
I would recommend you to use LibPdf, for PDF to Image conversion. This library will convert PDF file to image with PNG and BMP as supported image format.
I hope the below example will encourage you to give converting PDF to image a shot.
using (FileStream file = File.OpenRead(@”..\path\to\pdf\file.pdf”)) // in file
{
var bytes = new byte[file.Length];
file.Read(bytes, 0, bytes.Length);
using (var pdf = new LibPdf(bytes))
{
byte[] pngBytes = pdf.GetImage(0,ImageType.PNG); // image type
using (var outFile = File.Create(@”..\path\to\pdf\file.png”)) // out file
{
outFile.Write(pngBytes, 0, pngBytes.Length);
}
}
}
Code Credit: stackoverflow
If you are looking to convert PDF to an image but in an easy manner and not much interested in coding then try ImageMagick, it will simply not do your job but also provide few .NET Bindings
This is very simple.
convert file.pdf imagefile.png
Here is the function, which will convert the PDF into images. Add the following lines of code.
-(void)splitPDF:(NSURL *)sourcePDFUrl withOutputName:(NSString *)outputBaseName intoDirectory:(NSString *)directory
{
CGPDFDocumentRef SourcePDFDocument = CGPDFDocumentCreateWithURL((__bridge CFURLRef)sourcePDFUrl);
size_t numberOfPages = CGPDFDocumentGetNumberOfPages(SourcePDFDocument);
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePathAndDirectory = [documentsDirectory stringByAppendingPathComponent:directory];
NSError *error;
if (![[NSFileManager defaultManager] createDirectoryAtPath:filePathAndDirectory
withIntermediateDirectories:NO
attributes:nil
error:&error])
{
NSLog(@”Create directory error: %@”, error);
return;
}
for(int currentPage = 1; currentPage <= numberOfPages; currentPage ++ )
{
CGPDFPageRef SourcePDFPage = CGPDFDocumentGetPage(SourcePDFDocument, currentPage);
// CoreGraphics: MUST retain the Page-Refernce manually
CGPDFPageRetain(SourcePDFPage);
NSString *relativeOutputFilePath = [NSString stringWithFormat:@”%@/%@%d.png”, directory, outputBaseName, currentPage];
NSString *ImageFileName = [documentsDirectory stringByAppendingPathComponent:relativeOutputFilePath];
CGRect sourceRect = CGPDFPageGetBoxRect(SourcePDFPage, kCGPDFMediaBox);
UIGraphicsBeginPDFContextToFile(ImageFileName, sourceRect, nil);
UIGraphicsBeginImageContext(CGSizeMake(sourceRect.size.width,sourceRect.size.height));
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(currentContext, 0.0, sourceRect.size.height); //596,842 //640×960,
CGContextScaleCTM(currentContext, 1.0, -1.0);
CGContextDrawPDFPage (currentContext, SourcePDFPage); // draws the page in the graphics context
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSString *imagePath = [documentsDirectory stringByAppendingPathComponent: relativeOutputFilePath];
[UIImagePNGRepresentation(image) writeToFile: imagePath atomically:YES];
}
}
Here, is the description of line of codes those are mentioned above.
CGPDFDocumentRef SourcePDFDocument = CGPDFDocumentCreateWithURL((__bridge CFURLRef)sourcePDFUrl);
size_t numberOfPages = CGPDFDocumentGetNumberOfPages(SourcePDFDocument);
Firstly it will create a document reference and then through that reference it will ake out the number of pages.
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePathAndDirectory = [documentsDirectory stringByAppendingPathComponent:directory];
NSError *error;
if (![[NSFileManager defaultManager] createDirectoryAtPath:filePathAndDirectory
withIntermediateDirectories:NO
attributes:nil
error:&error])
{
NSLog(@”Create directory error: %@”, error);
return;
}
Then it will check either the PDF, which we are converting into images, exists or not. If it does not exist or there is any error it returns from the same part.
for(int currentPage = 1; currentPage <= numberOfPages; currentPage ++ )
In this it will start the loop and start fetching the each page of the PDF
CGPDFPageRef SourcePDFPage = CGPDFDocumentGetPage(SourcePDFDocument, currentPage);
// CoreGraphics: MUST retain the Page-Refernce manually
CGPDFPageRetain(SourcePDFPage);
It will fetch the current Page from PDF and then it will retain it.
NSString *relativeOutputFilePath = [NSString stringWithFormat:@”%@/%@%d.png”, directory, outputBaseName, currentPage];
NSString *ImageFileName = [documentsDirectory stringByAppendingPathComponent:relativeOutputFilePath];
It will create a path to save the Images
CGRect sourceRect = CGPDFPageGetBoxRect(SourcePDFPage, kCGPDFMediaBox);
UIGraphicsBeginPDFContextToFile(ImageFileName, sourceRect, nil);
UIGraphicsBeginImageContext(CGSizeMake(sourceRect.size.width,sourceRect.size.height));
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(currentContext, 0.0, sourceRect.size.height); //596,842 //640×960,
CGContextScaleCTM(currentContext, 1.0, -1.0);
CGContextDrawPDFPage (currentContext, SourcePDFPage); // draws the page in the graphics context
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Here, the Current PDF page will be converted into Image.
NSString *imagePath = [documentsDirectory stringByAppendingPathComponent: relativeOutputFilePath];
[UIImagePNGRepresentation(image) writeToFile: imagePath atomically:YES];
It will save the file into the directory.
You may also like:
Related Posts...
GeneralMobile AppsTechnologies
May 29th, 2025
Choosing the right programming language can make all the difference — whether you’re building cutting-edge AI, launching a startup, or simply looking to future-proof your skills. The year 2025 has […]
Read more
May 6th, 2025
Congratulations on embarking on this incredible journey of pregnancy! As your body changes and your little one grows, you might find yourself seeking reliable information and tools to guide you. […]
Read more
May 1st, 2025
The mobile app industry is changing quickly, and Singapore is leading the way in innovation across Southeast Asia. With 2025 on the horizon, businesses must keep up with the latest […]
Read more