Android 虹软人脸识别 学习

文档
https://ai.arcsoft.com.cn/manual/arcface_android_guideV2.html

Bitmap转换成NV21数据

/**
     * Bitmap转化为ARGB数据，再转化为NV21数据
     *
     * @param src    传入的Bitmap，格式为{@link Bitmap.Config#ARGB_8888}
     * @param width  NV21图像的宽度
     * @param height NV21图像的高度
     * @return nv21数据
     */
    public static byte[] bitmapToNv21(Bitmap src, int width, int height) {
        if (src != null && src.getWidth() >= width && src.getHeight() >= height) {
            int[] argb = new int[width * height];
            src.getPixels(argb, 0, width, 0, 0, width, height);
            return argbToNv21(argb, width, height);
        } else {
            return null;
        }
    }

    /**
     * ARGB数据转化为NV21数据
     *
     * @param argb   argb数据
     * @param width  宽度
     * @param height 高度
     * @return nv21数据
     */
    private static byte[] argbToNv21(int[] argb, int width, int height) {
        int frameSize = width * height;
        int yIndex = 0;
        int uvIndex = frameSize;
        int index = 0;
        byte[] nv21 = new byte[width * height * 3 / 2];
        for (int j = 0; j < height; ++j) {
            for (int i = 0; i < width; ++i) {
                int R = (argb[index] & 0xFF0000) >> 16;
                int G = (argb[index] & 0x00FF00) >> 8;
                int B = argb[index] & 0x0000FF;
                int Y = (66 * R + 129 * G + 25 * B + 128 >> 8) + 16;
                int U = (-38 * R - 74 * G + 112 * B + 128 >> 8) + 128;
                int V = (112 * R - 94 * G - 18 * B + 128 >> 8) + 128;
                nv21[yIndex++] = (byte) (Y < 0 ? 0 : (Y > 255 ? 255 : Y));
                if (j % 2 == 0 && index % 2 == 0 && uvIndex < nv21.length - 2) {
                    nv21[uvIndex++] = (byte) (V < 0 ? 0 : (V > 255 ? 255 : V));
                    nv21[uvIndex++] = (byte) (U < 0 ? 0 : (U > 255 ? 255 : U));
                }

                ++index;
            }
        }
        return nv21;
    }

Bitmap转换成BGR数据

/**
         * bitmap转化为bgr数据，格式为{@link Bitmap.Config#ARGB_8888}
         *
         * @param image 传入的bitmap
         * @return bgr数据
         */
        public static byte[] bitmapToBgr(Bitmap image) {
            if (image == null) {
                return null;
            }
            int bytes = image.getByteCount();

            ByteBuffer buffer = ByteBuffer.allocate(bytes);
            image.copyPixelsToBuffer(buffer);
            byte[] temp = buffer.array();
            byte[] pixels = new byte[(temp.length / 4) * 3];
            for (int i = 0; i < temp.length / 4; i++) {
                pixels[i * 3] = temp[i * 4 + 2];
                pixels[i * 3 + 1] = temp[i * 4 + 1];
                pixels[i * 3 + 2] = temp[i * 4];
            }
            return pixels;
        }