This tutorial shows how to create a new LEADDocument that loads and merges documents from a directory or to a stream in a Python application using the LEADTOOLS SDK.
Overview | |
---|---|
Summary | This tutorial covers how to merge documents using LEADDocument in a Python application |
Completion Time | 30 minutes |
Visual Studio Project | Download tutorial project (2 KB) |
Platform | Python Console Application |
IDE | Visual Studio 2022 |
Runtime Target | Python 3.10 or higher |
Development License | Download LEADTOOLS |
Try it in another language |
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Before working on the Merge Document with LEADDocument - Python tutorial, you need to be familiar with the basic steps of creating a project by reviewing the Add References and Set a License tutorial.
Start with a copy of the project created in the Add References and Set a License for Python topic.
If you do not have that project, follow the steps in the relevant tutorial to create it.
This tutorial requires the following .NET DLLs:
Leadtools.dll
Leadtools.Document.dll
Leadtools.Document.Writer.dll
Leadtools.Document.Converter.dll
Leadtools.Ocr.dll
For a complete list of which Codecs DLLs are required for specific formats, refer to File Format Support.
The License unlocks the features needed for the project. It must be set before any toolkit function is called. For details, including tutorials for different platforms, refer to Setting a Runtime License.
There are two types of runtime licenses:
With the project created, the references added, and the license set, coding can begin.
In the Solution Explorer, open Project-Name.py
and place the following references below the "Add references to LEADTOOLS" comment
# Add references to LEADTOOLS
from leadtools import LibraryLoader
LibraryLoader.add_reference("Leadtools")
from Leadtools import *
LibraryLoader.add_reference("Leadtools.Ocr")
from Leadtools.Ocr import *
LibraryLoader.add_reference("Leadtools.Document")
from Leadtools.Document import *
LibraryLoader.add_reference("Leadtools.Document.Writer")
from Leadtools.Document.Writer import *
LibraryLoader.add_reference("Leadtools.Document.Converter")
from Leadtools.Document.Converter import *
from System.IO import *
Add the below code to the main()
method to start the IOcrEngine
, merge PDF documents, and gather the stream from the created PDF document.
def main():
Support.set_license(os.path.join(DemosTools.get_root(), "C:/LEADTOOLS22/Support/Common/License"))
folder = r"C:\LEADTOOLS22\Resources\Images"
ocr_engine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD)
ocr_engine.Startup(None, None, None, r"C:\LEADTOOLS22\Bin\Common\OcrLEADRuntime")
ms = merge_pdf_files(folder, ocr_engine)
ms.Position = 0
File.WriteAllBytes(r"C:\LEADTOOLS22\Resources\Images\merged.pdf", ms.GetBuffer())
Add a new method called merge_pdf_files(dir, ocr_engine)
to return the stream containing the merged PDF document.
def merge_pdf_files(dir, ocr_engine):
document_writer = DocumentWriter()
# Get the current PDF options
pdf_options = document_writer.GetOptions(DocumentFormat.Pdf)
# Set our options
document_writer.SetOptions(DocumentFormat.Pdf, pdf_options)
pdf_options.ImageOverText = True
output_stream = MemoryStream()
create_options = CreateDocumentOptions()
virtual_document = DocumentFactory.Create(create_options)
virtual_document.AutoDisposeDocuments = True
virtual_document.Name = "Virtual"
files = Directory.GetFiles(dir, "*.pdf")
options = LoadDocumentOptions()
for file in files:
child_document = DocumentFactory.LoadFromFile(file, options)
virtual_document.Pages.AddRange(child_document.Pages)
# Convert virtual_document using the DocumentConverter to finalize the document and gather the stream
document_converter = DocumentConverter()
document_converter.SetOcrEngineInstance(ocr_engine, False)
document_converter.SetDocumentWriterInstance(document_writer)
job_data = DocumentConverterJobData()
job_data.Document = virtual_document
job_data.OutputDocumentStream = output_stream
job_data.DocumentFormat = DocumentFormat.Pdf
job = document_converter.Jobs.CreateJob(job_data)
document_converter.Jobs.RunJob(job)
if (job.Status == DocumentConverterJobStatus.Success):
print("Success!")
else:
print(f"{job.Status} Errors")
for error in job.Errors:
print(f"{error.Operation}, at {error.InputDocumentPageNumber}: {error.Error.Message}")
return output_stream
Note
Adding pages from child documents to a Virtual Document is not finalized. This means that the source pages from the child documents still only exist in the location they were originally loaded from. The Virtual Document only contains the information for where each page exists as well as other metadata about the page and file.
The Virtual Document can be displayed in a Document Viewer.
Or, the Virtual Document can be finalized and a new Document can be created by using the Document Converter as illustrated in this tutorial. This creates a legitimate document that contains copies of the source pages in its own document structure.
Run the project by pressing F5, or by selecting Debug -> Start Debugging.
If the steps were followed correctly, the application runs and creates a new virtual LEADDocument. The application then takes each PDF file from a given directory, and adds each PDF file to the virtual LEADDocument. Lastly, it "finalizes" the virtual document by sending it to the Document Converter.
This tutorial covered how to use the LEADDocument
and DocumentConverter
classes.