Save Frames To Video Opencv

OpenSceneGraph Forum implemented a component to save the recent frames in a video file in real time? The only solution I found was implemented using OpenCV. (frame, 180)) in my codes to save the videos? I've seen some. Topics taught in this course include summation notation, image similarity metrics, and video processing. docx), PDF File (. OpenCV comes with many powerful video editing functions. I want to save the output video into a file instead of displaying it and tried using cvcaptureimage but still unable to get the result #include int main(int argc, char *argv[]). For example, saving streaming video from a video camera in real time. I've installed the 1. This is a "Video for Windows" implementation not OpenCV, but because VfW breaks down starting the webcam, I'm using OpenCV to initiate the link. MPEG1/2, as well as H. We'll discuss how to: Access a video stream, using either a builtin/USB webcam or the Raspberry Pi camera module. OpenCV provides a very simple interface to this. pdf), Text File (. You must know that this code wont work on Mac OS X with OpenCV 2. Capture Video from Camera¶. Here is a real time video inferencing using opencv to capture video and slice through the frames. A shadow is detected if pixel is a darker version of the background. 264 are supported. Use uncompressed image format (eg. This frame loop plays like a video, and it is nice to see your results, but you don’t get the frame rate like a video. OpenCV uses old code on DirectShow, which is not supported well on new platform. so module is created and the RaspiCam_Cv class available. How can I access a video capture device. VideoCapture and OpenCV. In this step, we will learn how to diplay a video from the camera board, using OpenCV display (and not the native preview GPU window). According to Docs, alpha regulates the update speed (how fast the accumulator “forgets” about earlier images). On Windows, cvCreateVideoWriter() will display a dialog box for you to select the appropriate codec you want to use when saving the video. Video I/O - an easy-to-use interface to video capturing and video codecs. tien nguyen. AVI, audio can however be provided. To play the frames in the Jupyter Notebook with animation, I use IPython display, Image, and clear_output. Record video with Python 3 + OpenCV 3 on OSX This simple example will demonstrate how to use python + OpenCV 3 to capture frames from the webcam and save them as a video file of mp4 format on your Mac. Enable your configured aws account on rekognition and S3; Create a rekognition collection this will be the collection of faces the camera stream is matched against > #aws rekognition create-collection –collection-id “faces” –region us-east-1. Expand your OpenCV knowledge & use of machine learning to your advantage with this practical hand-on course! OpenCV 4 Computer Vision with Python Recipes [Video] JavaScript seems to be disabled in your browser. OpenCV also allows us to save that operated video for further usage. simple c++ functions to extract frames of a video file into a vector of Mat and saving the vector as jpg images using OpenCV 2. Apply Gaussian blur to distance mapping. I load my video, edit it, and try to save, it does not work. To learn how to use the OpenCV library, go to https://opencv. PyCuda out perform Numpy + openCV 4. Use uncompressed image format (eg. NET environment. If a movement is detected the program start recording the webcam in a video file fo 10 seconds. Take a look in the OpenCV website and tutorials for further information. 02/08/2017; 33 minutes to read +2; In this article. Hi everyone, I am new to OpenCV. At the end of this step, you should be able to capture frames from your camera board, and use them directly using OpenCV ! Enjoy, creativity will be your only limit (and perhaps CPU a little bit). We will see How to read video, display video and save video, How to capture from Camera and display it, we will see these functions : cv. pdf), Text File (. Computers have helped mankind solve lots of problems and complete lots of difficult tasks. OpenCV DNN example - File-Based and MIPI Camera OpenCV Inference The OpenCV offers a unitary solution for both neural network inference (DNN module) and classic machine learning algorithms (ML module). Roll Pitch Yaw. I am using opencv2. This filter is based on the value of the pixels on the image in grayscale to find faces. 2019 4:39 am Hi, I am trying to save cropped video. Capture and save webcam video in Python using OpenCV. Tutorial - How to Process Video Frames Using OpenCV - Duration: 16:19. su dung opencv trong sieu phan giai anh. I'm trying to save a video but I have really. Can anyone suggest how to do this with some pieces of code. OpenCV DNN example - File-Based and MIPI Camera OpenCV Inference The OpenCV offers a unitary solution for both neural network inference (DNN module) and classic machine learning algorithms (ML module). This article shows you how to use a MediaFrameReader with MediaCapture to get media frames from one or more available sources, including color, depth, and infrared cameras, audio devices, or even custom frame sources such as those that produce skeletal tracking frames. Reading a Video. Alex asks: I need to count the total number of frames in a video file with OpenCV. According to Docs, alpha regulates the update speed (how fast the accumulator “forgets” about earlier images). show the result of the acquisition on screen 10/18/2016 Introduction to OpenCV 41 42. OpenCV and Visual c++ Programming in image processing - Free download as Word Doc (. I get the video but the frames are order randomly, how can I arrange them in a sequential order? thanks for the post. opencv - not writing output with cv2. pip install opencv-python Face detection using Haar cascades is a machine learning based approach where a cascade function is trained with a set of input data. @param learningRate The value between 0 and 1 that indicates how fast the background model is learnt. JavaCV capture-save-flip-show live camera Java Code : Capture Image from webcam using JavaCV JavaCV- Image load, smooth and save OpenCV-JavaCV : eclipse project configuration wind CSS Format Source Code in blog articles - blogger, HTML/XML Tag Parsing using Regex in Java Android Reverse Engineering - decompile. Finally, let’s check out the images. Capturing videos using OpenCV is pretty simple as well. 2 seconds and using this frame, we make a. Its argument can be either the device index or the name of the video file to be read. VideoCapture(0) and start extracting frames. Published on April I coded the video to frame conversion part in python and is a quick way to input a video file and save the output frames as 'jpg' image. While working on a blog post where I was utilizing. opencv) submitted 4 years ago by CaptainDexterMorgan I'm working on a project written in Python that opens and analyzes AVI files and it works fine on my computer (Linux system). The purpose of this tutorial is to learn how to write frames to video using OpenCV and Python. Here I will show how to implement OpenCV functions and apply it in various aspects using some examples. Let's try to do something interesting using CV2. The only way I. mp4 file (using FileVideoWriter). Paste the following line: import cv2. pdf), Text File (. This will help developers who love the C# and OpenCV environment. video - OpenCV videowriter H264 codec (ffmpeg) I want to save a video with opencv with lossless compresion so I don't lose any details of the frames. OpenCV C# Wrapper Based Video Enhencement Using Different Optical Flow Methods in the Super Resolution - Free download as PDF File (. isColor – If it is not zero, the encoder will expect and encode color frames, otherwise it will work with grayscale frames (the flag is currently supported on Windows only). I have this code below which tries to take an AVI file, transforms it to grey scale frame by frame and creates a new AVI file. For an introduction to using SoftwareBitmap, see Create, edit, and save bitmap images. The purpose of software is to record video through camera, make frames of video & save them to a folder. Due to this OpenCV for video containers supports only the avi extension, its first version. All examples were written for OpenCV version 3. We are going to create frames from the video stored in our local machine & then store the frames in our local drive. We'll discuss how to: Access a video stream, using either a builtin/USB webcam or the Raspberry Pi camera module. Capture: Video Files Capture : Shows the use of the capture method to load videos save them from a web cam and look at individual frames. goodFeaturesToTrack(). Shift frames. Process media frames with MediaFrameReader. In OpenCV, a video can be read either by using the feed from a camera connected to a computer or by reading a video file. I'm trying to save a video but I have really. I would be grateful if you help me with it. The list of available codes can be found in fourcc. Splitting Video Into Images with OpenCV and Python How to Process Video Frames. By the way, I am on macOS High Sierra 10. If the OpenCV is found when compiling the library, the libraspicam_cv. Opencv tutorial simple code in C++ to capture video from File, Ip camera stream and also the web camera plug into the computer. In this case we use CV_BGR2GRAY (because of imread has BGR default channel order in case of color images). sometimes OpenCV will return. OpenCV is a vast library that helps in providing various functions for image and video operations. I want to access that camera through opencv. All examples were written for OpenCV version 3. We’ll be using our knowledge gained from last week’s blog post on writing video to file with OpenCV to implement this functionality. VideoCapture(). She also showed how to use regions of interest within the frame to determine the direction in which the Caltrain was traveling. If you choose to set up OpenCV on your own you have to set the following environment variables before installing opencv4nodejs: OPENCV_INCLUDE_DIR pointing to the directory with the subfolders opencv and opencv2 containing the header files; OPENCV_LIB_DIR pointing to the lib directory containing the OpenCV. Intel Media SDK can now be utilized by our videoio module to do hardware-accelerated video encoding/decoding. This article shows you how to use a MediaFrameReader with MediaCapture to get media frames from one or more available sources, including color, depth, and infrared cameras, audio devices, or even custom frame sources such as those that produce skeletal tracking frames. OpenSceneGraph Forum implemented a component to save the recent frames in a video file in real time? The only solution I found was implemented using OpenCV. Raspberry Pi Camera + Python + OpenCV (Day1) 5000 -o video. From my perspective one of the most intriguing applications of all this simple image and file handling so far is reading in data from a webcam. Your code works first time and your explanations of what it is doing are excellent – thank you very much. OpenCV is a library of functions that allow us to quickly perform computer vision tasks (e. Hi all, I am an absolute beginner wrt. xml face, and save it into the same directory as your Python* script. Record video with Python 3 + OpenCV 3 on OSX This simple example will demonstrate how to use python + OpenCV 3 to capture frames from the webcam and save them as a video file of mp4 format on your Mac. This format is very simple and not the most efficient, but has the advantage that all browsers support it natively and without any client-side scripting required. set video file name and save directory property in your setting. I also want to process every frame in stream then save processed frames as video file. For the radial factor one uses the following formula: So for an old pixel point at (x,y) coordinates in the input image, its position on the corrected output image will be (x_{corrected} y_{corrected}). SIVP can only read frames one by one using avireadframe. Then save the training matrix as the XML file specified by. Hi I am newbie to both OpenCV and Python. 7x more speed). From my computer, I will use the frames for Image Processing and Computer Vision us. Video can be captured from USB Cameras, IEEE 1394 (Firewire) Cameras, or Video Cards with composite or S-video input devices connected to the computer. pdf) or read online for free. Reading images sequentially without using videocap Convert an Image from one color space to another b RGB to GrayScale Conversion OpenCV code; Capturing a video form a file or webcam in opencv Reason for increase in the size of image as i save OpenCV-Image Loading and Saving it using imwrite. Objective Lightning Probability Forecast Tool Phase II. Example on python3. Gone are the days when all computers did was simple arithmetic operations, computers now drive the world. Webcam Video Access with OpenCV on Raspberry Pi. How can I access a video capture device. Open the camera instead of the file using cv2. Optimize performance of inference service on CPUs and save computing resources using the iQIYI deep learning cloud platform Optimization Practice of Deep Learning Inference Deployment on Intel® Processors | Intel® Software. If no frames has been grabbed (camera has been disconnected, or there are no more frames in video file), the methods return false and the functions return NULL pointer. I want to save the frames into a file. For the first argument, it should be given a video capturing structure. Do anyone know a gstreamer command to save webcam video in patches based on MB size. I searched a lot at web, but didn't find a good and whole solution, so I decided to program by myself. (2) Opencv 版本的查看 一般在安装 python 的时候,会安装一些 opencv 相关的依赖项,我们要想知道是否已经安装了 opencv 以及它的版本号,可以在终端下执行: pkg-config --modversion opencv 。. To save image sequence use a proper filename (eg. xml contains an openCV training matrix of GIST descriptors of images in the "negative" class (class 2). For this video, a zero value for the CurrentTime property indicates that no frames have been read from the video. OpenCV comes with many powerful video editing functions. Of course, you can also play with the parameters of the commands, for instance you can compute the average/median only for a subset of video frames (here, from frame 500 to frame 1499):. docx), PDF File (. Image arithmetics and Logic - OpenCV with Python for Image and Video Analysis 5 OpenCV with Python - Read and Write Images Building an image processing pipeline with Python - Duration:. Which will save our gray_image as Gray_Image. read method of cv2. Apply Gaussian blur to distance mapping. opencv, simple source code Video frames to jpeg files (VideoCapture, imwrite) - description. Re: capture images and then sequence them? Reply #1 - Jul 23 rd , 2009, 3:34am i'll make an example using opencv; you can do the same with any video lirary simply changing the opencv calls with you chosen library calls. edu/~tboult/CS330/NOTES/OpenCV_2005Q4_tutorial. In short, this is a Flask server that uses a streaming response to provide a stream of video frames captured from a camera in Motion JPEG format. Re: capture images and then sequence them? Reply #1 - Jul 23 rd , 2009, 3:34am i'll make an example using opencv; you can do the same with any video lirary simply changing the opencv calls with you chosen library calls. Net wrapper for OpenCV. If you want lossless video file you need to use a lossless codecs (eg. From my perspective one of the most intriguing applications of all this simple image and file handling so far is reading in data from a webcam. It works on Python3 with OpenCV 3+ import cv2 import time import os def video_to_frames(input_loc, output_loc): """Function to extract frames from input video file and save them as separate frames in an output directory. Adding Mustaches to Webcam Feed with OpenCV and Python a royalty-free video from Stock Footage for Free and detecting faces in the stream of webcam frames. This project requires a webcam to serve as Intel Galileo’s “eyes” to capture pictures and videos and apply algorithms using OpenCV. Capture: Video Files Capture : Shows the use of the capture method to load videos save them from a web cam and look at individual frames. First, you instantiate your cv2. Later I want to save only those frames as a single video. How can i read or write video without OpenCV? I have used the following Matlab code to extract frames of a video, however, in the folder in which the frames are stored I see that after every. MPEG1/2, as well as H. mp4" in the code with a valid location to a video in your computer. Real-Time Object Detection Using YOLO Model. opencv) submitted 4 years ago by CaptainDexterMorgan I'm working on a project written in Python that opens and analyzes AVI files and it works fine on my computer (Linux system). Like reversing the video file or crop the video etc. ("My cam video", frame. Computers have helped mankind solve lots of problems and complete lots of difficult tasks. Given a video in mp4 format, extract_jpg_frm_mp4 extracts frames from the video at a specified rate. It opens the camera, records the video, closes the window when you press ‘q’, and saves the video in. Here I will show how to implement OpenCV functions and apply it in various aspects using some examples. We’ll be using our knowledge gained from last week’s blog post on writing video to file with OpenCV to implement this functionality. The image format is chosen based on the filename extension, see imread for the list of extensions. Target acquired: Finding targets in drone and quadcopter video streams using Python and OpenCV. Video writer class. Create a new Python file named face_detect. save them into a list and iterate over them to get cropped/flipped/reversed video. BMP) to save raw frames. imgcodecs provides methods to read and write images. video - OpenCV videowriter H264 codec (ffmpeg) I want to save a video with opencv with lossless compresion so I don't lose any details of the frames. Finally, let’s check out the images. This is done to reduce the noise in the image and to separate out the outlines of the fingers for the later processing stages. Real-Time Object Detection Using YOLO Model. x functions cvRetrieveFrame and cv. Initialize values. In windows just use Opencv Installation by Nugets packages Here. Create a VideoReader object and display the value of the CurrentTime property. Opencv reading video files, reading video stream, Images, IP and Web cameras. Cross-Platform C++, Python and Java interfaces support Linux, MacOS, Windows, iOS, and Android. Let’s try to do something interesting using CV2. BMP) to save raw frames. an additional parameter that indicates what kind of transformation will be performed. Our observation items include (1) thunderstorm electrical fields and lightning-caused electric field changes at multi sites around the wind turbine, (2) electrical currents at the bottom of the wind turbine and its lightning protection tower, (3) normal video and high speed image of lightning optical channels. GitHub Gist: instantly share code, notes, and snippets. png' where # x is the frame index vidcap = cv2. A direct limitation of this is that you cannot save a video file larger than 2 GB. And then show all those faces on the live video. Bytedeco makes native libraries available to the Java platform by offering ready-to-use bindings generated with the codeveloped JavaCPP technology. I am trying to write a simple python script to read the mp3 and play it. Roll Pitch Yaw. Take a look in the OpenCV website and tutorials for further information. Check it out: The images are read one-by-one and hence videos are produced due to fast processing of frames which makes the individual images move. Calculating real world co-ordinates using stereo images in Python and OpenCV. Comparison of average/median frame from the video clip of P!nk - Try. In OpenCV, a video can be read either by using the feed from a camera connected to a computer or by reading a video file. Vision Acquisition Software is driver software for acquiring, displaying, logging, and monitoring images from a multitude of camera types. The purpose of software is to record video through camera, make frames of video & save them to a folder. What’s annoying is that even though OpenCV does things like face detection, it doesn’t come with a blob detection solution built in. BMP) to save raw frames. Search for jobs related to Opencv android video or hire on the world's largest freelancing marketplace with 15m+ jobs. And this is big problem, because i am need in it. OpenCV (Open Source Computer Vision Library) is an open source computer vision and machine learning software library. Utilizing OpenCV in C#. ("My cam video", frame. simple c++ functions to extract frames of a video file into a vector of Mat and saving the vector as jpg images using OpenCV 2. Then save the training matrix as the XML file specified by. If no frames has been grabbed (camera has been disconnected, or there are no more frames in video file), the methods return false and the functions return NULL pointer. 9 - extract_frames. xml contains an openCV training matrix of GIST descriptors of images in the "negative" class (class 2). For example, saving streaming video from a video camera in real time. OpenCV comes with many powerful video editing functions. Documentation, API, white papers, examples and more - all you need to start working with your depth camera from Intel RealSense. Bu I don't know how to get frames from VLC for process. mp4 file (using FileVideoWriter). Capture: Video Files Capture : Shows the use of the capture method to load videos save them from a web cam and look at individual frames. Video Analysis using OpenCV-Python. Using OpenCV to input a video file and to read each frame then save it to a image file with a Python script. We’ll be using our knowledge gained from last week’s blog post on writing video to file with OpenCV to implement this functionality. OpenCV C# Wrapper Based Video Enhencement Using Different Optical Flow Methods in the Super Resolution - Free download as PDF File (. In the case of video, consecutive frames were overlaid to determine the rate of change of the light escaping cloud top. Lucas-Kanade Optical Flow in OpenCV¶ OpenCV provides all these in a single function, cv2. mpg): ffmpeg -f lavfi -i testsrc. I need to send live video frames from my Raspberry Pi with a PiCamera (or USB Camera is fine too) to my Computer. It's used into Image Processing, Machine Learning and Computer Vision in the area of AI. But the thing is I want the opencv to take picture for the faces it captures. pdf) or read online for free. Let’s try to do something interesting using CV2. Everything works with the xvid codec but offcourse this is not a lossless compression so I found that the x264 codec is suitable. I get the video but the frames are order randomly, how can I arrange them in a sequential order? thanks for the post. This tutorial is a practice session of learning video processing using web camera in a laptop. Reading images sequentially without using videocap Convert an Image from one color space to another b RGB to GrayScale Conversion OpenCV code; Capturing a video form a file or webcam in opencv Reason for increase in the size of image as i save OpenCV-Image Loading and Saving it using imwrite. 2007-01-01. Capture Video from Camera¶. Import OpenCV and its dependencies. 1a version with VC++ 2008. Video I/O - an easy-to-use interface to video capturing and video codecs. Read frames from the stream. 4a on mac if that helps. Capturing Video: Check out the following image:. read method of cv2. Embedded into OpenCV Intel IPP subset has been upgraded from 2015. I'm trying to extract the first frame of a sample video file with OpenCV however it doesnt work: import cv2 f = cv2. Streaming encoded video using openCV. making a picture black and white, canny edge, face recognition, …). Alex asks: I need to count the total number of frames in a video file with OpenCV. opencv c++ - Free download as Text File (. It works on Python3 with OpenCV 3+ import cv2 import time import os def video_to_frames(input_loc, output_loc): """Function to extract frames from input video file and save them as separate frames in an output directory. Yes, but for now i found i way to save the frames, but now it overwrite the same file all the time, so that i don't have a list of frames but just one that change every second. Use uncompressed image format (eg. simple c++ functions to extract frames of a video file into a vector of Mat and saving the vector as jpg images using OpenCV 2. FFMPEG FFV1, Huffman HFYU, Lagarith LAGS, etc…). 4,006 we implemented a “Haarcascade Frontalface” filter from OpenCV. OpenCV C# Wrapper Based Video Enhencement Using Different Optical Flow Methods in the Super Resolution - Free download as PDF File (. Today's blog post is part of a two part series on working with video files using OpenCV and Python. The main reference I have used for this, is the OpenCV 2. Recommendation. OpenCV DNN example - File-Based and MIPI Camera OpenCV Inference The OpenCV offers a unitary solution for both neural network inference (DNN module) and classic machine learning algorithms (ML module). VideoWriter(filename, codec selection, frames per second, (width, height)). This presentation describes the improvement of a set of lightning probability forecast equations that are used by the 45th Weather Squadron forecasters for their daily 1100 UTC (0700 EDT) weather briefing during the warm season months of May-September. This will help developers who love the C# and OpenCV environment. Record video with Python 3 + OpenCV 3 on OSX This simple example will demonstrate how to use python + OpenCV 3 to capture frames from the webcam and save them as a video file of mp4 format on your Mac. As said before the program analyse the images taken from the webcam and intent to detect movement. Start video loop. … some other helper modules, such as FLANN and Google test wrappers, Python bindings, and others. The video, available below, has got great success and has been viewed more than 5000… Continue reading. calcOpticalFlowPyrLK(). Now we can save the frames as a video file. OpenCV Charuco Camera-Calibration Posted on October 29, 2017 by peter OpenCV is an amazing tool that can provide accurate pose information in real-time, but first you have to provide it with a model of your camera. x functions cvRetrieveFrame and cv. acquire the video stream from the webcam 2. mp4 file (using FileVideoWriter). It also demostrates the use of the VideoWriter class. As said before the program analyse the images taken from the webcam and intent to detect movement. Then you start a loop, calling the. How can I access a video capture device. In this step, we will learn how to diplay a video from the camera board, using OpenCV display (and not the native preview GPU window). simple c++ functions to extract frames of a video file into a vector of Mat and saving the vector as jpg images using OpenCV 2. Linux Kernel PWM Driver with SYSFS. Published on April I coded the video to frame conversion part in python and is a quick way to input a video file and save the output frames as 'jpg' image. Please note that you have to replace "D:/My OpenCV Website/A Herd of Deer Running. Convert Image Frames to Video File using OpenCV in Python → 7 thoughts on “ Extract Each Frame from a Video File using OpenCV in Python ” Not needed 21 April, 2018 at 1:01 am. 0 (compiled with opencv sources and Jetson Nano) make me think that PyCuda is 10 to 15 time faster than opencv 3. One year ago I wrote the simular article, but I used Media Foundation framework - Capturing video from web-camera on Windows 7 and 8 using Media Foundation. OpenCv and Microsoft Visual C++ : Installation and configuration, Microsoft visual studio,Image Processing. For an introduction to using SoftwareBitmap, see Create, edit, and save bitmap images. h264 錄 5 秒的 1080p30 影片 , 長 640x 寬 480 $ raspivid -t 5000 -w 640 -h 480 -o video. Most common persisting method is to save the image or the video to a file. Steps: Read each image using cv2. OpenCV has a VideoWriter class for just this purpose. Using OpenCV to input a video file and to read each frame then save it to a image file with a Python script. Using OpenCV takes a mp4 video and produces a number of images. I am using opencv2. Create a VideoReader object for the example movie file xylophone. For saving images, we use cv2. I searched a lot at web, but didn't find a good and whole solution, so I decided to program by myself. 1) Case of no rotation, only translation parallel to the horizontal axis of the image plane, cameras with equal focal lengths. Motion JPEG 2000 (and common video formats) that permits the carriage of audio, the older (and incompatible with) Motion JPEG doesn't code any audio, as it's simply a concatenation of still JPEG frames. GitHub Gist: instantly share code, notes, and snippets. BMP) to save raw frames. This tutorial is a practice session of learning video processing using web camera in a laptop. It's used into Image Processing, Machine Learning and Computer Vision in the area of AI. The high resolution image has sizes of around 350KB, while the low resolution image has sizes around 80KB. opencv c++ - Free download as Text File (. I am trying to write a simple python script to read the mp3 and play it. VideoWriter(). imwrite() which saves the image to a. I got the 2 folders (opencv_simulator, opencv_device) from Yoshimasa Niwa (THANKS!!!!!) and placed them in my XCode project directory. This problem is reported in some other systems too. making a picture black and white, canny edge, face recognition, …). In this article, I install the Raspberry Pi Camera which I will be using to add camera vision to a robot. docx), PDF File (. Hi all, I am an absolute beginner wrt. We are going to create frames from the video stored in our local machine & then store the frames in our local drive. OpenCV Camera Calibration and 3D Reconstruction Formulas. My problem is, as i believe, on the linking of the library (step 6). The technique reported in [8] makes use of visual 3-D SLAM for localization. Reading a Video. How to Use Background Subtraction Methods. To get the video feed we initialize a while loop. Then save the training matrix as the XML file specified by. Calculate Object Distance From Camera Opencv Android. Using OpenCV to input a video file and to read each frame then save it to a image file with a Python script. ("My cam video", frame.