/// <summary>
/// The main entry point for the application.
/// </summary>
static void Main()
{
// Initialize PDFNet before calling any other PDFNet function.
PDFNet.Initialize();
string input_path = "../../TestFiles/";
string output_path = "../../TestFiles/Output/";
string input_filename = "US061222892-a.pdf";
PDFDoc pdf_doc = new PDFDoc(input_path + input_filename);
pdf_doc.InitSecurityHandler();
SDFDoc cos_doc = pdf_doc.GetSDFDoc();
int num_objs = cos_doc.XRefSize();
for (int i = 1; i < num_objs; ++i)
{
Obj obj = cos_doc.GetObj(i);
if (obj != null && !obj.IsFree() && obj.IsStream())
{
// Process only images
DictIterator itr = obj.Find("Subtype");
if (!itr.HasNext() || itr.Value().GetName() != "Image")
{
continue;
}
pdftron.PDF.Image input_image = new pdftron.PDF.Image(obj);
pdftron.PDF.Image new_image = null;
// Process only gray-scale images
if (input_image.GetComponentNum() != 1)
{
continue;
}
int bpc = input_image.GetBitsPerComponent();
if (bpc != 1) // Recompress 1 BPC images
{
continue;
}
// Skip images that are already compressed using JBIG2
itr = obj.Find("Filter");
if (itr.HasNext() && itr.Value().IsName() &&
itr.Value().GetName() == "JBIG2Decode")
{
continue;
}
FilterReader reader = new FilterReader(obj.GetDecodedStream());
ObjSet hint_set = new ObjSet();
Obj hint = hint_set.CreateArray();
hint.PushBackName("JBIG2");
hint.PushBackName("Lossless");
hint.PushBackName("Threshold");
hint.PushBackNumber(0.4);
hint.PushBackName("SharePages");
hint.PushBackNumber(10000);
new_image = pdftron.PDF.Image.Create(
cos_doc,
reader,
input_image.GetImageWidth(),
input_image.GetImageHeight(),
1,
ColorSpace.CreateDeviceGray(),
hint // A hint to image encoder to use JBIG2 compression
);
Obj new_img_obj = new_image.GetSDFObj();
// Copy any important entries from the image dictionary
itr = obj.Find("ImageMask");
if (itr.HasNext())
{
new_img_obj.Put("ImageMask", itr.Value());
}
itr = obj.Find("Mask");
if (itr.HasNext())
{
new_img_obj.Put("Mask", itr.Value());
}
cos_doc.Swap(i, new_image.GetSDFObj().GetObjNum());
}
}
pdf_doc.Save(output_path + "US061222892_JBIG2.pdf", SDFDoc.SaveOptions.e_remove_unused);
pdf_doc.Close();
}
static void Main(string[] args)
{
PDFNet.Initialize();
// Example 1:
// Extract images by traversing the display list for
// every page. With this approach it is possible to obtain
// image positioning information and DPI.
try
{
using (PDFDoc doc = new PDFDoc(input_path + "newsletter.pdf"))
using (ElementReader reader = new ElementReader())
{
doc.InitSecurityHandler();
PageIterator itr;
for (itr = doc.GetPageIterator(); itr.HasNext(); itr.Next())
{
reader.Begin(itr.Current());
ImageExtract(doc, reader);
reader.End();
}
Console.WriteLine("Done.");
}
}
catch (PDFNetException e)
{
Console.WriteLine(e.Message);
}
Console.WriteLine("----------------------------------------------------------------");
// Example 2:
// Extract images by scanning the low-level document.
try
{
using (PDFDoc doc = new PDFDoc(input_path + "newsletter.pdf"))
{
doc.InitSecurityHandler();
image_counter = 0;
SDFDoc cos_doc = doc.GetSDFDoc();
int num_objs = cos_doc.XRefSize();
for (int i = 1; i < num_objs; ++i)
{
Obj obj = cos_doc.GetObj(i);
if (obj != null && !obj.IsFree() && obj.IsStream())
{
// Process only images
DictIterator itr = obj.Find("Subtype");
if (!itr.HasNext() || itr.Value().GetName() != "Image")
{
continue;
}
itr = obj.Find("Type");
if (!itr.HasNext() || itr.Value().GetName() != "XObject")
{
continue;
}
pdftron.PDF.Image image = new pdftron.PDF.Image(obj);
Console.WriteLine("--> Image: {0}", ++image_counter);
Console.WriteLine(" Width: {0}", image.GetImageWidth());
Console.WriteLine(" Height: {0}", image.GetImageHeight());
Console.WriteLine(" BPC: {0}", image.GetBitsPerComponent());
string fname = output_path + "image_extract2_" + image_counter.ToString();
image.Export(fname); // or ExporAsPng() or ExporAsTiff() ...
// Convert PDF bitmap to GDI+ Bitmap...
//Bitmap bmp = image.GetBitmap();
//bmp.Save(fname, ImageFormat.Png);
//bmp.Dispose();
// Instead of converting PDF images to a Bitmap, you can also extract
// uncompressed/compressed image data directly using element.GetImageData()
// as illustrated in ElementReaderAdv sample project.
}
}
}
}
catch (PDFNetException e)
{
Console.WriteLine(e.Message);
}
}