@yoonit/nativescript-camera

NativeScript Yoonit Camera

A NativeScript plugin to provide:

• Modern Android Camera API Camera X
• Camera preview (Front & Back)
• PyTorch integration (Android)
• Computer vision pipeline
• Face detection, capture and image crop
• Understanding of the human face
• Frame capture
• Capture timed images
• QR Code scanning

Table Of Contents

• Installation
• Usage
  • VueJS Plugin
  • Vue Component
• API
  • Props
  • Methods
  • Events
  • Messages
• Contribute

Installation

npm i -s @yoonit/nativescript-camera  

Usage

All the functionalities that the @yoonit/nativescript-camera provides is accessed through the YoonitCamera component, that includes the camera preview. Below we have the basic usage code, for more details, your can see the Methods, Events or the Demo Vue.

VueJS Plugin

main.js

import Vue from 'nativescript-vue'  
import YoonitCamera from '@yoonit/nativescript-camera/vue'  
  
Vue.use(YoonitCamera)  

After that, you can access the camera object in your entire project using this.$yoo.camera

Vue Component

App.vue

<template>
  <Page @loaded="onLoaded">
    <YoonitCamera
      ref="yooCamera"
      lens="front"
      captureType="face"
      imageCapture=true
      imageCaptureAmount=10
      imageCaptureInterval=500
      detectionBox=true
      @faceDetected="doFaceDetected"
      @imageCaptured="doImageCaptured"
      @endCapture="doEndCapture"
      @qrCodeContent="doQRCodeContent"
      @status="doStatus"
      @permissionDenied="doPermissionDenied"
    />
  </Page>
</template>

<script>
  export default {
    data: () => ({}),

    methods: {
      async onLoaded() {

        console.log('[YooCamera] Getting Camera view')
        this.$yoo.camera.registerElement(this.$refs.yooCamera)

        console.log('[YooCamera] Getting permission')
        if (await this.$yoo.camera.requestPermission()) {
          
          console.log('[YooCamera] Permission granted, start preview')
          this.$yoo.camera.preview()
        }
      },

      doFaceDetected({ 
        x, 
        y, 
        width, 
        height,
        leftEyeOpenProbability,
        rightEyeOpenProbability,
        smilingProbability,
        headEulerAngleX,
        headEulerAngleY,
        headEulerAngleZ
      }) {
        console.log(
          '[YooCamera] doFaceDetected',
          `
          x: ${x}
          y: ${y}
          width: ${width}
          height: ${height}
          leftEyeOpenProbability: ${leftEyeOpenProbability}
          rightEyeOpenProbability: ${rightEyeOpenProbability}
          smilingProbability: ${smilingProbability}
          headEulerAngleX: ${headEulerAngleX}
          headEulerAngleY: ${headEulerAngleY}
          headEulerAngleZ: ${headEulerAngleZ}
          `
        )
        if (!x || !y || !width || !height) {
          this.imagePath = null
        }
      },

      doImageCaptured({
        type,
        count,
        total,
        image: {
          path,
          source
        },
        inferences
      }) {
        if (total === 0) {
          console.log('[YooCamera] doImageCreated', `${type}: [${count}] ${path}`)
          this.imageCreated = `${count}`
        } else {
          console.log('[YooCamera] doImageCreated', `${type}: [${count}] of [${total}] - ${path}`)
          this.imageCreated = `${count} de ${total}`
        }
        console.log('[YooCamera] Mask Pytorch', inferences)
        this.imagePath = source
      },

      doEndCapture() {
        console.log('[YooCamera] doEndCapture')
      },

      doQRCodeContent({ content }) {
        console.log('[YooCamera] doQRCodeContent', content)
      },

      doStatus({ status }) {
        console.log('[YooCamera] doStatus', status)
      },

      doPermissionDenied() {
        console.log('[YooCamera] doPermissionDenied')
      }
    }
  }
</script>

API

Props

Props	Input/Format	Default value	Description
lens	"front" or "back"	"front"	The camera lens to use "front" or "back".
captureType	"none", "front", "frame" or "qrcode"	"none"	The capture type of the camera.
imageCapture	boolean	false	Enable/disabled save image capture.
imageCaptureAmount	number	0	The image capture amount goal.
imageCaptureInterval	number	1000	The image capture time interval in milliseconds.
imageCaptureWidth	"NNpx"	"200px"	The image capture width in pixels.
imageCaptureHeight	"NNpx"	"200px"	The image capture height in pixels.
colorEncoding	"RGB" or "YUV"	"RGB"	Only for android. The image capture color encoding type: "RGB" or "YUV".
detectionBox	boolean	false	Show/hide the face detection box.
detectionBoxColor	string	#ffffff	Set detection box color.
detectionMinSize	"NN%"	"0%"	The face minimum size percentage to capture.
detectionMaxSize	"NN%"	"100%"	The face maximum size percentage to capture.
roi	boolean	false	Enable/disable the region of interest capture.
roiTopOffset	"NN%"	"0%"	Distance in percentage of the top face bounding box with the top of the camera preview.
roiRightOffset	"NN%"	"0%"	Distance in percentage of the right face bounding box with the right of the camera preview.
roiBottomOffset	"NN%"	"0%"	Distance in percentage of the bottom face bounding box with the bottom of the camera preview.
roiLeftOffset	"NN%"	"0%"	Distance in percentage of the left face bounding box with the left of the camera preview.
roiAreaOffset	boolean	false	Enable/disable display of the region of interest area offset.
roiAreaOffsetColor	string	'#ffffff73'	Set display of the region of interest area offset color.
faceContours (Android Only)	boolean	false	Enable/disable display list of points on a detected face.
faceContoursColor (Android Only)	string	'#FFFFFF'	Set face contours color.
computerVision (Android Only)	boolean	false	Enable/disable computer vision model.
torch	boolean	false	Enable/disable device torch. Available only to camera lens "back".

Methods

Function	Parameters	Valid values	Return Type	Description
requestPermission	-	-	promise	Ask the user to give the permission to access camera.
hasPermission	-	-	boolean	Return if application has camera permission.
preview	-	-	void	Start camera preview if has permission.
startCapture	type: string	"none" "face" "qrcode" "frame"	void	Set capture type "none", "face", "qrcode" or "frame". Default value is "none".
stopCapture	-	-	void	Stop any type of capture.
destroy	-	-	void	Destroy preview.
toggleLens	-	-	void	Toggle camera lens facing "front"/"back".
setCameraLens	lens: string	"front" or "back"	void	Set camera to use "front" or "back" lens. Default value is "front".
getLens	-	-	string	Return "front" or "back".
setImageCapture	enable: boolean	true or false	void	Enable/disabled save image capture. Default value is false.
setImageCaptureAmount	amount: Int	Any positive Int value	void	For value 0, save infinity images. When the capture image amount is reached, the event onEndCapture is triggered. Default value is 0.
setImageCaptureInterval	interval: number	Any positive number that represent time in milliseconds	void	Set the image capture time interval in milliseconds.
setImageCaptureWidth	width: string	Value format must be in NNpx	void	Set the image capture width in pixels.
setImageCaptureHeight	height: string	Value format must be in NNpx	void	Set the image capture height in pixels.
setImageCaptureColorEncoding	colorEncoding: string	"YUV" or "RGB"	void	Only for android. Set the image capture color encoding type: "RGB" or "YUV".
setDetectionBox	enable: boolean	true or false	void	Set to show/hide the face detection box.
setDetectionBoxColor	color: string	hexadecimal	void	Set detection box color.
setFacePaddingPercent	percentage: string	Value format must be in NN%	void	Set face image capture and detection box padding in percentage.
setDetectionMinSize	percentage: string	Value format must be in NN%	void	Set the face minimum size percentage to capture.
setDetectionMaxSize	percentage: string	Value format must be in NN%	void	Set the face maximum size percentage to capture.
setROI	enable: boolean	true or false	void	Enable/disable face region of interest capture.
setROITopOffset	percentage: string	Value format must be in NN%	void	Distance in percentage of the top face bounding box with the top of the camera preview.
setROIRightOffset	percentage: string	Value format must be in NN%	void	Distance in percentage of the right face bounding box with the right of the camera preview.
setROIBottomOffset	percentage: string	Value format must be in NN%	void	Distance in percentage of the bottom face bounding box with the bottom of the camera preview.
setROILeftOffset	percentage: string	Value format must be in NN%	void	Distance in percentage of the left face bounding box with the left of the camera preview.
setROIMinSize	percentage: string	Value format must be in NN%	void	Set the minimum face size related within the ROI.
setROIAreaOffset	enable: boolean	true or false	void	Enable/disable display of the region of interest area offset.
setROIAreaOffsetColor	color: string	Hexadecimal color	void	Set display of the region of interest area offset color.
setFaceContours (Android Only)	enable: boolean	true or false	void	Enable/disable display list of points on a detected face.
setFaceContoursColor (Android Only)	color: string	Hexadecimal color	void	Set face contours color.
setComputerVision (Android Only)	enable: boolean	true or false	void	Enable/disable computer vision model.
setComputerVisionLoadModels (Android Only)	modelPaths: Array<string>	Valid system path file to a PyTorch computer vision model	void	Set model to be used when image is captured. To se more about it, Click Here.
computerVisionClearModels (Android Only)	-	-	void	Clear models that was previous added using setComputerVisionLoadModels.
setTorch	enable: boolean	true or false	void	Enable/disable device torch. Available only to camera lens "back".

Events

Event	Parameters	Description
imageCaptured	{ type: string, count: number, total: number, image: object = { path: string, source: any, binary: any }, inferences: [{ ['model name']: model output }] }	Must have started capture type of face/frame. Emitted when the face image file saved: type: "face" or "frame" total: total to create image.path: the face/frame image path image.source: the blob file image.binary: the blob file inferences: An Array with models output
faceDetected	{ x: number, y: number, width: number, height: number, leftEyeOpenProbability: number, rightEyeOpenProbability: number, smilingProbability: number, headEulerAngleX: number, headEulerAngleY: number, headEulerAngleZ: number }	Must have started capture type of face. Emit the face analysis, all parameters null if no more face detecting.
endCapture	-	Must have started capture type of face/frame. Emitted when the number of image files created is equal of the number of images set (see the method setImageCaptureAmount).
qrCodeContent	{ content: string }	Must have started capture type of qrcode (see startCapture). Emitted when the camera read a QR Code.
status	{ type: 'error'/'message', status: string }	Emit message error from native. Used more often for debug purpose.
permissionDenied	-	Emit when try to preview but there is not camera permission.

Face Analysis

The face analysis is the response send by the onFaceDetected. Here we specify all the parameters.

Attribute	Type	Description
x	number	The x position of the face in the screen.
y	number	The y position of the face in the screen.
width	number	The width position of the face in the screen.
height	number	The height position of the face in the screen.
leftEyeOpenProbability	number	The left eye open probability.
rightEyeOpenProbability	number	The right eye open probability.
smilingProbability	number	The smiling probability.
headEulerAngleX	number	The angle in degrees that indicate the vertical head direction. See Head Movements
headEulerAngleY	number	The angle in degrees that indicate the horizontal head direction. See Head Movements
headEulerAngleZ	number	The angle in degrees that indicate the tilt head direction. See Head Movements

Head Movements

Here we're explaining the above gif and how reached the "results". Each "movement" (vertical, horizontal and tilt) is a state, based in the angle in degrees that indicate head direction;

Head Direction	Attribute	v < -36°	-36° < v < -12°	-12° < v < 12°	12° < v < 36°	36° < v
Vertical	headEulerAngleX	Super Down	Down	Frontal	Up	Super Up
Horizontal	headEulerAngleY	Super Left	Left	Frontal	Right	Super Right
Tilt	headEulerAngleZ	Super Right	Right	Frontal	Left	Super Left

Messages

Pre-define message constants used by the status event.

Message	Description
INVALID_MINIMUM_SIZE	Face/QRCode width percentage in relation of the screen width is less than the set.
INVALID_MAXIMUM_SIZE	Face/QRCode width percentage in relation of the screen width is more than the set.
INVALID_OUT_OF_ROI	Face bounding box is out of the set region of interest.

Contribute and make it better

Clone the repo, change what you want and send PR.

For commit messages we use Conventional Commits.

Contributions are always welcome, some people that already contributed!

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Code with ❤ by the Cyberlabs AI Front-End Team