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I am currently trying to recompress a pdf that has already been created, I am trying to find a way to recompress the images that are in the document, to reduce the file size.
I have been trying to do this with the DataLogics PDE and iTextSharp libraries but I can not find a way to do the stream recompression of the items.
I have though about looping over the xobjects and getting the images and then dropping the DPI down to 96 or using the libjpeg C# implimentation to change the quality of the image but getting it back into the pdf stream seems to always end up, with memory corruption or some other issue.
Any samples will be appreciated.
Thanks
iText and iTextSharp have some methods for replacing indirect objects. Specifically there's PdfReader.KillIndirect() which does what it says and PdfWriter.AddDirectImageSimple(iTextSharp.text.Image, PRIndirectReference) which you can then use to replace what you killed off.
In pseudo C# code you'd do:
var oldImage = PdfReader.GetPdfObject();
var newImage = YourImageCompressionFunction(oldImage);
PdfReader.KillIndirect(oldImage);
yourPdfWriter.AddDirectImageSimple(newImage, (PRIndirectReference)oldImage);
Converting the raw bytes to a .Net image can be tricky, I'll leave that up to you or you can search here. Mark has a good description here. Also, technically PDFs don't have a concept of DPI, that's for printers mostly. See the answer here for more on that.
Using the method above your compression algorithm can actually do two things, physically shrink the image as well as apply JPEG compression. When you physically shrink the image and add it back it will occupy the same amount of space as the original image but with less pixels to work with. This will get you what you consider to be DPI reduction. The JPEG compression speaks for itself.
Below is a full working C# 2010 WinForms app targeting iTextSharp 5.1.1.0. It takes an existing JPEG on your desktop called "LargeImage.jpg" and creates a new PDF from it. Then it opens the PDF, extracts the image, physically shrinks it to 90% of the original size, applies 85% JPEG compression and writes it back to the PDF. See the comments in the code for more of an explanation. The code needs lots more null/error checking. Also looks for NOTE comments where you'll need to expand to handle other situations.
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
using System.IO;
using iTextSharp.text;
using iTextSharp.text.pdf;
namespace WindowsFormsApplication1 {
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e) {
//Our working folder
string workingFolder = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
//Large image to add to sample PDF
string largeImage = Path.Combine(workingFolder, "LargeImage.jpg");
//Name of large PDF to create
string largePDF = Path.Combine(workingFolder, "Large.pdf");
//Name of compressed PDF to create
string smallPDF = Path.Combine(workingFolder, "Small.pdf");
//Create a sample PDF containing our large image, for demo purposes only, nothing special here
using (FileStream fs = new FileStream(largePDF, FileMode.Create, FileAccess.Write, FileShare.None)) {
using (Document doc = new Document()) {
using (PdfWriter writer = PdfWriter.GetInstance(doc, fs)) {
doc.Open();
iTextSharp.text.Image importImage = iTextSharp.text.Image.GetInstance(largeImage);
doc.SetPageSize(new iTextSharp.text.Rectangle(0, 0, importImage.Width, importImage.Height));
doc.SetMargins(0, 0, 0, 0);
doc.NewPage();
doc.Add(importImage);
doc.Close();
}
}
}
//Now we're going to open the above PDF and compress things
//Bind a reader to our large PDF
PdfReader reader = new PdfReader(largePDF);
//Create our output PDF
using (FileStream fs = new FileStream(smallPDF, FileMode.Create, FileAccess.Write, FileShare.None)) {
//Bind a stamper to the file and our reader
using (PdfStamper stamper = new PdfStamper(reader, fs)) {
//NOTE: This code only deals with page 1, you'd want to loop more for your code
//Get page 1
PdfDictionary page = reader.GetPageN(1);
//Get the xobject structure
PdfDictionary resources = (PdfDictionary)PdfReader.GetPdfObject(page.Get(PdfName.RESOURCES));
PdfDictionary xobject = (PdfDictionary)PdfReader.GetPdfObject(resources.Get(PdfName.XOBJECT));
if (xobject != null) {
PdfObject obj;
//Loop through each key
foreach (PdfName name in xobject.Keys) {
obj = xobject.Get(name);
if (obj.IsIndirect()) {
//Get the current key as a PDF object
PdfDictionary imgObject = (PdfDictionary)PdfReader.GetPdfObject(obj);
//See if its an image
if (imgObject.Get(PdfName.SUBTYPE).Equals(PdfName.IMAGE)) {
//NOTE: There's a bunch of different types of filters, I'm only handing the simplest one here which is basically raw JPG, you'll have to research others
if (imgObject.Get(PdfName.FILTER).Equals(PdfName.DCTDECODE)) {
//Get the raw bytes of the current image
byte[] oldBytes = PdfReader.GetStreamBytesRaw((PRStream)imgObject);
//Will hold bytes of the compressed image later
byte[] newBytes;
//Wrap a stream around our original image
using (MemoryStream sourceMS = new MemoryStream(oldBytes)) {
//Convert the bytes into a .Net image
using (System.Drawing.Image oldImage = Bitmap.FromStream(sourceMS)) {
//Shrink the image to 90% of the original
using (System.Drawing.Image newImage = ShrinkImage(oldImage, 0.9f)) {
//Convert the image to bytes using JPG at 85%
newBytes = ConvertImageToBytes(newImage, 85);
}
}
}
//Create a new iTextSharp image from our bytes
iTextSharp.text.Image compressedImage = iTextSharp.text.Image.GetInstance(newBytes);
//Kill off the old image
PdfReader.KillIndirect(obj);
//Add our image in its place
stamper.Writer.AddDirectImageSimple(compressedImage, (PRIndirectReference)obj);
}
}
}
}
}
}
}
this.Close();
}
//Standard image save code from MSDN, returns a byte array
private static byte[] ConvertImageToBytes(System.Drawing.Image image, long compressionLevel) {
if (compressionLevel < 0) {
compressionLevel = 0;
} else if (compressionLevel > 100) {
compressionLevel = 100;
}
ImageCodecInfo jgpEncoder = GetEncoder(ImageFormat.Jpeg);
System.Drawing.Imaging.Encoder myEncoder = System.Drawing.Imaging.Encoder.Quality;
EncoderParameters myEncoderParameters = new EncoderParameters(1);
EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, compressionLevel);
myEncoderParameters.Param[0] = myEncoderParameter;
using (MemoryStream ms = new MemoryStream()) {
image.Save(ms, jgpEncoder, myEncoderParameters);
return ms.ToArray();
}
}
//standard code from MSDN
private static ImageCodecInfo GetEncoder(ImageFormat format) {
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
foreach (ImageCodecInfo codec in codecs) {
if (codec.FormatID == format.Guid) {
return codec;
}
}
return null;
}
//Standard high quality thumbnail generation from http://weblogs.asp.net/gunnarpeipman/archive/2009/04/02/resizing-images-without-loss-of-quality.aspx
private static System.Drawing.Image ShrinkImage(System.Drawing.Image sourceImage, float scaleFactor) {
int newWidth = Convert.ToInt32(sourceImage.Width * scaleFactor);
int newHeight = Convert.ToInt32(sourceImage.Height * scaleFactor);
var thumbnailBitmap = new Bitmap(newWidth, newHeight);
using (Graphics g = Graphics.FromImage(thumbnailBitmap)) {
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
System.Drawing.Rectangle imageRectangle = new System.Drawing.Rectangle(0, 0, newWidth, newHeight);
g.DrawImage(sourceImage, imageRectangle);
}
return thumbnailBitmap;
}
}
}
I don't know about iTextSharp, but you have to rewrite a PDF file if anything is changed, as it contains an xref table (index) with the exact file position of each object. This means if even one byte is added or removed, the PDF becomes corrupted.
Your best bet for recompressing the images is JBIG2 if they are B&W, or JPEG2000 otherwise, for which Jasper library will happily encode JPEG2000 codestreams for placement into PDF files at whatever quality you so desire.
If it were me I'd do it all from code without the PDF libraries. Just find all images (anything between stream and endstream after an occurance of JPXDecode (JPEG2000), JBIG2Decode (JBIG2) or DCTDecode (JPEG)) pull that out, reencode it with Jasper, then stick it back in again and update the xref table.
To update the xref table, find the positions of each object (starting 00001 0 obj) and just update the new positions in the xref table. It's not too much work, less than it sounds. You might be able to get all the offsets with a single regular expression (I'm not a C# programmer, but in PHP it would be that simple.)
Then finally update the value of the startxref tag in the trailer with the offset of the beginning of the xref table (where it says xref in the file).
Otherwise you'll end up decoding the entire PDF and rewriting it all, which will be slow, and you might lose something along the way.
There is an example on how to find and replace images in an existing PDF by the creator of iText. It's actually a small excerpt from his book. Since it's in Java, here's a simple replacement:
public void ReduceResolution(PdfReader reader, long quality) {
int n = reader.XrefSize;
for (int i = 0; i < n; i++) {
PdfObject obj = reader.GetPdfObject(i);
if (obj == null || !obj.IsStream()) {continue;}
PdfDictionary dict = (PdfDictionary)PdfReader.GetPdfObject(obj);
PdfName subType = (PdfName)PdfReader.GetPdfObject(
dict.Get(PdfName.SUBTYPE)
);
if (!PdfName.IMAGE.Equals(subType)) {continue;}
PRStream stream = (PRStream )obj;
try {
PdfImageObject image = new PdfImageObject(stream);
PdfName filter = (PdfName) image.Get(PdfName.FILTER);
if (
PdfName.JBIG2DECODE.Equals(filter)
|| PdfName.JPXDECODE.Equals(filter)
|| PdfName.CCITTFAXDECODE.Equals(filter)
|| PdfName.FLATEDECODE.Equals(filter)
) continue;
System.Drawing.Image img = image.GetDrawingImage();
if (img == null) continue;
var ll = image.GetImageBytesType();
int width = img.Width;
int height = img.Height;
using (System.Drawing.Bitmap dotnetImg =
new System.Drawing.Bitmap(img))
{
// set codec to jpeg type => jpeg index codec is "1"
System.Drawing.Imaging.ImageCodecInfo codec =
System.Drawing.Imaging.ImageCodecInfo.GetImageEncoders()[1];
// set parameters for image quality
System.Drawing.Imaging.EncoderParameters eParams =
new System.Drawing.Imaging.EncoderParameters(1);
eParams.Param[0] =
new System.Drawing.Imaging.EncoderParameter(
System.Drawing.Imaging.Encoder.Quality, quality
);
using (MemoryStream msImg = new MemoryStream()) {
dotnetImg.Save(msImg, codec, eParams);
msImg.Position = 0;
stream.SetData(msImg.ToArray());
stream.SetData(
msImg.ToArray(), false, PRStream.BEST_COMPRESSION
);
stream.Put(PdfName.TYPE, PdfName.XOBJECT);
stream.Put(PdfName.SUBTYPE, PdfName.IMAGE);
stream.Put(PdfName.FILTER, filter);
stream.Put(PdfName.FILTER, PdfName.DCTDECODE);
stream.Put(PdfName.WIDTH, new PdfNumber(width));
stream.Put(PdfName.HEIGHT, new PdfNumber(height));
stream.Put(PdfName.BITSPERCOMPONENT, new PdfNumber(8));
stream.Put(PdfName.COLORSPACE, PdfName.DEVICERGB);
}
}
}
catch {
// throw;
// iText[Sharp] can't handle all image types...
}
finally {
// may or may not help
reader.RemoveUnusedObjects();
}
}
}
You'll notice it's only handling JPEG. The logic is reversed (instead of explicitly handling only DCTDECODE/JPEG) so you can uncomment some of the ignored image types and experiment with the PdfImageObject in the code above. In particular, most of the FLATEDECODE images (.bmp, .png, and .gif) are represented as PNG (confirmed in the DecodeImageBytes method of the PdfImageObject source code). As far as I know, .NET does not support PNG encoding. There are some references to support this here and here. You can try a stand-alone PNG optimization executable, but you also have to figure out how to set PdfName.BITSPERCOMPONENT and PdfName.COLORSPACE in the PRStream.
For completeness sake, since your question specifically asks about PDF compression, here's how you compress a PDF with iTextSharp:
PdfStamper stamper = new PdfStamper(
reader, YOUR-STREAM, PdfWriter.VERSION_1_5
);
stamper.Writer.CompressionLevel = 9;
int total = reader.NumberOfPages + 1;
for (int i = 1; i < total; i++) {
reader.SetPageContent(i, reader.GetPageContent(i));
}
stamper.SetFullCompression();
stamper.Close();
You might also try and run the PDF through PdfSmartCopy to get the file size down. It removes redundant resources, but like the call to RemoveUnusedObjects() in the finally block, it may or may not help. That will depend on how the PDF was created.
IIRC iText[Sharp] doesn't deal well with JBIG2DECODE, so #Alasdair's suggestion looks good - if you want to take the time learning the Jasper library and using the brute-force approach.
Good luck.
EDIT - 2012-08-17, comment by #Craig:
To save the PDF after compressing the jpegs using the ReduceResolution() method above:
a. Instantiate a PdfReader object:
PdfReader reader = new PdfReader(pdf);
b. Pass the PdfReader to the ReduceResolution() method above.
c. Pass the altered PdfReader to a PdfStamper. Here's one way using a MemoryStream:
// Save altered PDF. then you can pass the btye array to a database, etc
using (MemoryStream ms = new MemoryStream()) {
using (PdfStamper stamper = new PdfStamper(reader, ms)) {
}
return ms.ToArray();
}
Or you can use any other Stream if you don't need to keep the PDF in memory. E.g. use a FileStream and save directly to disk.
I've written a library to do just that. It will also OCR the pdf's using Tesseract or Cuneiform and create searchable, compressed PDF files. It's a library that uses several open source projects (iTextsharp, jbig2 encoder, Aforge, muPDF#) to complete the task. You can check it out here http://hocrtopdf.codeplex.com/
I am not sure if you are considering other libraries, but you can easily recompress existing images using Docotic.Pdf library (Disclaimer: I work for the company).
Here is some sample code:
static void RecompressExistingImages(string fileName, string outputName)
{
using (PdfDocument doc = new PdfDocument(fileName))
{
foreach (PdfImage image in doc.Images)
image.RecompressWithGroup4Fax();
doc.Save(outputName);
}
}
There are also RecompressWithFlate, RecompressWithGroup3Fax, RecompressWithJpeg and Uncompress methods.
The library will convert color images to bilevel ones if needed. You can specify deflate compression level, JPEG quality etc.
I am also ask you to think twice before using approach suggested by #Alasdair. If you are going to deal with PDF files that weren't created by you than the task is far more complex that it might seem.
To start with, there is great deal of images compressed by codecs other than JPXDecode, JBIG2Decode or DCTDecode. And PDF can also contain inline images.
PDF files saved using newer versions of standard (1.5 or newer) can contain cross-reference streams. It means that reading and updating such files is more complex than just finding/updating some numbers at the end of the file.
So, please, use a PDF library.
A simple way to compress PDF is using gsdll32.dll (Ghostscript) and Cyotek.GhostScript.dll (wrapper):
public static void CompressPDF(string sInFile, string sOutFile, int iResolution)
{
string[] arg = new string[]
{
"-sDEVICE=pdfwrite",
"-dNOPAUSE",
"-dSAFER",
"-dBATCH",
"-dCompatibilityLevel=1.5",
"-dDownsampleColorImages=true",
"-dDownsampleGrayImages=true",
"-dDownsampleMonoImages=true",
"-sPAPERSIZE=a4",
"-dPDFFitPage",
"-dDOINTERPOLATE",
"-dColorImageDownsampleThreshold=1.0",
"-dGrayImageDownsampleThreshold=1.0",
"-dMonoImageDownsampleThreshold=1.0",
"-dColorImageResolution=" + iResolution.ToString(),
"-dGrayImageResolution=" + iResolution.ToString(),
"-dMonoImageResolution=" + iResolution.ToString(),
"-sOutputFile=" + sOutFile,
sInFile
};
using(GhostScriptAPI api = new GhostScriptAPI())
{
api.Execute(arg);
}
}
Related
I am trying to create a linear DNG file based on JPG using Lossy JPEG (34892) compression (which was introduced in DNG 1.4.0.0). After running the method below I got an error "Error: File format is invalid (JPEG dimensions do not match tile)" from dng_validate.exe.
It would be nice if someone can resolve it by adjusting my code. Also, I will be happy for a tutorial link. Using of image tools (magick, dcraw, exiftool) also could be a solution.
public static void LinearRawDng()
{
string file = "eva.jpg";
using (Tiff tif = Tiff.Open("eva-linear.dng", "w"))
{
Image img = Image.FromFile(file);
byte[] raster;
using (MemoryStream ms = new MemoryStream())
{
img.Save(ms, ImageFormat.Jpeg);
raster = ms.ToArray();
}
tif.SetField(TiffTag.MAKE, "Fitler");
tif.SetField(TiffTag.UNIQUECAMERAMODEL, "Fitler");
tif.SetField(TiffTag.DNGVERSION, "\x1\x4\x0\x0");
tif.SetField(TiffTag.DNGBACKWARDVERSION, "\x1\x4\x0\x0");
tif.SetField(TiffTag.SUBFILETYPE, 0);
tif.SetField(TiffTag.PHOTOMETRIC, 34892);
tif.SetField(TiffTag.COMPRESSION, 34892);
tif.SetField(TiffTag.SAMPLESPERPIXEL, 1);
tif.SetField(TiffTag.BITSPERSAMPLE, 8);
tif.SetField(TiffTag.ORIENTATION, Orientation.TOPLEFT);
tif.SetField(TiffTag.PLANARCONFIG, PlanarConfig.CONTIG);
tif.SetField(TiffTag.IMAGEWIDTH, img.Width);
tif.SetField(TiffTag.IMAGELENGTH, img.Height);
var result = tif.WriteRawStrip(0, raster, raster.Length);
tif.Close();
Console.WriteLine("Finished");
}
}
What I am trying to accomplish is allowing my user to upload a PDF. I will then convert that to an Image and get the Images byte array. Below is what I have so far.
PdfDocumentProcessor pdfDocumentProcessor = new PdfDocumentProcessor();
using (MemoryStream ms = new MemoryStream(e.UploadedFile.FileBytes))
{
pdfDocumentProcessor.LoadDocument(ms);
for (int i = 1; i <= pdfDocumentProcessor.Document.Pages.Count; i++)
{
Bitmap image = pdfDocumentProcessor.CreateBitmap(i, 1000);
try
{
image.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
}
catch (Exception error)
{
string message = error.Message;
}
}
When I try to save the Image to the memory stream I am getting the error "A generic error occurred in GDI+" I believe this has something to do with me not specifying a path for the image to be saved to, but I could be mistaken.
I want to convert the PDF to and Image, then get the byte array of the image, and save that to the database. I really don't want to save the image to a specified path.
PDFDocumentProcessor is a DevExpress class that pulls in the PDF and also will give me the PDF's byte array, but I just can't seem to find a way past the save error to retrieve an Image byte array
Any help is appreciated thank you
The issue is likely caused by you trying to re-use the same MemoryStream that is holding the input file bytes. You should create a new memory stream to save to.
I don't have access to devexpress but I grabbed another Nuget package that i am associated with https://www.nuget.org/packages/Leadtools.Pdf/ and tested it and this code works to save the PDF to a PNG memorystream:
using (var ms = new MemoryStream(fileBytes))
using (var codecs = new RasterCodecs())
{
codecs.Options.Load.AllPages = true;
using (var rasterImage = codecs.Load(ms))
using (var outputStream = new MemoryStream())
codecs.Save(rasterImage, outputStream, RasterImageFormat.Png, 0);
}
So I want to know how to print my entire WPF page to a PDF file with PDFSharp.
I've already been looking at several articles but I can't seem to figure it out.
I want the pdf to look something like this:
I've already looked up on articles about drawing strings, lines name it. But creating every line, string and shape individually looks like a sloppy and bad idea to me.
Can anyone help me with this?
Articles will also be appreciated!
Thanks in advance
I Would say first export your control to image with RenderTargetBitmap and then use a library to export it to PDF.
Maybe this sample might help ?
http://www.techcognition.com/post/Create-PDF-File-From-WPF-Window-using-iTextsharp-1001
With this library
Here his the Control to Image class I'm using with sucess (I'm able to get a PNG snapshot of complex UI controls implying a very deep parent-child hierarchy)
The source is a WPF control container (usercontrol, grid, wahtever).
The path is the full path for PNG output file (C:\Temp\myImage.png)
public class ControlToImageSnapshot
{
/// <summary>
/// Conversion du controle en image PNG
/// </summary>
/// <param name="source">Contrôle à exporter</param>
/// <param name="path">Destination de l'export</param>
/// <param name="zoom">Taille désirée</param>
public static void SnapShotPng(FrameworkElement source, string path, double zoom = 1.0)
{
try
{
var dir = Path.GetDirectoryName(path);
if (dir != null && !Directory.Exists(dir))
{
Directory.CreateDirectory(dir);
}
RenderTargetBitmap renderTarget = new RenderTargetBitmap((int)source.ActualWidth, (int)source.ActualHeight, 96, 96, PixelFormats.Pbgra32);
VisualBrush sourceBrush = new VisualBrush(source);
DrawingVisual drawingVisual = new DrawingVisual();
DrawingContext drawingContext = drawingVisual.RenderOpen();
using (drawingContext)
{
drawingContext.DrawRectangle(sourceBrush, null, new Rect(new Point(0, 0), new Point(source.ActualWidth, source.ActualHeight)));
}
renderTarget.Render(drawingVisual);
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(renderTarget));
using (FileStream stream = new FileStream(path, FileMode.Create, FileAccess.Write))
{
encoder.Save(stream);
}
createPdfFromImage(path, #"C:\Temp\myfile.pdf");
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
public static void createPdfFromImage(string imageFile, string pdfFile)
{
using (var ms = new MemoryStream())
{
var document = new iTextSharp.text.Document(iTextSharp.text.PageSize.LETTER.Rotate(), 0, 0, 0, 0);
PdfWriter.GetInstance(document, new FileStream(pdfFile, FileMode.Create));
iTextSharp.text.pdf.PdfWriter.GetInstance(document, ms).SetFullCompression();
document.Open();
FileStream fs = new FileStream(imageFile, FileMode.Open);
var image = iTextSharp.text.Image.GetInstance(fs);
image.ScaleToFit(document.PageSize.Width, document.PageSize.Height);
document.Add(image);
document.Close();
//open pdf file
Process.Start("explorer.exe", pdfFile);
}
}
}
For pdfsharp its quite easy, you can pass in an array of bytes for the pdf image and pdf, ive used this function quite a lot when dealing with images in pdfsharp.
fairly self explanatory
Open pdf and the image into a memorystream
Get pdf setup and choose page to draw on
I always set interpolate to false, I get better results with the kind of images I'm dealing with, if you have shading in your image set it to true.
then all your left to do is draw the image on the pdf and return as a memorystream
public static byte[] AddImageToPdf(byte[] pdf, byte[] img, double x, double y)
{
using (var msPdf = new MemoryStream(pdf))
{
using (var msImg = new MemoryStream(img))
{
var image = Image.FromStream(msImg);
var document = PdfReader.Open(msPdf);
var page = document.Pages[0];
var gfx = XGraphics.FromPdfPage(page);
var ximg = XImage.FromGdiPlusImage(image);
ximg.Interpolate = false;
gfx.DrawImage(
ximg,
XUnit.FromCentimeter(x),
XUnit.FromCentimeter(y),
ximg.PixelWidth * 72 / ximg.HorizontalResolution,
ximg.PixelHeight * 72 / ximg.HorizontalResolution);
using (var msFinal = new MemoryStream())
{
document.Save(msFinal);
return msFinal.ToArray();
}
}
}
}
its hardcoded for page 1 in the pdf, easily extendable to pass in pages if you want, ill leave that as an exercise for yourself, at the end you get a nice byte array containing your pdf, no files need to touch the ground enroute if you import your image as a memorystream from your control and pass it in. another answer in this topic has a good way of getting the control image.
I have a TIFF file with two pages. When I convert the file to JPG format I lose the second page. Is there any way to put two images from a TIFF file into one JPG file?
Because TIFF files are too big, I have to decrease their sizes. Is there any way to decrease TIFF size programmatically? That could also help solve my problem.
Since a TIFF can contain multiple frames but JPG can't, you need to convert each single frame into a JPG.
Taken from Windows Dev Center Samples:
public static string[] ConvertTiffToJpeg(string fileName)
{
using (Image imageFile = Image.FromFile(fileName))
{
FrameDimension frameDimensions = new FrameDimension(
imageFile.FrameDimensionsList[0]);
// Gets the number of pages from the tiff image (if multipage)
int frameNum = imageFile.GetFrameCount(frameDimensions);
string[] jpegPaths = new string[frameNum];
for (int frame = 0; frame < frameNum; frame++)
{
// Selects one frame at a time and save as jpeg.
imageFile.SelectActiveFrame(frameDimensions, frame);
using (Bitmap bmp = new Bitmap(imageFile))
{
jpegPaths[frame] = String.Format("{0}\\{1}{2}.jpg",
Path.GetDirectoryName(fileName),
Path.GetFileNameWithoutExtension(fileName),
frame);
bmp.Save(jpegPaths[frame], ImageFormat.Jpeg);
}
}
return jpegPaths;
}
}
using System.Drawing;
using System.Drawing.Imaging;
Bitmap bm=Bitmap.FromFile("photo.tif");
bm.Save("photo.jpg",ImageFormat.Jpeg);
public static class ConvertTiffToJpeg
{
static string base64String = null;
public static string ImageToBase64(string tifpath)
{
string path = tifpath;
using (System.Drawing.Image image = System.Drawing.Image.FromFile(path))
{
using (MemoryStream m = new MemoryStream())
{
image.Save(m, ImageFormat.Jpeg);
byte[] imageBytes = m.ToArray();
base64String = Convert.ToBase64String(imageBytes);
return base64String;
}
}
}
}
< img src="data:image/jpeg;base64, #ConvertTiffToJpeg.ImageToBase64(#"c:\sample.tif")"/>
c# .net tiff-to-jpeg tiff
We faced some problems when converting TIF files to JPEG, because TIF format supports some types of compressions that are not supported in free toolkits.
I searched the internet and tried some commercial toolkits, but most of them are hard to implement with many limitations. The toolkit that drew my attention is leadtools, because it supports loading and saving many file formats (including TIF images with different compressions). We used this toolkit convert our images to JPEG format. You can find more information in the following page:
http://support.leadtools.com/CS/forums/8925/ShowPost.aspx
Note that you can convert any VB.Net code to C# by using this free code converter:
http://www.developerfusion.com/tools/convert/vb-to-csharp/
On some .JPG files (EPS previews, generated by Adobe Illustrator) in Windows 7 InPlaceBitmapMetadataWriter.TrySave() returns true after some SetQuery() calls, but does nothing.
Code sample:
BitmapDecoder decoder;
BitmapFrame frame;
BitmapMetadata metadata;
InPlaceBitmapMetadataWriter writer;
decoder = BitmapDecoder.Create(s, BitmapCreateOptions.PreservePixelFormat | BitmapCreateOptions.IgnoreColorProfile, BitmapCacheOption.Default);
frame = decoder.Frames[0];
metadata = frame.Metadata as BitmapMetadata;
writer = frame.CreateInPlaceBitmapMetadataWriter();
try {
writer.SetQuery("System.Title", title);
writer.SetQuery(#"/app1/ifd/{ushort=" + exiftagids[0] + "} ", (title + '\0').ToCharArray());
writer.SetQuery(#"/app13/irb/8bimiptc/iptc/object name", title);
return writer.TrySave();
}
catch {
return false;
}
Image sample
You can reproduce problem (if you have Windows 7) by downloading image sample and using this code sample to set title on this image.
Image has enough room for metadata - and this code sample works fine on my WinXP.
Same code works fine on Win7 with other .JPG files.
Any ideas are welcome :)
Two things:
I don't think you will be able to write to your metadata variable just like that, as it will be Frozen. So, you will have to clone it:
BitmapMetadata metadata = frame.Metadata.Clone() as BitmapMetadata;
Padding, you need padding. I found this out after about a day's worth of tinkering around trying to make some code (similar to yours) work. InPlaceBitmapMetadataWriter will not work if there is no metadata padding in your image file. So you need something like:
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
if(frame != null && metadata != null) {
metadata.SetQuery("/app1/ifd/PaddingSchema:Padding", padding);
encoder.Frames.Add(BitmapFrame.Create(frame, frame.Thumbnail, metadata, frame.ColorContexts));
using (Stream outputFile = File.Open(_myoutputpath, FileMode.Create, FileAccess.ReadWrite)) {
encoder.Save(outputFile);
}
}
Now you can use the file located at _myoutputpath which has added metadata padding for your InPlaceBitmapMetadataWriter operations.
This article and attached code should help you out.
Hi I found this article about InPlaceBitmapMetadataWriter where the guy said that TrySave() might corrupt the image and that's why he advised to do TrySave() on the copy of the original file and if this doesn't work, add padding to the copy of original file and than TrySave() again and if it works, delete the original and rename the copy.
I scratched my head and asked myself why I should bother with InPlaceBitmapMetadataWriter and writing 3x original file to the disk in case TrySave() doesn't work because there is not enough padding, if I can clone metadata, write whatever into them and assemble jpeg file right away.
Then I started to think that maybe thanks to InPlaceBitmapMetadataWriter I can edit metadata without losing quality, but it looks like it "just" helps you to write metadata more quickly if there is enough padding.
I wrote a small test where I compress one file many times to see the quality degradation and you can see it in the third-fourth compression, which is very bad.
But luckily, if you always use same QualityLevel with JpegBitmapEncoder there is no degradation.
In this example I rewrite keywords 100x in metadata and the quality seems not to change.
private void LosslessJpegTest() {
var original = "d:\\!test\\TestInTest\\20150205_123011.jpg";
var copy = original;
const BitmapCreateOptions createOptions = BitmapCreateOptions.PreservePixelFormat | BitmapCreateOptions.IgnoreColorProfile;
for (int i = 0; i < 100; i++) {
using (Stream originalFileStream = File.Open(copy, FileMode.Open, FileAccess.Read)) {
BitmapDecoder decoder = BitmapDecoder.Create(originalFileStream, createOptions, BitmapCacheOption.None);
if (decoder.CodecInfo == null || !decoder.CodecInfo.FileExtensions.Contains("jpg") || decoder.Frames[0] == null)
continue;
BitmapMetadata metadata = decoder.Frames[0].Metadata == null
? new BitmapMetadata("jpg")
: decoder.Frames[0].Metadata.Clone() as BitmapMetadata;
if (metadata == null) continue;
var keywords = metadata.Keywords == null ? new List<string>() : new List<string>(metadata.Keywords);
keywords.Add($"Keyword {i:000}");
metadata.Keywords = new ReadOnlyCollection<string>(keywords);
JpegBitmapEncoder encoder = new JpegBitmapEncoder {QualityLevel = 80};
encoder.Frames.Add(BitmapFrame.Create(decoder.Frames[0], decoder.Frames[0].Thumbnail, metadata,
decoder.Frames[0].ColorContexts));
copy = original.Replace(".", $"_{i:000}.");
using (Stream newFileStream = File.Open(copy, FileMode.Create, FileAccess.ReadWrite)) {
encoder.Save(newFileStream);
}
}
}
}
I still didn't find the answer and has to write wrapper for exiftool instead of using WPF's way to work with metadata...
May be som1 will find it useful.