Create image file but retain pdf transparency

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   Hello, I have just found this amazing sdk but I am having some difficulties with creating image files from PDF.
I can create a pdf and load an image to it with transparency (basic outline of code below)  
Call objPDF.LoadFromFile(strPDFFolder & "\" & strPDFFile, "")
dblImageID = objPDF.AddImageFromFile(strWMFolder & "\" & strWMFile, 0)
objPDF.NormalizePage (0)
objPDF.SetOrigin (1)
dblContentStream = objPDF.NewContentStream
objPDF.SelectContentStream (dblContentStream)
objPDF.SaveState
objPDF.SetTransparency (dblTransparency)
objPDF.SelectImage (dblImageID)
Call objPDF.DrawImage(0, 0, objPDF.PageWidth, objPDF.PageHeight)
objPDF.LoadState
Call objPDF.MoveContentStream(dblContentStream, IIf(blnLayerZero = True, 0, objPDF.ContentStreamCount + 1))
objPDF.SaveToFile (strPDFFolderNew & "\" & strPDFFileNew)

This applies an image to the PDF and sets it transparency perfectly, but when generating the image file the actual image I applied to the PDF is the only thing I see in the image file, so the transparency setting I applied is being ignored and set at 100 (assuming). 

Is there any way to create the image file that retains the transparency we apply to the PDF?

Thanks,

Benjamin

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bbenc Members Profile Find Members Posts Beginner Joined: 20 Dec 19 Location: Australia Status: Offline Points: 8	Post Options Post Reply Quote bbenc Report Post Thanks(0) Quote Reply Topic: Create image file but retain pdf transparency Posted: 20 Dec 19 at 6:40AM
	Hello, I have just found this amazing sdk but I am having some difficulties with creating image files from PDF. I can create a pdf and load an image to it with transparency (basic outline of code below) Call objPDF.LoadFromFile(strPDFFolder & "\" & strPDFFile, "") dblImageID = objPDF.AddImageFromFile(strWMFolder & "\" & strWMFile, 0) objPDF.NormalizePage (0) objPDF.SetOrigin (1) dblContentStream = objPDF.NewContentStream objPDF.SelectContentStream (dblContentStream) objPDF.SaveState objPDF.SetTransparency (dblTransparency) objPDF.SelectImage (dblImageID) Call objPDF.DrawImage(0, 0, objPDF.PageWidth, objPDF.PageHeight) objPDF.LoadState Call objPDF.MoveContentStream(dblContentStream, IIf(blnLayerZero = True, 0, objPDF.ContentStreamCount + 1)) objPDF.SaveToFile (strPDFFolderNew & "\" & strPDFFileNew) This applies an image to the PDF and sets it transparency perfectly, but when generating the image file the actual image I applied to the PDF is the only thing I see in the image file, so the transparency setting I applied is being ignored and set at 100 (assuming). Is there any way to create the image file that retains the transparency we apply to the PDF? Thanks, Benjamin

bbenc Members Profile Find Members Posts Beginner Joined: 20 Dec 19 Location: Australia Status: Offline Points: 8	Post Options Post Reply Quote bbenc Report Post Thanks(0) Quote Reply Posted: 20 Dec 19 at 6:43AM
	oh, sorry, forgot to add. I am using the following code to generate the image file: Call objPDF.RenderDocumentToFile(dblDPI, 1, dblPages, 0, strPDFFolder & "\" & strImageFile & "." & strImageFileExt) Ive also tried the DARenderToPage with the same results. I am using version 17 activeX or DLL. Edited by bbenc - 20 Dec 19 at 7:44AM

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3524	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 20 Dec 19 at 11:03AM
	Hi Benjamin, did you do the rendering right after the save? Try it after a new load... Cheers and welcome here, Ingo
	Cheers, Ingo

bbenc Members Profile Find Members Posts Beginner Joined: 20 Dec 19 Location: Australia Status: Offline Points: 8	Post Options Post Reply Quote bbenc Report Post Thanks(0) Quote Reply Posted: 20 Dec 19 at 2:40PM
	Thankyou for the reply Ingo, but unfortunately that didn't work for me (as that's what I was doing), but thought I might try the render immediately (ie: before the save to pdf) but unfortunately that didn't work either. My code is written modularly, so the first module combines the images, saves them as a pdf, and releases the object. The next module does a fresh load of the saved file and renders to image. I was thinking the layers weren't supported by jpg, so I tried gif/tif/png...all 10 supported file formats and still get the same result...The semi transparent image becomes 0% transparent (fully displayed) in the image file. The test image file I am using (as the transparent layer) has a white background. Maybe I could try and overlay an image without a background layer. I'm really not sure what else to try.

bbenc Members Profile Find Members Posts Beginner Joined: 20 Dec 19 Location: Australia Status: Offline Points: 8	Post Options Post Reply Quote bbenc Report Post Thanks(0) Quote Reply Posted: 20 Dec 19 at 2:50PM
	Just tried a "background-less" image, but when its put into the pdf, it masks the "missing" background with white. The render to image retains that white background.

bbenc Members Profile Find Members Posts Beginner Joined: 20 Dec 19 Location: Australia Status: Offline Points: 8	Post Options Post Reply Quote bbenc Report Post Thanks(0) Quote Reply Posted: 20 Dec 19 at 3:00PM
	Ok, so I just tried to apply transparent text to a pdf and then render it to an image and it worked perfectly, so not sure why the transparent image is not co-operating.