Why can't extract text from pdf?

[daitranthanhhoa]

I install Spire.pdf 7.3.1 from nuget:
This my code:

Code: Select all

 Spire.Pdf.PdfDocument doc = new Spire.Pdf.PdfDocument();
            doc.LoadFromFile("test1.pdf");
            PdfPageBase page = doc.Pages[0];
            Spire.Pdf.Exporting.Text. SimpleTextExtractionStrategy sta = new Spire.Pdf.Exporting.Text.SimpleTextExtractionStrategy();
            string text = page.ExtractText(sta);

Occur Exception: "Object reference not set to an instance of an object."

Code: Select all

 at sprᷥ.ᜐ(sprᥲ A_0)
   at sprᷥ.ᜈ()
   at sprᷧ.ᜀ(sprᥳ A_0, sprᝮ A_1)
   at sprᷧ.ᜀ()
   at sprᷧ..ctor(PdfPageBase A_0, sprᷡ A_1, Boolean A_2)
   at sprᷠ.ᜁ(PdfPageBase A_0)
   at sprᣛ.ᜀ(PdfPageBase A_0, Boolean A_1, RectangleF A_2)
   at Spire.Pdf.PdfPageBase.ExtractText(RectangleF rectangleF, SimpleTextExtractionStrategy sim)
   at Spire.Pdf.PdfPageBase.ExtractText(SimpleTextExtractionStrategy strategy)

Data test: https://drive.google.com/file/d/1C0eI-l8un79yYf-SNtBteVobKjhSv-1O/view?usp=sharing

[amy.zhao]

Hello,

Thanks for your inquiry.
I have reproduced your issue and logged it in our bug tracking system with the ticket SPIREPDF-4097.
Sorry for the inconvenience caused. I will inform you once it is solved.

Sincerely,
Amy
E-iceblue support team

[daitranthanhhoa]

[amy.zhao]

Hello,

Our developer just fixed SPIREPDF-4097 issue, next, we will build a new version to test the fix. Once new version is released, I will inform you.

Sincerely,
Amy
E-iceblue support team

[daitranthanhhoa]

[amy.zhao]

Hi,

It will take a while for the official version to be released as it contains a number of fixes and feature updates that require more time for verification. But I can provide you with a temporary version soon. Do you need it?

Sincerely,
Amy
E-iceblue support team

[daitranthanhhoa]

Yes, Please send.
Thank you.

[amy.zhao]

Hi,

Please download the temporary version for testing first . When the official version is released, we will inform you.

Sincerely,
Amy
E-iceblue support team

[daitranthanhhoa]

Hi some case can't extract text:
Data test: https://drive.google.com/file/d/1a414Qd ... sp=sharing

[Brian.Li]

Hello,

Thanks for your feedback.
Regarding the new file you provided, after analyzing, I found that the text property of your PDF file is “path” but not “text”, you could use a PDF editor tool like Foxit PDF Editor to verify this. Thus, no text could be extracted. Even using Adobe to extract, there is a same result. Hope you can understand.
If there are any other questions, please feel free to contact us.

Sincerely,
Brian
E-iceblue support team

[daitranthanhhoa]

I using Acrobat , It can edit text.

[Brian.Li]

Hello,

Thanks for your reply.
When opening your PDF under the view mode (not edit mode) in Adobe, you will find that you cannot select any content. Meanwhile, if you press “Ctrl+F” to search the text, you will get the message “This is a scanned PDF and cannot be searched”.

FindTextInAdobe.png

The mechanism of Adobe's edit mode and view mode is different. For the edit mode, Adobe is supposed to use OCR technology to convert the scanned page into editable text and images, so you can edit the text. But in edit mode, if you copy the content directly and then paste it to a TXT file, you will get garbled characters (as shown below). This also indicates that the actual content of your PDF text cannot be extracted. You can verify it on your side.

copyContent.png

Sincerely,
Brian
E-iceblue support team

[daitranthanhhoa]

OK, Thank you.

[Brian.Li]

You are welcome.
If there are any other questions related to our products, just feel free to contact us.

Sincerely,
Brian
E-iceblue support team

[Marcia.Zhou]

Hello,

Thanks for your patience!

Glad to inform you that we just released Spire.PDF Pack(Hot Fix) Version:7.4.5 which fixes the issue SPIREPDF-4097.

Please download the fix version from the following links to test.
Website link:
https://www.e-iceblue.com/Download/download-pdf-for-net-now.html
Nuget link:
https://www.nuget.org/packages/Spire.PDF.NETCore/7.4.5
https://www.nuget.org/packages/Spire.PDF/7.4.5

Sincerely,
Marcia
E-iceblue support team