public static String format(String format, Object... args) {
    return new Formatter().format(format, args).toString();
}
 
public static boolean hasDebugFlag() {
    String path = Environment.getExternalStorageDirectory() + "/Log/debug"; //文件路径
    FileWriter writer = null;
    try {
        File file = new File(path);
        return file.exists();
    }catch (Exception e) {
 
    }
    return false;
}
 
public static void removeDebugFlag() {
    String path = Environment.getExternalStorageDirectory() + "/Log/debug"; //文件路径
    FileWriter writer = null;
    try {
        File file = new File(path);
        if(file.exists()) {
            file.delete();
        }
    }catch (Exception e) {
 
    }
}
 
public static void writeLog(String fileName,String content) {
    String path = Environment.getExternalStorageDirectory() + "/Log/"; //文件路径
    FileWriter writer = null;
    try {
        File file = new File(path);
        if (!file.exists()) {  //没有创建文件夹则创建
            file.mkdirs();
        }
        Date currentTime = new Date();
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String dateString = formatter.format(currentTime);
        // 打开一个写文件器，构造函数中的第二个参数true表示以追加形式写文件
        writer = new FileWriter(path + fileName, true);
        writer.write(dateString + " " + content + "\r\n");
        writer.flush();
        if (writer != null) {
            //关闭流
            writer.close();
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
}
 
public static boolean saveBitmap(Bitmap bitmap, Long id) {
    if (bitmap == null)
        return false;
 
    String path = Environment.getExternalStorageDirectory() + "/Log/";
    FileOutputStream fos = null;
    try {
        File f = new File(path +id.toString() + ".png");
        if(f.exists()) {
            f.delete();
        }
        f.createNewFile();
        fos = new FileOutputStream(f);
        bitmap.compress(Bitmap.CompressFormat.PNG, 100, fos);
        fos.flush();
        return true;
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (fos != null) {
            try {
                fos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    return false;
}
 
public void dumpFrame(ImiDevice.ImiFrame nextFrame, Long id) {
    try{
        ByteBuffer frameData = nextFrame.getData();
        int width = nextFrame.getWidth();
        int height = nextFrame.getHeight();
        frameData.position(0);
        int length = frameData.remaining();
        byte[] buf = new byte[length];
        frameData.get(buf);
        Bitmap save = com.commaai.face.util.Utils.RGB2Bitmap(buf, width, height);
        saveBitmap(save, id);
    }catch (Exception e) {
        writeLog("brokenflow.txt", "failed to save bitmap");
    }
}
 
使用逻辑
if(hasDebugFlag()) {
    dumpcnt = 20;
    removeDebugFlag();
}
 
if(dumpcnt > 0) {
    dumpcnt--;
    total++;
    dumpFrame(nextFrame, total);
}