如何在android中将2d int数组转换为位图

Question

我需要将2d整数数组(subSrc)转换为位图.有解决方案吗

    private Bitmap decimation(Bitmap src){
     Bitmap dest = Bitmap.createBitmap(
       src.getWidth(), src.getHeight(), src.getConfig());

     int bmWidth = src.getWidth();
     int bmHeight = src.getHeight();`enter code here`

int[][] subSrc = new int[bmWidth/2][bmWidth/2];
       for(int k = 0; k < bmWidth-2; k++){
        for(int l = 0; l < bmHeight-2; l++){
         subSrc[k][l] = src.getPixel(2*k, 2*l); <---- ??

Answer 1

我找了一个接收二维数组(int [] [])的方法并创建了一个Bitmap,但没有找到,所以我自己写了一个:

public static Bitmap bitmapFromArray(int[][] pixels2d){
    int width = pixels2d.length;
    int height = pixels2d[0].length;
    int[] pixels = new int[width * height];
    int pixelsIndex = 0;
    for (int i = 0; i < width; i++)
    {
        for (int j = 0; j < height; j++)
        {
               pixels[pixelsIndex] = pixels2d[i][j];
               pixelsIndex ++;
        } 
    }
    return Bitmap.createBitmap(pixels, width, height, Bitmap.Config.ARGB_8888);
}

我还写了一个反向方法:

public static int[][] arrayFromBitmap(Bitmap source){
int width = source.getWidth();
int height = source.getHeight();
int[][] result = new int[width][height];
int[] pixels = new int[width*height];
source.getPixels(pixels, 0, width, 0, 0, width, height);
int pixelsIndex = 0;
for (int i = 0; i < width; i++)
{
    for (int j = 0; j < height; j++)
    {
      result[i][j] =  pixels[pixelsIndex];
      pixelsIndex++;
    }
}
return result;
}

希望对你有帮助!

Answer 2

您可以使用 setPixel(int, int, int)或setPixels (int[] Pixels, int offset, int stride, int x, int y, int width, int height)方法位图类。

     Bitmap dest = Bitmap.createBitmap(
       src.getWidth()/2, src.getHeight()/2, src.getConfig());

     int bmWidth = src.getWidth();
     int bmHeight = src.getHeight();


       for(int k = 0; k < bmWidth/2; k++){
        for(int l = 0; l < bmHeight/2; l++){
         dest.setPixel(k,l,src.getPixel(2*k, 2*l));

但我认为这会慢一些。

对于第二种方法，你必须这样做

int subSrc = new int[(bmWidth/2*)(bmHeight/2)];
       for(int k = 0; k < bmWidth-2; k++){
         subSrc[k] = src.getPixel(2*(k/bmWidth), 2*(k%bmHeight)); <---- ??