RE: Outputting intrinsic dimension info of images
This is good stuff! I did some modifications to your code to make it work with
our way of retrieving images from the database and it works as a charm!
Thank you!
-Original Message-
From: Jeremias Maerki [mailto:d...@jeremias-maerki.ch]
Sent: Tuesday, July 26, 2011 3:07 PM
To: fop-users@xmlgraphics.apache.org
Subject: Re: Outputting intrinsic dimension info of images
No, I don't think there's an easy way to find out how much FOP scales
the image. You could look in one of the immediate formats but that only
gets you the target size but not the original size.
I found some code I wrote some time ago which is a Xalan-J extension
that does basically what you need (except share the image manager with
FOP):
import java.io.File;
import java.io.IOException;
import java.lang.ref.SoftReference;
import java.net.URI;
import java.net.URISyntaxException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Source;
import javax.xml.transform.TransformerException;
import javax.xml.transform.URIResolver;
import javax.xml.transform.stream.StreamSource;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.apache.xalan.extensions.ExpressionContext;
import org.apache.xml.utils.QName;
import org.apache.xmlgraphics.image.loader.ImageContext;
import org.apache.xmlgraphics.image.loader.ImageException;
import org.apache.xmlgraphics.image.loader.ImageInfo;
import org.apache.xmlgraphics.image.loader.ImageManager;
import org.apache.xmlgraphics.image.loader.ImageSessionContext;
import org.apache.xmlgraphics.image.loader.ImageSize;
import org.apache.xmlgraphics.image.loader.impl.AbstractImageSessionContext;
import org.apache.xmlgraphics.image.loader.impl.DefaultImageContext;
public class ImageExtension {
private static SoftReferenceImageManager imageManagerRef = null;
/**
* Returns a document fragment with information on the given image.
* @param context the expression context
* @param uri the image URI
* @param baseUri the optional base URI for resolving relative URIs
* @return the image information
* @throws IOException if an I/O error occurs
* @throws ParserConfigurationException Problems creating a DocumentBuilder
* @throws ImageException Failure to load the image
*/
public static Node imageInfo(final ExpressionContext context, final String
uri)
throws IOException, ParserConfigurationException,
ImageException {
return imageInfo(context, uri, null);
}
/**
* Returns a document fragment with information on the given image.
* @param context the expression context
* @param uri the image URI
* @param baseUri the optional base URI for resolving relative URIs
* @return the image information
* @throws IOException if an I/O error occurs
* @throws ParserConfigurationException Problems creating a DocumentBuilder
* @throws ImageException Failure to load the image
*/
public static Node imageInfo(final ExpressionContext context, final String
uri,
final String baseUri)
throws IOException, ParserConfigurationException,
ImageException {
final ImageManager imageManager = getImageManager();
ImageSessionContext sessionContext = new AbstractImageSessionContext() {
public float getTargetResolution() {
return 300; //dpi
}
public ImageContext getParentContext() {
return imageManager.getImageContext();
}
@Override
protected Source resolveURI(String uri) {
//TODO Improve resolution with xml:base etc.
try {
String base = baseUri;
if (base == null || base.length() == 0) {
base = context.getVariableOrParam(new
QName(resource-base)).str();
}
URIResolver resolver =
context.getXPathContext().getURIResolver();
if (resolver != null) {
//System.out.println(Resolving: + uri + , + base);
return resolver.resolve(uri, base);
} else {
URI b;
try {
b = new URI(base);
} catch (URISyntaxException use) {
File f = new File(base);
b = f.toURI();
}
URI fileURI;
try {
fileURI = new URI(uri);
} catch (URISyntaxException use) {
File f = new File(uri);
fileURI = f.toURI();
}
URI resolved = b.resolve(fileURI
Outputting intrinsic dimension info of images
Hi, I'm using fo:external-graphic to include images in the pdf. Is there any way that I can find out the intrinsic width and height of an image? So that I can include that information in the resulting pdf. Thanks //Erik
Re: Outputting intrinsic dimension info of images
What type if images are you using? On unix, the 'file' command on .png files gives the dimension. For tiff I use tiff-info. On 07/26/2011 10:42 AM, Erik Wiklander wrote: Hi, I'm using fo:external-graphic to include images in the pdf. Is there any way that I can find out the intrinsic width and height of an image? So that I can include that information in the resulting pdf. Thanks //Erik
Re: Outputting intrinsic dimension info of images
Erik, you can preload the image using the XML Graphics Commons image loading framework (which FOP uses, too): http://xmlgraphics.apache.org/commons/image-loader.html#preloading The ImageInfo object will then contain the intrinsic size. You can use the ImageManager from the FopFactory and probably re-use the ImageSessionContext from the FOUserAgent: ImageManager imageManager = fopFactory.getImageManager(); ImageSessionContext imageSessionContext = foUserAgent.getImageSessionContext(); This allows you to profit from the image cache. What you do with the values and where exactly you want to write it in the PDF is a different question. I don't know what you have in mind here. Do you want to print the values on the page along with the image? Sounds like an XSLT extension then. On 26.07.2011 18:42:15 Erik Wiklander wrote: Hi, I'm using fo:external-graphic to include images in the pdf. Is there any way that I can find out the intrinsic width and height of an image? So that I can include that information in the resulting pdf. Thanks //Erik Jeremias Maerki - To unsubscribe, e-mail: fop-users-unsubscr...@xmlgraphics.apache.org For additional commands, e-mail: fop-users-h...@xmlgraphics.apache.org
RE: Outputting intrinsic dimension info of images
Ok, thanks for the reply! This is the background to my question: I'm working on an application where we have an image markup tool that lets the user put a message somewhere on the image. The message is stored together with the coordinates of where on the image it is placed. Now, when we run the report, I want the message to be displayed on top of the image in the correct place. I want this to work even if the picture has been scaled down to fit the paper. To place the text on the correct place, I have to compare the intrinsic dimensions of the image with the fixed dimensions of the image in the report, to correctly place the message on top. I currently have a working solution for this, but it is not very good from a performance perspective: Before running the report I download the image and get the dimensions using Sanselan and I send these dimensions to the report. If I could profit from the image cache, that would of course be great. But I'm not really sure how I could write my own extension to do this. Another solution to my problem would be if I somehow could find out by how much the image was scaled. Is that possible to find out? (In a simple way :) -Original Message- From: Jeremias Maerki [mailto:d...@jeremias-maerki.ch] Sent: Tuesday, July 26, 2011 1:09 PM To: fop-users@xmlgraphics.apache.org Subject: Re: Outputting intrinsic dimension info of images Erik, you can preload the image using the XML Graphics Commons image loading framework (which FOP uses, too): http://xmlgraphics.apache.org/commons/image-loader.html#preloading The ImageInfo object will then contain the intrinsic size. You can use the ImageManager from the FopFactory and probably re-use the ImageSessionContext from the FOUserAgent: ImageManager imageManager = fopFactory.getImageManager(); ImageSessionContext imageSessionContext = foUserAgent.getImageSessionContext(); This allows you to profit from the image cache. What you do with the values and where exactly you want to write it in the PDF is a different question. I don't know what you have in mind here. Do you want to print the values on the page along with the image? Sounds like an XSLT extension then. On 26.07.2011 18:42:15 Erik Wiklander wrote: Hi, I'm using fo:external-graphic to include images in the pdf. Is there any way that I can find out the intrinsic width and height of an image? So that I can include that information in the resulting pdf. Thanks //Erik Jeremias Maerki - To unsubscribe, e-mail: fop-users-unsubscr...@xmlgraphics.apache.org For additional commands, e-mail: fop-users-h...@xmlgraphics.apache.org - To unsubscribe, e-mail: fop-users-unsubscr...@xmlgraphics.apache.org For additional commands, e-mail: fop-users-h...@xmlgraphics.apache.org
Re: Outputting intrinsic dimension info of images
(resolved.toASCIIString());
}
return src;
}
} catch (TransformerException te) {
try {
context.getErrorListener().warning(te);
} catch (TransformerException e) {
//ignore
}
return null; //Fail
}
}
};
ImageInfo info = imageManager.getImageInfo(uri, sessionContext);
return toNode(info);
}
private static Node toNode(ImageInfo info) throws
ParserConfigurationException {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(false);
dbf.setValidating(false);
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.newDocument();
Element imageInfo = doc.createElement(image-info);
doc.appendChild(imageInfo);
imageInfo.setAttribute(uri, info.getOriginalURI());
imageInfo.setAttribute(format, info.getMimeType());
Element imageSize = doc.createElement(size);
imageInfo.appendChild(imageSize);
ImageSize size = info.getSize();
imageSize.setAttribute(width-mpt,
Integer.toString(size.getWidthMpt()));
imageSize.setAttribute(height-mpt,
Integer.toString(size.getHeightMpt()));
imageSize.setAttribute(width-px, Integer.toString(size.getWidthPx()));
imageSize.setAttribute(height-px,
Integer.toString(size.getHeightPx()));
imageSize.setAttribute(resolution-horz,
Double.toString(size.getDpiHorizontal()));
imageSize.setAttribute(resolution-vert,
Double.toString(size.getDpiVertical()));
return imageInfo;
}
private static ImageManager getImageManager() {
ImageManager imageManager = null;
if (imageManagerRef != null) {
imageManager = imageManagerRef.get();
}
if (imageManager == null) {
imageManager = new ImageManager(new DefaultImageContext());
imageManagerRef = new SoftReferenceImageManager(imageManager);
}
return imageManager;
}
}
Integration in the stylesheet:
xmlns:img=packagename for extension.ImageExtension
exclude-result-prefixes=img
t:variable name=image-info select=img:image-info({@href})/
XPath to access the width: $image-info/size/@width-mpt
More info: http://xml.apache.org/xalan-j/extensions.html
On 26.07.2011 20:50:09 Erik Wiklander wrote:
Ok, thanks for the reply!
This is the background to my question:
I'm working on an application where we have an image markup tool that lets
the user put a message somewhere on the image. The message is stored together
with the coordinates of where on the image it is placed.
Now, when we run the report, I want the message to be displayed on top of the
image in the correct place. I want this to work even if the picture has been
scaled down to fit the paper.
To place the text on the correct place, I have to compare the intrinsic
dimensions of the image with the fixed dimensions of the image in the report,
to correctly place the message on top.
I currently have a working solution for this, but it is not very good from a
performance perspective: Before running the report I download the image and
get the dimensions using Sanselan and I send these dimensions to the report.
If I could profit from the image cache, that would of course be great. But
I'm not really sure how I could write my own extension to do this.
Another solution to my problem would be if I somehow could find out by how
much the image was scaled. Is that possible to find out? (In a simple way :)
-Original Message-
From: Jeremias Maerki [mailto:d...@jeremias-maerki.ch]
Sent: Tuesday, July 26, 2011 1:09 PM
To: fop-users@xmlgraphics.apache.org
Subject: Re: Outputting intrinsic dimension info of images
Erik,
you can preload the image using the XML Graphics Commons image loading
framework (which FOP uses, too):
http://xmlgraphics.apache.org/commons/image-loader.html#preloading
The ImageInfo object will then contain the intrinsic size. You can use
the ImageManager from the FopFactory and probably re-use the
ImageSessionContext from the FOUserAgent:
ImageManager imageManager = fopFactory.getImageManager();
ImageSessionContext imageSessionContext =
foUserAgent.getImageSessionContext();
This allows you to profit from the image cache.
What you do with the values and where exactly you want to write it in
the PDF is a different question. I don't know what you have in mind here.
Do you want to print the values on the page along with the image? Sounds
like an XSLT extension then.
On 26.07.2011 18:42:15 Erik Wiklander wrote:
Hi,
I'm using fo:external-graphic to include images in the pdf. Is there
any way that I can find out the intrinsic width and height of an image? So
that I can include
