From 11319709e1e63de09b892a99d343e0895264abdd Mon Sep 17 00:00:00 2001
From: PySimpleGUI <PySimpleGUI@PySimpleGUI.com>
Date: Wed, 1 Jun 2022 15:44:19 -0400
Subject: [PATCH] Update to the latest coding guidelines.  Use PPM encoding as
 it's been shown to be more efficient

---
 DemoPrograms/Demo_OpenCV.py | 46 +++++++++++++++++++------------------
 1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/DemoPrograms/Demo_OpenCV.py b/DemoPrograms/Demo_OpenCV.py
index ea5cf72d..3abb443c 100644
--- a/DemoPrograms/Demo_OpenCV.py
+++ b/DemoPrograms/Demo_OpenCV.py
@@ -1,16 +1,18 @@
 #!/usr/bin/env python
 import PySimpleGUI as sg
-from PIL import Image
 import cv2 as cv
-import io
+# from PIL import Image
+# import io
 
 """
-Demo program to open and play a file using OpenCV
-It's main purpose is to show you:
-1. How to get a frame at a time from a video file using OpenCV
-2. How to display an image in a PySimpleGUI Window
-
-For added fun, you can reposition the video using the slider.
+    Demo program to open and play a file using OpenCV
+    It's main purpose is to show you:
+    1. How to get a frame at a time from a video file using OpenCV
+    2. How to display an image in a PySimpleGUI Window
+    
+    For added fun, you can reposition the video using the slider.
+    
+    Copyright 2022 PySimpleGUI
 """
 
 
@@ -28,37 +30,39 @@ def main():
 
     # ---===--- define the window layout --- #
     layout = [[sg.Text('OpenCV Demo', size=(15, 1), font='Helvetica 20')],
-              [sg.Image(filename='', key='-image-')],
-              [sg.Slider(range=(0, num_frames),
-                        size=(60, 10), orientation='h', key='-slider-')],
-              [sg.Button('Exit', size=(7, 1), pad=((600, 0), 3), font='Helvetica 14')]]
+              [sg.Image(key='-IMAGE-')],
+              [sg.Slider(range=(0, num_frames), size=(60, 10), orientation='h', key='-SLIDER-')],
+              [sg.Push(), sg.Button('Exit', font='Helvetica 14')]]
 
     # create the window and show it without the plot
     window = sg.Window('Demo Application - OpenCV Integration', layout, no_titlebar=False, location=(0, 0))
 
     # locate the elements we'll be updating. Does the search only 1 time
-    image_elem = window['-image-']
-    slider_elem = window['-slider-']
-
+    image_elem = window['-IMAGE-']
+    slider_elem = window['-SLIDER-']
+    timeout = 1000//fps                 # time in ms to use for window reads
+    
     # ---===--- LOOP through video file by frame --- #
     cur_frame = 0
     while vidFile.isOpened():
-        event, values = window.read(timeout=0)
+        event, values = window.read(timeout=timeout)
         if event in ('Exit', None):
             break
         ret, frame = vidFile.read()
         if not ret:  # if out of data stop looping
             break
         # if someone moved the slider manually, the jump to that frame
-        if int(values['-slider-']) != cur_frame-1:
-            cur_frame = int(values['-slider-'])
+        if int(values['-SLIDER-']) != cur_frame-1:
+            cur_frame = int(values['-SLIDER-'])
             vidFile.set(cv.CAP_PROP_POS_FRAMES, cur_frame)
         slider_elem.update(cur_frame)
         cur_frame += 1
 
-        imgbytes = cv.imencode('.png', frame)[1].tobytes()  # ditto
+        imgbytes = cv.imencode('.ppm', frame)[1].tobytes()  # can also use png.  ppm found to be more efficient
         image_elem.update(data=imgbytes)
 
+main()
+
             #############
             #    | |    #
             #    | |    #
@@ -74,6 +78,4 @@ def main():
         img.save(bio, format= 'PNG')    # save image as png to it
         imgbytes = bio.getvalue()       # this can be used by OpenCV hopefully
         image_elem.update(data=imgbytes)
-"""
-
-main()
+"""
\ No newline at end of file