Android NDK开发 native层获取Surface并显示图像 思路过程

最近参加一个项目，需在 native层获取Surface并显示图像，在网上搜了N多资料

 

总算是找到了相关代码 实现，但是编译连接却是个问题。因为刚学android编程不到一月，而且遇到以前没遇到过的情况。

即 要用到android源代码和库（.so）进行编译链接

 

先把代码贴出来吧

首先是jni层代码 

 

#define TAG "DisplayYUV"
//#define BUFSIZE 720*1038*2
#define BUFSIZE 176*144
#include <string.h>
#include <android/log.h>
#include <jni.h>
#include <android/bitmap.h>
//#include <android/surface.h>
#include <gui/Surface.h>
#include <ui/Region.h>
#include <utils/RefBase.h>
#include <cstdio>
using namespace android;
static sp<Surface> native_surface;
static android::Surface::SurfaceInfo info;
static android::Region dirtyRegion;
char buf[BUFSIZE] = {0};
char * bufYUV = NULL;
FILE *fp = NULL;
jsize len = 0;
extern "C"
{

int setSurface(JNIEnv *env, jobject jsurface, jint version);
void Java_com_example_displayyuv_MainActivity_test(JNIEnv *env, jobject thiz, jobject jsurface)
{
    __android_log_print(ANDROID_LOG_INFO, TAG, "get good cpp test surface!");
    setSurface(env, jsurface, 9);
    //dirtyRegion.set(android::Rect(0x3fff, 0x3fff));
    dirtyRegion.set(android::Rect(0, 0, 176, 144));
    status_t err = native_surface->lock(&info, &dirtyRegion);
    int sformat;
    switch(info.format)
    {
        case PIXEL_FORMAT_RGBA_8888:
        case PIXEL_FORMAT_RGBX_8888:
        case PIXEL_FORMAT_BGRA_8888:
            sformat = 4;
            break;
        case PIXEL_FORMAT_RGB_888:
            sformat = 3;
            break;

        case PIXEL_FORMAT_RGB_565:
        case PIXEL_FORMAT_RGBA_5551:
        case PIXEL_FORMAT_RGBA_4444:
            sformat = 2;
            break;

        default:
            sformat = -1;
    }
    sprintf(buf, "width - %d -- height %d-- format %d---Locked -- %d", info.w, info.h, sformat, err);
    __android_log_print(ANDROID_LOG_INFO, TAG, buf);
    memset(buf, 0x77, BUFSIZE);
    memcpy(info.bits, buf, BUFSIZE);
    //memcpy(info.bits, bufYUV, len);
    native_surface->unlockAndPost();
}


static android::Surface* getNativeSurface(JNIEnv* env, jobject jsurface, jint version)
{
    jclass clazz = env->FindClass("android/view/Surface");
    jfieldID field_surface;
    if(version <=8)
    {
        field_surface = env->GetFieldID(clazz, "mSurface", "I");
    }
    else
        field_surface = env->GetFieldID(clazz, ANDROID_VIEW_SURFACE_JNI_ID, "I");

    if (field_surface == NULL)
    {
        return NULL;
    }
    return (android::Surface *) env->GetIntField(jsurface, field_surface);
}

int setSurface(JNIEnv *env, jobject jsurface, jint version)
{
    native_surface = getNativeSurface(env, jsurface, version);

    if(android::Surface::isValid(native_surface))
    {
        __android_log_print(ANDROID_LOG_INFO, "libjni", "native_surface is valid");
        return 1;
    }
    else
        __android_log_print(ANDROID_LOG_ERROR, "libjni", "native_surface is invalid");

    return 0;
}
void Java_com_example_displayyuv_MainActivity_drawYUV(JNIEnv *env, jobject thiz, jintArray yuvData)
{
    len = env->GetArrayLength(yuvData);
    jint *byteBuf = env->GetIntArrayElements(yuvData, 0);
    bufYUV = (char *)byteBuf;

}
}

 

然后是java层代码

 package com.example.displayyuv;

import java.io.File;
import java.io.FileInputStream;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;

public class MainActivity extends Activity {

    private static final String ACTIVITY_TAG = "displayYUV";
    final String FILE_NAME = "/akiyo_qcif.yuv";
    final int width = 176;
    final int height = 144;
    final int size = (int) (width * height * 1.5);
    byte[] yuvBuffer = new byte[size];
    // final Builder builder = new AlertDialog.Builder(this);

    private SurfaceHolder holder;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // TextView tv = new TextView(this);
        // tv.setText( stringFromJNI() );
        // setContentView(tv);
        // My Code

        Log.v(ACTIVITY_TAG, stringFromJNI());
        SurfaceView surface = (SurfaceView) findViewById(R.id.show);
        // 初始化SurfaceHolder对象
        holder = surface.getHolder();
        holder.addCallback(new Callback() {
            @Override
            public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2,
                    int arg3) {
            }

            @Override
            public void surfaceCreated(SurfaceHolder holder) {
                setVideoSurface(holder.getSurface());
                //test(holder.getSurface());
                if (read(yuvBuffer)) {
                    // 设置对话框的图标
                    // builder.setIcon(R.drawable.tools);
                    // 设置对话框的标题
                    // builder.setTitle("自定义普通对话框");
                    // // 设置对话框显示的内容
                    // builder.setMessage("一个简单的提示对话框");
                    // //创建、并显示对话框
                    // builder.create().show();
                    // }
                    // 锁定整个SurfaceView
//                    Canvas canvas = holder.lockCanvas();
//                    canvas.drawColor(Color.WHITE);
//                    // 绘制背景
//                    // Bitmap back = BitmapFactory.decodeResource(
//                    // SurfaceViewTest.this.getResources(), R.drawable.sun);
//                    // 绘制背景
//                    // canvas.drawBitmap(back, 0, 0, null);
//                    // 绘制完成，释放画布，提交修改
//                    holder.unlockCanvasAndPost(canvas);
//                    yourFunction(yuvBuffer, width, height);
                    // //重新锁一次，"持久化"上次所绘制的内容
                    // holder.lockCanvas(new Rect(0, 0, 0, 0));
                    // holder.unlockCanvasAndPost(canvas);
                    int[] mIntArray = new int[width * height];

                    // Decode Yuv data to integer array
                    // decodeYUV420SP(mIntArray, data, mWidth, mHeight);
                    convertYUV420_NV21toRGB8888(mIntArray, yuvBuffer, width, height);
                    drawYUV(mIntArray);
                    test(holder.getSurface());
                }
            }

            @Override
            public void surfaceDestroyed(SurfaceHolder holder) {
            }
        });
    }

    private boolean read(byte[] yuvArray) {
        try {
            // 如果手机插入了SD卡，而且应用程序具有访问SD的权限
            if (Environment.getExternalStorageState().equals(
                    Environment.MEDIA_MOUNTED)) {
                // 获取SD卡对应的存储目录
                File sdCardDir = Environment.getExternalStorageDirectory();
                // 获取指定文件对应的输入流
                FileInputStream fis = new FileInputStream(
                        sdCardDir.getCanonicalPath() + FILE_NAME);
                fis.read(yuvArray, 0, size);
                return true;
            } else {
                return false;
            }
        }

        catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }

    void yourFunction(byte[] data, int mWidth, int mHeight) {

        int[] mIntArray = new int[mWidth * mHeight];

        // Decode Yuv data to integer array
        // decodeYUV420SP(mIntArray, data, mWidth, mHeight);
        convertYUV420_NV21toRGB8888(mIntArray, data, mWidth, mHeight);

        // Initialize the bitmap, with the replaced color
        Bitmap bmp = Bitmap.createBitmap(mIntArray, mWidth, mHeight,
                Bitmap.Config.ARGB_8888);

        Canvas canvas = holder.lockCanvas();
        canvas.drawBitmap(bmp, 0, 0, null);
        holder.unlockCanvasAndPost(canvas);
        // Draw the bitmap with the replaced color
        // iv.setImageBitmap(bmp);
        // ByteArrayOutputStream out = new ByteArrayOutputStream();
        // YuvImage yuvImage = new YuvImage(data, ImageFormat.NV21, width,
        // height, null);
        // yuvImage.compressToJpeg(new Rect(0, 0, width, height), 50, out);
        // byte[] imageBytes = out.toByteArray();
        // Bitmap bmp = BitmapFactory.decodeByteArray(imageBytes, 0,
        // imageBytes.length);
        // Canvas canvas = holder.lockCanvas();
        // canvas.drawBitmap(bmp, 0, 0, null);
        // holder.unlockCanvasAndPost(canvas);
    }

    static public void decodeYUV420SP(int[] rgba, byte[] yuv420sp, int width,
            int height) {
        final int frameSize = width * height;

        for (int j = 0, yp = 0; j < height; j++) {
            int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;
            for (int i = 0; i < width; i++, yp++) {
                int y = (0xff & ((int) yuv420sp[yp])) - 16;
                if (y < 0)
                    y = 0;
                if ((i & 1) == 0) {
                    v = (0xff & yuv420sp[uvp++]) - 128;
                    u = (0xff & yuv420sp[uvp++]) - 128;
                }

                int y1192 = 1192 * y;
                int r = (y1192 + 1634 * v);
                int g = (y1192 - 833 * v - 400 * u);
                int b = (y1192 + 2066 * u);

                if (r < 0)
                    r = 0;
                else if (r > 262143)
                    r = 262143;
                if (g < 0)
                    g = 0;
                else if (g > 262143)
                    g = 262143;
                if (b < 0)
                    b = 0;
                else if (b > 262143)
                    b = 262143;

                // rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) &
                // 0xff00) | ((b >> 10) & 0xff);
                // rgba, divide 2^10 ( >> 10)
                rgba[yp] = ((r << 14) & 0xff000000) | ((g << 6) & 0xff0000)
                        | ((b >> 2) | 0xff00);
            }
        }
    }

    /**
     * Converts YUV420 NV21 to RGB8888
     * 
     * @param data
     *            byte array on YUV420 NV21 format.
     * @param width
     *            pixels width
     * @param height
     *            pixels height
     * @return a RGB8888 pixels int array. Where each int is a pixels ARGB.
     */
    public static void convertYUV420_NV21toRGB8888(int[] rgba, byte[] data,
            int width, int height) {
        int size = width * height;
        int offset = size;
        // int[] pixels = new int[size];
        int u, v, y1, y2, y3, y4;

        // i percorre os Y and the final pixels
        // k percorre os pixles U e V
        for (int i = 0, k = 0; i < size; i += 2, k += 2) {
            y1 = data[i] & 0xff;
            y2 = data[i + 1] & 0xff;
            y3 = data[width + i] & 0xff;
            y4 = data[width + i + 1] & 0xff;

            u = data[offset + k] & 0xff;
            v = data[offset + k + 1] & 0xff;
            u = u - 128;
            v = v - 128;

            rgba[i] = convertYUVtoRGB(y1, u, v);
            rgba[i + 1] = convertYUVtoRGB(y2, u, v);
            rgba[width + i] = convertYUVtoRGB(y3, u, v);
            rgba[width + i + 1] = convertYUVtoRGB(y4, u, v);

            if (i != 0 && (i + 2) % width == 0)
                i += width;
        }

        // return pixels;
    }

    private static int convertYUVtoRGB(int y, int u, int v) {
        int r, g, b;

        r = y + (int) 1.402f * v;
        g = y - (int) (0.344f * u + 0.714f * v);
        b = y + (int) 1.772f * u;
        r = r > 255 ? 255 : r < 0 ? 0 : r;
        g = g > 255 ? 255 : g < 0 ? 0 : g;
        b = b > 255 ? 255 : b < 0 ? 0 : b;
        return 0xff000000 | (b << 16) | (g << 8) | r;
    }

    // @Override
    // public boolean onCreateOptionsMenu(Menu menu) {
    // // Inflate the menu; this adds items to the action bar if it is present.
    // getMenuInflater().inflate(R.menu.activity_main, menu);
    // return true;
    // }
    public native String stringFromJNI();

    private native void setVideoSurface(Surface surface);

    private native void test(Surface surface);

    private native void test2(Surface surface);
    private native void drawYUV(int[] yuvData);
    static {
        System.loadLibrary("drawSurface");
    }
}

最后是mk文件

 # Copyright (C) 2009 The Android Open Source Project

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

#      http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

#LOCAL_LDFLAGS += -lstdc++

LOCAL_PATH := $(call my-dir)

MY_ANDROID_SOURCE := D:/Android_Source/mydroid

include $(CLEAR_VARS)

LOCAL_LDLIBS :=-llog \

D:/app/libutils.so \

D:/app/libgui.so \

D:/app/libui.so

LOCAL_MODULE    := drawSurface

LOCAL_SRC_FILES := drawSurface.c

LOCAL_SRC_FILES +=  \

invoked.cpp

LOCAL_SHARED_LIBRARIES := \

libskia\

libsurfaceflinger\

    libgui\

    D:/app/libutils\

    D:/app/libgui

LOCAL_C_INCLUDES += \

$(MY_ANDROID_SOURCE)/frameworks/native/include \

$(MY_ANDROID_SOURCE)/system/core/include \

$(MY_ANDROID_SOURCE)/hardware/libhardware/include \

$(JNI_H_INCLUDE)

include $(BUILD_SHARED_LIBRARY)

 

思路呢

一开始在网上找到jni层代码后，开始编译链接

由于Surface的定义在NDK中没有，只有下载安卓源码才行

意识到这个问题也是看了好多篇帖子才转过弯来

 mk文件中一个一个添加上头文件后，又遇到一些函数找不到的问题

怎么办？

先根据提示，看找不到的函数在哪个头文件里，然后去头文件对应的cpp文件所在的文件夹，然后打开该文件夹下的mk文件

看看生成的是哪个库，然后利用adb把模拟器里相应的库pull下来

路径 添加到mk文件中

 总算是弄成功了

虽然特定区域画图还存在问题

 

 思路：

一开始碰到函数找不到，师兄说安卓so里 肯定有

怎么找so，想到mk文件

果然成功

 

一般性总结：

遇到问题，把想到的所以思路都一条一条写下来。

然后一个一个去试。仔细，耐心