When using the "From Image File(s)", depending on the program that generated the original image file, the PDF-XChange Editor may not recognize the format (True Color/Grayscale/Indexed/Monochrome), and the compression method set in advance in the Image Compression category of Options is not applied.
The following verification procedure attempts to set the "CCITT Group 4" compression method for the "Monochrome" format, but this is just an example to show you. It does not mean that the issue occurs only in this combination. Note that the compression method of the images is confirmed by the method introduced by Willy Van Nuffel in the following topic.
- https://forum.pdf-xchange.com/viewtopic.php?p=160759#p160759
- In the following verification, (A) a file converted to monochrome format in Microsoft Paint and (B) a file converted to monochrome format using "Export to Image(s)" in PDF-XChange Editor were each tested for "From Image File(s)" function. Confirm that (A) is compressed with "CCITT Group 4" without any problem, but (B) is compressed with "ZIP" unintentionally.
I have captured screen of each verification process for your reference, please see each attached video for details. The corresponding time code is also listed at the beginning of each verification procedure.
([MM:SS] "MM" stands for minutes and "SS" for seconds).
[00:00] - [00:04]
Prepare a full-color image file.
[00:05] - [00:19]
Open the file with Microsoft Paint and convert it to monochrome from its properties menu. Save the file as "MS_Paint.png".
[00:20] - [00:28]
To be sure, right-click the file in Explorer to open its properties and confirm that it has been converted to monochrome format.
[00:31] - [00:42]
Start the PDF-XChange Editor and open "From Image File(s)" function from the Convert tab, etc. Open Options in the lower left corner of the dialog and change the compression method of Monochrome to "CCITT Group 4" in the Image Compression category.
[00:43] - [00:48]
Click on "Add Files... to "MS_Paint.png" and import it.
[00:49] - [00:56]
Activate the edit function in the Home tab, right-click on the image and run "Recompress Image..." and you will see in the Current Image column that the compression method is CCITT Group 4. Note that since we are only checking the compression method, we do not execute "Recompress Image...".
[00:00] - [00:04]
Open a full-color image with the PDF-XChange Editor from the Explorer right-click menu.
[00:05] - [00:20]
From the Convert tab, perform an image conversion to output the image in monochrome PNG format. Here the file is named PDFXCE.png. In the video, the PDF-XChanger Editor is closed at this point, but this is not necessary.
[00:23] - [00:33]
Start the PDF-XChange Editor and open the "From Image File(s)" function from the Convert tab, etc. Open Options and change the compression method of Monochrome to "CCITT Group 4" in the Image Compression category.
[00:34] - [00:40]
Click on "Add Files... to "PDFXCE.png" and import it.
[00:41] - [00:48]
Activate the edit function in the Home tab, right-click on the image and run Recompress Image... The displayed contents in the Current Image column indicate that the compression method is ZIP.
I personally use XnView Classic as imaging software, and monochrome files output by this software are also not correctly recognized by PDF-XChange Editor. When you improve the program, it would be my great pleasure if you could recognize these files as well. I have included them in the attached file for your reference (XnViewClassic.png).
- https://www.xnview.com/en/xnview/
Thank you so much for your continued support.
Best regards,
rakunavi
- PDF-XChange Editor Plus Version:9.3 build 361.0
- XnView Classsic for Windows Version:2.51.0 (May 31 2022)
- OS Version: Windows 10 Home/Pro 21H2 Build 19044.1706
- PC Model: Lenovo IdeaPad C340-15IWL / HP ProDesk 600G1