JAI API...Why color change?

Question

I wanna to use n parts of pictures to be one. When I use png/gif, production picture looks normal. Why I use
jpeg/bmp, my production picture will change any color to red. Please tell me why? The reason is "outImage.setSample"??
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import javax.media.jai.*;
import javax.media.jai.widget.*;
import javax.media.jai.iterator.*;
public class imageConvert3 {
     public String align;
     public String[] inputFiles;
     public int parts;
     public imageConvert3() {
     } // --- < public imageConvert3() > ---
     public String getAlign() {
          return this.align;
     } // --- < public String getAlign() > ---
     public String[] getInputFiles() {
return this.inputFiles;
     } // --- < public String[] getInputFiles() > ---
     public int getParts() {
return this.parts;
     } // --- end of < public void getParts() > ---
     public void setAlign(String align) {
          this.align = align;
     } // --- end of < public void setAlign(String align) > ---
     public void setInputFiles(String[] inputFiles) {
this.inputFiles = inputFiles;
     } // --- end of < public void setInputFiles(String[] inputFiles) > ---
     public void setParts(int parts) {
this.parts = parts;
     } // --- end of < public void setParts(int parts) > ---
     public String convert() {
          RenderedOp[] inputPictures = new RenderedOp[inputFiles.length];
          RandomIter[] iterPictures = new RandomIter[inputFiles.length];
          TiledImage outImage;
          // setting second File Name
          String sfName = inputFiles[0].substring(inputFiles[0].lastIndexOf(".") + 1, inputFiles[0].length());
          String fName = "";
          // <0>Setting File Name
          // <1>Create input image
          // <2>Use the access the source image
          for (int i = 0; i < inputFiles.length; i++) {
               //<0>
               fName = fName + inputFiles.substring(0, inputFiles[i].lastIndexOf("."));
               //<1>
               inputPictures[i] = JAI.create("fileload", "images\\" + inputFiles[i]);               
               //<2>
               iterPictures[i] = RandomIterFactory.create(inputPictures[i], null);
          } // --- < for (int i = 0; i < inputFiles.length(); i++) > ---
          int bands = inputPictures[0].getSampleModel().getNumBands();
          // Define height/width
          int height, unitHeight;
          int width, unitWidth;
          unitHeight = inputPictures[0].getHeight();
          unitWidth = inputPictures[0].getWidth();
          if (align.equals("vertical")) {
               height = unitHeight * parts;
               width = unitWidth;
          else {
               height = unitHeight;
               width = unitWidth * parts;
          } // --- end of < if (align.equals("vertical")) > ---
          // Create the out image
          outImage = new TiledImage(inputPictures[0].getMinX(),
                                        inputPictures[0].getMinY(),
                                        width,
                                        height,
                                        inputPictures[0].getMinX(),
                                        inputPictures[0].getMinY(),
                                        inputPictures[0].getSampleModel(),
                                        inputPictures[0].getColorModel());
          // setSample
          for (int cnts = 0; cnts < parts; cnts++) {
               int yy = 0;
               System.out.println("Generate " + inputFiles[cnts] + "---\n");
               if (align.equals("vertical")) {
                    for (int y = cnts * unitHeight; y < (cnts + 1) * unitHeight ; y++) {
                         int xx = 0;
                         for (int x = 0; x < unitWidth; x++) {
                              try {
                                   outImage.setSample(x, y, 0, iterPictures[cnts].getSample(xx, yy, 0));
                              } catch (Exception ec) {
                              xx++;
                         } // --- < for (int x = 0; x < unitWight; x++) > ---
                         yy++;
                    } // --- < for (int y = cnts * unitHeight; y < (cnts + 1) * unitHeight ; y++) > ---
               else {
                    for (int y = 0; y < unitHeight ; y++) {
                         int xx = 0;
                         for (int x = cnts * unitWidth; x < (cnts + 1 ) * unitWidth; x++) {
                              try {
                                   outImage.setSample(x, y, 0, iterPictures[cnts].getSample(xx, yy, 0));
                              } catch (Exception ec) {
                              xx++;
                         } // --- < for (int y = 0; y < unitHeight ; y++) > ---
                         yy++;
                    } // --- < for (int x = cnts * unitWight; x < (cnts + 1 ) * unitWight; x++) > ---
               } // --- < if (align.equals("vertical")) > ---
          } // --- < for (int x = 0; x < unitWight; x++) > ---
          // Write the image to a file
          RenderedOp op = JAI.create("filestore",
                                        outImage,
                                        "images\\new\\" +
                                        fName + "." + sfName,
                                        "PNG",
                                        null);
          return "scuccessful!";
     } // --- end of < public String mergeParts2OneImage() > ---
     public static void main (String args[]) {
          imageConvert3 img = new imageConvert3();
          String[] flist = new String[3];
          flist[0] = "head1.png";
          flist[1] = "body1.png";
          flist[2] = "foot1.png";
          img.setAlign("horizontal");
          img.setParts(3);
          img.setInputFiles(flist);
          img.convert();
} // --- end of < public class imageConvert3 > ---
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Thanks a lot!

Answer 1

The samples you are writing into the outImage object may not be compatible with each other, so that is probably why your resulting colors are invalid. You need to add compatible samples. I am assuming this problems stems from the fact that your source data is coming from various image file types, which most likely have different sample/color types among them.