将java.awt.*代码转换为Android.graphics.*代码

Question

我正在尝试将一些使用java.awt.*库编写的图形代码移植为使用android.graphics.*库。然而，我对图形没有太多的经验。

这是java.awt.*代码(有效(：

/**
* Converts the given <code>MyImageBitmap</code> to the specified image format and returns it as byte array.
*
* @param myImageBitmapthe given MyImageBitmap, not null
* @param format the given target image format ("png", "gif", "jpg"), not null
* @return the converted data in byte array format, not null
*/
private byte[] convert(MyImageBitmap myImageBitmap, String format) {
final int width = myImageBitmap.getWidth();
final int height = myImageBitmap.getHeight();
final int[] MASKS = {0x000000ff, 0x000000ff, 0x000000ff};
DataBuffer buffer = new DataBufferByte(myImageBitmap.getPixels(), myImageBitmap.getLength());
WritableRaster writableRaster = Raster.createPackedRaster(buffer, width, height, width, MASKS, null);
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
bufferedImage.setData(writableRaster);
try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
ImageIO.write(bufferedImage, format, outputStream);
outputStream.close();
return outputStream.toByteArray();
} catch (IOException e) {
throw new RuntimeException(e);
}
}

这是MyImageBitmap类：

/**
* A <code>MyImageBitmap</code> instance contains an image information in bitmap format.
*/
public class MyImageBitmap implements Serializable {
//...member variables
/**
* Creates an instance of <code>MyImageBitmap</code> with specified data.
*
* @param pixels    the image pixes, not null
* @param width     the image width, not null
* @param height    the image height, not null
* @param ppi       pixel per inch, not null
* @param depth     the image depth, not null
* @param lossyFlag lossy flag, not null
*/
public MyImageBitmap(byte[] pixels, int width, int height, int ppi, int depth, int lossyFlag) {
this.pixels = pixels;
this.width = width;
this.height = height;
this.ppi = ppi;
this.depth = depth;
this.lossyFlag = lossyFlag;
this.length = pixels != null ? pixels.length : 0;
}
//...getters
}

这就是我尝试过的(没有成功(：

private byte[] convert(MyImageBitmap myImageBitmap, String format) {
int width = myImageBitmap.getWidth();
int height = myImageBitmap.getHeight();
byte[] imgRGB888 = myImageBitmap.getPixels();
Bitmap bmp2 = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
int[] colors = new int[width * height];
int r,g,b;
for (int ci = 0; ci < colors.length; ci++)
{
r = (int)(0xFF & imgRGB888[3*ci]);
g = (int)(0xFF & imgRGB888[3*ci+1]);
b = (int)(0xFF & imgRGB888[3*ci+2]);
colors[ci] = Color.rgb(r, g, b);
}
bmp2.setPixels(colors, 0, width, 0, 0, width, height);
Bitmap.CompressFormat compressFormat;
if (format.equals("jpeg")){
compressFormat = android.graphics.Bitmap.CompressFormat.JPEG;
}else if (format.equals("png")){
compressFormat = android.graphics.Bitmap.CompressFormat.PNG;
}else {//must be gif...try to convert to png
compressFormat = android.graphics.Bitmap.CompressFormat.PNG;
}
try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()){
bmp2.compress(compressFormat, 100, outputStream);
return outputStream.toByteArray();
} catch (IOException e) {
throw new RuntimeException(e);
}
}

当我运行上面的代码(我尝试移植awt代码(时，我在这行r = (int)(0xFF & imgRGB888[3*ci]);上得到了一个ArrayIndexOutOfBoundsException。

Answer 1

我最终弄清楚了问题所在。我的转换算法字节数组到int颜色数组是错误的。以下是正确的实施方式。现在，这些图像正在AndroidImageView中正确显示！

/**
* Converts the given <code>MyImageBitmap</code> to the specified image format and returns it as byte array.
*
* @param myImageBitmap the given bitmap, not null
* @param format the given target image format, not null
* @return the converted data in byte array format, not null
*/
private byte[] convert(MyImageBitmap myImageBitmap, String format) {
int width = myImageBitmap.getWidth();
int height = myImageBitmap.getHeight();
byte[] imgRGB888 = myImageBitmap.getPixels();
Bitmap bmp2 = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
int[] colors = new int[width * height];
//We need to convert the image from a byte array to a
// int color array so we can create the Android Bitmap
int r,g,b;
for (int ci = 0; ci < colors.length; ci++) {
r = (int)(0x000000ff & imgRGB888[ci]);
g = (int)(0x000000ff & imgRGB888[ci]);
b = (int)(0x000000ff & imgRGB888[ci]);
colors[ci] = Color.rgb(r, g, b);
}
bmp2.setPixels(colors, 0, width, 0, 0, width, height);
Bitmap.CompressFormat compressFormat;
if (format.equals("jpeg")){
compressFormat = android.graphics.Bitmap.CompressFormat.JPEG;
}else{//must be png
compressFormat = android.graphics.Bitmap.CompressFormat.PNG;
}
try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()){
bmp2.compress(compressFormat, 100, outputStream);
return outputStream.toByteArray();
} catch (IOException e) {
throw new RuntimeException(e);
}
}