I fail to understand why my code is giving me HDF5 Library Exceptions. It points at the createScalarDS method as the source of the error. But I believe this method does exist. Can anyone tell me why this code is unable to create an opaque dataset? What should the modification(s) be? Thanks.
public static void createFile(Message message) throws Exception {
// retrieve an instance of H5File
FileFormat fileFormat = FileFormat
.getFileFormat(FileFormat.FILE_TYPE_HDF5);
if (fileFormat == null) {
System.err.println("Cannot find HDF5 FileFormat.");
return;
}
// create a new file with a given file name.
H5File testFile = (H5File) fileFormat.create(fname);
if (testFile == null) {
System.err.println("Failed to create file:" + fname);
return;
}
// open the file and retrieve the root group
testFile.open();
Group root = (Group) ((javax.swing.tree.DefaultMutableTreeNode) testFile
.getRootNode()).getUserObject();
Group g1 = testFile.createGroup("byte arrays", root);
// obtaining the serialized object
byte[] b = serializer.serialize(message);
int len = b.length;
byte[] dset_data = new byte[len + 1];
// Initialize data.
int indx = 0;
for (int jndx = 0; jndx < len; jndx++)
dset_data[jndx] = b[jndx];
dset_data[len] = (byte) (indx);
// create opaque dataset ---- error here…
Datatype dtype = testFile.createDatatype(Datatype.CLASS_OPAQUE,
(len * 4), Datatype.NATIVE, Datatype.NATIVE);
Dataset dataset = testFile.createScalarDS("byte array", g1, dtype,
dims1D, null, null, 0, dset_data);// error shown in this line
// close file resource
testFile.close();
}
I don't have grip on HDF5.
but, you can not directly use CLASS_OPAQUE
An opaque data type is a user-defined data type that can be used in the same way as a built-in data type. To create an opaque type check links:
http://idlastro.gsfc.nasa.gov/idl_html_help/Opaque_Datatypes.html
To create array datatype object:
Result = H5T_ARRAY_CREATE(Datatype_id, Dimensions)
example:
http://idlastro.gsfc.nasa.gov/idl_html_help/H5F_CREATE.html
Related
I want find out, if two audio files are same or one contains the other.
For this I use Fingerprint of musicg
byte[] firstAudio = readAudioFileData("first.mp3");
byte[] secondAudio = readAudioFileData("second.mp3");
FingerprintSimilarityComputer fingerprint =
new FingerprintSimilarityComputer(firstAudio, secondAudio);
FingerprintSimilarity fingerprintSimilarity = fingerprint.getFingerprintsSimilarity();
System.out.println("clip is found at " + fingerprintSimilarity.getScore());
to convert audio to byte array I use sound API
public static byte[] readAudioFileData(final String filePath) {
byte[] data = null;
try {
final ByteArrayOutputStream baout = new ByteArrayOutputStream();
final File file = new File(filePath);
final AudioInputStream audioInputStream = AudioSystem.getAudioInputStream(file);
byte[] buffer = new byte[4096];
int c;
while ((c = audioInputStream.read(buffer, 0, buffer.length)) != -1) {
baout.write(buffer, 0, c);
}
audioInputStream.close();
baout.close();
data = baout.toByteArray();
} catch (Exception e) {
e.printStackTrace();
}
return data;
}
but when I execute it, I became at fingerprint.getFingerprintsSimilarity() an Exception.
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 15999
at com.musicg.fingerprint.PairManager.getPairPositionList(PairManager.java:133)
at com.musicg.fingerprint.PairManager.getPair_PositionList_Table(PairManager.java:80)
at com.musicg.fingerprint.FingerprintSimilarityComputer.getFingerprintsSimilarity(FingerprintSimilarityComputer.java:71)
at Main.main(Main.java:42)
How can I compare 2 mp3 files with fingerprint in Java?
I never did any audio stuff in Java before, but I looked into your code briefly. I think that musicg only works for WAV files, not for MP3. Thus, you need to convert the files first. A web search reveals that you can e.g. use JLayer for that purpose. The corresponding code looks like this:
package de.scrum_master.so;
import com.musicg.fingerprint.FingerprintManager;
import com.musicg.fingerprint.FingerprintSimilarity;
import com.musicg.fingerprint.FingerprintSimilarityComputer;
import com.musicg.wave.Wave;
import javazoom.jl.converter.Converter;
import javazoom.jl.decoder.JavaLayerException;
public class Application {
public static void main(String[] args) throws JavaLayerException {
// MP3 to WAV
new Converter().convert("White Wedding.mp3", "White Wedding.wav");
new Converter().convert("Poison.mp3", "Poison.wav");
// Fingerprint from WAV
byte[] firstFingerPrint = new FingerprintManager().extractFingerprint(new Wave("White Wedding.wav"));
byte[] secondFingerPrint = new FingerprintManager().extractFingerprint(new Wave("Poison.wav"));
// Compare fingerprints
FingerprintSimilarity fingerprintSimilarity = new FingerprintSimilarityComputer(firstFingerPrint, secondFingerPrint).getFingerprintsSimilarity();
System.out.println("Similarity score = " + fingerprintSimilarity.getScore());
}
}
Of course you should make sure that you do not convert each file again whenever the program starts, i.e. you should check if the WAV files already exist. I skipped this step and reduced the sample code to a minimal working version.
For FingerprintSimilarityComputer(input1, input2), it suppose to take in the fingerprint of the loaded audio data and not the loaded audio data itself.
In your case, it should be:
// Convert your audio to wav using FFMpeg
Wave w1 = new Wave("first.wav");
Wave w2 = new Wave("second.wav");
FingerprintSimilarityComputer fingerprint =
new FingerprintSimilarityComputer(w1.getFingerprint(), w2.getFingerprint());
// print fingerprint.getFingerprintSimilarity()
Maybe I am missing a point, but if I understood you right, this should do:
byte[] firstAudio = readAudioFileData("first.mp3");
byte[] secondAudio = readAudioFileData("second.mp3");
byte[] smaller = firstAudio.length <= secondAudio.lenght ? firstAudio : secondAudio;
byte[] bigger = firstAudio.length > secondAudio.length ? firstAudio : secondAudio;
int ixS = 0;
int ixB = 0;
boolean contians = false;
for (; ixB<bigger.length; ixB++) {
if (smaller[ixS] == bigger[ixB]) {
ixS++;
if (ixS == smaller.lenght) {
contains = true;
break;
}
}
else {
ixS = 0;
}
}
if (contains) {
if (smaller.length == bigger.length) {
System.out.println("Both tracks are equal");
}
else {
System.out.println("The bigger track, fully contains the smaller track starting at byte: "+(ixB-smaller.lenght));
}
}
else {
System.out.println("No track completely contains the other track");
}
I aim to use code via https://github.com/davidgyoung/ble-advert-counter/blob/master/app/src/main/java/com/radiusnetworks/blepacketcounter/MainActivity.java
to scan and read BLE device's adverting data.
The code works well. I could get the formatted adverting data via LogCat as pic shown.
But in the code I can't find the related log statement.
I didnt see BluetoothLeScanner class or onScanResult() method invoked.
And I want to obtain the String "ScanResult{mDevice=F3:E5:7F:73:4F:81, mScanRecord=ScanRecord..." to get the formatted data value.
How can I achieve this?
Thanks
I'm not sure about the logs but here's how you can get the data.
onLeScan() callback has all the information that is being printed in the logs. To get the device information you can use the device object from the call back(ex. device.getAddress()). Scan record will be in the callback's scanRecord byte array. You need to parse the array to get the information. I've used below code to parse the scan information.
public WeakHashMap<Integer, String> ParseRecord(byte[] scanRecord) {
WeakHashMap<Integer, String> ret = new WeakHashMap<>();
int index = 0;
while (index < scanRecord.length) {
int length = scanRecord[index++];
//Zero value indicates that we are done with the record now
if (length == 0) break;
int type = scanRecord[index];
//if the type is zero, then we are pass the significant section of the data,
// and we are thud done
if (type == 0) break;
byte[] data = Arrays.copyOfRange(scanRecord, index + 1, index + length);
if (data != null && data.length > 0) {
StringBuilder hex = new StringBuilder(data.length * 2);
// the data appears to be there backwards
for (int bb = data.length - 1; bb >= 0; bb--) {
hex.append(String.format("%02X", data[bb]));
}
ret.put(type, hex.toString());
}
index += length;
}
return ret;
}
Refer the below link to understand about the ble date advertisement.
BLE obtain uuid encoded in advertising packet
Hope this helps.
I have been trying to find a way to write metadata to a PNG and I have tried quite alot.
I can read the data using the pngj library using:
PngReader pngr = new PngReader(file);
pngr.readSkippingAllRows(); // reads only metadata
for (PngChunk c : pngr.getChunksList().getChunks()) {
if (!ChunkHelper.isText(c)) continue;
PngChunkTextVar ct = (PngChunkTextVar) c;
String key = ct.getKey();
String val = ct.getVal();
System.out.print(key + " " + val + "\n" );
}
pngr.close();
And it works great. But I need to write to it.
I have tried:
public boolean writeCustomData(String key, String value) throws Exception {
PngReader pngr = new PngReader(currentImage);
PngWriter png = new PngWriter(new FileOutputStream(currentImage), pngr.imgInfo);
png.getMetadata().setText(key, value);
return true;
}
But this does nothing.
And I have tried using the answer from Writing image metadata in Java, preferably PNG
this works (kinda) but my read function cant see it.
If you want to add a chunk to the image, you must read and write the full image. Example
PngReader pngr = new PngReader(origFile);
PngWriter pngw = new PngWriter(destFile, pngr.imgInfo, true);
// instruct the writer to copy all ancillary chunks from source
pngw.copyChunksFrom(pngr.getChunksList(), ChunkCopyBehaviour.COPY_ALL);
// add a new textual chunk (can also be done after writing the rows)
pngw.getMetadata().setText("my key", "my val");
// copy all rows
for (int row = 0; row < pngr.imgInfo.rows; row++) {
IImageLine l1 = pngr.readRow();
pngw.writeRow(l1);
}
pngr.end();
pngw.end();
If you need more performance, you can read/write the chunks at a lower level, see this example.
Try this:
Stream pngStream = new System.IO.FileStream("smiley.png", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
PngBitmapDecoder pngDecoder = new PngBitmapDecoder(pngStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
BitmapFrame pngFrame = pngDecoder.Frames[0];
InPlaceBitmapMetadataWriter pngInplace = pngFrame.CreateInPlaceBitmapMetadataWriter();
if (pngInplace.TrySave() == true)
{
pngInplace.SetQuery("/Text/Description", "Have a nice day.");
}
pngStream.Close();
hello i am new with byte manipulation in java. i already have byte array with flowing format
1-> datapacketlength (length of name) (first byte)
2-> name (second byte + datapacket length)
3-> datapacketlength (length of datetime)
4-> current date and time
how can i extract the name and current date and time.should i use Arrays.copyOfRange() method.
Regards from
mcd
You can use ByteBuffer and use your current byte array, then use the methods that come with it to get the next float, int etc (such as buffer.getInt and buffer.getFloat).
You can get a portion of your byte array when you create a new bytebuffer by using the wrap method I believe. The possibilities are endless :). To get strings as you asked, you simply need to do something like:
byte[] name = new byte[nameLength];
buffer.get(name);
nameString = byteRangeToString(name);
where byteRangeToString is a method to return a new string representation of the byte[] data you pass it.
public String byteRangeToString(byte[] data)
{
try
{
return new String(data, "UTF-8");
}
catch (UnsupportedEncodingException e)
{
/* handle accordingly */
}
}
See: http://developer.android.com/reference/java/nio/ByteBuffer.html
Using copyOfRange() may run you into memory issues if used excessively.
What about something like :
int nameLength = 0;
int dateLength = 0;
byte[] nameByteArray;
byte[] dateByteArray
for(int i=0; i<bytesArray.length; i++){
if(i == 0){
nameLength = bytesArray[i] & 0xFF;
nameByteArray = new byte[nameLength];
}
else if(i == nameLength+1){
dateLength = byteArray[i] & 0xFF;
dateByteArray = new byte[dateLength];
}
else if(i < nameLength+1){
nameByteArray[i-1] = bytesArray[i];
}
else{
dateByteArray[i-(nameLength+1)] = bytesArray[i];
}
}
You want to use a DataInputStream.
I am trying to create a sort of simple GUI where im trying to save a couple of Strings and doubles and one int, im using the basic property of OOP which is inheritance I created a class Autos which is essentially the super Class.
The problem seem to arise in a method called "cargarDatosAutos" this is in my GUI class, and here is the code:
private void cargarDatosAutos()
{
regInt = at.numRegistros(); // number of registry
if (regInt != -1)
{
curInt = 0;
ats = new AutosRentables[regInt];
try
{
RandomAccessFile f = new RandomAccessFile("Autos.txt", "rw");
at.cargarDatos(f, ats, regInt); // method in subclass
f.close();
}
catch (IOException ex)
{
Logger.getLogger(Interfaz3.class.getName()).log(Level.SEVERE, null, ex);
}
this.mostrarAutos(ats[0]); // shows data
}
}
Here are the errors:
4-Dec-2011 11:35:20 PM rent_autos.Interfaz3 cargarDatosAutos
SEVERE: null
java.io.EOFException
at java.io.RandomAccessFile.readChar(RandomAccessFile.java:695)
at rent_autos.Autos.leerModelo(Autos.java:139)
at rent_autos.AutosRentables.cargarDatos(AutosRentables.java:84)
at rent_autos.Interfaz3.cargarDatosAutos(Interfaz3.java:6076)
at rent_autos.Interfaz3.<init>(Interfaz3.java:38)
at rent_autos.Interfaz3$159.run(Interfaz3.java:6107)
the leerModelo is a method that reads strings:
public String leerModelo(RandomAccessFile file) throws IOException
{
char cadena[] = new char[25], temp;
for (int c = 0; c < cadena.length; c++)
{
temp = file.readChar();
cadena[c] = temp;
}
return new String(cadena).replace('\0', ' ');
}
And the cargarDatos is to load my data:
public void cargarDatos(RandomAccessFile file, AutosRentables[] lista, int reg) throws IOException
{
int cont = 0;
do
{
modelo = this.leerModelo(file);
color = this.leerColor(file);
tipoAM = this.leerTipoAM(file);
rendimientoGalon = file.readDouble();
placa = this.leerPlaca(file);
ACRISS = this.leerACRISS(file);
codigo = file.readInt();
costo = file.readDouble();
marca = this.leerMarca(file);
detalles = this.leerDetalles(file);
lista[cont] = new AutosRentables(modelo, color, tipoAM, rendimientoGalon, placa, ACRISS, codigo, costo, marca, detalles);
cont++;
System.out.println("Entra");
}
while (cont < reg);
}
And heres the ArrayoutOfbound error:
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 0
at rent_autos.Interfaz3.cargarDatosAutos(Interfaz3.java:6081)
at rent_autos.Interfaz3.<init>(Interfaz3.java:38)
at rent_autos.Interfaz3$159.run(Interfaz3.java:6107)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
So if anyone knows whats going on please help me out here... is it the byte size of the file?, I really dont know, HELP!
EOFException means you tried to read past the end of the stream; i.e. the end of the file in this case. Probably you aren't positioning yourself correctly in the file. Reading chars from a random access file is tricky as you can't know how many bytes they are encoded as. I suspect you need to redesign the file actually. Or else you should be reading bytes not chars if it is coming from an external system?
java.io.EOFException:
For java.io.EOFException check this link http://docs.oracle.com/javase/1.4.2/docs/api/java/io/EOFException.html.
ArrayOutOfBounds:
Out of bounds exception is occurred when you try to access an array with index that exceeded its length. maximum index of a java array is (length -1). It means that you are trying to insert a value into an array element taht doesnt exist.
For handling it you should make sure that your program doesn't access an array with index bigger than length - 1.