Как получить изображения с различным горизонтальным и вертикальным разрешением от TWAIN/SANE сканера?

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Получение изображений с разным горизонтальным и вертикальным разрешением от TWAIN сканера

Вот JavaScript код, который демонстрирует, как получить изображения с различным горизонтальным и вертикальным разрешением от TWAIN сканера:

JavaScript

// acquire images with different horizontal and vertical resolution from TWAIN scanner
__acquireImageWithDifferentHorizontalAndVerticalResolutionsFromTwainScanner();



/**
 * Acquires images with different horizontal and vertical resolution from TWAIN scanner.
 */
function __acquireImageWithDifferentHorizontalAndVerticalResolutionsFromTwainScanner() {
    // register the evaluation version of VintaSoft Web TWAIN service
    // please read how to get evaluation license in documentation: https://www.vintasoft.com/docs/vstwain-dotnet-web/Licensing-Twain_Web-Evaluation.html
    Vintasoft.Twain.WebTwainGlobalSettingsJS.register('REG_USER', 'REG_URL', 'REG_CODE', 'EXPIRATION_DATE');

    // URL to the VintaSoft Web TWAIN service
    var serviceUrl = 'https://localhost:25329/api/VintasoftTwainApi';
    // a Web API controller that allows to work with TWAIN and SANE devices
    var twainService = new Vintasoft.Shared.WebServiceControllerJS(serviceUrl);

    // TWAIN device manager
    var deviceManager = new Vintasoft.Twain.WebTwainDeviceManagerJS(twainService);

    // the default settings of device manager
    var deviceManagerInitSetting = new Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS();

    var device = null;
    try {
        // open device manager
        deviceManager.open(deviceManagerInitSetting);

        // get the default TWAIN device
        device = deviceManager.get_DefaultDevice();

        // open device without UI
        device.open(false);

        // specify that acquired image must have 300 dpi horizontal resolution
        device.set_XResolution(300);
        // specify that acquired image must have 200 dpi vertical resolution
        device.set_XResolution(200);

        var acquireModalState;
        do {
            // do one step of modal image acquisition process
            var acquireModalResult = device.acquireModalSync();
            // get state of image acquisition
            acquireModalState = acquireModalResult.get_AcquireModalState().valueOf();

            switch (acquireModalState) {
                case 2:   // image is acquired
                    // get acquired image
                    var acquiredImage = acquireModalResult.get_AcquiredImage();
                    // get image as Base64 string
                    var bitmapAsBase64String = acquiredImage.getAsBase64String();
                    // update image preview
                    var previewImageElement = document.getElementById('previewImage');
                    previewImageElement.src = bitmapAsBase64String;
                    break;
                case 4:   // image scan is failed
                    alert(acquireModalResult.get_ErrorMessage());
                    break;
                case 9:   // image scan is finished
                    break;
            }
        }
        while (acquireModalState !== 0);
    }
    catch (ex) {
        alert(ex);
    }
    finally {
        if (device != null) {
            // close the device
            device.close();
        }
        // close the device manager
        deviceManager.close();
    }
}

Вот TypeScript код, который демонстрирует, как получить изображения с различным горизонтальным и вертикальным разрешением от TWAIN сканера:

TYPESCRIPT

import { Component } from '@angular/core';

@Component({
  selector: 'twain-scanning-demo',
  templateUrl: './twain-scanning-demo.component.html'
})
export class TwainScanningDemoComponent {

  ngOnInit() {
    // acquire images with different horizontal and vertical resolution from TWAIN scanner
    this.__acquireImageWithDifferentHorizontalAndVerticalResolutionsFromTwainScanner();
  }


  /**
   * Acquires images with different horizontal and vertical resolution from TWAIN scanner.
   */
  __acquireImageWithDifferentHorizontalAndVerticalResolutionsFromTwainScanner() {
    // register the evaluation version of VintaSoft Web TWAIN service
    // please read how to get evaluation license in documentation: https://www.vintasoft.com/docs/vstwain-dotnet-web/Licensing-Twain_Web-Evaluation.html
    Vintasoft.Twain.WebTwainGlobalSettingsJS.register('REG_USER', 'REG_URL', 'REG_CODE', 'EXPIRATION_DATE');

    // URL to the VintaSoft Web TWAIN service
    let serviceUrl: string = 'https://localhost:25329/api/VintasoftTwainApi';
    // a Web API controller that allows to work with TWAIN and SANE devices
    let twainService: Vintasoft.Shared.WebServiceControllerJS = new Vintasoft.Shared.WebServiceControllerJS(serviceUrl);

    // TWAIN device manager
    let deviceManager: Vintasoft.Twain.WebTwainDeviceManagerJS = new Vintasoft.Twain.WebTwainDeviceManagerJS(twainService);

    // the default settings of device manager
    let deviceManagerInitSetting: Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS = new Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS();

    try {
      // open device manager
      deviceManager.open(deviceManagerInitSetting);
    }
    catch (ex) {
      alert(ex);
      return;
    }

    let device: Vintasoft.Twain.WebTwainDeviceJS = null;
    try {
      // get the default TWAIN device
      device = deviceManager.get_DefaultDevice();

      // open device without UI
      device.open(false);

      // specify that acquired image must have 300 dpi horizontal resolution
      device.set_XResolution(300);
      // specify that acquired image must have 200 dpi vertical resolution
      device.set_XResolution(200);

      let acquireModalState: number;
      do {
        // do one step of modal image acquisition process
        let acquireModalResult: Vintasoft.Twain.WebTwainDeviceAcquireModalResultJS = device.acquireModalSync();
        // get state of image acquisition
        acquireModalState = acquireModalResult.get_AcquireModalState().valueOf() as number;

        switch (acquireModalState) {
          case 2:   // image is acquired
            // get acquired image
            let acquiredImage: Vintasoft.Twain.WebAcquiredImageJS = acquireModalResult.get_AcquiredImage();
            // get image as Base64 string
            let bitmapAsBase64String: string = acquiredImage.getAsBase64String();
            // update image preview
            let previewImageElement: HTMLImageElement = document.getElementById('previewImage') as HTMLImageElement;
            previewImageElement.src = bitmapAsBase64String;
            break;
          case 4:   // image scan is failed
            alert(acquireModalResult.get_ErrorMessage());
            break;
          case 9:   // image scan is finished
            break;
        }
      }
      while (acquireModalState !== 0);
    }
    catch (ex) {
      alert(ex);
    }
    finally {
      if (device != null) {
        // close the device
        device.close();
      }
      // close the device manager
      deviceManager.close();
    }
  }

}

Получение изображений с разным горизонтальным и вертикальным разрешением от SANE сканера

SANE API не определяет стандартные опции, которые позволяют устанавливать различные разрешения по горизонтали и вертикали для сканированных изображений. Пожалуйста посмотрите список поддерживаемых опций вашего SANE устройства.

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