Java gif图片转换为jpg格式

if(fileName.toLowerCase().endsWith(".gif")){//由于头像上传支持JPG、JPEG、BMP、GIF、PNG格式图片.而商汤人脸设备仅支持JPG、JPEG、BMP、PNG,故如图片为GIF格式需要转换
   fileParams.put("avatarFile", api.GifToJpg(avatar_file));
 }else{
   fileParams.put("avatarFile", api.getBytes(avatar_file));
 }

/**
  * 将文件转换为byte二进制流
  * @param f
  * @return
  */
 public static byte[] getBytes(File f) {
  try {
   InputStream in = new FileInputStream(f);
   ByteArrayOutputStream out = new ByteArrayOutputStream(1024);
   byte[] b = new byte[1024];
   int n;
   while ((n = in.read(b)) != -1)
    out.write(b, 0, n);
   in.close();
   out.close();
   return out.toByteArray();
  } catch (IOException e) {
   logger.error("***请设置文件路径***");
   e.printStackTrace();
  }
  return null;
 }
 /**
  * 将gif格式图片转换为jpg格式文件，并直接返回byte二进制流
  * @param file
  * @return
  */
 public static byte[] GifToJpg(File file){
  BufferedImage bufferedImage;
  ByteArrayOutputStream out = new ByteArrayOutputStream(1024);
  try {
   // read image file
   bufferedImage = ImageIO.read(file);
   // create a blank, RGB, same width and height, and a white
   BufferedImage newBufferedImage = new BufferedImage(
     bufferedImage.getWidth(), bufferedImage.getHeight(),
     BufferedImage.TYPE_INT_RGB);
   // TYPE_INT_RGB:创建一个RBG图像，24位深度，成功将32位图转化成24位
   newBufferedImage.createGraphics().drawImage(bufferedImage, 0, 0,Color.WHITE, null);
   // write to jpeg file
   ImageIO.write(newBufferedImage, "jpg",out);//转换输出到二进制数组流
   //ImageIO.write(newBufferedImage, "jpg",new File("c:\\java.jpg"));//转换输出到文件
   return out.toByteArray();//二进制流
  } catch (IOException e) {
   logger.error("***GifToJpg方法报错***");
   e.printStackTrace();
  }
  return null;
 }

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
public class ConvertImageFile {
 public static void main(String[] args) {
 BufferedImage bufferedImage;
 try {
  //read image file
  bufferedImage = ImageIO.read(new File("c:\\java.png"));
  // create a blank, RGB, same width and height, and a white background
  BufferedImage newBufferedImage = new BufferedImage(bufferedImage.getWidth(),
   bufferedImage.getHeight(), BufferedImage.TYPE_INT_RGB);
  //TYPE_INT_RGB:创建一个RBG图像，24位深度，成功将32位图转化成24位
  newBufferedImage.createGraphics().drawImage(bufferedImage, 0, 0, Color.WHITE, null);
  // write to jpeg file
  ImageIO.write(newBufferedImage, "jpg", new File("c:\\java.jpg"));
  System.out.println("Done");
 } catch (IOException e) {
  e.printStackTrace();
 }
 }
}