how to convert pdf to png file

[Packs]

how to convert pdf to png file .

[Thaddy]

Why would you want to do that?
If the display fits in a screen, simply save the screen (with the handle of the window that displays it) as a screenshot as png.
Otherwise it would be a png with a silly format in length. Which might not be accepted by all png capable applications.

So what are you trying to achieve?

[Packs]

I have pdf file which is having 28 mb file.

I want first page of the pdf and want to store inside database.

[loaded]

I use Ghostscript library for this kind of work. You can try it too.

[Packs]

You mean python libraries

[loaded]

You mean python libraries

No,

https://www.ghostscript.com/
You install this library on your computer, then you can split, merge, rotate, convert to text (limited) and convert images from lazarus via the command line.
If anyone knows another simpler and easier method, I would be happy if they shared it.

[Thaddy]

Correct. Good advice. But a first page would probably fit in a screenshot.

[Zvoni]

Correct. Good advice. But a first page would probably fit in a screenshot.

Not necessarily.
Take A4 for example: 29,7 cm high
For a 100% screenshot (no scaling involved) you'd need a Screen that high.

Scaling to fit a Screen not withstanding, but then there is "loss" involved

[rvk]

Correct. Good advice. But a first page would probably fit in a screenshot.

Can you enlighten us (preferable with some code) how you would make a screenshot from code without the need to open the PDF in a separate program or library?

The question is to create a thumbnail (probably much like the explorer.exe does in Windows at the right side when preview is on).

[Zvoni]

Alternative: XpdfReader's "pdftopng" commandline-tool
Fire it off via TProcess, passing the necessary options/arguments to it, and be done with it.

pdftopng -f 1 -l 1 mypdf.pdf mypng.png

Other options (dpi, color/gray/mono etc.) available

[rvk]

If it's for Windows, the optimal method would be to check if there is a preview handler for pdf (if Adobe reader is installed this could be PDFPrevHndlr.dll for example) and get a preview via that handler. Not sure if that's possible and how you could get it but that would be a neat way.

Of course there can also be other programs installed for viewing PDF. Getting the thumbnail from explorer.exe would also be an option (which in turn gets it from the default installed handler). But how to trigger the generation and retrieval of that thumbnail?

(And all this is assuming Windows  )

Something like this with IExtractImage.
https://stackoverflow.com/a/2916610/1037511

[Packs]

From free pascal by using code.

I have almost 40000 pdf

[MarkMLl]

Your OP ("how to convert pdf to png file .") was unclear: it could be read either that you were asking for help or that you were volunteering an example.

From free pascal by using code.

I have almost 40000 pdf

Are you sure that writing it from scratch is the best way to go? My experience (on Linux) is that pdftk (which pulls in stuff from Ghostscript etc.) is very much worth investigating: I did a fairly big document preparation job a few months ago and apart from a bit of semi-manual stuff to get a pagination overlay right it did everything I needed.

https://github.com/MarkMLl/paginate_pdfs

MarkMLl

[Packs]

Can anyone guide me how pdf file internally store objects.

I would like to understand internal architecture of pdf

[zeljko]

You can install PowerPDF from OPM and study code.