How to Use SANE to Scan Documents on Windows

Nov 13, 2025

SANE is an API to access document scanners, which is mainly used in UNIX systems. It has several advantages over TWAIN (another document scanning API that is mainly for Windows):

TWAIN does not separate the user-interface from the driver of a device. This, unfortunately, makes it difficult, if not impossible, to provide network transparent access to image acquisition devices. SANE, on the other hand, can be used in a command-line environment without a problem.
SANE has built-in support for a wide range of scanners while we have to download and install separate drivers to use TWAIN.

There were attempts to make SANE run on Windows. But most of them still require a Linux host. With Windows Subsystem for Linux (WSL), this process has been made easier.

Read on to learn about how to do this.

Connect USB Devices to WSL

After installation of a Linux WSL distribution, set its version to 2 to use WSL 2.

PS C:\Users\admin> wsl -l  -v
  NAME            STATE           VERSION
  Debian          Running         1
PS C:\Users\admin> wsl --set-version Debian 2

Install USBIPD on Windows. You can find its installers on GitHub.

Use USBIPD to connect an USB device to WSL.

PS C:\Users\admin> usbipd list # list USB devices connected to the host
PS C:\Users\admin> usbipd bind --busid <busid> # share the device. You can find the bus id in the previous step
PS C:\Users\admin> usbipd attach --wsl --busid <busid> # attach the device to WSL

Run lsusb in Linux and you can find the USB device in the list.

$ lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 003: ID 04c5:132e Fujitsu, Ltd fi-7160

Use SANE to Scan Documents

Install SANE. Here, we are installing for Debian.
```
$ sudo apt install sane-utils
```

Use the scanimage command-line tool to list scanners and scan documents.

$ scanimage -L
device 'fujitsu:fi-7160:151477' is a FUJITSU fi-7160 scanner
$ scanimage -o scanned.png # save the document to an image

Scan Documents in the Browser

Next, we are going to use Dynamic Web TWAIN SDK to create a web page to scan documents in a browser on Windows and uses the SANE backend running in the WSL.

On WSL, install Dynamic Web TWAIN Service. You can find the installers on its npm package.
```
sudo dpkg -i DynamicWebTWAINServiceSetup.deb
```
The service will work as an HTTP server to communicate between web pages and scanners. You can check if it is installed by visiting http://127.0.0.1:18625.

You also need to start two processes when the system boots. Here is the command to launch them:
```
nohup "/opt/dynamsoft/Dynamic Web TWAIN Service 19/DynamsoftScanning" gtkproxy &
nohup "/opt/dynamsoft/Dynamic Web TWAIN Service 19/DynamsoftScanningMgr" &
```
You can create a service to start them by yourself.

Write a web page to scan documents and save as PDF with the following code:

<!DOCTYPE html>
<html>
<head>
  <title>Scan via SANE on Windows</title>
  <script src="https://cdn.jsdelivr.net/npm/dwt@latest/dist/dynamsoft.webtwain.min.js"></script>
</head>
<body>
  <button onclick="AcquireImage();">Scan</button>
  <button onclick="SaveAsPDF();">Save as PDF</button>
  <div id="dwtcontrolContainer"></div>
  <script type="text/javascript">
    Dynamsoft.DWT.Host = "local.dynamsoft.com";
    Dynamsoft.DWT.ResourcesPath = "https://cdn.jsdelivr.net/npm/dwt@latest/dist";
    //You need to set the service installer location here since the installer's size exceeds jsdelivr's limit. 
    //You'd better host the installers in your own environment.
    Dynamsoft.DWT.ServiceInstallerLocation = 'https://unpkg.com/dwt/dist/dist/';
    Dynamsoft.DWT.ProductKey = 'LICENSE-KEY';
    Dynamsoft.DWT.Containers = [{ ContainerId: 'dwtcontrolContainer', Width: 270, Height: 350 }];
    window.onload = function () {
      Dynamsoft.DWT.Load();
    };
    var DWTObject;
    Dynamsoft.DWT.RegisterEvent("OnWebTwainReady", function() {
      // dwtcontrolContainer is the id of the DIV to create the WebTwain instance in.
      DWTObject = Dynamsoft.DWT.GetWebTwain('dwtcontrolContainer');
    });
    function AcquireImage() {
      if (DWTObject) {
        DWTObject.SelectSourceAsync().then(function(){
          return DWTObject.AcquireImageAsync({
            PixelType: Dynamsoft.DWT.EnumDWT_PixelType.TWPT_RGB,
            Resolution: 200,
            IfCloseSourceAfterAcquire: true
          });
        }).catch(function (exp) {
          alert(exp.message);
        });
      }
    }

    function SaveAsPDF(){
      if (DWTObject) {
        DWTObject.ConvertToBlob(
          DWTObject.SelectAllImages(),
          Dynamsoft.DWT.EnumDWT_ImageType.IT_PDF,
          function (result, indices, type) {
            console.log(result.size);
            DownloadBlobAsFile(result, "scanned_document.pdf");
          },
          function (errorCode, errorString) {
            console.log(errorString);
          },
        );
      }
    }

    function DownloadBlobAsFile(blob, fileName) {
      var link = document.createElement('a');
      link.href = window.URL.createObjectURL(blob);
      link.download = fileName;
      link.click();
    }
  </script>
</body>
</html>

Now, we can use SANE to scan documents on Windows.

demo page

Source Code

https://github.com/tony-xlh/Dynamic-Web-TWAIN-samples/tree/main/Windows-SANE