I'm able to extract images from pdfs using the RenderListener class which seems to only support JPEG, any other type throws an error. Another approach I was considering is looping through the XObjects but I can't get the actual content from them. Is there any work around to extracting other image types from a PDF?
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We are converting HTML to PDF using a puppeteer and merging multiple PDFs into one, But the PDF generated by the puppeteer is too high.
We are thinking that the same embedded font is getting repeated for different pages, can we use the same font as a reference to PDF size will be decreased?
Font displayed in iText RUPS
I have a PDF file that contains an image where this image is successfully displayed. When I try to extract the image from the PDF file using itextsharp or pdfsharp libs I get bytes, then decode them successfully (because there is /Filter/FlateDecode there). But when I try to convert these bytes to an image using different libs the exception occured (it looks like the bytes are actually not an image). As far as I understand the problem is processing these bytes, but the image in the Pdf is not corrupted because it is shown there correctly. PDF is here.
The images are most likely stored in the PDF image format which is documented in the PDF specification.
It is rather simple to convert them to the Windows BMP format. But still you must convert them and add headers with the specific information from the image attributes from the PDF file.
In PDF a new image line is byte-aligned, in Windows BMP it is DWORD-aligned.
Don't forget to extract the colour table if there is one.
The use of xfa inside pdf isn’t only for creating forms
Short : I need valid test cases for a new xfa ᴘᴅꜰ reader, but couldn’t found anyone nor I could find how to use ghostscript in order to create such test cases in batch.
The point is I don’t know how to build the extra information ghostscript should handle without an hex editor.
Ghostscript doesn't handle XFA at all, neither on input nor in output, you cannot use Ghostscript to create XFA files.
Nor does Ghostscript (currently) create PDF files which solely consist of an image. Even if it did, these wouldn't be PNG or TIFF images, as those file formats are not directly supported by PDF. The next release of Ghostscript will contain devices which produce PDF files where the content is a rendered bitmap image created from the input. But they won't be either PNG or TIFF file format.
Note that XFA has been removed from the PDF 2.0 specification (hardly surprising as its XML not PDF format).
I'm working with PDFClown and I'm trying to extract images from a pdf file. I use the example code provided by the source code that can be found at http://pdfclown.org.
ImageExtractionSample.java.
The problem is the images are negative and flipped horizontally. Does anyone know how to resolve this problem?
Check with other PDF files to see if other PDF files are also giving the rotated or flipped images. ImageExtractionSample.java is not checking rotation or matrix defined transformations for the image object but just writes the content to a file as is (so it will work for JPG images but not for CCIT encoded images for example).
So there are things to consider when you extract image from PDF:
image can be rotated using the attached transformation matrix (CTM);
image can be rotated/transformed as part of the form which is transformed;
image can be placed without transformation on a page but the page itself is rotated;
image may contain the overlaid Mask on top of it (and the Mask can be rotated and transformed);
JPG image is stored pretty much as is but there are other formats supported by PDF like CCIT compression, LZW compressed images etc;
But the general suggestion is that when you extract JPG image from PDF using PDFClown you should just flip and rotate extracted images like suggested on the SourceForge project discussion page.
if you could point to the particular PDF sample file then it would be easier to suggest the solution.
If you're on Windows then you may use this free PDF Multitool utility to compare non-transformed and transformed images from PDF using "Extract raw images (without transformation)" option in images extraction dialog.
Disclaimer: I work for ByteScout, the PDF Multitool utility is free for both commercial and non-commercial purposes.
I have a few books that I absolutely MUST be reading; they are a set of calculus textbooks as PDF files. The problem is that the graphs and images in these pdf file are all png, which is apparently not supported by my kindle. Is there anyway I can convert these images as a batch into jpeg or any other format inside the pdf file. I have tried everything from converting the pdf to other formats (equation formatting didn't let it work), to extracting the images from the pdf file and getting them converted. I just really need to know if there is any program I can use to help me or if maybe, there is a way I could 'open' the pdf container, and switch out the png images for the jpeg images and replace the png file extensions with jpg. Any help would be greatly appreciated.
The books are:
http://tutorial.math.lamar.edu/pdf/CalcI/CalcI_Complete.pdf
http://tutorial.math.lamar.edu/pdf/CalcII/CalcII_Complete.pdf