PDF Compression Help

[chad_omnant]

I am trialing your software in an attempt to compress a PDF in file size. I know the file can be compressed because if use various web tools - these reduce them by about 75% (pdf2go, etc). I am using the example code from the following website but it is not resulting in any smaller of PDF. What am I doing wrong?

The example code can be found here - it is too big to upload as part of this ticket...

omnant [dot] com/PdfCompression.Iceblue.zip

[Elena.Zhang]

Hello,

Thanks for your inquiry.
I noticed that your PDF file mainly contains images, you can use the “TryCompressImage”method to directly compress images in PDF files, below is the corresponding code for your reference. If there are any questions, please feel free to write back.

Code: Select all

public static void CompressContent(PdfDocument doc)
        {
            //Disable the incremental update
            doc.FileInfo.IncrementalUpdate = false;

            //Set the compression level to best
            doc.CompressionLevel = PdfCompressionLevel.Best;
        }

        public static void CompressImage(PdfDocument doc)
        {
            //Disable the incremental update
            doc.FileInfo.IncrementalUpdate = false;

            //Traverse all pages
            foreach (PdfPageBase page in doc.Pages)
            {
                if (page != null)
                {
                    if (page.ImagesInfo != null)
                    {
                        foreach (PdfImageInfo info in page.ImagesInfo)
                        {
                            page.TryCompressImage(info.Index);
                        }
                    }
                }
            }
        }

        public static void Main(string[] args)
        {
           
            PdfDocument pdf = new PdfDocument();
            pdf.LoadFromFile("Drawing.pdf");
            //Compress the content in document
            CompressContent(pdf);

            //Compress the images in document
            CompressImage(pdf);

            //Save the document
            pdf.SaveToFile("CompressDocument_result.pdf");
        }


Sincerely,
Elena
E-iceblue support team

[chad_omnant]

Thanks for the response. I was able to incorporate your code into my example. However, it only took the file from 14.5 MB to 11.5 MB. Is this the best expectation I should have with your toolkit?

[Elena.Zhang]

Hello,

Thanks for your feedback.
Since your document contains a lot of images, I am worried that it may be difficult to compress your file even smaller using our Spire.PDF. However, I have posted this issue to our Dev team and they will investigate whether the file size can be further optimized. If there is any good news, we will inform you.

Sincerely,
Elena
E-iceblue support team

[chad_omnant]

Checking in to see if there was any update on this issue.

[Elena.Zhang]

Hello,

Thanks for your following up.
Sorry there is no significant progress yet, please spare us more time. I will let you know if there any update. Thanks for your understanding.

Sincerely,
Elena
E-iceblue support team