# {RemoteScanObject} > The methods and events on this page live in {RemoteScanObject}. --- ## Scanner **Method** ### getServices Get all active Dynamic Web TWAIN Services. **Syntax** ```typescript getServices(forceRefresh?: boolean): Promise;; ``` **Parameters** `forceRefresh`: Default value is false. --- ### getDevices Based on parameters, return all eligible scan devices. **Syntax** ```typescript getDevices(deviceQueryParams?:{serviceInfo?: ServiceInfo, deviceType?: Dynamsoft.DWT.EnumDWT_DeviceType, refresh?: boolean}): Promise; ``` **Parameters** `serviceInfo`: The service information. Please refer to [ServiceInfo](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#serviceinfo). `deviceType`: The value to filter scanners. Default: TWAINSCANNER. Please refer to [EnumDWT_DeviceType](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_devicetype). `refresh`: Default value is false. --- ### acquireImage Scan documents into RemoteScanObject. **Syntax** ```typescript acquireImage(device: Device, deviceConfiguration?: DeviceConfiguration) : Promise; ``` **Parameters** `deviceConfiguration`: The device configuration. Please refer to [DeviceConfiguration](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#deviceconfiguration) --- ### setDefaultService Set the default service which is used to store the scanned image data. **Syntax** ```typescript setDefaultService(serviceInfo: ServiceInfo):Promise; ``` **Parameters** `serviceInfo`: The service information. Please refer to [ServiceInfo](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#serviceinfo). **Remark** If the specified service is not working, the default service will keep to the last set one. If the default service is never set, it will return `null`. If `setDefaultService` is not called, the default service will be set to the first working service automatically when scanning. --- ### getDefaultService Get the default service info. **Syntax** ```typescript getDefaultService(): ServiceInfo|null; ``` --- ### getCapabilities Gets detailed information about all capabilities of the current data source. **Syntax** ```typescript getCapabilities(device: Device): Promise; ``` **Parameters** `device`: Please refer to [Device](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#device). **Argument** `CapabilityDetails`: Please refer to [CapabilityDetails](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#capabilitydetails). --- ### setCapabilities Sets up one or multiple capabilities in one call. **Syntax** ```typescript setCapabilities(device: Device, capabilities: Capabilities): Promise; ``` **Parameters** `device`: Please refer to [Device](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#device). `capabilities`: An object that describes how to set capabilities. Please refer to [Capabilities](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#capabilities). --- ### closeSource Close the data source to free it to be used by other applications. **Syntax** ```typescript closeSource(device: Device): Promise; ``` **Parameters** `device`: Please refer to [Device](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#device). --- ### getProfile Gets custom scanner profile and returns it in a base64 string. **Syntax** ```typescript getProfile(device: Device): Promise; ``` **Parameters** `device`: Please refer to [Device](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#device). --- ### setProfile Set custom scanner profile to be used for scanning, the input is a base64 string. **Syntax** ```typescript setProfile(device: Device, dsDataString: string): Promise; ``` **Parameters** `device`: Please refer to [Device](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#device). `dsDataString`: The base64 string that contains custom scanner profile. --- **Event** ### onPostTransferAsync This event is triggered after each page has been scanned and transferred. **Syntax** ```typescript registerEvent("onPostTransferAsync", function (outputInfo: OutputInfo) {}); ``` **Arguments** `outputInfo`: Detailed information about the image that just got transferred. Please refer to [OutputInfo](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#outputinfo). **Example** ```javascript RemoteScanObject.registerEvent("onPostTransferAsync", function (outputInfo) { console.log("The image ID is " + outputInfo.imageId); }); ``` --- ## Buffer **Method** ### howManyImagesInBuffer Return how many images are held in the buffer. **Syntax** ```typescript readonly howManyImagesInBuffer: number; ``` --- ### currentImageIndexInBuffer Return the index of the current image in the buffer or set the image specified by index as the current image. **Syntax** ```typescript currentImageIndexInBuffer: number; ``` --- ### imageIDToIndex Return the index of an image specified by the imageId. **Syntax** ```typescript imageIDToIndex(imageId: number): number; ``` **Parameters** `imageId`: The imageId of the image. --- ### indexToImageID Return the imageId of an image specified by the index. **Syntax** ```typescript indexToImageID(index: number): number; ``` **Parameters** `index`: The index of the image. --- ### removeImages Remove the specified images. **Syntax** ```typescript removeImages(indices: number[]): Promise; ``` **Parameters** `indices`: The array of specified indices. --- **Event** ### onBufferChanged An enhanced callback triggered when a change occurs in the buffer. **Syntax** ```typescript registerEvent('onBufferChanged', function (bufferChangeInfo: BufferChangeInfo) {} ): boolean; ``` **Arguments** `bufferChangeInfo`: Details about the buffer change. Please refer to [BufferChangeInfo](https://www.dynamsoft.com/remote-scan/docs/api/Interfaces.md#bufferchangeinfo). **Usage notes** Action types include - `add`: New pages are added to the buffer. - `remove`: The existing pages are removed. - `modify`: The existing pages are modified. - `shift`: The existing pages are reordered. - `filter`: The existing pages are filtered by a tag. --- ## IO ### getImages Get the url/blob/base64 string of specified images. **Syntax** ```typescript getImages(indices: number[], type: Dynamsoft.DWT.EnumDWT_ImageType, imageFormatType: Dynamsoft.DWT.EnumDWT_ImageFormatType):Promise; ``` **Parameters** `indices`: The array of specified indices. `type`: Specify the image type. Please refer to [EnumDWT_ImageType](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_imagetype). `imageFormatType`: Specify image format to obtain. Please refer to [EnumDWT_ImageFormatType](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_imageformattype). --- ### httpUpload **Syntax** ```typescript httpUpload( URL: string, indices: number[], type: Dynamsoft.DWT.EnumDWT_ImageType, dataFormat: Dynamsoft.DWT.EnumDWT_UploadDataFormat, fileName: string, optionConfig?:{ responseType?: Dynamsoft.DWT.EnumDWT_ResponseType, formFields?:[{ name: string, value: Blob, fileName?: string }], headers?:[{ name: string, value: string }] } ): Promise; ``` **Parameters** `URL`: The server-side script to receive the post. For the sample code of Server Script, please refer to [Upload-Server-Script](https://www.dynamsoft.com/web-twain/docs/indepth/development/Server-script.md#how-to-process-uploaded-files). `indices`: Specify the image(s). `type`: The format of the file. Please refer to [EnumDWT_ImageType](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_imagetype). `dataFormat`: Whether to upload the file as binary or a base64 string. Please refer to [EnumDWT_UploadDataFormat](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_uploaddataformat). `fileName`: The file name to upload. `responseType`: Please refer to [EnumDWT_ResponseType](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_responsetype). --- ### saveImages **Syntax** ```typescript saveImages(fileName: string, indices: number[], type: Dynamsoft.DWT.EnumDWT_ImageType):Promise; ``` **Parameters** `fileName`: The file name to save. `indices`: The array of specified indices. `type`: Specify the image type. Please refer to [EnumDWT_ImageType](https://www.dynamsoft.com/remote-scan/docs/api/Dynamsoft_Enum.md#dynamsoftdwtenumdwt_imagetype). --- ### showProgressBar Return or set whether the progress bar is/should be displayed during encoding or decoding. **Syntax** ```typescript showProgressBar: Boolean; //default: true ``` --- ## Util ### registerEvent Specify an event listener for the specified built-in event. **Syntax** ```typescript registerEvent(name: string, callback: () => void): boolean; ``` **Parameters** `name`: Specify the event. `callback`: The event listener. --- ### unregisterEvent Remove an event listener from the specified built-in event. **Syntax** ```typescript unregisterEvent(name: string, callback: () => void): boolean; ``` **Parameters** `name`: Specify the event. `callback`: The event listener. --- ### dispose Dispose RemoteScanObject. **Syntax** ```typescript dispose(): boolean; ``` --- ### setLogLevel Set the log level for debugging. **Syntax** ```typescript setLogLevel(value: number):boolean; ``` **Parameters** `value`: 0 means turn off collecting log, 1 means turn on collecting log.