I want to get image dpi to convert pixels to cm, so I use ImageInfo.java to get this:
ImageInfo myMapInfo = new ImageInfo();
try {
File testFile = new File(fileNameString);
InputStream myMapStream = new FileInputStream(testFile);
myMapInfo.setInput(myMapStream);
myMapInfo.setDetermineImageNumber(true);
myMapInfo.setCollectComments(true);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
x = myMapInfo.getPhysicalWidthInch();
y = myMapInfo.getPhysicalHeightInch();
but unfortunately I get -1 and -1 in (x, y)! I use this class:
ImageInfo.java
From looking at the source code of ImageInfo, you need to call the check() method of your myMapInfo variable and if this passes you can use the various getXxX() methods to obtain whatever information you need. Incidentally getting -1 as result means information is not available, but that's most likely cause you're not invoking the check() method.
Related
In fact I am making a Minecraft plugin and I was wondering how some plugins (without using DB) manage to keep information even when the server is off.
For example if we make a grade plugin and we create a different list or we stack the players who constitute each. When the server will shut down and restart afterwards, the lists will become empty again (as I initialized them).
So I wanted to know if anyone had any idea how to keep this information.
If a plugin want to save informations only for itself, and it don't need to make it accessible from another way (a PHP website for example), you can use YAML format.
Create the config file :
File usersFile = new File(plugin.getDataFolder(), "user-data.yml");
if(!usersFile.exists()) { // don't exist
usersFile.createNewFile();
// OR you can copy file, but the plugin should contains a default file
/*try (InputStream in = plugin.getResource("user-data.yml");
OutputStream out = new FileOutputStream(usersFile)) {
ByteStreams.copy(in, out);
} catch (Exception e) {
e.printStackTrace();
}*/
}
Load the file as Yaml content :
YamlConfiguration config = YamlConfiguration.loadConfiguration(usersFile);
Edit content :
config.set(playerUUID, myVar);
Save content :
config.save(usersFile);
Also, I suggest you to make I/O async (read & write) with scheduler.
Bonus:
If you want to make ONE config file per user, and with default config, do like that :
File oneUsersFile = new File(plugin.getDataFolder(), playerUUID + ".yml");
if(!oneUsersFile.exists()) { // don't exist
try (InputStream in = plugin.getResource("my-def-file.yml");
OutputStream out = new FileOutputStream(oneUsersFile)) {
ByteStreams.copy(in, out); // copy default to current
} catch (Exception e) {
e.printStackTrace();
}
}
YamlConfiguration userConfig = YamlConfiguration.loadConfiguration(oneUsersFile);
PS: the variable plugin is the instance of your plugin, i.e. the class which extends "JavaPlugin".
You can use PersistentDataContainers:
To read data from a player, use
PersistentDataContainer p = player.getPersistentDataContainer();
int blocksBroken = p.get(new NamespacedKey(plugin, "blocks_broken"), PersistentDataType.INTEGER); // You can also use DOUBLE, STRING, etc.
The Namespaced key refers to the name or pointer to the data being stored. The PersistentDataType refers to the type of data that is being stored, which can be any Java primitive type or String. To write data to a player, use
p.set(new NamespacedKey(plugin, "blocks_broken"), PersistentDataType.INTEGER, blocksBroken + 1);
I'm trying to use ImageJ2 directly from Java to create a binarised image coming from an input image.
A somewhat working version of my code looks like this:
final File file = new File("input.png");
try {
DefaultDataTypeService dataTypeService = new DefaultDataTypeService();
Dataset dataset = imageJ.dataset().open(file.getAbsolutePath());
Img inputImg = dataset.getImgPlus();
PluginInfo pluginInfo = imageJ.plugin().getPlugin(Binarize.class);
Binarize binarizeOp = (Binarize) pluginInfo.createInstance();
binarizeOp.setContext(imageJ.getContext());
binarizeOp.setChangeInput(true);
binarizeOp.setFillMaskBackground(true);
binarizeOp.setFillMaskForeground(true);
binarizeOp.setInputData(dataset);
binarizeOp.setInputMask(null);
binarizeOp.setMaskColor(Binarize.WHITE);
binarizeOp.setMaskPixels(Binarize.INSIDE);
binarizeOp.setThresholdEachPlane(false);
binarizeOp.setDefaultThresholdMethod();
binarizeOp.run();
dataset.rgbChange();
DefaultDatasetService defaultDatasetService = new DefaultDatasetService();
Img outputImg = dataset.getImgPlus();
outputImg = outputImg.factory().imgFactory(new UnsignedByteType()).create(outputImg,new UnsignedByteType());
Dataset outputDataset = defaultDatasetService.create(outputImg);
imageJ.dataset().save(outputDataset,"input_binary.png");
} catch (IOException e) {
e.printStackTrace();
} catch (InstantiableException e) {
e.printStackTrace();
} catch (IncompatibleTypeException e) {
e.printStackTrace();
}
Running this code I have the problem that "input_binary.png" will be completely black, a behaviour I can reproduce using the ImageJ client application.
What I need to do in the client is to change the image type from "8-bit Color" to "RGB-Color". But I can not figure out how to reproduce that in Java using the current version of the net.imagej library.
I know that it would be possible using the 1.x library but I would like to to it using the 2.x.
Any help would be greatly appreciated.
You're getting black images because of this:
outputImg = outputImg.factory().imgFactory(new UnsignedByteType()).create(outputImg,new UnsignedByteType());
Which is just copying the dimensionality of your source image, not its values.
A few other key points:
It's best practice to have your Contextual objects (e.g. Services) derived from the Context instead of manually constructed.
The Binarize command has a Dataset output so it's not necessary to go Dataset > ImgPlus > Dataset
If you do want to write the dataset out you need to convert from the BitType output by Binarize to one that's supported.
See below for an example of running Binarize, getting the output, converting it and writing it out. Hope that helps!
public static void main(String... args) {
final File file = new File("inpath.png");
final File out = new File("outpath.png");
// This is just sugar for the point of illustration.
// The purpose here is just to have access to a Context
ImageJ imagej = new ImageJ();
// Cache the context for future use.
Context context = imagej.getContext();
try {
// Use the context to get the services we want to ensure they are all
// properly initialized.
// If this was a Command these could all be #Parameters to be populated
// automatically.
DatasetService datasetService = context.getService(DatasetService.class);
CommandService commandService = context.getService(CommandService.class);
DatasetIOService datasetIOService =
context.getService(DatasetIOService.class);
Dataset input = datasetIOService.open(file.getAbsolutePath());
// Start the command
Future<CommandModule> future =
commandService.run(Binarize.class, true, "inputData", input);
// Get the command output
Dataset binarized = (Dataset) future.get().getOutput("outputMask");
// The output type is a binary image which, at the moment, needs to be
// explicitly converted to something that can be written out.
// Adapted from:
// http://fiji.sc/ImgLib2_Examples#Example_2c_-_Generic_copying_of_image_data
Img inputImg = input.getImgPlus().getImg();
Img outputImg = binarized.getImgPlus().getImg();
Img typedImg =
inputImg.factory().create(inputImg, inputImg.firstElement());
scale(outputImg, typedImg);
Dataset output = datasetService.create(typedImg);
// Save the output dataset
datasetIOService.save(output, out.getAbsolutePath());
}
catch (IOException exc) {
exc.printStackTrace();
}
catch (InterruptedException exc) {
exc.printStackTrace();
}
catch (ExecutionException exc) {
exc.printStackTrace();
}
finally {
// Dispose of the context to shut down
context.dispose();
}
}
public static <T extends IntegerType<T>> void scale(
final RandomAccessible<BitType> source, final IterableInterval<T> target)
{
// create a cursor that automatically localizes itself on every move
Cursor<T> targetCursor = target.localizingCursor();
RandomAccess<BitType> sourceRandomAccess = source.randomAccess();
// iterate over the input cursor
while (targetCursor.hasNext()) {\
// move input cursor forward
targetCursor.fwd();
// set the output cursor to the position of the input cursor
sourceRandomAccess.setPosition(targetCursor);
// set the value of this pixel of the output image
BitType b = sourceRandomAccess.get();
if (b.get()) {
targetCursor.get().setOne();
}
else {
targetCursor.get().setZero();
}
}
}
I'm using OpenGL ES to make a game in Android. I got some code from a tutorial and I'm trying to change it to suit my app but I'm having a problem. I want to dynamically get an image resource using a string passed into a function as the resource name. I know usually you use getIdentifier() in this case, but that returns an int and I need an input stream. Is there any way of getting an input stream from a resource dynamically?
Alternatively, is there a better way of doing this?
Code below:
InputStream is = mContext.getResources().openRawResource(R.drawable.<imagename>);
Bitmap bitmap;
try {
bitmap = BitmapFactory.decodeStream(is);
}
finally {
try {
is.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
yes u can Suppose u have images stored in drawable with naming img1,img2,img3,img4,img5,img6,img7 than
first make an array like
String[] imgarray={"img1","img2","img3","img4","img5","img6","img7"};
public static String PACKAGE_NAME ;
PACKAGE_NAME=getApplicationContext().getPackageName();
Random r = new Random();
int n=r.nextInt(imgarray.length());
int resID = getResources().getIdentifier( PACKAGE_NAME+":drawable/" +imgarray[n] , null, null);
imageview.setImageResource(resID);
if want bitmap image than just add below line
Bitmap bm = BitmapFactory.decodeResource(getResources(),resID);
if u want other way with less coding than see accepted answer at Other Example
We are using the new Java printing API which uses PrinterJob.printDialog(attributes) to display the dialog to the user.
Wanting to save the user's settings for the next time, I wanted to do this:
PrintRequestAttributeSet attributes = loadAttributesFromPreferences();
if (printJob.printDialog(attributes)) {
// print, and then...
saveAttributesToPreferences(attributes);
}
However, what I found by doing this is that sometimes (I haven't figured out how, yet) the attributes get some bad data inside, and then when you print, you get a white page of nothing. Then the code saves the poisoned settings into the preferences, and all subsequent print runs get poisoned settings too. Additionally, the entire point of the exercise, making the settings for the new run the same as the user chose for the previous run, is defeated, because the new dialog does not appear to use the old settings.
So I would like to know if there is a proper way to do this. Surely Sun didn't intend that users have to select the printer, page size, orientation and margin settings every time the application starts up.
Edit to show the implementation of the storage methods:
private PrintRequestAttributeSet loadAttributesFromPreferences()
{
PrintRequestAttributeSet attributes = null;
byte[] marshaledAttributes = preferences.getByteArray(PRINT_REQUEST_ATTRIBUTES_KEY, null);
if (marshaledAttributes != null)
{
try
{
#SuppressWarnings({"IOResourceOpenedButNotSafelyClosed"})
ObjectInput objectInput = new ObjectInputStream(new ByteArrayInputStream(marshaledAttributes));
attributes = (PrintRequestAttributeSet) objectInput.readObject();
}
catch (IOException e)
{
// Can occur due to invalid object data e.g. InvalidClassException, StreamCorruptedException
Logger.getLogger(getClass()).warn("Error trying to read print attributes from preferences", e);
}
catch (ClassNotFoundException e)
{
Logger.getLogger(getClass()).warn("Class not found trying to read print attributes from preferences", e);
}
}
if (attributes == null)
{
attributes = new HashPrintRequestAttributeSet();
}
return attributes;
}
private void saveAttributesToPreferences(PrintRequestAttributeSet attributes)
{
ByteArrayOutputStream storage = new ByteArrayOutputStream();
try
{
ObjectOutput objectOutput = new ObjectOutputStream(storage);
try
{
objectOutput.writeObject(attributes);
}
finally
{
objectOutput.close(); // side-effect of flushing the underlying stream
}
}
catch (IOException e)
{
throw new IllegalStateException("I/O error writing to a stream going to a byte array", e);
}
preferences.putByteArray(PRINT_REQUEST_ATTRIBUTES_KEY, storage.toByteArray());
}
Edit: Okay, it seems like the reason it isn't remembering the printer is that it isn't in the PrintRequestAttributeSet at all. Indeed, the margins and page sizes are remembered, at least until the settings get poisoned at random. But the printer chosen by the user is not here:
[0] = {java.util.HashMap$Entry#9494} class javax.print.attribute.standard.Media -> na-letter
[1] = {java.util.HashMap$Entry#9501} class javax.print.attribute.standard.Copies -> 1
[2] = {java.util.HashMap$Entry#9510} class javax.print.attribute.standard.MediaPrintableArea -> (10.0,10.0)->(195.9,259.4)mm
[3] = {java.util.HashMap$Entry#9519} class javax.print.attribute.standard.OrientationRequested -> portrait
It appears that what you're looking for is the PrintServiceAttributeSet, rather than the PrintRequestAttributeSet.
Take a look at the PrintServiceAttribute interface, and see if the elements you need have been implemented as classes. If not, you can implement your own PrintServiceAttribute class(es).
I'm getting an NPE while trying to read in an image file, and I can't for the life of me figure out why. Here is my line:
BufferedImage source = ImageIO.read(new File(imgPath));
imgPath is basically guaranteed to be valid and right before it gets here it copies the file from the server. When it hits that line, I get this stack trace:
Exception in thread "Thread-26" java.lang.NullPointerException
at com.ctreber.aclib.image.ico.ICOReader.getICOEntry(ICOReader.java:120)
at com.ctreber.aclib.image.ico.ICOReader.read(ICOReader.java:89)
at javax.imageio.ImageIO.read(ImageIO.java:1400)
at javax.imageio.ImageIO.read(ImageIO.java:1286)
at PrintServer.resizeImage(PrintServer.java:981) <---My function
<Stack of rest of my application here>
Also, this is thrown into my output window:
Can't create ICOFile: Can't read bytes: 2
I have no idea what is going on, especially since the File constructor is succeeding. I can't seem to find anybody who has had a similar problem. Anybody have any ideas? (Java 5 if that makes any difference)
I poked around some more and found that you can specify which ImageReader ImageIO will use and read it in that way. I poked around our codebase and found that we already had a function in place for doing EXACTLY what I was trying to accomplish here. Just for anybody else who runs into a similar issue, here is the crux of the code (some of the crap is defined above, but this should help anybody who tries to do it):
File imageFile = new File(filename);
Iterator<ImageReader> imageReaders = ImageIO.getImageReadersByFormatName("jpeg");
if ( imageReaders.hasNext() ) {
imageReader = (ImageReader)imageReaders.next();
stream = ImageIO.createImageInputStream(imageFile);
imageReader.setInput(stream, true);
ImageReadParam param = imageReader.getDefaultReadParam();
curImage = imageReader.read(0, param);
}
Thanks for the suggestions and help all.
The File constructor will almost certainly succeed, regardless of whether it points to a valid/existing file. At the very least, I'd check whether your underlying file exists via the exists() method.
Also note that ImageIO.read is not thread-safe (it reuses cached ImageReaders which are not thread-safe).
This means you can't easily read multiple files in parallel. To do that, you'll have to deal with ImageReaders yourself.
Have you considered that the file may simply be corrupted, or that ImageIO is trying to read it as the wrong type of file?
Googling for the ICOReader class results in one hit: IconsFactory from jide-common.
Apparently they had the same problem:
// Using ImageIO approach results in exception like this.
// Exception in thread "main" java.lang.NullPointerException
// at com.ctreber.aclib.image.ico.ICOReader.getICOEntry(ICOReader.java:120)
// at com.ctreber.aclib.image.ico.ICOReader.read(ICOReader.java:89)
// at javax.imageio.ImageIO.read(ImageIO.java:1400)
// at javax.imageio.ImageIO.read(ImageIO.java:1322)
// at com.jidesoft.icons.IconsFactory.b(Unknown Source)
// at com.jidesoft.icons.IconsFactory.a(Unknown Source)
// at com.jidesoft.icons.IconsFactory.getImageIcon(Unknown Source)
// at com.jidesoft.plaf.vsnet.VsnetMetalUtils.initComponentDefaults(Unknown Source)
// private static ImageIcon createImageIconWithException(final Class<?> baseClass, final String file) throws IOException {
// try {
// InputStream resource =
// baseClass.getResourceAsStream(file);
// if (resource == null) {
// throw new IOException("File " + file + " not found");
// }
// BufferedInputStream in =
// new BufferedInputStream(resource);
// return new ImageIcon(ImageIO.read(in));
// }
// catch (IOException ioe) {
// throw ioe;
// }
// }
What did they do instead?
private static ImageIcon createImageIconWithException(
final Class<?> baseClass, final String file)
throws IOException {
InputStream resource = baseClass.getResourceAsStream(file);
final byte[][] buffer = new byte[1][];
try {
if (resource == null) {
throw new IOException("File " + file + " not found");
}
BufferedInputStream in = new BufferedInputStream(resource);
ByteArrayOutputStream out = new ByteArrayOutputStream(1024);
buffer[0] = new byte[1024];
int n;
while ((n = in.read(buffer[0])) > 0) {
out.write(buffer[0], 0, n);
}
in.close();
out.flush();
buffer[0] = out.toByteArray();
} catch (IOException ioe) {
throw ioe;
}
if (buffer[0] == null) {
throw new IOException(baseClass.getName() + "/" + file
+ " not found.");
}
if (buffer[0].length == 0) {
throw new IOException("Warning: " + file
+ " is zero-length");
}
return new ImageIcon(Toolkit.getDefaultToolkit().createImage(
buffer[0]));
}
So you might want to try the same approach: read the raw bytes and use Toolkit to create an image from them.
"it's a jpeg but doesn't have a jpeg
extension."
That might be it.
It appears that the library AC.lib-ICO is throwing the NPE. Since this library is intended to read the Microsoft ICO file format, a JPEG might be a problem for it.
Consider explicitly providing the format using an alternative method.