scandit-sdk
Version:
Scandit Barcode Scanner SDK for the Web
804 lines (803 loc) • 41.6 kB
TypeScript
import { ListenerFn } from "eventemitter3";
import { Camera } from "../camera";
import { CameraSettings } from "../cameraSettings";
import { Parser } from "../parser";
import { Scanner } from "../scanner";
import { ScanResult } from "../scanResult";
import { ScanSettings } from "../scanSettings";
import { SearchArea } from "../searchArea";
import { SingleImageModeSettings } from "../singleImageModeSettings";
/**
* @hidden
*/
declare type EventName = "ready" | "submitFrame" | "processFrame" | "scan" | "scanError" | "cameraAccessError";
/**
* A barcode picker element used to get and show camera input and perform scanning operations.
*
* The barcode picker will automatically fit and scale inside the given *originElement*.
*
* Each barcode picker internally contains a [[Scanner]] object with its own WebWorker thread running a
* separate copy of the external Scandit Data Capture library. To optimize loading times and performance it's
* recommended to reuse the same picker and to already create the picker in advance (hidden) and just
* display it when needed whenever possible.
*
* As the loading of the external Scandit Data Capture library can take some time, the picker always starts inactive
* (but showing GUI and video) and then activates, if not paused, as soon as the library is ready to scan.
* The [[on]] method targeting the [[ready]] event can be used to set up a listener function to be called when the
* library is loaded. The picker will be ready to start scanning when the library is fully loaded.
*
* By default the external Scandit Data Capture library is preloaded in order to reduce the initialization time as much
* as possible.
*
* The picker can also operate in Single Image Mode: letting the user click/tap to take a single image to be scanned
* via the camera (mobile) or a file select dialog (desktop). This is provided automatically as fallback by
* default when the OS/browser only supports part of the needed features and cannot provide direct access to the camera
* for video streaming and continuous scanning, or can also be forced on/off. This behaviour can be set up on creation
* via the *singleImageModeSettings* option. Note that in this mode some of the functions provided by the picker will
* have no effect.
*
* By default an alert is shown if an internal error during scanning is encountered which prevents the scanning
* procedure from continuing when running on a local IP address. As this uses the built-in [[scanError]] event
* functionality, if unwanted it can be disabled by calling [[removeAllListeners]] on the BarcodePicker
* instance (right after creation).
*
* In accordance with our license terms, the Scandit logo displayed in the bottom right corner of the barcode picker
* must be displayed and cannot be hidden by any method. Workarounds are not allowed.
*/
export declare class BarcodePicker {
private readonly cameraManager;
private readonly gui;
private readonly eventEmitter;
private readonly scanner;
private readonly beepSound;
private readonly vibrateFunction?;
private readonly scannerReadyEventListener;
private playSoundOnScan;
private vibrateOnScan;
private scanningPaused;
private latestVideoTimeProcessed;
private destroyed;
private isReadyToWork;
private cameraAccess;
private targetScanningFPS;
private averageProcessingTime;
private externalImageData;
private internalImageData?;
private constructor();
/**
* Fired when the external Scandit Data Capture library has been loaded and the barcode picker can thus start to scan
* barcodes or texts.
*
* @asMemberOf BarcodePicker
* @event
*/
static ready(): void;
/**
* Fired when a new frame is submitted to the external Scandit Data Capture library to be processed. As the frame is
* not processed yet, the [[ScanResult.barcodes]] property will always be empty (no results yet).
*
* @asMemberOf BarcodePicker
* @event
* @param scanResult The result of the scanning operation on the image.
*/
static submitFrame(scanResult: ScanResult): void;
/**
* Fired when a new frame is processed by the external Scandit Data Capture library. This event is fired on every
* frame, independently from the number of recognized barcodes or texts (can both be none). The returned barcodes and
* texts are affected by [[ScanSettings]]'s *codeDuplicateFilter* and [[TextRecognitionSettings]]'s
* *textDuplicateFilter* options.
*
* @asMemberOf BarcodePicker
* @event
* @param scanResult The result of the scanning operation on the image.
*/
static processFrame(scanResult: ScanResult): void;
/**
* Fired when new barcodes or texts are recognized in the image frame. The returned barcodes and texts are affected by
* [[ScanSettings]]'s *codeDuplicateFilter* and [[TextRecognitionSettings]]'s *textDuplicateFilter* options.
*
* @asMemberOf BarcodePicker
* @event
* @param scanResult The result of the scanning operation on the image.
*/
static scan(scanResult: ScanResult): void;
/**
* Fired when an error occurs during scanning initialization and execution. The barcode picker will be automatically
* paused when this happens.
*
* @asMemberOf BarcodePicker
* @event
* @param error The ScanditEngineError that was triggered.
*/
static scanError(error: Error): void;
/**
* Fired when an error occurs during camera access.
*
* @asMemberOf BarcodePicker
* @event
* @param error The Error that was triggered.
*/
static cameraAccessError(error: Error): void;
/**
* Create a [[BarcodePicker]] instance, creating the needed HTML in the given origin element.
* If the *accessCamera* option is enabled (active by default) and the picker is not in Single Image Mode,
* the available cameras are accessed and camera access permission is requested to the user if needed.
* This object expects that at least a camera is available. The active camera is accessed and kept active during the
* lifetime of the picker (also when hidden or scanning is paused), and is only released when [[destroy]] is called.
*
* It is required to having configured the library via [[configure]] before this object can be created.
*
* Depending on library configuration, parameters, device/browser features and user permissions for camera access, any
* of the following errors could be the rejected result of the returned promise:
* - `AbortError`
* - `LibraryNotConfiguredError`
* - `NoCameraAvailableError`
* - `NoOriginElementError`
* - `NotAllowedError`
* - `NotFoundError`
* - `NotReadableError`
* - `SecurityError`
* - `UnsupportedBrowserError`
*
* @param originElement The HTMLElement inside which all the necessary elements for the picker will be added.
* @param visible <div class="tsd-signature-symbol">Default = true</div>
* Whether the picker starts in a visible state.
* @param singleImageModeSettings <div class="tsd-signature-symbol">Default = </div>
* <pre><code>{
* desktop: {
* usageStrategy: SingleImageModeSettings.UsageStrategy.FALLBACK,
* informationElement: <HTMLElement>,
* buttonElement: <SVGElement>,
* containerStyle: { backgroundColor: "#333333" },
* informationStyle: { color: "#FFFFFF" },
* buttonStyle: { borderColor: "#FFFFFF", color: "#FFFFFF", fill: "#FFFFFF" }
* },
* mobile: {
* usageStrategy: SingleImageModeSettings.UsageStrategy.FALLBACK,
* informationElement: <HTMLElement>,
* buttonElement: <SVGElement>,
* containerStyle: { backgroundColor: "#333333" },
* informationStyle: { color: "#FFFFFF" },
* buttonStyle: { borderColor: "#FFFFFF", color: "#FFFFFF", fill: "#FFFFFF" }
* }
* }</code></pre>
* Settings for Single Image Mode: an alternative/fallback mode for a barcode picker to provide single camera
* pictures to be scanned instead of continuous camera video stream access. In Single Image Mode users click/tap to
* directly take a picture with the camera (mobile) or upload a file (desktop). Its usage depends on the given
* settings and the camera video stream features provided by the OS/browser.
* @param playSoundOnScan <div class="tsd-signature-symbol">Default = false</div>
* Whether a sound is played on barcode/text recognition (iOS requires user input).
* @param vibrateOnScan <div class="tsd-signature-symbol">Default = false</div>
* Whether the device vibrates on barcode/text recognition (only Chrome & Firefox, requires user input).
* @param scanningPaused <div class="tsd-signature-symbol">Default = false</div>
* Whether the picker starts in a paused scanning state.
* @param guiStyle <div class="tsd-signature-symbol">Default = GuiStyle.LASER</div>
* The GUI style for the picker.
* @param videoFit <div class="tsd-signature-symbol">Default = ObjectFit.CONTAIN</div>
* The fit type for the video element of the picker.
* @param cameraRecoveryText <div class="tsd-signature-symbol">Default = "Tap/click to resume scanning"</div>
* The text to display to indicate to the user a necessary tap/click action on the picker to recover camera access.
* @param laserArea <div class="tsd-signature-symbol">Default = undefined</div>
* The area of the laser displayed when the GUI style is set to <em>laser</em> (the laser will match the width and be
* vertically centered), by default the area will match the current [[ScanSettings]]'s <em>searchArea</em> option.
* @param viewfinderArea <div class="tsd-signature-symbol">Default = undefined</div>
* The area of the viewfinder displayed when the GUI style is set to <em>viewfinder</em>, by default the area will
* match the current [[ScanSettings]]'s <em>searchArea</em> option.
* @param enableCameraSwitcher <div class="tsd-signature-symbol">Default = true</div>
* Whether to show a GUI button to switch between different cameras (when available).
* @param enableTorchToggle <div class="tsd-signature-symbol">Default = true</div>
* Whether to show a GUI button to toggle device torch on/off (when available, only Chrome).
* @param enableTapToFocus <div class="tsd-signature-symbol">Default = true</div>
* Whether to trigger a manual focus of the camera when clicking/tapping on the video (when available, only Chrome).
* @param enablePinchToZoom <div class="tsd-signature-symbol">Default = true</div>
* Whether to control the zoom of the camera when doing a pinching gesture on the video (when available, only Chrome).
* @param accessCamera <div class="tsd-signature-symbol">Default = true</div>
* Whether to immediately access the camera (and requesting user permissions if needed) on picker creation.
* @param camera <div class="tsd-signature-symbol">Default = undefined</div>
* The initial camera to be used for video input, if not specified the camera automatically selected depending on
* the <em>cameraType</em> option will be used.
* @param cameraType <div class="tsd-signature-symbol">Default = Camera.Type.BACK</div>
* The preferred initial camera type (facing mode/direction) to be used for video input and Single Image Mode
* (when available), by default the back or only camera will be used. If the <em>camera</em> option is provided then
* <em>cameraType</em> is ignored.
* @param cameraSettings <div class="tsd-signature-symbol">Default = undefined</div>
* The camera options used when accessing the camera, by default <code>hd</code> resolution is used.
* @param scanner <div class="tsd-signature-symbol">Default = undefined</div>
* The scanner object responsible for scanning via the external Scandit Data Capture library
* (a new scanner will be created and initialized if not provided).
* @param scanSettings <div class="tsd-signature-symbol">Default = new ScanSettings()</div>
* The configuration object for scanning options to be applied to the scanner (all symbologies disabled by default).
* @param targetScanningFPS <div class="tsd-signature-symbol">Default = 30</div>
* The target frames per second to be processed, the final speed is limited by the camera framerate (usually 30 FPS)
* and the frame processing time of the device. By setting this to lower numbers devices can save power by performing
* less work during scanning operations, depending on device speed (faster devices can "sleep" for longer periods).
* Must be a number bigger than 0.
* @returns A promise resolving to the created ready [[BarcodePicker]] object.
*/
static create(originElement: HTMLElement, { visible, singleImageModeSettings, playSoundOnScan, vibrateOnScan, scanningPaused, guiStyle, videoFit, cameraRecoveryText, laserArea, viewfinderArea, scanner, scanSettings, enableCameraSwitcher, enableTorchToggle, enableTapToFocus, enablePinchToZoom, accessCamera, camera, cameraType, cameraSettings, targetScanningFPS,
/**
* @hidden
*/
hideLogo, }?: {
visible?: boolean;
singleImageModeSettings?: SingleImageModeSettings;
playSoundOnScan?: boolean;
vibrateOnScan?: boolean;
scanningPaused?: boolean;
guiStyle?: BarcodePicker.GuiStyle;
videoFit?: BarcodePicker.ObjectFit;
cameraRecoveryText?: string;
laserArea?: SearchArea;
viewfinderArea?: SearchArea;
scanner?: Scanner;
scanSettings?: ScanSettings;
enableCameraSwitcher?: boolean;
enableTorchToggle?: boolean;
enableTapToFocus?: boolean;
enablePinchToZoom?: boolean;
accessCamera?: boolean;
camera?: Camera;
cameraType?: Camera.Type;
cameraSettings?: CameraSettings;
targetScanningFPS?: number;
/**
* @hidden
*/
hideLogo?: boolean;
}): Promise<BarcodePicker>;
/**
* Stop scanning and displaying video output, remove HTML elements added to the page,
* destroy the internal [[Scanner]] (by default) and destroy the barcode picker itself; ensuring complete cleanup.
*
* This method should be called after you don't plan to use the picker anymore,
* before the object is automatically cleaned up by JavaScript.
* The barcode picker must not be used in any way after this call.
*
* If the [[Scanner]] is or will be in use for other purposes, the relative option can be passed to prevent
* its destruction.
*
* @param destroyScanner Whether to destroy the internally used [[Scanner]] or not.
*/
destroy(destroyScanner?: boolean): void;
/**
* Apply a new set of scan settings to the internal scanner (replacing old settings).
*
* @param scanSettings The scan configuration object to be applied to the scanner.
* @returns The updated [[BarcodePicker]] object.
*/
applyScanSettings(scanSettings: ScanSettings): BarcodePicker;
/**
* @returns Whether the scanning is currently paused.
*/
isScanningPaused(): boolean;
/**
* Pause the recognition of codes/texts in the input image.
*
* By default video from the camera is still shown, if the *pauseCamera* option is enabled the camera stream
* is paused (camera access is fully interrupted) and will be resumed when calling [[resumeScanning]],
* [[setActiveCamera]], [[setCameraType]] or [[accessCamera]], possibly requesting user permissions if needed.
*
* In Single Image Mode the input for submitting a picture is disabled.
*
* @param pauseCamera Whether to also pause the camera stream.
* @returns The updated [[BarcodePicker]] object.
*/
pauseScanning(pauseCamera?: boolean): BarcodePicker;
/**
* Resume the recognition of codes/texts in the input image.
*
* If the camera stream was stopped when calling [[pauseScanning]], the camera stream is also resumed and
* user permissions are requested if needed to resume video input.
*
* In Single Image Mode the input for submitting a picture is enabled.
*
* @returns The updated [[BarcodePicker]] object.
*/
resumeScanning(): Promise<BarcodePicker>;
/**
* @returns The currently active camera.
*/
getActiveCamera(): Camera | undefined;
/**
* Select a camera to be used for video input, if no camera is passed, the default one (based on *cameraType*) is
* selected.
*
* If camera access is enabled, the camera is enabled and accessed. If not, the camera is stored and used for the
* future initial camera access.
*
* Depending on device features and user permissions for camera access, any of the following errors
* could be the rejected result of the returned promise:
* - `AbortError`
* - `NoCameraAvailableError`
* - `NotAllowedError`
* - `NotFoundError`
* - `NotReadableError`
* - `SecurityError`
*
* In Single Image Mode this method has no effect.
*
* @param camera The new camera to be used, by default the automatically detected back camera is used.
* @param cameraSettings The camera options used when accessing the camera, by default `hd` resolution is used.
* @returns A promise resolving to the updated [[BarcodePicker]] object when the camera is set
* (and accessed, if camera access is currently enabled).
*/
setActiveCamera(camera?: Camera, cameraSettings?: CameraSettings): Promise<BarcodePicker>;
/**
* Select a camera to be used for video input by specifying the wanted camera type (facing mode/direction): the main
* camera detected for the given camera type will be used.
*
* If camera access is enabled, the camera is enabled and accessed. If not, the camera type is stored and used for the
* future initial camera access.
*
* If the target camera is already in use or no camera with the given type is found this method has no effect.
*
* Depending on device features and user permissions for camera access, any of the following errors
* could be the rejected result of the returned promise:
* - `AbortError`
* - `NoCameraAvailableError`
* - `NotAllowedError`
* - `NotFoundError`
* - `NotReadableError`
* - `SecurityError`
*
* @param cameraType The new camera type (facing mode/direction) to be used for video input and Single Image Mode
* (when available).
* @returns A promise resolving to the updated [[BarcodePicker]] object when the camera is updated
* (and accessed, if camera access is currently enabled).
*/
setCameraType(cameraType: Camera.Type): Promise<BarcodePicker>;
/**
* Try to apply new settings to the currently used camera for video input,
* if no settings are passed the default ones are set.
*
* If camera access is enabled, the camera is updated and accessed with the new settings. If not, the camera settings
* are stored and used for the future initial camera access.
*
* Depending on device features and user permissions for camera access, any of the following errors
* could be the rejected result of the returned promise:
* - `AbortError`
* - `NoCameraAvailableError`
* - `NotAllowedError`
* - `NotFoundError`
* - `NotReadableError`
* - `SecurityError`
*
* In Single Image Mode this method has no effect.
*
* @param cameraSettings The new camera options used when accessing the camera, by default `hd` resolution is used.
* @returns A promise resolving to the updated [[BarcodePicker]] object when the camera is updated
* (and accessed, if camera access is currently enabled).
*/
applyCameraSettings(cameraSettings?: CameraSettings): Promise<BarcodePicker>;
/**
* @returns Whether the picker is in a visible state or not.
*/
isVisible(): boolean;
/**
* Enable or disable picker visibility.
*
* Note that this does not affect camera access, frame processing or any other picker logic.
*
* @param visible Whether the picker is in a visible state or not.
* @returns The updated [[BarcodePicker]] object.
*/
setVisible(visible: boolean): BarcodePicker;
/**
* @returns Whether the currently selected camera's video is mirrored along the vertical axis.
*/
isMirrorImageEnabled(): boolean;
/**
* Enable or disable camera video mirroring along the vertical axis.
* By default front cameras are automatically mirrored.
* This setting is applied per camera and the method has no effect if no camera is currently selected.
*
* In Single Image Mode this method has no effect.
*
* @param enabled Whether the camera video is mirrored along the vertical axis.
* @returns The updated [[BarcodePicker]] object.
*/
setMirrorImageEnabled(enabled: boolean): BarcodePicker;
/**
* @returns Whether a sound should be played on barcode/text recognition (iOS requires user input).
* Note that the sound is played if there's at least a barcode or text not rejected via [[ScanResult.rejectCode]] or
* [[ScanResult.rejectText]].
*/
isPlaySoundOnScanEnabled(): boolean;
/**
* Enable or disable playing a sound on barcode/text recognition (iOS requires user input).
*
* The sound is played if there's at least a barcode or text not rejected via [[ScanResult.rejectCode]] or
* [[ScanResult.rejectText]].
*
* @param enabled Whether a sound should be played on barcode/text recognition.
* @returns The updated [[BarcodePicker]] object.
*/
setPlaySoundOnScanEnabled(enabled: boolean): BarcodePicker;
/**
* @returns Whether the device should vibrate on barcode/text recognition (only Chrome & Firefox, requires user
* input).
* Note that the vibration is triggered if there's at least a barcode or text not rejected via
* [[ScanResult.rejectCode]] or [[ScanResult.rejectText]].
*/
isVibrateOnScanEnabled(): boolean;
/**
* Enable or disable vibrating the device on barcode/text recognition (only Chrome & Firefox, requires user input).
*
* The vibration is triggered if there's at least a barcode or text not rejected via [[ScanResult.rejectCode]] or
* [[ScanResult.rejectText]].
*
* @param enabled Whether the device should vibrate on barcode/text recognition.
* @returns The updated [[BarcodePicker]] object.
*/
setVibrateOnScanEnabled(enabled: boolean): BarcodePicker;
/**
* @returns Whether a GUI button to switch between different cameras is shown (when available).
*/
isCameraSwitcherEnabled(): boolean;
/**
* Show or hide a GUI button to switch between different cameras (when available).
*
* In Single Image Mode this method has no effect.
*
* @param enabled Whether to show a GUI button to switch between different cameras.
* @returns The updated [[BarcodePicker]] object.
*/
setCameraSwitcherEnabled(enabled: boolean): BarcodePicker;
/**
* @returns Whether a GUI button to toggle device torch on/off is shown (when available, only Chrome).
*/
isTorchToggleEnabled(): boolean;
/**
* Show or hide a GUI button to toggle device torch on/off (when available, only Chrome).
*
* In Single Image Mode this method has no effect.
*
* @param enabled Whether to show a GUI button to toggle device torch on/off.
* @returns The updated [[BarcodePicker]] object.
*/
setTorchToggleEnabled(enabled: boolean): BarcodePicker;
/**
* @returns Whether manual camera focus when clicking/tapping on the video is enabled (when available, only Chrome).
*/
isTapToFocusEnabled(): boolean;
/**
* Enable or disable manual camera focus when clicking/tapping on the video (when available, only Chrome).
*
* In Single Image Mode this method has no effect.
*
* @param enabled Whether to enable manual camera focus when clicking/tapping on the video.
* @returns The updated [[BarcodePicker]] object.
*/
setTapToFocusEnabled(enabled: boolean): BarcodePicker;
/**
* @returns Whether camera zoom control via pinching gesture on the video is enabled (when available, only Chrome).
*/
isPinchToZoomEnabled(): boolean;
/**
* Enable or disable camera zoom control via pinching gesture on the video (when available, only Chrome).
*
* In Single Image Mode this method has no effect.
*
* @param enabled Whether to enable camera zoom control via pinching gesture on the video.
* @returns The updated [[BarcodePicker]] object.
*/
setPinchToZoomEnabled(enabled: boolean): BarcodePicker;
/**
* Enable or disable the torch/flashlight of the device (when available, only Chrome).
* Changing active camera or camera settings will cause the torch to become disabled.
*
* A button on the [[BarcodePicker]] GUI to let the user toggle this functionality can also be set
* on creation via the *enableTorchToggle* option (enabled by default, when available).
*
* In Single Image Mode this method has no effect.
*
* @param enabled Whether the torch should be enabled or disabled.
* @returns A promise resolving to the updated [[BarcodePicker]] object when the torch is enabled/disabled.
*/
setTorchEnabled(enabled: boolean): Promise<BarcodePicker>;
/**
* Set the zoom level of the device (when available, only Chrome).
* Changing active camera or camera settings will cause the zoom to be reset.
*
* In Single Image Mode this method has no effect.
*
* @param zoomPercentage The percentage of the max zoom (between 0 and 1).
* @returns The updated [[BarcodePicker]] object.
*/
setZoom(zoomPercentage: number): Promise<BarcodePicker>;
/**
* @returns Whether the barcode picker has loaded the external Scandit Data Capture library and is ready to scan.
*/
isReady(): boolean;
/**
* Add the listener function to the listeners array for an event.
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: EventName, listener: ListenerFn, once?: boolean): BarcodePicker;
/**
* Add the listener function to the listeners array for the [[ready]] event, fired when the external
* Scandit Data Capture library has been loaded and the barcode picker can thus start to scan barcodes or texts.
* If the library has already been loaded the listener is called immediately.
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: "ready", listener: () => void): BarcodePicker;
/**
* Add the listener function to the listeners array for the [[submitFrame]] event, fired when a new frame is submitted
* to the external Scandit Data Capture library to be processed. As the frame is not processed yet, the
* [[ScanResult.barcodes]] and [[ScanResult.texts]] properties will always be empty (no results yet).
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function, which will be invoked with a [[ScanResult]] object.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: "submitFrame", listener: (scanResult: ScanResult) => void, once?: boolean): BarcodePicker;
/**
* Add the listener function to the listeners array for the [[processFrame]] event, fired when a new frame is
* processed. This event is fired on every frame, independently from the number of recognized barcodes or texts (can
* both be none). The returned barcodes and texts are affected by [[ScanSettings]]'s *codeDuplicateFilter* and
* [[TextRecognitionSettings]]'s *textDuplicateFilter* options.
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function, which will be invoked with a [[ScanResult]] object.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: "processFrame", listener: (scanResult: ScanResult) => void, once?: boolean): BarcodePicker;
/**
* Add the listener function to the listeners array for the [[scan]] event, fired when new barcodes or texts
* are recognized in the image frame. The returned barcodes and texts are affected by [[ScanSettings]]'s
* *codeDuplicateFilter* and [[TextRecognitionSettings]]'s *textDuplicateFilter* options.
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function, which will be invoked with a [[ScanResult]] object.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: "scan", listener: (scanResult: ScanResult) => void, once?: boolean): BarcodePicker;
/**
* Add the listener function to the listeners array for the [[scanError]] event, fired when an error occurs
* during scanning initialization and execution. The barcode picker will be automatically paused when this happens.
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function, which will be invoked with an `ScanditEngineError` object.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: "scanError", listener: (error: Error) => void, once?: boolean): BarcodePicker;
/**
* Add the listener function to the listeners array for the [[cameraAccessError]] event, fired when an error occurs
* during camera access..
*
* No checks are made to see if the listener has already been added.
* Multiple calls passing the same listener will result in the listener being added, and called, multiple times.
*
* @param eventName The name of the event to listen to.
* @param listener The listener function, which will be invoked with an `Error` object.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
on(eventName: "cameraAccessError", listener: (error: Error) => void, once?: boolean): BarcodePicker;
/**
* Remove the specified listener from the given event's listener array.
*
* @param eventName The name of the event from which to remove the listener.
* @param listener The listener function to be removed.
* @returns The updated [[BarcodePicker]] object.
*/
removeListener(eventName: EventName, listener: ListenerFn): BarcodePicker;
/**
* Remove all listeners from the given event's listener array.
*
* @param eventName The name of the event from which to remove all listeners.
* @returns The updated [[BarcodePicker]] object.
*/
removeAllListeners(eventName: EventName): BarcodePicker;
/**
* *See the [[on]] method.*
*
* @param eventName The name of the event to listen to.
* @param listener The listener function.
* @param once <div class="tsd-signature-symbol">Default = false</div>
* Whether the listener should just be triggered only once and then discarded.
* @returns The updated [[BarcodePicker]] object.
*/
addListener(eventName: EventName, listener: ListenerFn, once?: boolean): BarcodePicker;
/**
* Set the GUI style for the picker.
*
* In Single Image Mode this method has no effect.
*
* When the GUI style is set to *laser* or *viewfinder*, the GUI will flash on barcode/text recognition.
* Note that the GUI will flash if there's at least a barcode or text not rejected via [[ScanResult.rejectCode]] or
* [[ScanResult.rejectText]].
*
* @param guiStyle The new GUI style to be applied.
* @returns The updated [[BarcodePicker]] object.
*/
setGuiStyle(guiStyle: BarcodePicker.GuiStyle): BarcodePicker;
/**
* Set the fit type for the video element of the picker.
*
* If the "cover" type is selected the maximum available search area for barcode/text detection is (continuously)
* adjusted automatically according to the visible area of the picker.
*
* In Single Image Mode this method has no effect.
*
* @param objectFit The new fit type to be applied.
* @returns The updated [[BarcodePicker]] object.
*/
setVideoFit(objectFit: BarcodePicker.ObjectFit): BarcodePicker;
/**
* Access the currently set or default camera, requesting user permissions if needed.
* This method is meant to be used after the picker has been initialized with disabled camera access
* (*accessCamera*=false) or after [[pauseScanning]] has been called with the pause camera stream option.
* Calling this doesn't do anything if the camera is already being accessed.
*
* Depending on device features and user permissions for camera access, any of the following errors
* could be the rejected result of the returned promise:
* - `AbortError`
* - `NoCameraAvailableError`
* - `NotAllowedError`
* - `NotFoundError`
* - `NotReadableError`
* - `SecurityError`
*
* In Single Image Mode this method has no effect.
*
* @returns A promise resolving to the updated [[BarcodePicker]] object when the camera is accessed.
*/
accessCamera(): Promise<BarcodePicker>;
/**
* Create a new parser object.
*
* @param dataFormat The format of the input data for the parser.
* @returns The newly created parser.
*/
createParserForFormat(dataFormat: Parser.DataFormat): Parser;
/**
* Reassign the barcode picker to a different HTML element.
*
* All the barcode picker elements inside the current origin element will be moved to the new given one.
*
* If an invalid element is given, a `NoOriginElementError` error is thrown.
*
* @param originElement The HTMLElement into which all the necessary elements for the picker will be moved.
* @returns The updated [[BarcodePicker]] object.
*/
reassignOriginElement(originElement: HTMLElement): BarcodePicker;
/**
* Set the target frames per second to be processed by the external Scandit Data Capture library.
*
* The final speed is limited by the camera framerate (usually 30 FPS) and the frame processing time of the device.
* By setting this to lower numbers devices can save power by performing less work during scanning operations,
* depending on device speed (faster devices can "sleep" for longer periods).
*
* In Single Image Mode this method has no effect.
*
* @param targetScanningFPS The target frames per second to be processed.
* Must be a number bigger than 0, by default set to 30.
* @returns The updated [[BarcodePicker]] object.
*/
setTargetScanningFPS(targetScanningFPS: number): BarcodePicker;
/**
* @returns The internally used initialized (and possibly configured) [[Scanner]] object instance.
*/
getScanner(): Scanner;
/**
* Clear the internal scanner session.
*
* This removes all recognized barcodes/texts from the scanner session and allows them to be scanned again in case a
* custom *codeDuplicateFilter* and/or *textDuplicateFilter* option was set in [[ScanSettings]] or
* [[TextRecognitionSettings]].
*
* @returns The updated [[BarcodePicker]] object.
*/
clearSession(): BarcodePicker;
/**
* Set the area of the laser displayed when the GUI style is set to *laser* (the laser will match the width and be
* vertically centered).
* Note that this functionality affects UI only and doesn't change the actual *searchArea* option set via
* [[ScanSettings]]. If no area is passed, the default automatic size behaviour is set, where the laser will match
* the current area of the image in which barcodes/texts are searched, controlled via the *searchArea* option in
* [[ScanSettings]].
*
* @param area The new search area, by default the area will match [[ScanSettings]]'s *searchArea* option.
* @returns The updated [[BarcodePicker]] object.
*/
setLaserArea(area?: SearchArea): BarcodePicker;
/**
* Set the area of the viewfinder displayed when the GUI style is set to *viewfinder*.
* Note that this functionality affects UI only and doesn't change the actual search area set via [[ScanSettings]].
* If no area is passed, the default automatic size behaviour is set, where the viewfinder will match the current area
* of the image in which barcodes/texts are searched, controlled via the *searchArea* option in [[ScanSettings]].
*
* @param area The new search area, by default the area will match the [[ScanSettings]]'s *searchArea*.
* @returns The updated [[BarcodePicker]] object.
*/
setViewfinderArea(area?: SearchArea): BarcodePicker;
/**
* @hidden
*
* Pause the camera stream (camera access is fully interrupted).
*
* @returns The updated [[BarcodePicker]] object.
*/
pauseCameraAccess(): BarcodePicker;
private triggerCameraAccessError;
private handleScanResult;
private scheduleVideoProcessing;
private scheduleNextVideoProcessing;
private processVideoFrame;
private videoProcessing;
private handleScannerReady;
}
export declare namespace BarcodePicker {
/**
* GUI style to be used by a barcode picker, used to hint barcode/text placement in the frame.
*/
enum GuiStyle {
/**
* No GUI is shown to indicate where the barcode/text should be placed.
* Be aware that the Scandit logo continues to be displayed as showing it is part of the license agreement.
*/
NONE = "none",
/**
* A laser line is shown.
*/
LASER = "laser",
/**
* A rectangular viewfinder with rounded corners is shown.
*/
VIEWFINDER = "viewfinder"
}
/**
* Fit type used to control the resizing (scale) of the barcode picker to fit in its container *originElement*.
*/
enum ObjectFit {
/**
* Scale to maintain aspect ratio while fitting within the *originElement*'s content box.
* Aspect ratio is preserved, so the barcode picker will be "letterboxed" if its aspect ratio
* does not match the aspect ratio of the box.
*/
CONTAIN = "contain",
/**
* Scale to maintain aspect ratio while filling the *originElement*'s entire content box.
* Aspect ratio is preserved, so the barcode picker will be clipped to fit if its aspect ratio
* does not match the aspect ratio of the box.
*/
COVER = "cover"
}
}
export {};