Dev Center
FAQ
SDK Download/Free Trial
How can I extend my free trial?
Where can I download an older version of the Dynamic Web TWAIN SDK?
Do you provide free trial versions of the Dynamic Web TWAIN SDK?
Can I run the scanning service on an ARM-based embedded device, such as Raspberry Pi?
Do you also provide an SDK download for Linux and Mac developers?
Is the free trial version fully functional?
Can I use the Dynamic Web TWAIN SDK to create a PWA application?
Capture/Image Source
What physical document scanners does the Dynamic Web TWAIN SDK support?
How to use TWACKER to check if your device is TWAIN Compliant?
How to test if your scanner supports ICA scanning on Mac OS?
How to test if your device is SANE compliant?
How to test if your camera is DirectShow compliant?
How to test if your camera is MediaDevices compliant?
Can I hide offline scanner devices from the select source list?
Can I hide webcam devices from the select source list?
What are the differences between TWAIN and WIA?
How can I set the last selected source as the default source for an end user?
How can I limit all users to use a specific scanner model?
Can the Dynamic Web TWAIN SDK automatically remove blank pages during the document scanning process?
Can the Dynamic Web TWAIN SDK automatically detect borders of the scanned document and crop it out?
Can the Dynamic Web TWAIN SDK detect whether papers exist on the flatbed?
How can I get a list of supported resolution/DPI values from the document scanner?
How can I use a custom capability of my scanner hardware when there is no direct API to set it?
Can I use built-in or USB webcam to capture document?
Can I import existing images or PDF documents using the Dynamic Web TWAIN SDK?
Can I download an image from a FTP or HTTP server using the Dynamic Web TWAIN SDK?
How can I trigger an automatic workflow right after document scanning or image importing?
Do you support capturing documents from mobile camera?
Do you support fingerprint or medical imaging devices?
What is the earliest iPhone model that your SDK supports?
Is the AcquireImage() method synchronous or asynchronous?
Why is my scanner not shown or not responding in the browser?
Download virtual scanner for testing
Image Viewer
Where is the image viewer object defined?
Can the size of the image viewer auto resize when the browser window size changes?
How can I create a thumbnail viewer to view images?
How can I change the background color of the image viewer?
How can I reorder images in the viewer?
How can I disable drag and drop images in the viewer?
How can I show multiple images at a time?
How can I show page number on each image?
How can I resize the view of image (e.g. zoom in/out on an image)?
What mouse click events does the viewer support?
How can I insert an image after a selected image in the viewer?
Can I protect sensitive information of an image from being seen?
Can I hide the Dynamsoft image viewer and use my own image viewer?
Can I print images from the viewer?
How to get the coordinates of the selected area on an image?
Image Editing
What image editing operations does the Dynamic Web TWAIN SDK support?
How can I show the default image editor tool?
How can I resize all images to meet a certain size standard (e.g. A4 size)
Can I add annotation to an image (e.g. add watermark or text)?
Can I change the resolution/DPI of an image in the viewer?
Can I convert a color image to grayscale or black & white?
Is there an undo functionality?
How can I remove only the selected images?
UI Customization
Is the UI of the Dynamic Web TWAIN SDK fully customizable? What cannot be customized?
How can I change the display language of all messages from English to another language?
How can I change/hide the spinner which shows during document scanning?
How can I change/hide the UI of the progress bar when importing or uploading images?
Can I customize UI elements of the built-in image editor?
Can I stop the scanner from showing its default popup when there is a paper jam?
Document Saving
What image and document formats can I save my documents as?
What type of HTTP servers do your support? Do you support other server types?
How can I enable HTTPS support?
How can I get the smallest size of documents in PDF, TIFF or JPEG format?
How can I send additional form fields with images to my server or database?
How can I automatically trigger actions when images arrive on my server side?
Can I upload documents to a different website domain?
How can I get a response string from my HTTP Server if the upload succeeds or fails?
Can I upload documents via a background service outside the web browser?
Can I insert newly scanned pages to an existing document?
How can I upload a JSON file to my server?
How can I save selected images instead of all images to my server or database?
How to use a blank page as a separator?
Security
Where does the Dynamic Web TWAIN SDK store images on end-user machines? Are they encrypted?
When are the locally cached images destroyed?
The license key is set in JavaScript. How can I protect it?
Does the Dynamic Web TWAIN SDK use any deprecated technologies like NPAPI or ActiveX?
How can I securely transfer scanned documents to my server?
Can I generate an encrypted file in PDF format?
Can I limit the size of documents to be uploaded to my server?
Is the Dynamic Web TWAIN SDK ISO 27001 compliant?
Is the Dynamic Web TWAIN SDK GDPR compliant?
Is the Dynamic Web TWAIN SDK HIPAA compliant?
How can I change the certificate of the Dynamsoft Service?
Addon
Do I need a separate license for each addon?
How can I load PDF/A files into the Dynamic Web TWAIN SDK?
Can I load specific page numbers of a PDF file into the viewer?
Do I need the PDF Rasterizer addon to convert scanned documents to PDF files?
How can I generate PDF/A files?
Does your Barcode Reader addon support patch code?
How can I separate my documents automatically by barcode?
Is there any way to speed up the barcode reading process?
What types of webcams does the Webcam Capture addon support
What’s the difference between your OCR Basic and OCR Pro SDK?
Does your OCR addon run on the client side or server side?
What is the difference between Camera.play and Camera.showVideo?
What is the difference between WebTwain.Addon.Camera and WebTwain.Addon.Webcam?
Project Deployment and End-user Installation
Can I install Dynamsoft Service silently?
How to uninstall Dynamsoft Service?
How to resolve if Dynamic Web TWAIN stops working on insecure websites in Chrome v94?
In which cases would I use local.dynamsoft.com instead of 127.0.0.1?
What resources of the SDK should be included in my web application?
How can I change the reference path to the Dynamsoft’s resources in my project?
Is there any component of the Dynamic Web TWAIN SDK that needs to be installed on end-user machines?
Are admin right required to install the end-user component?
Is there an easy way to deploy the end-user components to all users?
What does the Dynamsoft Service do on the end-user machine?
How do I upgrade my project to use the latest version of the Dynamic Web TWAIN SDK?
How do I upgrade the end-user installation for all end users once I upgrade my project?
How can I use Dynamic Web TWAIN in a Citrix environment?
How to resolve Dynamic Web TWAIN issue in Chrome 101?
Dynamic Web TWAIN – Content-Security-Policy violated
Dynamsoft Service installation and uninstallation issue
Scanner source is listed on XSane applicaton but not on my web application on Linux machines
How to run Dynamic Web TWAIN ActiveX in Microsoft Edge Internet Explorer (IE) mode
Error Troubleshooting
A connection with the server could not be established
Only 24-bit true color bmp and 8-bit gray-scaled images are supported for JPEG compression
XMLHttpRequest cannot load XXX
Source is connected to the maximum supported number of applications
Request header field dwt-md5 is not allowed by Access-Control-Allow-Headers in preflight response
The handle is in the wrong state for the requested operation
The connection with the server was terminated abnormally
Syntax error – Unexpected Token “<”
Uncaught ReferenceError - DVS is not defined
Error message - You have exceeded the number of OCR attempts allowed by the current license
Error message - The current product key does not support XXX, please contact the site administrator
Error message - The current product key is empty or invalid, please contact the site administrator
Error message – The current product key has expired on XXX, please contact the site administrator
Error Message - Failed to load resource: net::ERR_CERT_DATE_INVALID
Licensing and Purchase
What’s the difference between the Desktop Service Edition and WebAssembly Edition?
Is internet connectivity required to use all licenses?
Does the per-server license allow unlimited number of client devices and end users?
What license should I purchase if I am providing SaaS?
Will a client machine take an additional license seat if its operating system is reinstalled?
What if I reach the limit of the granted number of license seats?
Do you offer lifetime/perpetual licenses?
Do I need to purchase a license for my dev or testing environment?
I need to resell the SDK within my application to my customers. What options do you offer?
Are you flexible to discuss custom licensing models?
Do you have any local resellers from whom I can purchase a license of the Dynamic Web TWAIN SDK?
Do I get free upgrade if there is a newer version available?
Yes
No