8 Replies Latest reply: Oct 6, 2010 10:05 AM by 762917 RSS

    Direct Manipulation in a File

    802662
      Hi,

      I am using Netbeans as IDE and I want to develop an application for mobile phone to change some bits of Images for Steganography.

      my question is, can i have permission of direct access to change and save some bits of image, while i don't have license?

      Thanks
        • 1. Re: Direct Manipulation in a File
          tschodt
          Hesam wrote:
          I am using Netbeans as IDE and I want to develop an application for mobile phone to change some bits of Images for Steganography.

          my question is, can i have permission of direct access to change and save some bits of image, while i don't have license?
          Are you asking how to access arbitrary bytes in a file using Java?
          Or is this a question about filesystem permissions? (nothing to do with Java).
          Or are you asking if you legally allowed to alter an image for which you do not have a license to use? (nothing to do with Java).
          Or something else?
          • 2. Re: Direct Manipulation in a File
            802662
            Wow,

            OK. Actually, as you told, I want to manipulate arbitrary bits of image. I think it is possible since image is saved in RAM.

            now, I want to save it (this manipulated image) on ROM again.

            My question is here, can I save the image on ROM?

            I have read in some websites that I can't save anything on ROM (because of security issues), if don't sign my application.
            and also, I heard that to sign of application, I have to pay. because this is a student project, I don't want to pay anything.

            So, my question is can I save the image (or any other file such as text files) on ROM, without application sign?

            Thanks again.
            • 3. Re: Direct Manipulation in a File
              tschodt
              Your terminology seems out of whack.
              The whole point of [url http://en.wikipedia.org/wiki/Read-only_memory] ROM (wiki link) is that you cannot write to it.
              Or does ROM mean something else in mobile phone lingo?
              • 4. Re: Direct Manipulation in a File
                802662
                yes, you are right, I couldn't express very well.

                How is this?
                1- I want to load a image file (from EEPROM, Flash or any other technology which is currently used) into memory (RAM).

                2- Manipulating some bits of it.

                3- Save again in its location.


                Is it possible or not?
                • 5. Re: Direct Manipulation in a File
                  Darryl Burke
                  <font size="2">To access the file system, the device must support the optional FileConnection API (JSR-75) and  the MIDlet has to be signed, which costs money.</font>


                  db
                  • 6. Re: Direct Manipulation in a File
                    762917
                    This can be helpful to you, check it:
                    http://download-llnw.oracle.com/javame/config/cldc/ref-impl/midp2.0/jsr118/index.html

                    I search a little about Steganography and what you are trying to do, maybe this can be helpful:
                    public class ImmutableImageFromByteArray extends MIDlet  implements CommandListener
                    {
                      private Display display; 
                      private Form fmMain;         // The main form
                      private Command cmExit;
                    
                      public ImmutableImageFromByteArray()
                      {
                        display = Display.getDisplay(this);
                    
                        cmExit = new Command("Exit", Command.EXIT, 1);
                            
                        fmMain = new Form("");    
                        fmMain.addCommand(cmExit);
                        fmMain.setCommandListener(this);   
                    
                    
                        fmMain.append(new ImageItem(null, imColor, ImageItem.LAYOUT_NEWLINE_BEFORE |ImageItem.LAYOUT_CENTER,   null));      
                    //    fmMain.append(imColor);
                        
                        display.setCurrent(fmMain);
                    
                      }
                    
                    private static Image imColor = Image.createImage(
                        new byte[] {
                          (byte)0x89, (byte)0x50, (byte)0x4E, (byte)0x47, (byte)0x0D, (byte)0x0A, (byte)0x1A, (byte)0x0A, 
                          (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x0D, (byte)0x49, (byte)0x48, (byte)0x44, (byte)0x52, 
                          (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x4F, (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x13, 
                          (byte)0x08, (byte)0x06, (byte)0x00, (byte)0x00, (byte)0x01, (byte)0xA6, (byte)0x7F, (byte)0x60, 
                          (byte)0x9C, (byte)0x00, (byte)0x00, (byte)0x06, (byte)0xBA, (byte)0x49, (byte)0x44, (byte)0x41, 
                          (byte)0x54, (byte)0x78, (byte)0x9C, (byte)0xAD, (byte)0x58, (byte)0x7F, (byte)0x6C, (byte)0x1B, 
                          (byte)0xF5, (byte)0x15, (byte)0xFF, (byte)0x5C, (byte)0x92, (byte)0x2A, (byte)0x4B, (byte)0xCB,
                          .
                          .
                          .
                          .
                        },
                        (int)0,
                        (int)1779
                    );
                    In the link at the top you can find how this method works.
                    i hope this can help you.
                    • 7. Re: Direct Manipulation in a File
                      802662
                      Wow Goariz, Thanks So much.

                      It helps me alot. one thowsend and one times thanks :)

                      Edited by: Hesam on Oct 6, 2010 11:37 AM
                      • 8. Re: Direct Manipulation in a File
                        762917
                        Youre welcome but, you can thank me marking your question like answer and give some points.

                        Thanx.