I can successfully send and draw a resized, 125 x 125 image from my client to my server. only problem is, thats way too small. I want to be able to send a larger image but the byte array can't handle it and I get a java heap exception. currently I'm using this to interpret my image. Is there a more efficient way?
On the client
screenShot = new Robot().createScreenCapture(new Rectangle(Toolkit.getDefaultToolkit().getScreenSize()));
screenShot = resize(screenShot, 125, 125);
ByteArrayOutputStream byteArrayO = new ByteArrayOutputStream();
ImageIO.write(screenShot,"PNG",byteArrayO);
byte [] byteArray = byteArrayO.toByteArray();
out.writeLong(byteArray.length);
out.write(byteArray);
resize method as called above.
public static BufferedImage resize(BufferedImage img, int newW, int newH) {
int w = img.getWidth();
int h = img.getHeight();
BufferedImage dimg = new BufferedImage(newW, newH, img.getType());
Graphics2D g = dimg.createGraphics();
g.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g.drawImage(img, 0, 0, newW, newH, 0, 0, w, h, null);
g.dispose();
return dimg;
}
server that interprets the image
in = new DataInputStream(Client.getInputStream());
long nbrToRead = in.readLong();
byte[] byteArray = new byte[(int) nbrToRead];
int nbrRd = 0;
int nbrLeftToRead = (int) nbrToRead;
while (nbrLeftToRead > 0) {
int rd = in.read(byteArray, nbrRd, nbrLeftToRead);
if (rd < 0)
break;
nbrRd += rd; // accumulate bytes read
nbrLeftToRead -= rd;
}
ByteArrayInputStream byteArrayI = new ByteArrayInputStream(
byteArray);
image = ImageIO.read(byteArrayI);
if (image != null) {
paint(f.getGraphics(), image);
} else {
System.out.println("null image.");
}
as you can tell the code is massive and most likely inefficient. I could send 1/10 of the image 10 times for with and height, drawing on those parts instead but I wanted to know if there was an easier way to do this.
You should probably think of transferring data as stream over the network. You can make use of third-party libraries like RMIIO . In case you can make data transfer using web service then you can look at Message Transmission Optimization Mechanism (MTOM) which lets you transfer data as stream in more efficient manner. For more details please have a look here
this worked for me
public class ImageClient {
public static void main(String[] args) throws AWTException, IOException {
BufferedImage screenShot = new Robot().createScreenCapture(new Rectangle(Toolkit.getDefaultToolkit().getScreenSize()));
Socket socket = new Socket("localhost",11111);
MemoryCacheImageOutputStream byteArrayO = new MemoryCacheImageOutputStream(socket.getOutputStream());
ImageIO.write(screenShot, "PNG", byteArrayO);
byteArrayO.flush();
socket.close();
}
}
public class ImageServer {
public static void main(String[] args) throws IOException, ClassNotFoundException {
ServerSocket ss = new ServerSocket(11111);
try{
Socket s = ss.accept();
InputStream is = s.getInputStream();
MemoryCacheImageInputStream ois = new MemoryCacheImageInputStream(is);
ImageIO.read(ois);
s.close();
}finally{
ss.close();
}
}
}
Related
I am receiving a MultipartFile Spring object from rest controller. I am trying to convert any inage file to JPG image but I just need the byte array to save it on mongoDb
I found this code to do that
public boolean convertImageToJPG(InputStream attachedFile) {
try {
BufferedImage inputImage = ImageIO.read(attachedFile);
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
boolean result = ImageIO.write(inputImage, "jpg", byteArrayOutputStream);
return result;
} catch (IOException e) {
System.err.println("Error " + e);
}
return false;
}
But result as a false with not error, so ImageIO.write is not working
Also I found this to do the same but using File object, I don't want to create the file on directory, I just need the byte array
public static boolean convertFormat(String inputImagePath,
String outputImagePath, String formatName) throws IOException {
FileInputStream inputStream = new FileInputStream(inputImagePath);
FileOutputStream outputStream = new FileOutputStream(outputImagePath);
// reads input image from file
BufferedImage inputImage = ImageIO.read(inputStream);
// writes to the output image in specified format
boolean result = ImageIO.write(inputImage, formatName, outputStream);
// needs to close the streams
outputStream.close();
inputStream.close();
return result;
}
Testing
public class TestImageConverter {
public static void main(String[] args) {
String inputImage = "D:/Photo/Pic1.jpg";
String oututImage = "D:/Photo/Pic1.png";
String formatName = "PNG";
try {
boolean result = ImageConverter.convertFormat(inputImage,
oututImage, formatName);
if (result) {
System.out.println("Image converted successfully.");
} else {
System.out.println("Could not convert image.");
}
} catch (IOException ex) {
System.out.println("Error during converting image.");
ex.printStackTrace();
}
}
}
How can I solve my problem?
UPDATED SOLUTION (alternative with no need for Raster and ColorModel)
It had indeed bothered me that my older solution (see below) still required Rasters and ColorModels. I got challenged on my solution, so I spent some more time looking for alternatives. So the best thing I could come up with now is the following:
try {
final FileInputStream fileInputStream = new FileInputStream("dice.png");
final BufferedImage image = ImageIO.read(fileInputStream);
fileInputStream.close(); // ImageIO.read does not close the input stream
final BufferedImage convertedImage = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_RGB);
convertedImage.createGraphics().drawImage(image, 0, 0, Color.WHITE, null);
final FileOutputStream fileOutputStream = new FileOutputStream("dice-test.jpg");
final boolean canWrite = ImageIO.write(convertedImage, "jpg", fileOutputStream);
fileOutputStream.close(); // ImageIO.write does not close the output stream
if (!canWrite) {
throw new IllegalStateException("Failed to write image.");
}
} catch (IOException e) {
e.printStackTrace();
}
I ended up with a copy of the BufferedImage as I did before. It does more or less the same thing, but you can actually reuse the ColorModel and Raster more easily.
drawImage() seems to take care of most of what I did before manually. And since it is standard java library code all the way, it seems indeed to be a better way.
Note that you end up with an Image of type BufferedImage.TYPE_INT_RGB. While it seems to work for the types jpg, png, and gif, I am not sure what will happen to other file formats or files with a different storage ColorModel - information might be lost (e.g. 4 color-channels to 3). For the mentioned types we don't need an alpha channel, even if we convert from gif or jpg to png (it will be Color.WHITE).
OLD SOLUTION
I was not happy with my first design and also it did not quite work the way it should have.
Therefore, I have created one from scratch. I ended up with a little converter for sRGB files. You can convert from png to jpg and vice versa (Edit: Added gif support also). If you want to handle other types feel free to extend this further. You can more or less add it the same way. It might work for other file types as well, but I have not tested them yet. Luckily, it seems that sRGB is quite common though.
Tbh. I have no idea how many combinations and variants (color palettes, precision, quality, b/w, etc.) you can produce or which common properties they share.
Maybe this is good enough for you. Maybe not. At least it was a nice exercise for me.
This solution is by no means perfect. The results looked okay-ish. The file-type conversion worked and the file-size is also smaller than the png.
try {
final String fileName = "dice.png";
final BufferedImage inputImage = ImageIO.read(new FileInputStream(fileName));
final boolean isSRGB = inputImage.getColorModel().getColorSpace().isCS_sRGB();
final String outputFormat = "gif";
if (!isSRGB) {
throw new IllegalArgumentException("Please provide an image that supports sRGB.");
}
final WritableRaster raster = createRaster(inputImage);
final ColorModel colorModel = createColorModel(inputImage);
final BufferedImage outputImage = new BufferedImage(colorModel, raster, colorModel.isAlphaPremultiplied(), null);
final String outputFileName = fileName + "-converted." + outputFormat;
final boolean writeResult = ImageIO.write(outputImage, outputFormat, new FileOutputStream(outputFileName));
if (!writeResult) {
throw new IllegalStateException("Could not convert file: " + fileName + " to format: " + outputFormat);
}
System.out.println(">> Created file: " + outputFileName);
} catch (Exception e) {
e.printStackTrace();
}
#NotNull
public static ColorModel createColorModel(#NotNull BufferedImage bufferedImage) {
Objects.requireNonNull(bufferedImage);
final int type = bufferedImage.getType();
boolean isAlphaPremultiplied = false;
int transparency = Transparency.OPAQUE;
if (type == BufferedImage.TYPE_3BYTE_BGR) {
isAlphaPremultiplied = true;
}
return new ComponentColorModel(
ColorModel.getRGBdefault().getColorSpace(),
false, isAlphaPremultiplied, transparency,
bufferedImage.getData().getDataBuffer().getDataType()
);
}
#NotNull
public static WritableRaster createRaster(#NotNull BufferedImage bufferedImage) {
Objects.requireNonNull(bufferedImage);
final int type = bufferedImage.getType();
final int width = bufferedImage.getWidth();
final int height = bufferedImage.getHeight();
final int pixelStride = 3;
int[] offset = new int[]{0, 1, 2};
DataBufferByte dataBufferByte;
if (type == BufferedImage.TYPE_4BYTE_ABGR || type == BufferedImage.TYPE_BYTE_INDEXED) {
int dataIndex = 0;
final byte[] data = new byte[height * width * pixelStride];
final int bitmask = 0xff;
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
final int rgb = bufferedImage.getRGB(x, y);
final int blue = bitmask & rgb;
final int green = bitmask & (rgb >> 8);
final int red = bitmask & (rgb >> 16);
if (rgb == 0) {
data[dataIndex++] = (byte) bitmask;
data[dataIndex++] = (byte) bitmask;
data[dataIndex++] = (byte) bitmask;
} else {
data[dataIndex++] = (byte) red;
data[dataIndex++] = (byte) green;
data[dataIndex++] = (byte) blue;
}
}
}
dataBufferByte = new DataBufferByte(data, data.length);
} else if (type == BufferedImage.TYPE_3BYTE_BGR) {
dataBufferByte = (DataBufferByte) bufferedImage.getRaster().getDataBuffer();
offset = new int[]{2, 1, 0};
} else {
throw new IllegalArgumentException("Cannot create raster for unsupported image type.");
}
return Raster.createInterleavedRaster(
dataBufferByte, width, height,
pixelStride * width, pixelStride,
offset,
null
);
}
EDIT: Added support for gif.
I've written a small application for personal use in macOs using java (the only language I know) that reads a directory and compare the images found in it with every other image.
Edit: As user dbush pointed out, here is the code I should've posted:
for (int i = 0; i < files.size(); i++) {
file1 = files.get(i).getAbsolutePath();
for (int j = i + 1; j < files.size(); j++) {
file2 = files.get(j).getAbsolutePath();
System.out.println("Comparing " + files.get(i).getName() + sp + files.get(j).getName());
System.out.println(Arrays.equals(extractBytes(file1), extractBytes(file2)));
}
}
private static byte[] extractBytes(String imageName) throws IOException {
// open image
File imgPath = new File(imageName);
BufferedImage bufferedImage = getSample(imgPath);
// get DataBufferBytes from Raster
WritableRaster raster = bufferedImage.getRaster();
DataBufferByte data = (DataBufferByte) raster.getDataBuffer();
return (data.getData());
}
private static BufferedImage getSample(File f) {
BufferedImage img = null;
Rectangle sourceRegion = new Rectangle(0, 0, 10, 10); // The region you want to extract
try {
ImageInputStream stream1 = ImageIO.createImageInputStream(f); // File or input stream
Iterator<ImageReader> readers = ImageIO.getImageReaders(stream1);
if (readers.hasNext()) {
ImageReader reader = readers.next();
reader.setInput(stream1);
ImageReadParam param = reader.getDefaultReadParam();
param.setSourceRegion(sourceRegion); // Set region
img = reader.read(0, param); // Will read only the region specified
}
} catch (IOException e) {
System.out.println(e);
}
return img;
}
It involves reading two images in a byte array and comparing both. The problem is that it takes a long time to do this, even if I sample a small portion of each image.
Should I re-write the same application in C or swift for better performance, considering I'll be running it on macOs from the terminal? Or it will do minimal difference.
Thanks a lot in advance!
I want to resize an image and then to write it back to outputstream, for this I need to convert the scaled image into bytes, how can I convert it?
ByteArrayInputStream bais = new ByteArrayInputStream(ecn.getImageB());
BufferedImage img = ImageIO.read(bais);
int scaleX = (int) (img.getWidth() * 0.5);
int scaleY = (int) (img.getHeight() * 0.5);
Image newImg = img.getScaledInstance(scaleX, scaleY, Image.SCALE_SMOOTH);
outputStream.write(newImg); //cannot resolve
how to fix outputStream.write(newImg)???
Use this method for scaling:
public static BufferedImage scale(BufferedImage sbi,
int imageType, /* type of image */
int destWidth, /* result image width */
int destHeight, /* result image height */
double widthFactor, /* scale factor for width */
double heightFactor /* scale factor for height */ )
{
BufferedImage dbi = null;
if(sbi != null) {
dbi = new BufferedImage(destWidth, destHeight, imageType);
Graphics2D g = dbi.createGraphics();
AffineTransform at = AffineTransform.getScaleInstance(widthFactor, heightFactor);
g.drawRenderedImage(sbi, at);
}
return dbi;
}
Then you'll have a BufferedImage which you can write to a byte array
public static byte[] writeToByteArray(BufferedImage bi, String dImageFormat) throws IOException, Exception {
byte[] scaledImageData = null;
ByteArrayOutputStream baos = null;
try {
if(bi != null) {
baos = new ByteArrayOutputStream();
if(! ImageIO.write(bi, dImageFormat, baos)) {
throw new Exception("no appropriate writer found for the format " + dImageFormat);
}
scaledImageData = baos.toByteArray();
}
} finally {
if(baos != null) {
try {
baos.close();
} catch(Exception e) {
e.printStackTrace();
}
}
}
return scaledImageData;
}
Include this line and check:-
ByteArrayOutputStream outputStream=new ByteArrayOutputStream();
ImageIO.write(originalImage, "jpg", outputStream);
byte[] imageInByte=outputStream.toByteArray();
So I try to create an image from a byte array, but I can't figure out why the ImageIO.read() method returns a null pointer without any exception.
#Override
public int setParam(byte[] buffer) {
mFlag = buffer[0]; //TODO
mX = Convertor.convert2BytesToInt(buffer[1], buffer[2]);
mY = Convertor.convert2BytesToInt(buffer[3], buffer[4]);
mWidth = Convertor.convert2BytesToInt(buffer[5], buffer[6]);
mHeight = Convertor.convert2BytesToInt(buffer[7], buffer[8]);
mLength = Convertor.convert4BytesToInt(buffer[9], buffer[10], buffer[11], buffer[12]);
byte[] bufferpix = Arrays.copyOfRange(buffer, 13, 13+mLength);
ByteArrayInputStream in = new ByteArrayInputStream(bufferpix);
try {
mImage = ImageIO.read(in);
} catch (IOException e) {
e.printStackTrace();
}
return 13+mLength;
}
#Override
public void draw(Graphics2D g, ArrayList<Color> palette) {
System.out.print("Draw Image\n");
g.drawImage(mImage, mX, mY, mWidth, mHeight, null);
}
The buffer seems to be okay, it contains data RGBA (1 byte for each, so 4 bytes per pixels).
Do you see any problem with that usage?
Thx
Btw, if you wonder, this buffer has previously been created by the Android class Bitmap.
I wasn't using the right method:
int[] bufferpix = new int[mLength];
for(int i=0; i<mLength;i++){
bufferpix[i] = buffer[i+13];
}
mImage = new BufferedImage(mWidth, mHeight, BufferedImage.TYPE_4BYTE_ABGR_PRE);
mImage.getRaster().setPixels(0, 0, mWidth, mHeight, bufferpix);
This fill my image correctly.
Too bad that setPixels can't take a byte array for parameter, which make the conversion uggly (I haven't look for a better way to copy my bytes array in a int array yet, probably there is one).
So I have a very small piece of code, which takes a .gif image as input, and then it splits this .gif image into an array of BufferedImage. After that, it stores the images in the array on the disk. When I do this, the output images contain heavy white-pixel noise which isn't visible in the input .gif image.
Example of the input gif:
Example of malformed output image (the 3rd frame in the gif):
The code I am using to split the gif is as follows:
public static void main(String[] args) throws Exception {
splitGif(new File("C:\\test.gif"));
}
public static void splitGif(File file) throws IOException {
ImageReader reader = ImageIO.getImageReadersBySuffix("gif").next(); reader.setInput(ImageIO.createImageInputStream(new FileInputStream(file)), false);
for(int i = 0; i < reader.getNumImages(true); i++) {
BufferedImage image = reader.read(i);
ImageIO.write(image, "PNG", new File(i + ".png"));
}
}
Can anyone help me out?
So the problem was that when reading .gif files into java, then all pixels in a given frame that did not change color compared to their previous frame will be fully transparent. If you want to read a .gif and split it in an array of properly rendered BufferedImages, then you have to fill the transparent pixels of the current frame with the last non-transparent pixel of one of the previous frames.
Code:
public static void splitGif(File file) throws IOException {
ImageReader reader = ImageIO.getImageReadersBySuffix("gif").next();
reader.setInput(ImageIO.createImageInputStream(new FileInputStream(file)), false);
BufferedImage lastImage = reader.read(0);
ImageIO.write(lastImage, "PNG", new File(0 + ".png"));
for (int i = 1; i < reader.getNumImages(true); i++) {
BufferedImage image = makeImageForIndex(reader, i, lastImage);
ImageIO.write(image, "PNG", new File(i + ".png"));
}
}
private static BufferedImage makeImageForIndex(ImageReader reader, int index, BufferedImage lastImage) throws IOException {
BufferedImage image = reader.read(index);
BufferedImage newImage = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_4BYTE_ABGR);
if(lastImage != null) {
newImage.getGraphics().drawImage(lastImage, 0, 0, null);
}
newImage.getGraphics().drawImage(image, 0, 0, null);
return newImage;
}
You solved it yourself, but for good order: every next frame is the accumulation of all prior frames filling up the transparent pixels in the current frame.
public static void splitGif(File file) throws IOException {
ImageReader reader = ImageIO.getImageReadersBySuffix("gif").next();
reader.setInput(ImageIO.createImageInputStream(new FileInputStream(file)), false);
BufferedImage outImage = null;
Graphics2D g = null;
for (int i = 0; i < reader.getNumImages(true); i++) {
BufferedImage image = reader.read(i);
if (g == null) {
BufferedImage outImage = new BufferedImage(image.getWidth(), image.getHeight(),
BufferedImage.TYPE_4BYTE_ABGR);
g = (Graphics2D) outImage.getGraphics();
}
g.drawImage(lastImage, 0, 0, null);
ImageIO.write(outImage, "PNG", new File(i + ".png"));
}
if (g != null) {
g.dispose();
}
}
getGraphics==createGraphics should be balanced be a dispose as documented.