Document Scan

The Docutain Document Scanner SDK for Flutter comes with integrated, ready to use UI components for the document scan process. Colors can be changed to match your branding.

It is also possible to use the Document Scanner on imported images.

ScanEditPreview

Initialization

Follow the Getting started guide
Initialize the Docutain Flutter Scanner SDK as described here

Scan with Camera

Camera Permission

Android

Declare the following permission in your AndroidManifest.xml.

<uses-permission android:name="android.permission.CAMERA"/>
<uses-feature android:name="android.hardware.camera"/>

info

Runtime permission for camera is handled automatically by the Docutain SDK.

iOS

You need to specify the reason for requesting access to the camera as part of the NSCameraUsageDescription in the Info.plist. If you don't the app will crash.

NSCameraUsageDescription

Start Camera Scan

To start the scan process you only have to call DocutainSdkUi.scanDocument and wait for it to return.

An instance of DocumentScannerConfiguration is required to launch the document scanner. It provides the possibility to change some behaviours to adopt it to your needs. See Change default scan behaviour for possible custom settings.

var scanConfig = DocumentScannerConfiguration();
var result = await DocutainSdkUi.scanDocument(scanConfig);
if(result)
{
    //user finished scan process, continue with your workflow
    //generate PDF
    File? pdfFile = await DocutainSdkDocument.writePDF(path, "testPDF");
    //get detected Text
    final text = await DocutainSdkDocumentDataReader.getText();
    //get extracted data 
    final data = await DocutainSdkDocumentDataReader.analyze();
} 
else
{
    //user canceled scan process
}

Scan from imported images

It is also possible to use the Document Scanner on already taken images, for example images selected from the users photo gallery. The process of starting the scanner on imported images is the same as when scanning with the camera. The only difference is defining a different source in the DocumentScannerConfiguration. Possible values are:

camera : This is the default value. Starts the Document Scanner using the devices camera.
image : Starts the Document Scanner on images provided by you via code. Pass sourceImages to the DocumentScannerConfiguration containing the paths to the images to be scanned.
gallery : Opens the user's photo gallery in single select mode. The Document Scanner is run on the selected image.
galleryMultiple : Opens the user's photo gallery in multi select mode. The Document Scanner is run on the selected images.

The following sample shows how to open the photo gallery in multi select mode and run the Document Scanner on the selected images:

var scanConfig = DocumentScannerConfiguration();
scanConfig.source = Source.galleryMultiple;
var result = await DocutainSdkUi.scanDocument(scanConfig);
if(result)
{
    //user finished scan process, continue with your workflow
    //generate PDF
    File? pdfFile = await DocutainSdkDocument.writePDF(path, "testPDF");
    //get detected Text
    final text = await DocutainSdkDocumentDataReader.getText();
    //get extracted data 
    final data = await DocutainSdkDocumentDataReader.analyze();
} 
else
{
    //user canceled scan process
}

Change default scan behaviour

DocumentScannerConfiguration

You can use the DocumentScannerConfiguration to alter the default scan behaviour to your needs. Currently the following values can be set:

Property	Type	Default Value	Description
`allowCaptureModeSetting`	`Boolean`	`false`	If true, the document scanner toolbar will display an item that allows the user to switch between automatic and manual camera triggering.
`autoCapture`	`Boolean`	`true`	If true, the camera will capture the image automatically at the right moment.
`defaultScanFilter`	`ScanFilter`	`illustration`	The default scan filter that will be used after scan.
`onboardingImageSource`	`string`	`empty string`	Your custom image for the onboarding dialog that appears when scan is opened for the first time.
`pageEditConfig`	`PageEditConfiguration`	`PageEditConfiguration`	Configuration class used to alter the default page editing behaviour. See PageEditConfiguration for more details.
`source`	`Source`	`camera`	The source of the Document Scanner. If you need to run the scanner on imported images please see Scan from imported images for more details.
`sourceImages`	`<String>[]`	`empty array`	Please see Scan from imported images for more details.
`autoCrop`	`Boolean`	`true`	If true, image gets automatically cropped if document was detected. This applies only when importing images.
`multiPage`	`Boolean`	`true`	If true, scanning multi page documents is possible. Set this to false if you need to scan single page documents.
`preCaptureFocus`	`Boolean`	`true`	If true, the camera will run a focus action right before taking the image. This improves the quality of the scanned images, but depending on the device, image capture might take a little bit longer.
`textConfig`	`TextConfiguration`	`TextConfiguration`	Configuration class used to alter the default text behaviour. See TextConfiguration for more details.
`buttonConfig`	`ButtonConfiguration`	`ButtonConfiguration`	Configuration class used to alter the default buttons. See ButtonConfiguration for more details.
`colorConfig`	`ColorConfiguration`	`ColorConfiguration`	Configuration class used to alter the default color theming behaviour. See Colorconfiguration for more details.
`confirmPages`	`Boolean`	`false`	If true, a list of all pages (thumbnails) will be displayed before the scan process can be finished.
`allowPageEditing`	`Boolean`	`true`	If true, after the scan screen is finished, an editing screen with the captured images will be displayed. On the editing screen, the user can crop manually, rotate the page, filter the page and much more. The editing screen can be configured by accessing the `PageEditConfiguration`.
`statusBarAppearance`	`StatusBarAppearance`	`null`	Overrides the status bar appearance. By default, the system chooses the appearance based on the current UI Mode. This only applies to Android.
`navigationBarAppearance`	`NavigationBarAppearance`	`null`	Overrides the navigation bar appearance. By default, the system chooses the appearance based on the current UI Mode. This only applies to Android.

info

All parameters in DocumentScannerConfiguration are optional.

The following sample shows how to activate the confirmation mode:

var scanConfig = DocumentScannerConfiguration();
scanConfig.confirmPages = true;
var result = await DocutainSdkUi.scanDocument(scanConfig);

PageEditConfiguration

You can use the PageEditConfiguration to alter the default page editing behaviour of the document scanner to your needs. Currently the following values can be set:

Property	Type	Default Value	Description
`allowPageFilter`	`Boolean`	true	If false, the bottom toolbar will hide the filter page item.
`allowPageRotation`	`Boolean`	true	If false, the bottom toolbar will hide the rotate page item.
`allowPageArrangement`	`Boolean`	true	If false, the bottom toolbar will hide the arrange page item.
`allowPageCropping`	`Boolean`	true	If false, the bottom toolbar will hide the page cropping item.
`allowPageRetake`	`Boolean`	false	If true, the bottom toolbar will show a button allowing to retake the current page.
`pageArrangementShowDeleteButton`	`Boolean`	false	If true, each item of the page arrangement functionality will show a delete button.
`pageArrangementShowPageNumber`	`Boolean`	true	If true, each item of the page arrangement functionality will show it's page number.

info

All parameters in PageEditConfiguration are optional.

The following sample shows how to activate the page retake button:

var scanConfig = DocumentScannerConfiguration();
scanConfig.pageEditConfig.allowPageRetake = true;
var result = await DocutainSdkUi.scanDocument(scanConfig);

TextConfiguration

You can use the TextConfiguration to alter the default text behaviour of the document scanner to your needs. If a value does not get set explicitly, the default value provided by the SDK will be used. If you set a text value to null, it won't show any text. You can use this to remove predefined text. Currently the following values can be set:

Property	Type	Description
`textSizeBottomToolbar`	`double?`	The text size of elements residing in the bottom toolbar.
`textSizeTopToolbar`	`double?`	The text size of menu items residing in the top toolbar.
`textSizeScanButtons`	`double?`	The text size of the buttons in the scan page, located at the lower part, like the torch button.
`textSizeTitle`	`double?`	The text size of the title in the top toolbar. By default, auto shrinking down till 9.0 is enabled. If you define your custom size, automatic shrinking will be disabled.
`textTitleScanPage`	`String?`	The title to be displayed in the scan page top toolbar.
`textTitleEditPage`	`String?`	The title to be displayed in the edit page top toolbar.
`textTitleFilterPage`	`String?`	The title to be displayed in the filter page top toolbar.
`textTitleCroppingPage`	`String?`	The title to be displayed in the cropping page top toolbar.
`textTitleArrangementPage`	`String?`	The title to be displayed in the page arrangement page top toolbar.
`textTitleConfirmationPage`	`String?`	The title to be displayed in the confirmation page top toolbar.
`textDocumentTitle`	`String?`	The title to show in the top toolbar on all pages. It overwrites page specific titles, if any are set.
`textOnboardingTitle`	`String?`	The text to show in the onboarding popup title that appears when the scan page is opened for the first time.
`textOnboardingMessage`	`String?`	The text to show in the onboarding popup message that appears when the scan page is opened for the first time.
`textOnboardingCloseButton`	`String?`	The text to show in the onboarding popup close button that appears when the scan page is opened for the first time.
`textSizeOnboardingTitle`	`double?`	The text size of the onboarding popup title that appears when the scan page is opened for the first time.
`textSizeOnboardingMessage`	`double?`	The text size of the onboarding popup message that appears when the scan page is opened for the first time.
`textFocusHint`	`String?`	The text to show when camera is focusing after capture got triggered.
`textFirstPageHint`	`String?`	The text to show when user swipes to previous page but is already at the first page.
`textLastPageHint`	`String?`	The text to show when user swipes to next page but is already at the last page.
`textOnePageHint`	`String?`	The text to show when user swipes to next or previous page but only one page is available.
`textScanProgress`	`String?`	The text to show in the progress popup that is shown when user clicks the done button but some pages still need to be processed.
`textDeleteDialogCurrentPage`	`String?`	The text to show for the option to delete the current page within the dialog that will be shown when clicking delete while multiple pages are available.
`textDeleteDialogAllPages`	`String?`	The text to show for the option to delete all pages within the dialog that will be shown when clicking delete while multiple pages are available.
`textDeleteDialogCancel`	`String?`	The text to show for the option to cancel within the dialog that will be shown when clicking delete while multiple pages are available.

info

All parameters in TextConfiguration are optional.

The following sample shows how to set a document title:

var scanConfig = DocumentScannerConfiguration();
scanConfig.textConfig.textDocumentTitle = "Document Title";
var result = await DocutainSdkUi.scanDocument(scanConfig);

ButtonConfiguration

You can use the ButtonConfiguration to alter the default buttons of the scanner. Each button is an object of DocutainButton and has a title and icon property. Buttons residing in the top toolbar can have either a title or an icon. If you define both, the icon will be displayed. Buttons residing in the bottom toolbar can have both title and icon at the same time. If you want a button to only display text, set the icon property to an empty string and the title property to the text you want to display. If you want a button to only display an icon, set the text property to an empty string and the icon property to the icon you want to display.

Currently the following buttons can be set:

Button	Default Value	Description
`buttonEditRotate`		The button that rotates the current page.
`buttonEditCrop`		The button that opens the cropping functionality.
`buttonEditFilter`		The button that opens the filter functionality.
`buttonEditArrange`		The button that opens the page arrangement functionality.
`buttonEditRetake`		The button that starts the process of replacing the current page with a new scan.
`buttonEditDelete`		The button that deletes the current page or opens a dialog with options if multiple pages are available.
`buttonEditFinish`		The button that finishes the scan process.
`buttonCropExpand`		The button within the cropping functionality that expands the current cropping rectangle to the whole page.
`buttonCropSnap`		The button within the cropping functionality that snaps the current cropping rectangle to the detected document.
`buttonCropFinish`		The button within the cropping functionality that finishes the manual cropping process according to the current cropping rectangle.
`buttonScanAutoCaptureOn`		The button within the scan functionality that is shown when automatic capture is activated.
`buttonScanAutoCaptureOff`		The button within the scan functionality that is shown when automatic capture is deactivated.
`buttonScanTorch`		The button within the scan functionality that toggles the torch.
`buttonScanCapture`		The button within the scan functionality that triggers a manual image capture.
`buttonScanFinish`		The button within the scan functionality that finishes the current scan process and leads to the editing page.
`buttonConfirmationFinish`		The button on the confirmation page that finishes the scan process.

info

All parameters in ButtonConfiguration are optional.

The following sample shows how to customize the buttonEditRotate:

var scanConfig = DocumentScannerConfiguration();
scanConfig.buttonConfig.buttonEditRotate.title = "title";
scanConfig.buttonConfig.buttonEditRotate.icon = "icon";
var result = await DocutainSdkUi.scanDocument(scanConfig);

ColorConfiguration

In order to fit the Docutain Scanner SDK for Capacitor into your corporate design, you have a bunch of options to alter the default color theming of the ready to use UI components.

Supported colors

The following is a list of all colors currently supported.

Color	Default Value	Description
`colorPrimary`	light: `#4CAF50` dark: `#4CAF50`	Used to tint progress indicators and dialog buttons.
`colorSecondary`	light: `#4CAF50` dark: `#4CAF50`	Used to tint selectable controls and the capture button.
`colorOnSecondary`	light: `#FFFFFF` dark: `#000000`	Used to tint elements that reside on docutain_colorSecondary, like the icon of the capture button.
`colorScanButtonsLayoutBackground`	light: `#121212` dark: `#121212`	Used to tint the background of the scan buttons layout.
`colorScanButtonsForeground`	light: `#FFFFFF` dark: `#FFFFFF`	Used to tint the foreground of the scan buttons layout, like the torch button.
`colorScanPolygon`	light: `#4CAF50` dark: `#4CAF50`	Used to tint the polygon overlay which highlights the currently detected document.
`colorBottomBarBackground`	light: `#FFFFFF` dark: `#212121`	Used to tint the bottom toolbar background of the image editing page.
`colorBottomBarForeground`	light: `#323232` dark: `#BEBEBE`	Used to tint the buttons within the bottom toolbar of the image editing page.
`colorTopBarBackground`	light: `#4CAF50` dark: `#2a2a2a`	Used to tint the top toolbar background.
`colorTopBarForeground`	light: `#FFFFFF` dark: `#DEFFFFFF`	Used to tint the buttons contained in the top toolbar.

Dark Mode

The Docutain Scanner SDK for Capacitor also supports dark mode theming. The process is the same, just define different colors for the night version of your theme. The SDK decides which color to use depending on the device's sytem setting and it will change at runtime, if the device's display mode changes.

theming_edit_bottombar theming_edit_bottombar_dark

Defining a custom theme

In order to alter at least one of the colors mentioned above, you need to pass it to the DocumentScannerConfiguration which is used to start the ready to use UI Scan components.

The following is an example which alters all currently available colors.

import 'package:tuple/tuple.dart';

var scanConfig = DocumentScannerConfiguration();
//define your colors
scanConfig.colorConfig.colorPrimary = const Tuple2<Color, Color>(Colors.purple, Colors.purple);
scanConfig.colorConfig.colorSecondary = const Tuple2<Color, Color>(Colors.purple, Colors.purple);
scanConfig.colorConfig.colorOnSecondary = const Tuple2<Color, Color>(Colors.white, Colors.black);
scanConfig.colorConfig.colorScanButtonsLayoutBackground = const Tuple2<Color, Color>(Colors.white, Colors.black);
scanConfig.colorConfig.colorScanButtonsForeground = const Tuple2<Color, Color>(Colors.black, Colors.white);
scanConfig.colorConfig.colorScanPolygon = const Tuple2<Color, Color>(Colors.purple, Colors.purple);
scanConfig.colorConfig.colorBottomBarBackground = const Tuple2<Color, Color>(Colors.purple, Colors.black);
scanConfig.colorConfig.colorBottomBarForeground = const Tuple2<Color, Color>(Colors.white, Colors.white);
scanConfig.colorConfig.colorTopBarBackground = const Tuple2<Color, Color>(Colors.purple, Colors.black);
scanConfig.colorConfig.colorTopBarForeground = const Tuple2<Color, Color>(Colors.white, Colors.white);
//start the scanner
bool rcScan = await DocutainSdkUi.scanDocument(scanConfig);

Result handling

After the scan process is successfully finished, you can do a bunch of things with the scanned pages:

Flutter PDF Creation

Flutter Image Export

Flutter Text Recognition

Flutter Data Extraction

Document Scan

Initialization​

Scan with Camera​

Camera Permission​

Android​

iOS​

Start Camera Scan​

Scan from imported images​

Change default scan behaviour​

DocumentScannerConfiguration​

PageEditConfiguration​

TextConfiguration​

ButtonConfiguration​

ColorConfiguration​

Supported colors​

Dark Mode​

Defining a custom theme​

Result handling​

Initialization

Scan with Camera

Camera Permission

Android

iOS

Start Camera Scan

Scan from imported images

Change default scan behaviour

DocumentScannerConfiguration

PageEditConfiguration

TextConfiguration

ButtonConfiguration

ColorConfiguration

Supported colors

Dark Mode

Defining a custom theme

Result handling