This is a Capacitor plugin that lets you scan documents using Android and iOS. You can use it to create apps that let users scan notes, homework, business cards, receipts, or anything with a rectangular shape.
iOS | Android |
---|---|
npm install capacitor-document-scanner
npx cap sync
import { Capacitor } from '@capacitor/core'
import { DocumentScanner } from 'capacitor-document-scanner'
const scanDocument = async () => {
// start the document scanner
const { scannedImages } = await DocumentScanner.scanDocument()
// get back an array with scanned image file paths
if (scannedImages.length > 0) {
// set the img src, so we can view the first scanned image
const scannedImage = document.getElementById('scannedImage') as HTMLImageElement
scannedImage.src = Capacitor.convertFileSrc(scannedImages[0])
}
}
Here's what this example looks like with several items
You can limit the number of scans. For example if your app lets a user scan a business card you might want them to only capture the front and back. In this case you can set maxNumDocuments to 2. This only works on Android.
import { Capacitor } from '@capacitor/core'
import { DocumentScanner } from 'capacitor-document-scanner'
const scanDocument = async () => {
// limit the number of scans to 2
const { scannedImages } = await DocumentScanner.scanDocument({
maxNumDocuments: 2
})
// get back an array with scanned image file paths
if (scannedImages.length > 0) {
// set the img src, so we can view the first scanned image
const scannedImage = document.getElementById('scannedImage') as HTMLImageElement
scannedImage.src = Capacitor.convertFileSrc(scannedImages[0])
}
}
You can automatically accept the detected document corners, and prevent the user from making adjustments. Set letUserAdjustCrop to false to skip the crop screen. This limits the max number of scans to 1. This only works on Android.
import { Capacitor } from '@capacitor/core'
import { DocumentScanner } from 'capacitor-document-scanner'
const scanDocument = async () => {
// skip the crop screen
const { scannedImages } = await DocumentScanner.scanDocument({
letUserAdjustCrop: false
})
// get back an array with scanned image file paths
if (scannedImages.length > 0) {
// set the img src, so we can view the first scanned image
const scannedImage = document.getElementById('scannedImage') as HTMLImageElement
scannedImage.src = Capacitor.convertFileSrc(scannedImages[0])
}
}
iOS requires the following usage description be added and filled out for your app in Info.plist
:
-
NSCameraUsageDescription
(Privacy - Camera Usage Description
)
Read about Configuring Info.plist
in the iOS Guide for more information on setting iOS permissions in Xcode
scanDocument(options?: ScanDocumentOptions | undefined) => Promise<ScanDocumentResponse>
Opens the camera, and starts the document scan
Param | Type |
---|---|
options |
ScanDocumentOptions |
Returns: Promise<ScanDocumentResponse>
Prop | Type | Description |
---|---|---|
scannedImages |
string[] |
This is an array with either file paths or base64 images for the document scan. |
status |
ScanDocumentResponseStatus |
The status lets you know if the document scan completes successfully, or if the user cancels before completing the document scan. |
Prop | Type | Description | Default |
---|---|---|---|
croppedImageQuality |
number |
Android only: The quality of the cropped image from 0 - 100. 100 is the best quality. | : 100 |
letUserAdjustCrop |
boolean |
Android only: If true then once the user takes a photo, they get to preview the automatically detected document corners. They can then move the corners in case there needs to be an adjustment. If false then the user can't adjust the corners, and the user can only take 1 photo (maxNumDocuments can't be more than 1 in this case). | : true |
maxNumDocuments |
number |
Android only: The maximum number of photos an user can take (not counting photo retakes) | : 24 |
responseType |
ResponseType |
The response comes back in this format on success. It can be the document scan image file paths or base64 images. | : ResponseType.ImageFilePath |
scanMode |
'scanDocument' | 'takeFullPicture' |
Specify the mode of scanning. Only works in iOS. On Android it is ignored. |
Members | Value | Description |
---|---|---|
Success |
'success' |
The status comes back as success if the document scan completes successfully. |
Cancel |
'cancel' |
The status comes back as cancel if the user closes out of the camera before completing the document scan. |
Members | Value | Description |
---|---|---|
Base64 |
'base64' |
Use this response type if you want document scan returned as base64 images. |
ImageFilePath |
'imageFilePath' |
Use this response type if you want document scan returned as inmage file paths. |
Copyright 2022 David Marcus
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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