I have a template DOCX file that I am working with. The template file contains two placeholders for images (a logo and a barcode image). How can I replace these images using BufferedImage or just getting an image from a URL? There seem to not be many resources on this.
I finally got it to work using bookmarks. Apparently I didn't dig deeper before posting the question. The code is below. Although I did not find the methods to control the width and height of the image, which is important, the code below does answer my question.
public void addLogoAndBarCode(WordprocessingMLPackage pack, String agencyID)
{
MainDocumentPart documentPart = pack.getMainDocumentPart();
Document wmlDoc = (Document) documentPart.getJaxbElement();
Body body = wmlDoc.getBody();
List<Object> paragraphs = body.getContent();
RangeFinder rt = new RangeFinder("CTBookmark", "CTMarkupRange");
new TraversalUtil(paragraphs, rt);
for(CTBookmark bm:rt.getStarts())
{
if(bm.getName().equals("agencyLogo"))
{
logger.info("i found bookmark");
try
{
InputStream is = new FileInputStream(agencyLogoPath+agencyID+".jpg");
byte[] bytes = IOUtils.toByteArray(is);
BinaryPartAbstractImage imagePart = BinaryPartAbstractImage.createImagePart(pack, bytes);
Inline inline = imagePart.createImageInline(null, null, 0,1, false, 800);
P p = (P)(bm.getParent());
ObjectFactory factory = new ObjectFactory();
R run = factory.createR();
Drawing drawing = factory.createDrawing();
drawing.getAnchorOrInline().add(inline);
run.getContent().add(drawing);
p.getContent().add(run);
}
catch(Exception er)
{
er.printStackTrace();
}
}
}
}
Related
I have an existing library that I can use to receive a docx file and return it. The software is .Net Core hosted in a Linux Docker container.
It's very limited in scope though and I need to perform some actions it can't do. As these are straightforward I thought I would use OpenXML, and for my proof of concept all I need to do is to read a docx as a memorystream, replace some text, turn it back into a memorystream and return it.
However the docx that gets returned is unreadable. I've commented out the text replacement below to eliminate that, and if I comment out the call to the method below then the docx can be read so I'm sure the issue is in this method.
Presumably I'm doing something fundamentally wrong here but after a few hours googling and playing around with the code I am not sure how to correct this; any ideas what I have wrong?
Thanks for the help
private MemoryStream SearchAndReplace(MemoryStream mem)
{
mem.Position = 0;
using (WordprocessingDocument wordDoc = WordprocessingDocument.Open(mem, true))
{
string docText = null;
StreamReader sr = new StreamReader(wordDoc.MainDocumentPart.GetStream());
docText = sr.ReadToEnd();
//Regex regexText = new Regex("Hello world!");
//docText = regexText.Replace(docText, "Hi Everyone!");
MemoryStream newMem = new MemoryStream();
newMem.Position = 0;
StreamWriter sw = new StreamWriter(newMem);
sw.Write(docText);
return newMem;
}
}
If your real requirement is to search and replace text in a WordprocessingDocument, you should have a look at this answer.
The following unit test shows how you can make your approach work if the use case really demands that you read a string from a part, "massage" the string, and write the changed string back to the part. It also shows one of the shortcomings of any other approach than the one described in the answer already mentioned above, e.g., by demonstrating that the string "Hello world!" will not be found in this way if it is split across w:r elements.
[Fact]
public void CanSearchAndReplaceStringInOpenXmlPartAlthoughThisIsNotTheWayToSearchAndReplaceText()
{
// Arrange.
using var docxStream = new MemoryStream();
using (var wordDocument = WordprocessingDocument.Create(docxStream, WordprocessingDocumentType.Document))
{
MainDocumentPart part = wordDocument.AddMainDocumentPart();
var p1 = new Paragraph(
new Run(
new Text("Hello world!")));
var p2 = new Paragraph(
new Run(
new Text("Hello ") { Space = SpaceProcessingModeValues.Preserve }),
new Run(
new Text("world!")));
part.Document = new Document(new Body(p1, p2));
Assert.Equal("Hello world!", p1.InnerText);
Assert.Equal("Hello world!", p2.InnerText);
}
// Act.
SearchAndReplace(docxStream);
// Assert.
using (WordprocessingDocument wordDocument = WordprocessingDocument.Open(docxStream, false))
{
MainDocumentPart part = wordDocument.MainDocumentPart;
Paragraph p1 = part.Document.Descendants<Paragraph>().First();
Paragraph p2 = part.Document.Descendants<Paragraph>().Last();
Assert.Equal("Hi Everyone!", p1.InnerText);
Assert.Equal("Hello world!", p2.InnerText);
}
}
private static void SearchAndReplace(MemoryStream docxStream)
{
using (WordprocessingDocument wordDocument = WordprocessingDocument.Open(docxStream, true))
{
// If you wanted to read the part's contents as text, this is how you
// would do it.
string partText = ReadPartText(wordDocument.MainDocumentPart);
// Note that this is not the way in which you should search and replace
// text in Open XML documents. The text might be split across multiple
// w:r elements, so you would not find the text in that case.
var regex = new Regex("Hello world!");
partText = regex.Replace(partText, "Hi Everyone!");
// If you wanted to write changed text back to the part, this is how
// you would do it.
WritePartText(wordDocument.MainDocumentPart, partText);
}
docxStream.Seek(0, SeekOrigin.Begin);
}
private static string ReadPartText(OpenXmlPart part)
{
using Stream partStream = part.GetStream(FileMode.OpenOrCreate, FileAccess.Read);
using var sr = new StreamReader(partStream);
return sr.ReadToEnd();
}
private static void WritePartText(OpenXmlPart part, string text)
{
using Stream partStream = part.GetStream(FileMode.Create, FileAccess.Write);
using var sw = new StreamWriter(partStream);
sw.Write(text);
}
Currently I am using a custom LocationTextExtractionStrategy to extract text from a PDF that returns a TextRenderInfo[]. I would like to be able to determine if a TextRenderInfo object (or PDFString, child of TextRenderInfo) appears in a specific layer. I am not sure if this is possible. To get the layers in a PDF, I am using:
Dictionary<string,PdfLayer> layers;
using (var pdfReader = new PdfReader(src))
{
var newSrc = Path.Combine(["new file location"]);
using (var stream = new FileStream(newSrc, FileMode.Create))
{
PdfStamper stamper = new PdfStamper(pdfReader, stream);
layers = stamper.GetPdfLayers();
stamper.Close();
}
pdfReader.Close();
src = newSrc;
}
To extract the text, I am using:
var textExtractor = new TextExtractionStrategy();
PdfTextExtractor.GetTextFromPage(pdfReader, pdfPageNum,textExtractor);
List<TextRenderInfo> results = textExtractor.Results;
Is there any way that I can check if the individual TextRenderInfo results exist within the layers obtained in the first code snippet. Any help would be much appreciated.
It is possible to get the contents from a single layer, but you'll have to jump through a few hoops to work it out. Specifically, you will have to recreate some of the logic that is provided by the PdfTextExtractor and PdfReaderContentParser.
public static String GetText(PdfReader reader, int pageNumber, int streamNumber) {
var strategy = new LocationTextExtractionStrategy();
var processor = new PdfContentStreamProcessor(strategy);
var resourcesDic = pageDic.GetAsDict(PdfName.RESOURCES);
// assuming you still need to extract the page bytes
byte[] contents = GetContentBytesForPageStream(reader, pageNumber, streamNumber);
processor.ProcessContent(contents, resourcesDic);
return strategy.GetResultantText();
}
public static byte[] GetContentBytesForPageStream(PdfReader reader, int pageNumber, int streamNumber) {
PdfDictionary pageDictionary = reader.GetPageN(pageNum);
PdfObject contentObject = pageDictionary.Get(PdfName.CONTENTS);
if (contentObject == null)
return new byte[0];
byte[] contentBytes = GetContentBytesFromContentObject(contentObject, streamNumber);
return contentBytes;
}
public static byte[] GetContentBytesFromContentObject(PdfObject contentObject, int streamNumber) {
// copy-paste logic from
// ContentByteUtils.GetContentBytesFromContentObject(contentObject);
// but in case PdfObject.ARRAY: only select the streamNumber you require
}
If you're specifically looking to just use PdfTextExtractor or PdfReaderContentParser, and ask the returned TextRenderInfo for the layer it's on, then I'm not sure it will be easily possible. There are a number of problems with that:
TextRenderInfo doesn't store that information, so you'd have to subclass it (which is possible)
you'd have to rewrite the logic that creates the TextRenderInfo objects. This is possible by registering custom IContentOperator objects for all text operators (Tj, TJ, ' and ") with the PdfTextExtractor or PdfReaderContentParser
the hardest part is that you have already lost layer information in ContentByteUtils.GetContentBytesFromContentObject - so you'd need to retain that somehow, which creates its own set of problems.
I'm trying to manipulate image resources in some PDF files; the workflow is: extract image resources -> process each -> replace old ones with the new.
Simple task really, I have working code for extracting and replacing, but when I replace, the new file size is nearly twice the original.
To replace the images, I use PDResources.put(COSName, PDXObject). Any ideas what would cause the size increase in the resulting document? It happens even if I completely omit the middle step in the workflow to process each image resource.
public static void PDFBoxReplaceImages() throws Exception {
PDDocument document = PDDocument.load(new File("C:\\Users\\Markus\\workspace\\pdf-test\\book.pdf"));
PDPageTree list = document.getPages();
for (PDPage page : list) {
PDResources pdResources = page.getResources();
for (COSName c : pdResources.getXObjectNames()) {
PDXObject o = pdResources.getXObject(c);
if (o instanceof PDImageXObject) {
counter++;
String path = "C:\\Users\\Markus\\workspace\\pdf-test\\images\\"+counter+".png";
PDImageXObject newImg =
PDImageXObject.createFromFile(path, document);
pdResources.put(c, newImg);
}
}
}
document.save("C:\\Users\\Markus\\workspace\\pdf-test\\book.pdf");
}
I used a extended version of LocationTextExtractionStrategy to extract connected texts of a pdf and their positions/sizes. I did this by using the locationalResult. This worked well until I tested a pdf containing texts with a different font (ttf). Suddenly these texts are splitted into single characters or small fragments.
For example "Detail" is not any more one object within the locationalResult list but splitted into six items (D, e, t, a, i, l)
I tried using the HorizontalTextExtractionStrategy by making the getLocationalResult method public:
public List<TextChunk> GetLocationalResult()
{
return (List<TextChunk>)locationalResultField.GetValue(this);
}
and using the PdfReaderContentParser to extract the texts:
reader = new PdfReader("some_pdf");
PdfReaderContentParser parser = new PdfReaderContentParser(reader);
var strategy = parser.ProcessContent(i, HorizontalTextExtractionStrategy());
foreach (HorizontalTextExtractionStrategy.HorizontalTextChunk chunk in strategy.GetLocationalResult())
{
// Do something with the chunk
}
but this also returns the same result.
Is there any other way to extract connected texts from a pdf?
I used a extended version of LocationTextExtractionStrategy to extract connected texts of a pdf and their positions/sizes. I did this by using the locationalResult. This worked well until I tested a pdf containing texts with a different font (ttf). Suddenly these texts are splitted into single characters or small fragments.
This problem is due to wrong expectations concerning the contents of the LocationTextExtractionStrategy.locationalResult private list member variable.
This list of TextChunk instances contains the pieces of text as they were forwarded to the strategy from the parsing framework (or probably as they were preprocessed by some filter class), and the framework forwards each single string it encounters in a content stream separately.
Thus, if a seemingly connected word in the content stream actually is drawn using multiple strings, you get multiple TextChunk instances for it.
There actually is some "intelligence" in the method getResultantText joining these chunks properly, adding a space where necessary and so on.
In case of your document, "DETAIL " usually is drawn like this:
[<0027> -0.2<00280037> 0.2<0024002c> 0.2<002f> -0.2<0003>] TJ
As you see there are slight text insertion point moves between 'D' and 'E', 'T' and 'A', 'I' and 'L', and 'L' and ' '. (Such mini moves usually represent kerning.) Thus, you'll get individual TextChunk instances for 'D', 'ET', 'AI', and 'L '.
Admittedly, the LocationTextExtractionStrategy.locationalResult member is not very well documented; but as it is a private member, this IMHO is forgivable.
That this worked well for many documents is due to many PDF creators not applying kerning and simply drawing connected text using single string objects.
The HorizontalTextExtractionStrategy is derived from the LocationTextExtractionStrategy and mainly differs from it in the way it arranges the TextChunk instances to a single string. Thus, you'll see the same fragmentation here.
Is there any other way to extract connected texts from a pdf?
If you want "connected texts" as in "atomic string objects in the content stream", you already have them.
If you want "connected texts" as in "visually connected texts, no matter where the constituent letters are drawn in the content stream", you have to glue those TextChunk instances together like the LocationTextExtractionStrategy and HorizontalTextExtractionStrategy do in getResultantText in combination with the comparison methods in their respective TextChunkLocationDefaultImp and HorizontalTextChunkLocation implementations.
After debugging deep into the iTextSharp library I figured out that my texts are drawn with the TJ operator as mkl also mentioned.
[<0027> -0.2<00280037> 0.2<0024002c> 0.2<002f> -0.2<0003>] TJ
iText processes these texts not as a single PdfString but as an array of PdfObjects which ends up in calling renderListener.RenderText(renderInfo) for each PdfString item in it (see ShowTextArray class and DisplayPdfString method). In the RenderText method however the information about the relation of the pdf strings within the array got lost and every item is added to locationalResult as an independent object.
As my goal is to extract the "argument of a single text drawing instruction" I extended the PdfContentStreamProcessor class about a new method ProcessTexts which returns a list of these atomic strings. My workaround is not very pretty as I had to copy paste some private fields and methods from the original source but it works for me.
class PdfContentStreamProcessorEx : PdfContentStreamProcessor
{
private IDictionary<int, CMapAwareDocumentFont> cachedFonts = new Dictionary<int, CMapAwareDocumentFont>();
private ResourceDictionary resources = new ResourceDictionary();
private CMapAwareDocumentFont font = null;
public PdfContentStreamProcessorEx(IRenderListener renderListener) : base(renderListener)
{
}
public List<string> ProcessTexts(byte[] contentBytes, PdfDictionary resources)
{
this.resources.Push(resources);
var texts = new List<string>();
PRTokeniser tokeniser = new PRTokeniser(new RandomAccessFileOrArray(new RandomAccessSourceFactory().CreateSource(contentBytes)));
PdfContentParser ps = new PdfContentParser(tokeniser);
List<PdfObject> operands = new List<PdfObject>();
while (ps.Parse(operands).Count > 0)
{
PdfLiteral oper = (PdfLiteral)operands[operands.Count - 1];
if ("Tj".Equals(oper.ToString()))
{
texts.Add(getText((PdfString)operands[0]));
}
else if ("TJ".Equals(oper.ToString()))
{
string text = string.Empty;
foreach (PdfObject entryObj in (PdfArray)operands[0])
{
if (entryObj is PdfString)
{
text += getText((PdfString)entryObj);
}
}
texts.Add(text);
}
else if ("Tf".Equals(oper.ToString()))
{
PdfName fontResourceName = (PdfName)operands[0];
float size = ((PdfNumber)operands[1]).FloatValue;
PdfDictionary fontsDictionary = resources.GetAsDict(PdfName.FONT);
CMapAwareDocumentFont _font;
PdfObject fontObject = fontsDictionary.Get(fontResourceName);
if (fontObject is PdfDictionary)
_font = GetFont((PdfDictionary)fontObject);
else
_font = GetFont((PRIndirectReference)fontObject);
font = _font;
}
}
this.resources.Pop();
return texts;
}
string getText(PdfString #in)
{
byte[] bytes = #in.GetBytes();
return font.Decode(bytes, 0, bytes.Length);
}
private CMapAwareDocumentFont GetFont(PRIndirectReference ind)
{
CMapAwareDocumentFont font;
cachedFonts.TryGetValue(ind.Number, out font);
if (font == null)
{
font = new CMapAwareDocumentFont(ind);
cachedFonts[ind.Number] = font;
}
return font;
}
private CMapAwareDocumentFont GetFont(PdfDictionary fontResource)
{
return new CMapAwareDocumentFont(fontResource);
}
private class ResourceDictionary : PdfDictionary
{
private IList<PdfDictionary> resourcesStack = new List<PdfDictionary>();
virtual public void Push(PdfDictionary resources)
{
resourcesStack.Add(resources);
}
virtual public void Pop()
{
resourcesStack.RemoveAt(resourcesStack.Count - 1);
}
public override PdfObject GetDirectObject(PdfName key)
{
for (int i = resourcesStack.Count - 1; i >= 0; i--)
{
PdfDictionary subResource = resourcesStack[i];
if (subResource != null)
{
PdfObject obj = subResource.GetDirectObject(key);
if (obj != null) return obj;
}
}
return base.GetDirectObject(key); // shouldn't be necessary, but just in case we've done something crazy
}
}
}
Please help me understand if my solution is correct.
I'm trying to extract text from a PDF file with a LocationTextExtractionStrategy parser. I'm getting exceptions because the ParseContentMethod tries to parse inline images? The code is simple and looks similar to this:
RenderFilter[] filter = { new RegionTextRenderFilter(cropBox) };
ITextExtractionStrategy strategy = new FilteredTextRenderListener(new LocationTextExtractionStrategy(), filter);
PdfTextExtractor.GetTextFromPage(pdfReader, pageNumber, strategy);
I realize the images are in the content stream but I have a PDF file failing to extract text because of inline images. It returns an UnsupportedPdfException of "The filter /DCTDECODE is not supported" and then it finally fails with and InlineImageParseException of "Could not find image data or EI", when all I really care about is the text. The BI/EI exists in my file so I assume this failure is because of the /DCTDECODE exception. But again, I don't care about images, I'm looking for text.
My current solution for this is to add a filterHandler in the InlineImageUtils class that assigns the Filter_DoNothing() filter to the DCTDECODE filterHandler dictionary. This way I don't get exceptions when I have InlineImages with DCTDECODE. Like this:
private static bool InlineImageStreamBytesAreComplete(byte[] samples, PdfDictionary imageDictionary) {
try {
IDictionary<PdfName, FilterHandlers.IFilterHandler> handlers = new Dictionary<PdfName, FilterHandlers.IFilterHandler>(FilterHandlers.GetDefaultFilterHandlers());
handlers[PdfName.DCTDECODE] = new Filter_DoNothing();
PdfReader.DecodeBytes(samples, imageDictionary, handlers);
return true;
} catch (IOException e) {
return false;
}
}
public class Filter_DoNothing : FilterHandlers.IFilterHandler
{
public byte[] Decode(byte[] b, PdfName filterName, PdfObject decodeParams, PdfDictionary streamDictionary)
{
return b;
}
}
My problem with this "fix" is that I had to change the iTextSharp library. I'd rather not do that so I can try to stay compatible with future versions.
Here's the PDF in question:
https://app.box.com/s/7eaewzu4mnby9ogpl2frzjswgqxn9rz5