Develop Reference

does vaadin video component support preload attribute

I have more than 10 mp4 videos which I am tying to embed in my web application using vaadin video component. When I run my application on Edge/IE the vidoes work fine, but on chrome they dont. Its known issue with chrome where if the page has more than 6-8 mp4 videos, it hangs as it tried to preload all of them together.
I was wondering if the video component provide me option to set the preload to none. I can see the mediabase has this option
https://vaadin.com/api/7.6.7/index.html?com/google/gwt/media/client/MediaBase.html
But I dont see it for video.
Also I found another link where they seems to do the fix https://github.com/vaadin/framework/issues/5178 , but couldnt make it work.
Any help?

Until the commit/PR in your linkgets merged, it does not in 7 or 8.
However, you can use an AbstractExtension and AbstractExtensionConnector to accomplish this.
The AbstractExtension
package com.my.package;
import com.vaadin.server.AbstractClientConnector;
import com.vaadin.server.AbstractExtension;
import com.vaadin.ui.AbstractComponent;
public class VideoPreloadExtension extends AbstractExtension {
public VideoPreloadExtension() {
}
public VideoPreloadExtension(AbstractClientConnector target) {
super(target);
}
public void extend(AbstractComponent component) {
super.extend(component);
}
}
The AbstractExtensionConnector
package com.my.package.client;
import com.google.gwt.user.client.ui.Widget;
import com.vaadin.client.ComponentConnector;
import com.vaadin.client.ServerConnector;
import com.vaadin.client.extensions.AbstractExtensionConnector;
import com.my.package.VideoPreloadExtension;
import com.vaadin.shared.ui.Connect;
#Connect(VideoPreloadExtension.class)
public class VideoPreloadConnector extends AbstractExtensionConnector {
#Override
protected void init() {
super.init();
}
#Override
protected void extend(ServerConnector target) {
// Get the extended widget
final Widget widget = ((ComponentConnector) target).getWidget();
widget.getElement().setAttribute("preload","auto");
}
}
Usage is as follows:
Video image = new Video();
VideoPreloadExtension ext = new VideoPreloadExtension();
ext.extend(image);
Some Notes (because vaadin can be a pain at times)
If you have a library module already, its best to add the above classes to it.
Confirm that the module you add these classes to has the following dependency add so the widgetset will get compiled:
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-client</artifactId>
</dependency>
Remember that the VideoPreloadConnector needs to be in a package name that ends with ".client".
Here is a screenshot of an inspect element from chrome of it working:
HTHs!

Taking photos from a website, and loading them in JavaFX

Right now I'm working on a GUI project, where I'm trying to take photos, found from the URLs I find from inside the source code of a website, and load them into my JavaFx GUI.
For example, I wish for Java to load the website http://www.imdb.com/movies-in-theaters/?ref_=nv_tp_inth_1, and collect all of the "cover photos"/thumbnails that you see as you scroll down the page (no matter the size of the image), and then load them into the GUI view (into an HBox full as a bunch of ImageViews for example).
More in-depth as well, eventually I would like to get it to the point, that the user could click on the image/imageview, and (again for example) it would show show the trailer for the selected movie. (My thinking, is that the trailer link would be found from website, if you clicked through and went to the next page, found the link, went to youtube, and removed all of the content except for the video player necessarily).
In the web-browser that I use, I have access see the page's HTML elements/design, and look through all of the source coding. After just a few twirls, I can easily find the direct URL to the thumbnail/image I'm looking for, and I've found that in javaFX I can load an image into my GUI as a URL, like so:
Image img = new Image("http://website/websiteSubPage/websiteImage");
ImageView imgView = new ImageView(img);
I've also found that the concept of what I'm looking for is called WebScraping... But all of the modules I've looked into and researched so far aren't helping with what I need. The closest module I've found so far, is HtmlUnit. However, HtmlUnit is all about web automation -- And I couldn't find anything in it's documentation on finding a photo, and loading it as a Java Image object, that is callable into an ImageView.
My best guess at the moment, is to have Java load the website in the background, gather the source code, and then I could create a String Manipulator of sorts, that would essentially just find, trim to, and load the URL of every image it finds, and put it into an HBox full of ImageViews.
Ultimately, I feel like my only solution looks something like this:
public HBox listView(){
HBox temp = new HBox();
// Load the website
// Load the source code into a large string.
for (int i=0; i>=<numberOfPhotosPreCalculatedSomeHow>;i++){
Image img = new Image( /*Manipulated string algorithm to find the next image URL*/);
ImageView imgView = new ImageView(img);
ImageView.setOnAction(e -> { /* load the trailer */ }; } // (Lambda)
temp.getChildren().add(ImageView);
}
return temp;
}
However, doing all of this... Makes me feel like I'm doing something horribly wrong, and I need some help.
Thoughts? Is there a module or plugin built specifically for this? Is this possible, or just dumb?

Found the answer!
There's built-in java methods that can allow me to scan in information from a website, and then decipher it as needed.
In my case, here's the code I used:
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Scanner;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class WebReader extends Application{
// Class variable to hold our found URLs :)
static ArrayList<String> listArray;
public static void main(String[] args) throws IOException {
// Gather page & URL data, and read it
String address = "http://reddit.com";
URL pageLocation = new URL(address);
Scanner in = new Scanner(pageLocation.openStream());
// Initialize an ArrayList to store all of our collected URLs
listArray = new ArrayList<String>();
// Decipher the code line by line
while (in.hasNext()) {
String line = in.next();
if (line.contains("href=\"http://")) {
int from = line.indexOf("\"");
int to = line.lastIndexOf("\"");
System.out.println(line.substring(from + 1, to));
listArray.add(line.substring(from + 1, to));
}
}
// Next, we implement into JavaFx
launch(args);
}
#Override
public void start(Stage primaryStage) {
primaryStage.setTitle("My loaded photos");
// Create a place to put our content
HBox content = new HBox();
ScrollPane scrollPane = new ScrollPane(content);
scrollPane.setFitToHeight(true);
System.out.println(listArray.size());
for (int i = 0; i <= listArray.size() - 1; i++) {
Image img = new Image(listArray.get(i));
ImageView imgView = new ImageView(img);
content.getChildren().add(imgView);
} // Launch and sail away!! :)
Scene s = new Scene(scrollPane, 800, 600);
primaryStage.setScene(s);
primaryStage.show();
}
}
So this was the solution that I was able to find-- I can't believe it took me so long to find a solution, but I hope this helps anybody who is on the same boat that I am. :)

How to convert SWT Image to data URI for use in Browser-widget

I am trying to display images inside a Browser-widget (SWT). These images can be found inside the a jar file (plug-in development). However: this is not directly possible as the browser-widget expects some kind of URL or URI information.
My idea is to turn SWT-images into data-URI values, which I could induce into the src-attribute of every given img-element. I know, that this is not a good solution from a performance point of view, but I don't mind the speed disadvantage.
I'd like to know how to turn a SWT image into a data-URI value for use in a browser-widget.
My code so far:
package editor.plugin.editors.htmlprevieweditor;
import editor.plugin.Activator;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;
public class HtmlPreview extends Composite implements DisposeListener {
private final Browser content;
public HtmlPreview(final Composite parent, final int style) {
super(parent, style);
this.setLayout(new FillLayout());
content = new Browser(this, style);
final ImageData imageData = Activator.getImageDescriptor(Activator.IMAGE_ID + Activator.PREVIEW_SMALL_ID).getImageData();
content.setText("<html><body><img src=\"data:image/png;base64," + imageData + "\"/></body></html>"); // need help on changing imageData to a base64-encoded String of bytes?
this.addDisposeListener(this);
}
#Override
public void widgetDisposed(final DisposeEvent e) {
e.widget.dispose();
}
}
Any help is greatly appreciated :)!
Edit 1: I have read SWT Image to/from String , but unfortunately it does not seem to exactly cover my needs.
Edit 2: I don't know if it matters, but I am trying to load a PNG24-image with per-pixel alpha-transparency.

The question is too general if you only say "Browser in SWT". Mozzila browser supports jar URL protocol, and you can do this:
public static void main(String[] args) {
final Display display = new Display();
final Shell shell = new Shell(display);
shell.setLayout(new FillLayout());
final URL url = ShellSnippet.class.getResource("/icons/full/message_error.gif");
final Browser browser = new Browser(shell, SWT.MOZILLA);
final String html = String.format("<html><head/><body>image: <img src=\"%s\"/></body></html>", url);
browser.setText(html);
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch()) {
display.sleep();
}
}
display.dispose();
}
It looks like this:
I used an image from the JFace jar to keep the snippet simple and yet work for most people out of the box. It is GIF, but I expect it to work just as well with PNG files.
If you use Internet Explorer, something I do not recommend because your application depends on OS version, this does not work. It looks like this (after changing in the snippet the style from SWT.MOZILLA to SWT.NONE):
It does however understand the file protocol and you can copy files to the temp folder and create URLs directly to the file using File.toURL(). This should work for any browser.
I cannot test the simple solution on WEBKIT broswer. If anyone can, please post the result in a comment.

How do you get rajawali to work (tutorial 1 on git)

I am quite new to android development, I know the basics activities, maps, sqlite, etc.
I would like to be able to implement some 3D objects to be able to interact with within my apps. After a bit of searching I found that rajawali seems to be the best method. As you do I started with the first tutorial and reading the source code from the example docs.
Where I have become lost is I have followed the tutorial word for word and and I cant run the application due to errors in the script. If anybody has used Rajawali before I would appreiate some pointers as to where I have gone wrong. (the tutorial was last updated 2 month ago so its quite recent). Tutorial
Here is my source code
MainActivity:
package rajawali.tutorials;
import rajawali.RajawaliActivity;
import android.os.Bundle;
import android.view.Menu;
public class MainActivity extends RajawaliActivity {
private Renderer mRenderer;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mRenderer = new Renderer(this);
mRenderer.setSurfaceView(mSurfaceView);
super.setRenderer(mRenderer);
}
}
Renderer:
package rajawali.tutorials;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import rajawali.lights.DirectionalLight;
import rajawali.materials.textures.ATexture.TextureException;
import rajawali.materials.textures.Texture;
import rajawali.primitives.Sphere;
import rajawali.renderer.RajawaliRenderer;
public class Renderer extends RajawaliRenderer {
private DirectionalLight mLight;
Sphere mSphere;
public Renderer(Context context) {
super(context);
setFrameRate(60);
}
public void initScene() {
mLight = new DirectionalLight(1f, 0.2f, -1.0f);
mLight.setColor(1.0f, 1.0f, 1.0f);
mLight.setPower(2);
try {
*DiffuseMaterial* material = new *DiffuseMaterial*(); //there is an error here (DiffuseMaterial cannot be rsolved as a type)
material.addTexture(new *Texture(R.drawable.earthtruecolor_nasa_big)*); //here (constructor Texture(int) cannot be defined)
mSphere = new Sphere(1, 24, 24);
mSphere.setMaterial(material);
mSphere.*addLight(mLight)*; //and here (The method addLight(DirectionalLight) is undefined for the type Sphere)
addChild(mSphere);
} catch (TextureException e) {
e.printStackTrace();
}
getCurrentCamera().setZ(4.2f);
}
#Override
public void onDrawFrame(GL10 glUnused) {
super.onDrawFrame(glUnused);
mSphere.setRotY(mSphere.getRotY() + 1);
}
}
I don't realy want to be spoon feed code if I can help it but it appears that the error is in the 'DiffuseMaterial'. Why is this or is there a better way of manipulating 3D objects other than using min3D or Rajawali?

I also have been trying to run this rajawali tutorial using next code.
Class RajawaliTutorialActivity
package rajawali.tutorials;
import rajawali.RajawaliActivity;
import android.os.Bundle;
public class RajawaliTutorialActivity extends RajawaliActivity {
public RajawaliTutorialRenderer mRenderer;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mRenderer = new RajawaliTutorialRenderer(this);
mRenderer.setSurfaceView(mSurfaceView);
super.setRenderer(mRenderer);
}
}
Class RajawaliTutorialRenderer
package rajawali.tutorials;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import rajawali.Camera;
import rajawali.Object3D;
import rajawali.lights.DirectionalLight;
import rajawali.materials.Material;
import rajawali.materials.textures.ATexture.TextureException;
import rajawali.materials.textures.Texture;
import rajawali.primitives.Sphere;
import rajawali.renderer.RajawaliRenderer;
public class RajawaliTutorialRenderer extends RajawaliRenderer {
public DirectionalLight light;
public Object3D sphere;
public Context context;
public Camera camera;
public RajawaliTutorialRenderer(Context context) {
super(context);
this.context = context;
setFrameRate(60);
}
public void initScene() {
light = new DirectionalLight(1f, 0.2f, -1.0f); // set the direction
light.setColor(1.0f, 1.0f, 1.0f);
light.setPower(2);
try{
Material material = new Material();
material.addTexture(new Texture("earthColors", R.drawable.earthtruecolor_nasa_big));
material.setColorInfluence(0);
sphere = new Sphere(1, 24, 24);
sphere.setMaterial(material);
getCurrentScene().addLight(light);
super.addChild(sphere);
} catch (TextureException e){
e.printStackTrace();
}
getCurrentCamera().setZ(4.2f);
}
#Override
public void onDrawFrame(GL10 glUnused) {
super.onDrawFrame(glUnused);
sphere.setRotY(sphere.getRotY() + 1);
}
}
See that changes are:
declare sphere object as Object3D instead Sphere.
change DiffuseMaterial by Material for material declaration.
change parameters to get Texture. First parameter is an custom identifier and second parameter is the resource id.
add the line material.setColorInfluence(0); after load texture, if this line isn't added, the "heart" becomes red (I'm not sure why).
replace sphere object by scene object (accessing with getCurrentScene method) to call addLight method.
Add try/catch for line material.addTexture() as this method now throws a TextureException
add getCurrentCamera().setZ(4.2f); to the end of initScene

It looks like this has to do with the version of Rajawali.
On this page it says not to use the master branch:
Whether you choose to clone or download, you probably will want to use one of the release tags. The master branch of both the library and examples is used for development and should be considered unstable for production code. When we release a stable version, it will be tagged. If you are cloning, you can simply checkout a tag.
If you cloned Rajawali using git, you'll want to checkout from a tag. To list the tags:
$ git tag
v0.9
At the time of writing, v0.9 is your only choice.
$ git checkout v0.9
Now you'll have DiffuseMaterial available. However, some of the other classes are still missing.
EDIT:
It looks like this tutorial neither applies to v0.9 nor the latest master branch. I made a working version of tutorial 1, which you can find linked here.

You can also use the RajawaliExamples application I wrote, which is composed of contributed examples, as a demonstration of using the master branch.
https://github.com/MasDennis/RajawaliExamples
Also to clarify on Deans quote, the statement made there is dissuade people from freaking out when the API changed underneath them which was mostly relevant when jwoolston was making large changes to support scene graphs. The bulk of that work is done and if ever finished, the api is likely to change significantly from its current state as the other major items are already complete. Such items are pieces like animation, more parsing options, flexible rendering, etc.

I want to display a blurred image in imageJ. Why doesn't this work?

I'm very very new to imageJ but know a little Java.
Essentially I want to open a file from an OpenDialog display the image, then blur the image and display the resulting blurred image. My program compiles, however the two images look the same. Can anybody help? How do I make the program display a blurred and unblurred image?
import ij.*;
import ij.io.*;
import ij.process.*;
import ij.gui.*;
import java.awt.*;
import ij.plugin.*;
import java.util.*;
import java.io.*;
public class opens_ implements PlugIn {
ImagePlus imp;
public void run(String arg){
OpenDialog od = new OpenDialog("Open.....", arg);
Opener op = new Opener();
String directory = od.getDirectory();
String filename = od.getFileName();
if (filename==null) return ;
imp = op.openImage(directory, filename);
imp.show();
ImageProcessor improc = imp.getProcessor();
improc.smooth();
ImagePlus alter = new ImagePlus("alter", improc) ;
alter.show();
}
}
Thanks
Bateman

When you call .smooth() on improc, that call alters the image data contained by the ImageProcessor, which is being displayed by the original ImagePlus. Then you create a new ImagePlus based on the same ImageProcessor, so of course it's the blurred image rather than the original. If you don't want the original to be altered, then you can duplicate the ImageProcessor before smoothing, for example by changing the line:
ImageProcessor improc = imp.getProcessor();
... to:
ImageProcessor improc = imp.getProcessor().duplicate();
Update: when I tested your code, I saw both images as blurred. If you still see the original images, try adding the following to the end of your run method:
imp.updateAndDraw()
alter.updateAndDraw()