This article is meant exclusively for the Service mode of Dynamic Web TWAIN.
Dynamsoft Service is the core piece of Dynamic Web TWAIN when running in Service mode. It handles the communication between hardware (scanner, webcam, etc.) and browser, manages the image buffer, and coordinates data between different modules.
If Dynamsoft Service is not installed, you might receive the error ‘The Dynamic Web TWAIN module is not installed’ when accessing an application that uses Dynamic Web TWAIN.
The Dynamsoft Service uses
18625 ports for HTTP connection and
18626 ports for HTTPS connection.
These ports can be configured in the
DSConfiguration.ini file located in:
By default, there are three Dynamsoft Service processes running which use the same file
DynamsoftService.exe but initiated with different arguments.
The main process starts without any argument as follows:
Then there is a monitor process which is meant to monitor the main process and automatically start it in case it crashes. The monitor process starts like this:
C:\Windows\SysWOW64\Dynamsoft\DynamsoftServicex64\DynamsoftService.exe -asmonitor Global\Dynamsoft_1.5.0_352325843_stop_service_event Global\Dynamsoft_1.5.0_352325828_certcheck_event
The last always-running process is meant to support the SSL certificate specifically for the Firefox browser:
"-scan" "\\.\pipe\dynamsoftscan_15.0_70056_60" "0" "Global\ss352604281_61_70056" "0" "C:\Windows\SysWOW64\Dynamsoft\DynamsoftServicex64\dwt_trial_15.0.0.0625.dll"
Note: you may find another process named ‘Dynamsoft Scanning New Module’, which is a scan module. This process will start when you access an application integrated with Dynamic Web TWAIN, and will automatically stop when you close the application.
Service mode needs to be used if you wish to use a connected physical scanner. It is this Dynamsoft Service that handles all communication between the browser client and the scanner driver. As mentioned previously, Service mode is used by default if the user is on desktop.
- On Windows, the service runs under the Local System account
- On macOS, the service runs under the current user account
- On Linux, the service runs under the root account
This section is for your information only. Feel free to skip it if you are not particularly interested in what is included in the service directory.
There are multiple files and folders in the service directory. Taking Windows service (located at
C:\Windows\SysWOW64\Dynamsoft\DynamsoftServicex64_16) as an example, the content is as follows:
\cache\: Data cached on the disk. Check out Disk Caching.
\cert\: The certificates used for SSL connection. Check out How to change the certificates.
\dump\: Dump files in case the service crashes.
\log\: Log files for debugging purposes.
\upload\: Temporary location for image data to be uploaded by the file uploader.
DSConfiguration.ini: Service configuration file. Check out How to configure the service.
DWASManager_16000428.dll: The service manager. The name of the file may vary among different versions.
DynamsoftService.exe: The service.
DynamicSocket.dll: For socket connections.
service.ini: Define service name.
user_config.ini: User configuration file.
welcome.htm: The home page for the service (present when you visit http://127.0.0.1:18625)
These files are named with their version number. The following uses v16.1.1 as an example.
DynamicPdfR_11.0.0.0428.dll(for the PDF Rasterizer)
DynamicPdfRx64_11.0.0.0428.dll(for the PDF Rasterizer)
favicon.ico: The favicon.
legal.txt: Legal notice.
libcurl.dll: The file transfer library.
In this article: