SWT Image to/from String
I am trying to convert an SWT Image to String and vice versa:
To String:
Display display = new Display();
final Image image = new Image(display, "c:\test.png");
// Looks good
showImage(image ,600,400);
ImageData imageData = testImage.getImageData();
byte[] data = imageData.data;
String imageString = new String(Base64.encode(data));
Back to image:
byte[] decode = Base64.decode(imageString.getBytes());
decode.toString();
Image c_img = new Image(Display.getCurrent(), stringToInputStream(decode.toString()));
// Throws exception.
showImage(c_image ,600,400);
where:
private static void showImage(final Image image, int w, int h) {
Display display = new Display();
Shell shell = new Shell(display, SWT.SHELL_TRIM | SWT.DOUBLE_BUFFERED);
shell.setLayout(new FillLayout());
shell.addListener(SWT.Paint, new Listener() {
public void handleEvent(Event e) {
GC gc = e.gc;
int x = 10, y = 10;
gc.drawImage(image, x, y);
gc.dispose();
}
});
shell.setSize(w, h);
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
if (image != null && !image.isDisposed()) {
image.dispose();
}
display.dispose();
}
private static InputStream stringToInputStream(String input) {
InputStream is = null;
try {
is = new ByteArrayInputStream(input.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return is;
}
The error when showing the image from String is:
org.eclipse.swt.SWTException: Unsupported or unrecognized format
at org开发者_高级运维.eclipse.swt.SWT.error(SWT.java:4083)
at org.eclipse.swt.SWT.error(SWT.java:3998)
at org.eclipse.swt.SWT.error(SWT.java:3969)
at org.eclipse.swt.internal.image.FileFormat.load(FileFormat.java:82)
at org.eclipse.swt.graphics.ImageLoader.load(ImageLoader.java:130)
at org.eclipse.swt.graphics.ImageDataLoader.load(ImageDataLoader.java:22)
at org.eclipse.swt.graphics.ImageData.<init>(ImageData.java:331)
at org.eclipse.swt.graphics.Image.<init>(Image.java:545)
Am I the first to do this? Or are there some examples showing how this should be done properly?
Certainly this is wrong:
stringToInputStream(decode.toString())
If you call toString()
on a byte array, you don't get the bytes converted to a String
; you get a String
that looks like
byte[@6536753
You need to construct the ByteArrayInputStream
from "decode" itself.
Why you're operating with String? Is byte[] is not good for you? You're adding useless step in your operations converting it.
If someone needs it, I have achieved it with help of this link: http://www.programcreek.com/2009/02/java-convert-image-to-byte-array-convert-byte-array-to-image/
After a lot of tries, using the suggested approach of the question, or also using ImageLoader, I was always getting:
org.eclipse.swt.SWTException: Unsupported or unrecognized format
But with the approach of the link (using Base64.decode and encode) it works.
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