
+		faces = self.faceCascade.detectMultiScale(frameGray, 
+							scaleFactor = 1.2, minNeighbors = 5)
+		# THIS LINE RAISE ERROR 
+		# faces = self.faceCascade.detectMultiScale(frameGray, 1.1, 4)
+ 		# cv2.error: OpenCV(4.2.0) C:\projects\opencv-python\opencv\modules\objdetect\src\cascadedetect.cpp:1689: error: (-215:Assertion failed) !empty() in function 'cv::CascadeClassifier::detectMultiScale'
 		for (x, y, w, h) in faces:  # added
 			cv2.rectangle(frame, (x, y), (x + w, y + h), (255, 0, 0), 2)
+		return frame
 
 
 	def update(self, dt):
 		ret, frame = self.capture.read()
 		if ret:
+			if self.width / self.height > frame.shape[1] / frame.shape[0]:
+				fx = fy = self.height / frame.shape[0]
+			else:
+				fx = fy = self.width / frame.shape[1] 
+			
+			frame = cv2.resize(frame, None, 
+					fx=fx, fy=fy, 
+					interpolation=cv2.INTER_LINEAR)
 			if self.faceCascade:
-				frame = self.add_face_detech(frame)
+				try:
+					frame = self.add_face_detech(frame)
+				except:
+					pass
 			# convert it to texture
 			buf1 = cv2.flip(frame, 0)
 			buf = buf1.tostring()
@@ -36,4 +69,10 @@ class KivyCamera(Image):
 			# display image from the texture
 			self.texture = image_texture
 
-Factory.register('Camera',KivyCamera)
+	def __del__(self):
+		if self.update_task:
+			self.update_task.cancel()
+			self.update_task = None
+		self.cupture.close()
+
+Factory.register('KivyCamera',KivyCamera)