android采集视频格式转换算法

  //-----------下面是常用的格式转换方法-----------------------------

    //yv12 转 yuv420p  yvu -> yuv,yuv420p就是I420格式，使用极其广泛
    private void swapYV12toI420(byte[] yv12bytes, byte[] i420bytes, int width, int height) {
        System.arraycopy(yv12bytes, 0, i420bytes, 0, width * height);
        System.arraycopy(yv12bytes, width * height + width * height / 4, i420bytes, width * height, width * height / 4);
        System.arraycopy(yv12bytes, width * height, i420bytes, width * height + width * height / 4, width * height / 4);
    }

    //选择了YUV420SP作为编码的目标颜色空间，其实YUV420SP就是NV12，咱们CAMERA设置的是NV21，所以需要转一下
    private void NV21ToNV12(byte[] nv21, byte[] nv12, int width, int height) {
        if (nv21 == null || nv12 == null) return;
        int framesize = width * height;
        int i = 0, j = 0;
        System.arraycopy(nv21, 0, nv12, 0, framesize);
        for (i = 0; i < framesize; i++) {
            nv12[i] = nv21[i];
        }
        for (j = 0; j < framesize / 2; j += 2) {
            nv12[framesize + j - 1] = nv21[j + framesize];
        }
        for (j = 0; j < framesize / 2; j += 2) {
            nv12[framesize + j] = nv21[j + framesize - 1];
        }
    }

    private void swapYV12toNV12(byte[] yv12bytes, byte[] nv12bytes, int width, int height) {

        int nLenY = width * height;
        int nLenU = nLenY / 4;
        System.arraycopy(yv12bytes, 0, nv12bytes, 0, width * height);
//        for (int i = 0; i < nLenU; i++) {
//            nv12bytes[nLenY + 2 * i] = yv12bytes[nLenY + i];
//            nv12bytes[nLenY + 2 * i + 1] = yv12bytes[nLenY + nLenU + i];
//        }
        for (int i = 0; i < nLenU; i++) {
            nv12bytes[nLenY + 2 * i + 1] = yv12bytes[nLenY + i];
            nv12bytes[nLenY + 2 * i] = yv12bytes[nLenY + nLenU + i];
        }
    }

    private void swapNV12toI420(byte[] nv12bytes, byte[] i420bytes, int width, int height) {

        int nLenY = width * height;
        int nLenU = nLenY / 4;
        System.arraycopy(nv12bytes, 0, i420bytes, 0, width * height);
        for (int i = 0; i < nLenU; i++) {
            i420bytes[nLenY + i] = nv12bytes[nLenY + 2 * i + 1];
            i420bytes[nLenY + nLenU + i] = nv12bytes[nLenY + 2 * i];
        }
    }

    public Bitmap rawByteArray2RGBABitmap2(byte[] data, int width, int height) {
        int frameSize = width * height;
        int[] rgba = new int[frameSize];

        for (int i = 0; i < height; i++)
            for (int j = 0; j < width; j++) {
                int y = (0xff & ((int) data[i * width + j]));
                int u = (0xff & ((int) data[frameSize + (i >> 1) * width + (j & ~1) + 0]));
                int v = (0xff & ((int) data[frameSize + (i >> 1) * width + (j & ~1) + 1]));
                y = y < 16 ? 16 : y;

                int r = Math.round(1.164f * (y - 16) + 1.596f * (v - 128));
                int g = Math.round(1.164f * (y - 16) - 0.813f * (v - 128) - 0.391f * (u - 128));
                int b = Math.round(1.164f * (y - 16) + 2.018f * (u - 128));

                r = r < 0 ? 0 : (r > 255 ? 255 : r);
                g = g < 0 ? 0 : (g > 255 ? 255 : g);
                b = b < 0 ? 0 : (b > 255 ? 255 : b);

                rgba[i * width + j] = 0xff000000 + (b << 16) + (g << 8) + r;
            }

        Bitmap bmp = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        bmp.setPixels(rgba, 0, width, 0, 0, width, height);
        return bmp;
    }