Convert PDF to Searchable PDF

Overview

To make a searchable PDF by adding invisible text to an image based PDF such as a scanned document using OCR.

Set Transparent Text Layer

When outputting a searchable PDF, you can use the following option to control the hidden text layer:

• transparentText: Whether to output a transparent text layer.

Sample

Full code sample which shows how to use the ComPDF OCR module on scanned documents in multiple languages.

SearchablePdfOptions *options = [[SearchablePdfOptions alloc] init];
options.enableOCR = YES;
options.transparentText = YES;
options.languages = @[@(OCRLanguageChinese), @(OCRLanguageEnglish)];
[CPDFConversion startPDFToSearchablePDF:@"scan.pdf" password:@"" outputPath:@"path/output.pdf" options:options];