It is being reproduced here by permission from Manning Publications. MEAPs are sold exclusively through Manning. All pBook purchases include free PDF, mobi and epub. When mobile formats become available all customers will be contacted and upgraded. Visit Manning. Maybe the same image is added multiple times, in which case passing the PDF through PdfSmartCopy could already result in a serious file size reduction.
You could try and see if the PdfReader method removeUnusedObjects yields any results. Listing 1 uses brute force instead of the PdfReaderContentParser to find images. BufferedImage named bi. We reset all the entries in the image dictionary and we add all the keys that are necessary for a PDF viewer to interpret the image bytes correctly.
Again we get a look at the way iText works internally. When we add a JPEG to a document the normal way, iText selects all the entries for the image dictionary for us. Because of the high complexity, some requirements are close to impossible. We discussed resizing images in a PDF. Then, we created a PdfImageObject that produces a java. Next, we created a second, smaller BufferedImage named img. We reset all the entries in the image dictionary and we added all the keys for a PDF viewer to interpret the image bytes correctly.
The error occures on the line System. FromStream MS ; giving an error of "Parameter is not valid". It may be a standard image format:. Other than that, you'll need to get the raw bytes as you areand build an image using the image stream's width, height, bits per component, number of color components could be CMYK, indexed, RGB, or Something Weirdand a few others, as defined in section 8.
So in some cases your code will work, but in others, it'll fail with the exception you mentioned. Pretty please with sugar on top? Could be useful, when you are going to start play with very powerful library ITextSharp. I think it works when the image is a bitmap but not of any other format. OpenRead "reader. Length ]; fs. Read data0int fs.
Get iTextSharp. MemoryStream bytes ; MS. I have used this library in the past without any problems. Equals String.
Parse textBoxStartPage. Parse textBoxEndPage. Combine Application. Show String. Format "An error occurred. Show string. Format "Cannot open output folder. Save outputPageImageImageFormat.
Png ; args. Drawing ; using System. Imaging ; using System. IO ; using iTextSharp. Image ; using iTextSharp. GetPdfObject pg. Get PdfName. GetPdfObject res. Get name ; if obj.
Resizing an Image in an Existing Document using iText
CreateForXObject new Matrix float. Parse widthfloat. Save msImageFormat. GetImage ; Parser.Select all Open in new window. View solution. View Solution. Why EE? Courses Ask. Get Access. Log In. Web Dev. We help IT Professionals succeed at work. PDF Parser Itextsharp. BeyondBGCM asked. Last Modified: The color depth 1 is not supported. PdfImageO bject. PdfImageO bject. ImageRend erInfo.
ImageRenderListen er. PdfConten tStreamPro cessor. Ima geXObjectD oHandler. PdfReader ContentPar ser. Start Free Trial. View Solution Only. Commented: I guess colour depth 1 isn't supported by the parser, is that a problem? Can you find out what color depth the image uses? Or load it into a higher colour depth perhaps 32 and then convert it to monochrome. It's hard to say because you've given very little information about what the program is doing at this point or what is in the PDF file.
Author Commented: Generic ; using System. Save Path. Add string.The seventh article in my iTextSharp series looks at working with images. This article builds on the previous six which are listed below. There are a number of ways to create images with iTextSharp using the Image.
GetInstance method. Probably the most used option will be to pass a filesystem path and file name into the method:.
MapPath "PDFs". MapPath "Images". Create. Add new Paragraph "GIF". Alternative constructors that you may use include passing a URL or a System.
Image object as opposed to an iTextSharp. Note - the following snippet that System. FromStream method shows the use of namespace aliasing again sd.
FromStream fsas was highlighted in the article Lists with iTextSharp to avoid clashes with the two different types of Image object:. Add new Paragraph "JPG". GetInstance new Uri url. Add new Paragraph "PNG". GetInstance sd. FromStream fsImageFormat. Png. It's difficult to tell from the images I have provided so far, but the resolution of the resulting images in the PDF file is not that great.
By default, images are embedded at 72 dpi Dots Per Inch which coincidentally, matches the number of points in an inch. If this file was being prepared for printing, the final job would be a bit nasty. Generally, commercial printers require that colour images for printing have a resolution of dpi. What you are actually trying to do is squeeze pixels into the space that 72 normally occupies. The image stays the same in terms of file size but occupies less space in the document.
Now, I have a large tif file that I want to use as a logo on an A4 letterhead. It measures x pixels. So at the default 72 dpi, it will measure 4. Increasing the resolution to dpi will reduce the width to 1 inch, and the depth to 2. That part is fine. We can do that using the code above. Now I want to place the dpi image in a particular position on the page. I have in mind the top right hand corner.
The SetAbsolutePosition method will do this, but I need to get a calculator out. SetAbsolutePosition accepts 2 floats as parameters. The first represents the co-ordinate along the X-axis, which starts at the left hand edge of the document and finishes at the right hand edge of the document.Welcome to my new blog! Even though I wrote it back in Septemberit remains my most popular programming post there, simply because of the lack of c code examples online to do this.
Maybe things have changed now, but back when I wrote the original article, I was shocked to find no decent c code examples that reliably, efficiently and quickly extracted images from pdf files. All the samples I found were copies of the same horrendous code, that iterated all the objects in a pdf file this is terribly slow and then used some uneducated guesswork to determine the formats of the image streams it had found. If you take just a moment to think about such a technique, ask yourself where the collection of all embedded objects in the pdf came from.
Most probably, itextsharp used a private method to parse the entire document and build up this collection of all objects. There are plenty of different kinds of objects that can be embedded, so this collection could potentially contain thousands of irrelevant objects. Now you iterate this entire collection again?
A better way would surely be to iterate the pdf pagesand for each page, get a collection of only the images contained by that page, on the fly. As it happens, itextsharp supports this, with their PdfReaderContentParser type. All you need to do is call its ProcessContent method, passing it an instance of their IRenderListener interface which you have to implement each time it processes a page. If you download my PdfUtils. The solution also contains a console application that demonstrates extracting different format images from a pdf file, and saves them to disk.
Pingback: What makes a good blog post? And what makes a blog popular? A Recovered Meth Addict's Blog. This looks like a very, very good solution so far. However, I cannot run it yet as I get the error:.
Like Liked by 1 person. My article relates specifically to the type referenced, that I downloaded when I wrote it. I assume anybody who reads my posts can figure out these things for themselves. And yes, your assumption about the types sounds about right.
I would not be able to answer the comments without being rude and insulting, which is counter to the reasons for sharing knowledge in the first place. Like Like. In any case, I wrote the article because it is not intuitive how to get at just the image objects in a PDF.
Getting the position of elements inside a PDF however, is intuitive, and this is something you should be able to figure out on your own in a couple of minutes, not something to ask random blog writers of tangentially related posts. My ultimate goal is to write a small utility that will automatically remove pages from a PDF if they are blank. And I would determine blankness by the ratio of white to non-white pixels.
That way the ratio could even be adjusted during runtime if needed. At least, as a System. Image descendant. So the embedded format is abstracted from the memory image that you get in the end.
If you then wanted to save it as whatever image format you like, you can use the built-in image encoder classes and save it in whatever supported format you prefer.
Hi Jerome, Thanks for the nice info. It has been Really helpful. However, I need a little more. Is it possible to get the coordinates of the image? Top-left and Bottom-Right? I am trying to locate the rectangle where the image is present with in the pdf.While instantiating this class, you need to pass a PdfDocument object as a parameter to its constructor. To add image to the PDF, create an object of the image that is required to be added and add it using the add method of the Document class.
You can scale an image using the setAutoScale method. This class belongs to the package com. The constructor of this class accepts a string, representing the path of the file where the PDF is to be created. Instantiate the PdfWriter class by passing a string value representing the path where you need to create a PDF to its constructor, as shown below.
When an object of this type is passed to a PdfDocument classevery element added to this document will be written to the file specified. To instantiate this class in writing modeyou need to pass an object of the class PdfWriter to its constructor. Instantiate the PdfDocument class by passing the above created PdfWriter object to its constructor, as shown below.
Once a PdfDocument object is created, you can add various elements like page, font, file attachment, and event handler using the respective methods provided by its class. The Document class of the package com. One of the constructors of this class accepts an object of the class PdfDocument.
Instantiate the Document class by passing the object of the class PdfDocument created in the previous steps, as shown below. To create an image object, first of all, create an ImageData object using the create method of the ImageDataFactory class. As a parameter of this method, pass a string parameter representing the path of the image, as shown below.
Now, instantiate the Image class of the com. While instantiating, pass the ImageData object as a parameter to its constructor, as shown below. Now, add the image object created in the previous step using the add method of the Document class, as shown below.
The following Java program demonstrates how to scale an image with respective to the document size on a PDF document using the iText library. It creates a PDF document with the name autoScale. Previous Page. Next Page. Previous Page Print Page. Dashboard Logout.Sweet … except the flaming scanned images get embedded in damn PDF files.
How do we get those images back out? Naturally, as a programmer I want to open a PDF as a byte stream and decode it all from the ground up. There are several libraries about, but the iTextSharp library sees appropriate since, if I read it right, I can use it provided I make no money from it and I supply the source code.
Tick and tick. This is a zip file containing 7 zip files and a notice. Add a reference to the dll in your project and lets make a start. First, we need to open the pdf file. Guess we need the PdfReader class for that which is derived from IDisposable, so we can start with:. ProcessContentone of whose parameters is a page number. So I feel a for-next loop or something coming on, but how many pages? PdfReader, however, is a low-level reader, think of it as a StreamReader.
What we need is a parser of some kind. ProcessContent requires two parameters — the page number easy and an IRenderListener. So, we just need to create a class on which to implement IRenderListener and pass an instance of that class to ProcessContent. Lets call this new class PdfImageCollection. So, our original loop becomes:. We can dump it to a file, save in a list for later, whatever.
For example, using a test pdf with but a single jpg in it, the pdf file happened to be KB. The resulting extracted jpg was KB. Not that I care for my original purpose. Lets take a closer look at ImageRenderInfo. There is a function GetImageAsBytesthis sounds more interesting. GetImageAsBytes ; Debug. WriteLine String.
So, lets dump that array to a file:. There are, however, more than one image format that a PDF can store.