Update PDF/A documentation to clarify licensing requirements and rasterization process

Author: lyzhang0113

_articles/faq/generate-pdf-files.md

@@ -7,7 +7,7 @@ keywords: Dynamic Web TWAIN, Addon, separate, license
 breadcrumbText: How can I generate PDF/A files?
 description: How can I generate PDF/A files?
 date: 2021-12-01 01:09:41 +0800
-last_modified: 2025-12-10 15:15:15 +0800
+last_modified: 2025-12-10 16:43:15 +0800
 ---
 
 # Addon
@@ -42,6 +42,15 @@ Although both variants ensure that documents can be reliably displayed in the fu
 For most use cases, we recommend using **`pdf/a-2b`**.
 It offers better compression support, fewer limitations, and higher compatibility with modern PDFs while still meeting archival requirements.
 
+### Licensing Requirements
+Dynamic Web TWAIN does not require any add-on license to **export** or generate PDF or PDF/A files. However, PDF-Rasterizer Addon would be required when **loading** a PDF/PDF-A file that contains **text or vector graphics**.
+
+You can programmatically check whether a file needs rasterization using [`IsRasterizationRequired()`](/_articles/info/api/Addon_PDF.html#israsterizationrequired):
+
+```javascript
+DWTObject.Addon.PDF.IsRasterizationRequired(path); // returns true or false
+```
+
 ### Behavior and Defaults
 
 - If you do not set `pdfaVersion`, the export uses standard PDF format (non-PDF/A).

_articles/faq/load-pdf-files.md

@@ -7,22 +7,38 @@ keywords: Dynamic Web TWAIN, Addon, load pdf/a
 breadcrumbText: How can I load PDF/A files into the Dynamic Web TWAIN SDK?
 description: How can I load PDF/A files into the Dynamic Web TWAIN SDK?
 date: 2021-12-01 01:09:41 +0800
-last_modified: 2022-10-21 14:05:54 +0800
+last_modified: 2025-12-10 15:53:54 +0800
 ---
 
 # Addon
 
 ## How can I load PDF/A files into the Dynamic Web TWAIN SDK?
 
-You can use the PDF Rasterizer add-on which supports reading PDF/A images.
+Dynamic Web TWAIN can load PDF/A files, but whether the PDF Rasterizer add-on is required depends on the content of the PDF/A file:
 
-If the PDF Rasterizer add-on is used, the file will automatically be rasterized when it's loaded to the viewer.
+- If the PDF/A contains text or vector graphics, it must be rasterized, and therefore requires the PDF Rasterizer add-on.
+- If the PDF/A contains only raster images, it can be loaded without the PDF Rasterizer.
 
-### When is PDF Rasterizer effective?
+You can programmatically check whether a file needs rasterization using [`IsRasterizationRequired()`](/_articles/info/api/Addon_PDF.html#israsterizationrequired):
 
-Once `PDFR` has been configured, it will automatically detect if a file needs to be rasterized and if so, it will convert it to an image(s) with the set resolution(if no resolution is set, the default is 200). This happens when you call any of the following methods
+```javascript
+DWTObject.Addon.PDF.IsRasterizationRequired(path); // returns true or false
+```
 
-> `PDFR` also works when you drag and drop the file onto the viewer to load it
+When enabled, the add-on automatically rasterizes PDF/A documents into images when they are loaded into the viewer.
+
+> [!NOTE]
+> **Looking for information about generating PDF/A files?**
+> Starting from Dynamic Web TWAIN 19.3, PDF/A creation is supported.
+> See: [How can I generate PDF/A files?](/_articles/faq/generate-pdf-files.md)
+
+
+### When is PDF Rasterizer used?
+
+Once the PDF Rasterizer (`PDFR`) is configured, it automatically rasterizes the file *only when needed*.
+If rasterization is required, the PDF is converted into one or more images at the specified resolution (default **200 DPI**).
+
+Rasterization may occur when using any of the following APIs (including drag-and-drop):
 
 - [ `LoadImage()` ](/_articles/info/api/WebTwain_IO.md#loadimage)
 - [ `LoadImageEx()` ](/_articles/info/api/WebTwain_IO.md#loadimageex)
@@ -35,4 +51,8 @@ Once `PDFR` has been configured, it will automatically detect if a file needs to
 - [ `HTTPDownloadThroughPost()` ](/_articles/info/api/WebTwain_IO.md#httpdownloadthroughpost)
 - [ `HTTPDownloadDirectly()` ](/_articles/info/api/WebTwain_IO.md#httpdownloaddirectly)
 
-Dynamic Web TWAIN does not support the generation of PDF/A files.
+### Important Change in v19.3
+Previous versions of Dynamic Web TWAIN did **not** support exporting PDF/A files.
+As of **19.3**, you can now:
+- Load PDF/A files (with or without the PDF Rasterizer, depending on content), and
+- Generate PDF/A files using the PDF Add-on.