webcam-capture

问题 This question is very similar to V4L2 absolute exposure setting has (almost) not effect I have a UVC compliant camera that I am running on a Raspberry Pi CM3+ module. It appears as video0 . Using the tools/drivers v4l2-ctl , qv4l2 or guvcview the absolute exposure cannot be controlled, yet it can be controlled when using Amcap on Windows 10. The camera has two exposure modes manual and aperature controlled . When in aperature controlled the exposure levels in the image change dynamically,

问题 Given the following PyQt code, I can perfectly capture the webcam's streaming video. Now, I want to modify code, so a button named ''capture'' button is added that once pressed captures the streaming video and saves the image . How can I do this? The obtained small image will be used to query an object recognition server. import sys from PyQt4 import QtGui, QtCore import cv2 class QtCapture(QtGui.QWidget): def __init__(self, *args): super(QtGui.QWidget, self).__init__() self.fps = 24 self.cap

问题 (function ($) { var webcam = { "extern": null, // external select token to support jQuery dialogs "append": true, // append object instead of overwriting "width": 320, "height": 240, "mode": "callback", // callback | save | stream "swffile": "../Webcam_Plugin/jscam_canvas_only.swf", "quality": 85, "debug": function () {}, "onCapture": function () {}, "onTick": function () {}, "onSave": function () {}, "onLoad": function () {} }; window["webcam"] = webcam; $["fn"]["webcam"] = function(options)

问题 I am using OpenCV4 along with python 3 to open a webcam, grab the frames and display them in a window, just like the first code tutorial provided here. However, it takes a different amount of time grabbing different frames: sometimes it takes 0.01 s to grab, and sometimes it takes 0.33 s, which creates lags when showing the frames in the window. Is there a way to force a constant time when grabbing frames so that i can see the video without lag? I think it is happening with OpenCV because

问题 I am trying to use WebcamJS in Chrome on Windows tablet which has 2 webcams. However, it is working only with back webcam. Any idea how to make it work with front webcam ? Thanks for any hints. 回答1: There's a fork of that project that allows that very feature (the ability to choose the camera device): https://github.com/carvilsi/webcamjs Hope this helps. 来源： https://stackoverflow.com/questions/28485544/how-to-use-front-tablets-webcam-with-html-getusermedia

问题 Here is the gist of what I am trying to achieve: Capture a webcam image from the Edit view. (working) Assign the image a file name and path. (working) Save the image to the images folder. (working) Store the path to the image in the database. (Not working) Here is my Capture controller: public void Capture(String FileLocation) { //var FileLocation = Server.MapPath("~/Images/test.jpg"); var stream = Request.InputStream; string dump; using (var reader = new StreamReader(stream)) dump = reader

问题 When accessing webcam through python opencv, isOpened() returns False and no data is read. Does it has to do something with wsl? 回答1: According to this github issue, hardware access is not supported yet in WSL: Ben Hillis: Hardware access is another area we will be investigating in the future. All hardware related CLI tools seem to fail (dmesg, lsblk, lsusb returns nothing, /dev is empty...) so it looks like this statement is still valid today. That explains why you cannot access your camera

问题 we are using a Raspberry Pi + Python 3.4 + PyGame to capture an image from a specific USB webcam. We use this simple code to capture (it works ok): pygame.camera.init() cam = pygame.camera.Camera(pygame.camera.list_cameras()[0],(1280,720)) cam.start() time.sleep(1) webcamImage = cam.get_image() The problem comes here: we have to convert this webcamImage into a PIL image. We follow this link but unfortunately the function Image.fromstring() not exists anymore. So, we can't do that : pil_string

问题 I've written a headless UWP Background Application and deployed it to a Raspberry PI running Windows 10 IoT. The Pi has an old Logitech webcam plugged into one of the USB ports and I'd like to be able to capture still images from it. I've lifted code from a Microsoft Blog on the subject (albeit aimed at UWP on the Xbox), but my app seems unable to detect any cameras at all. The following call comes back with no results: var allVideoDevices = await DeviceInformation.FindAllAsync(DeviceClass

问题 I'm using Webcam Capture API in java to access my webcam. Webcam Capture API is built on Swing, I know that, however I want to combine the Webcam Swing class with my JavaFX class. The JavaFX class displays a rectangle on the screen. My goal is: I run my JavaFX class which displays the rectangle on the screen. At some point (e.g. mouse click) I want to start the Webcam. The Webcam is setup to look at the screen and should then do certain things with the images of the rectangle. JavaFX class: