Reputation:
I'm having an image in Database in bytearray format. I want to display on browser. I don't know how to write Image using OutputStream. Here is my code.
byte[] imageInBytes = (byte[]) obj; // from Database
InputStream in = new ByteArrayInputStream(imageInBytes);
Image img = ImageIO.read(in).getScaledInstance(50, -1, Image.SCALE_SMOOTH);
OutputStream o = resp.getOutputStream(); // HttpServletResponse
o.write(imgByte);
Upvotes: 2
Views: 7596
Reputation: 1701
You have to set the content type of the response to be an image type that you are sending. Suppose your image was stored when it was a jpeg. then,
OutputStream o = resp.getOutputStream(); // HttpServletResponse
o.setContentType("image/jpeg");
o.write(img.getBytes() /* imgByte */);
would send the browser an image. ( The browser understands from the header information that the following information you just sent it, is a jpeg image. )
Upvotes: 1
Reputation: 347332
You could try using ImageIO.write
...
ImageIO.write(img, "jpg", o);
But this will require you to use BufferedImage
when reading...
BufferedImage img = ImageIO.read(in);
You could then use AffineTransform
to scale the image...
BufferedImage scaled = new BufferedImage(img.getWidth() / 2, img.getHeight() / 2, img.getType());
Graphics2D g2d = scaled.createGraphics();
g2d.setTransform(AffineTransform.getScaledInstance(0.5, 0.5));
g2d.drawImage(img, 0, 0, null);
g2d.dispose();
img = scaled;
This, obviously, only scales the image by 50%, so you'll need to calculate the required scaling factor based on the original size of the image against your desired size...
Take a look at Java: maintaining aspect ratio of JPanel background image for some ideas on scaling images...
Upvotes: 0
Reputation: 172628
You may try something like this:
File f=new File("image.jpg");
BufferedImage o=ImageIO.read(f);
ByteArrayOutputStream b=new ByteArrayOutputStream();
ImageIO.write(o, "jpg", b);
byte[] img=b.toByteArray();
Upvotes: 1