处理视频流byte数据

android端代码：

Parameters parameters = cam.getParameters();     Integer width = parameters.getPreviewSize().width;    Integer height = parameters.getPreviewSize().height;    Log.i("preview size: ", String.valueOf(width) + "x" + String.valueOf(height));    int[] mIntArray = new int[width*height];    // Decode Yuv data to integer array    decodeYUV420SP(mIntArray, data, width, height);    //Initialize the bitmap, with the replaced color      Bitmap bmp = Bitmap.createBitmap(mIntArray, width, height, Bitmap.Config.ARGB_8888);      saveImage(bmp);

这是decodeYUV方法：

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);        }    }    }

方法二：

static public void encodeYUV420SP_original(byte[] yuv420sp, int[] rgba,        int width, int height) {    final int frameSize = width * height;    int[] U, V;    U = new int[frameSize];    V = new int[frameSize];    final int uvwidth = width / 2;    int r, g, b, y, u, v;    for (int j = 0; j < height; j++) {        int index = width * j;        for (int i = 0; i < width; i++) {            r = (rgba[index] & 0xff000000) >> 24;            g = (rgba[index] & 0xff0000) >> 16;            b = (rgba[index] & 0xff00) >> 8;            // rgb to yuv            y = (66 * r + 129 * g + 25 * b + 128) >> 8 + 16;            u = (-38 * r - 74 * g + 112 * b + 128) >> 8 + 128;            v = (112 * r - 94 * g - 18 * b + 128) >> 8 + 128;            // clip y            yuv420sp[index++] = (byte) ((y < 0) ? 0 : ((y > 255) ? 255 : y));            U[index] = u;            V[index++] = v;        }    }

方法三：

static public void decodeYUV420SP(int[] rgba, byte[] yuv420sp, int width,                              int height) {    final int frameSize = width * height;    int r, g, b, y1192, y, i, uvp, u, v;    for (int j = 0, yp = 0; j < height; j++) {        uvp = frameSize + (j >> 1) * width;        u = 0;        v = 0;        for (i = 0; i < width; i++, yp++) {            y = (0xff & ((int) yuv420sp[yp])) - 16;            if (y < 0)                y = 0;            if ((i & 1) == 0) {            // above answer is wrong at the following lines. just swap ***u*** and ***v***                 u = (0xff & yuv420sp[uvp++]) - 128;                v = (0xff & yuv420sp[uvp++]) - 128;            }            y1192 = 1192 * y;            r = (y1192 + 1634 * v);            g = (y1192 - 833 * v - 400 * u);            b = (y1192 + 2066 * u);            r = Math.max(0, Math.min(r, 262143));            g = Math.max(0, Math.min(g, 262143));            b = Math.max(0, Math.min(b, 262143));            // combine ARGB            rgba[yp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) & 0xff00)                    | ((b >> 10) | 0xff);        }    }}

方法三有人评论说：

最后一行似乎有问题：（（g >> 2 6）＆0xff00 |（（b >> 10）| 0xff）不应该是（（g >> 2）＆0xff00）|（ （b >> 10）＆0xff）？

方法四：

// decode Y, U, and V values on the YUV 420 buffer described as YCbCr_422_SP by Android // David Manpearl 081201 public void decodeYUV(int[] out, byte[] fg, int width, int height)        throws NullPointerException, IllegalArgumentException {    int sz = width * height;    if (out == null)        throw new NullPointerException("buffer out is null");    if (out.length < sz)        throw new IllegalArgumentException("buffer out size " + out.length                + " < minimum " + sz);    if (fg == null)        throw new NullPointerException("buffer 'fg' is null");    if (fg.length < sz)        throw new IllegalArgumentException("buffer fg size " + fg.length                + " < minimum " + sz * 3 / 2);    int i, j;    int Y, Cr = 0, Cb = 0;    for (j = 0; j < height; j++) {        int pixPtr = j * width;        final int jDiv2 = j >> 1;        for (i = 0; i < width; i++) {            Y = fg[pixPtr];            if (Y < 0)                Y += 255;            if ((i & 0x1) != 1) {                final int cOff = sz + jDiv2 * width + (i >> 1) * 2;                Cb = fg[cOff];                if (Cb < 0)                    Cb += 127;                else                    Cb -= 128;                Cr = fg[cOff + 1];                if (Cr < 0)                    Cr += 127;                else                    Cr -= 128;            }            int R = Y + Cr + (Cr >> 2) + (Cr >> 3) + (Cr >> 5);            if (R < 0)                R = 0;            else if (R > 255)                R = 255;            int G = Y - (Cb >> 2) + (Cb >> 4) + (Cb >> 5) - (Cr >> 1)                    + (Cr >> 3) + (Cr >> 4) + (Cr >> 5);            if (G < 0)                G = 0;            else if (G > 255)                G = 255;            int B = Y + Cb + (Cb >> 1) + (Cb >> 2) + (Cb >> 6);            if (B < 0)                B = 0;            else if (B > 255)                B = 255;            out[pixPtr++] = 0xff000000 + (B << 16) + (G << 8) + R;        }    }}

方法五：（发布的人说转换的颜色挺正）

static public void decodeYUV420SP(int[] rgb, 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);        }    }}

方法六：将YUV图像转换为RGB的图像，在ndk中操作(作者说处理480*320需要0~25ms)

void toRGB565（unsigned short * yuvs，int widthIn，int heightIn，unsigned int * rgbs，int widthOut，int heightOut）{  int half_widthIn = widthIn >> 1;  //亮度数据的结束  int lumEnd =（widthIn * heightIn）>> 1;  //指向下一个亮度值对  int lumPtr = 0;  //指向下一个色度值对  int chrPtr = lumEnd;  //当前亮度扫描线的结束  int lineEnd = half_widthIn;  int x，y;  for（y = 0; y> 1;    for（x = 0; x> 8）＆0xff;      Y1 = Y1＆0xff;      int Cr = yuvs [chrPtr ++];      int Cb =（（Cr >> 8）＆0xff） -  128;      Cr =（Cr＆0xff） -  128;      int R，G，B;      //生成第一个RGB组件      B = Y1 +（（454 * Cb）>> 8）;      如果（B <0）B = 0; 如果（B> 255）B = 255;      G = Y1  - （（88 * Cb + 183 * Cr）>> 8）;      如果（G <0）G = 0; 如果（G> 255）G = 255;      R = Y1 +（（359 * Cr）>> 8）;      如果（R 0）R = 0; 如果（R> 255）R = 255;      int val =（（R＆0xf8）<< 8）| （（G＆0xfc）<< 3）| （B >> 3）;      //生成第二个RGB组件      B = Y1 +（（454 * Cb）>> 8）;      如果（B <0）B = 0; 如果（B> 255）B = 255;      G = Y1  - （（88 * Cb + 183 * Cr）>> 8）;      如果（G <0）G = 0; 如果（G> 255）G = 255;      R = Y1 +（（359 * Cr）>> 8）;      如果（R 0）R = 0; 如果（R> 255）R = 255;      rgbs [yPosOut + x] = val | （（（R＆0xf8）<< 8）|（（G＆0xfc）<< 3）|（B >> 3））<< 16）;    }    //必要时跳回到色度值的开头    chrPtr = lumEnd +（（lumPtr >> 1）/ half_widthIn）* half_widthIn;    lineEnd + = half_widthIn;  }}

/ ** *将输入图像从YUV转换为RGB 5_6_5图像。 *输出缓冲区的大小必须至少为输入图像的大小。 * /JNIEXPORT void JNICALL Java_de_offis_magic_core_NativeWrapper_image2TextureColor  （JNIEnv * env，jclass clazz，  jbyteArray imageIn，jint widthIn，jint heightIn，  jobject imageOut，jint widthOut，jint heightOut，  jint过滤器）{jbyte * cImageIn =（* env） - > GetByteArrayElements（env，imageIn，NULL）;jbyte * cImageOut =（jbyte *）（* env） - > GetDirectBufferAddress（env，imageOut）;toRGB565（（unsigned short *）cImageIn，widthIn，heightIn，（unsigned int *）cImageOut，widthOut，heightOut）;（* env） - > ReleaseByteArrayElements（env，imageIn，cImageIn，JNI_ABORT）;}

这下面是一个jni接口函数

jintArray Java_com_spore_ImageUtilEngine_decodeYUV420SP(JNIEnv * env,jobject thiz, jbyteArray buf, jint width, jint height) {jbyte * yuv420sp = (*env)->GetByteArrayElements(env, buf, 0);int frameSize = width * height;jint rgb[frameSize]; // 鏂板浘鍍忓儚绱犲��initTable();int i = 0, j = 0,yp = 0;int uvp = 0, u = 0, v = 0;for (j = 0, yp = 0; j < height; j++){uvp = frameSize + (j >> 1) * width;u = 0;v = 0;for (i = 0; i < width; i++, yp++){int y = (0xff & ((int) yuv420sp[yp]));if (y < 0)y = 0;if ((i & 1) == 0){v = (0xff & yuv420sp[uvp++]);u = (0xff & yuv420sp[uvp++]);}//int y1192 = 1192 * y;//int r = (y1192 + 1634 * v);//int g = (y1192 - 833 * v - 400 * u);//int b = (y1192 + 2066 * u);int y1192 = y_table[y];int r = r_yv_table[y][v];//(y1192 + r_v_table[v]);int g = (y1192 - g_v_table[v] - g_u_table[u]);int b = b_yu_table[y][u];//(y1192 + b_u_table[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;//r = (r >> 31) ? 0 : (r & 0x3ffff);//g = (g >> 31) ? 0 : (g & 0x3ffff);//b = (b >> 31) ? 0 : (b & 0x3ffff);rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);}}jintArray result = (*env)->NewIntArray(env, frameSize);(*env)->SetIntArrayRegion(env, result, 0, frameSize, rgb);(*env)->ReleaseByteArrayElements(env, buf, yuv420sp, 0);return result;}

这里附上本人修改的，对byte数据进行裁剪所需要的区域。

注意：代码中width和height分别代表原图的宽和高

//====方法五：竖直方向裁剪int outGrey[width*800];jint *bb=outGrey;int frameSize = width * height;for (int j = 200, yp = 200*width,cp=0; j < 1000; j++) {int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;for (int i = 0; i < width; i++, yp++, cp++) {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;  outGrey[cp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);  }  }

竖直裁剪的效果图

//====方法五： 直接裁剪byte数据int cutW = width / 6;   //裁剪宽度int cutX = width / 2 - width / 12;   //裁剪宽度起始点int outGrey[cutW * height];jint *bb = outGrey;int frameSize = width * height;for (int j = 0, yp = cutX, cp = 0; j < height; j++) {int uvp = frameSize + (j >> 1) * width+ cutX, u = 0, v = 0;for (int i = cutX; i < cutX+ cutW; i++, yp++, cp++) {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;outGrey[cp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);}yp += (width- cutW);}