npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

v4l2camera-pr48

v1.2.1

Published

Copy of v4l2camera with node v12+ support until pr #48 is merged - Capturing images from USB(UVC) webcam on linux machines

Downloads

23

Readme

> Copy of v4l2camera that fixes compile errors on nodejs 12+ - see pull request #48 <

orignal PR by @sebakerckhof - https://github.com/sebakerckhof

node-v4l2camera

Capturing images from USB(UVC) webcam on linux machines.

Requirements

  • node >= 10.x
  • video4linux2 headers
  • c and c++ compiler with -std=c11 and -std=c++14
    • gcc >= 4.9

Install

On linux machines:

npm install v4l2camera-pr48
  • package details: https://npmjs.org/package/v4l2camera

Usage

var v4l2camera = require("4l2camera-pr48");

var cam = new v4l2camera.Camera("/dev/video0");
if (cam.configGet().formatName !== "MJPG") {
  console.log("NOTICE: MJPG camera required");
  process.exit(1);
}
cam.start();
cam.capture(function (success) {
  var frame = cam.frameRaw();
  require("fs").createWriteStream("result.jpg").end(Buffer(frame));
  cam.stop();
});

For more detail see: examples/*.js (required "pngjs" modules)

API

Initializing and Configuration API

  • var cam = new v4l2camera.Camera(device)
    • device: e.g. "/dev/video0"
  • cam.formats: Array of available frame formats
  • var format = cam.formats[n]
    • format.formatName: Name of pixel format. e.g. "YUYV", "MJPG"
    • format.format: ID number of pixel format
    • format.width: Frame width
    • format.height: Frame height
    • format.interval.numerator and format.interval.denominator : Capturing interval per numerator/denominator seconds (e.g. 30fps is 1/30)
  • cam.configSet(format) : Set capture width, height, interval per numerator/denominator sec if the members exist in the format object
  • cam.configGet() : Get a format object of current config

Capturing API (control flow)

  • cam.start()
  • cam.stop(afterStoped)
    • call re-config(format) or re-start() in afterStoped() callback
  • cam.capture(afterCaptured): Do cache a current captured frame
    • use cam.frameRaw() in afterCaptured(true) callback

Capturing API (frame access)

  • cam.frameRaw(): Get the cached raw frame as Uint8Array (YUYU frame is array of YUYV..., MJPG frame is single JPEG compressed data)
  • cam.toYUYV(): Get the cached frame as Uint8Array of pixels YUYVYUYV... (will be deprecated method)
  • cam.toRGB(): Get the cached frame as Uint8Array of pixels RGBRGB... (will be deprecated method)

Capturing API (camera frame info)

  • cam.device: the device file name e.g. "/dev/video0"
  • cam.width: pixel width of the camera
  • cam.height: pixel height of the camera

Control API

  • cam.controls: Array of the control information
  • cam.controlGet(id): Get int value of the control of the id (id is one of cam.controls[n].id)
  • cam.controlSet(id, value): Set int value of the control of the id
  • var control = cam.controls[n]: Control spec
    • control.id: Control id for controlGet and controlSet
    • control.name: Control name string
    • control.type: "int", "bool", "button", "menu" or other types
    • control.max, control.min, control.step: value should be min <= v and v <= max and (v - min) % step === 0
    • control.default: default value of the control
    • control.flags: Several bool flags of the controls
    • control.menu: Array of items. A control value is the index of the menu item when type is "menu".

Build for Development

On linux machines:

cd myproject
mkdir -p node_modules
cd node_modules
git clone https://github.com/bellbind/node-v4l2camera.git v4l2camera
cd v4l2camera
npm install
cd ../..

"build/Release/v4l2camera.node" is exist after the build.

Tested Environments

  • Ubuntu wily armhf on BeagleBone Black with USB Buffalo BSW13K10H
  • Ubuntu wily amd64 on Acer Aspire One with its screen facecam
  • Travis-CI (build only): Build Status

Licenses

MIT and LGPL-3.0 dual