Batch image watermark processing using Java technology

Source: Internet
Author: User

Steps:

1. Build a Web project [complete]
2. Writing Web pages (containing pictures)
3. Write a filter to add a watermark to all the requested pages

Core code:

/**
* All requests are subject to this filtering method
*/
public void DoFilter (ServletRequest req, servletresponse Res,
Filterchain chain) throws IOException, Servletexception {

HttpServletRequest request = (httpservletrequest) req;
1. Get the context path/watermark
String path = Request.getcontextpath ();
2. Get the request path/watermark/images/img1.jpg
String RequestUri = Request.getrequesturi ();
3. Get the physical path to the picture
This can also get the project's release path
Realpath+requesturi can get the full path of the picture
String Realpath=request.getrealpath ("/");
Left and right slashes are not affected
String Realpath = Request.getsession (). Getservletcontext (). Getrealpath (
"/")
+ RequestUri
. substring (requesturi.indexof (path) + path.length ());
4. Read the picture from the request into the byte buffer
FileInputStream fis = new FileInputStream (Realpath);
Create a picture buffer
byte[] Imagebuff = new byte[fis.available ()];
Read in picture byte data
Fis.read (Imagebuff);
5. Get the original height and width of the picture
Image image = new ImageIcon (imagebuff). GetImage ();
int imgwidth = Image.getwidth (null);
int imgheight = Image.getheight (null);
6. Synthesizing text information into a picture buffer
BufferedImage bufferedimage = new BufferedImage (ImgWidth, ImgHeight,
BUFFEREDIMAGE.TYPE_INT_RGB);
Graphics g = bufferedimage.creategraphics ();
Loading the image data in
G.drawimage (image, 0, 0, imgwidth, imgheight, NULL);
Draw text
G.setcolor (color.red); Set Text color
Font f = new Font ("script", Font.Italic, 30); Create font, font style, font size
G.setfont (f); Set font
g.DrawString ("Senior Java Engineer", 300, 900);
g.DrawString ("qq:425336980", 320, 940);
G.dispose ();
7. Converting the image of a buffer to a byte array
Bytearrayoutputstream out = new Bytearrayoutputstream ();
JPEGImageEncoder encoder = Jpegcodec.createjpegencoder (out);
Encode data from an image buffer into JPEG format
Encoder.encode (BufferedImage);
Convert images in JPEG format to byte arrays
byte[] Resultdata = Out.tobytearray ();
Out.close ();

8. Send the converted JPEG byte array data directly to the servlet response stream for output
Res.setcontentlength (resultdata.length);
Res.getoutputstream (). write (Resultdata);
Res.getoutputstream (). Close ();

Chain.dofilter (req, res);
}

Case Download: Http://pan.baidu.com/s/1pJiTePH


Batch image watermark processing using Java technology

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.