在Andorid中使用FFmpeg实现YUV解码为BMP
在Andorid中使用FFmpeg实现YUV解码为BMP
最进根据公司项目需要，学习FFmpeg音视频编解码做技术储备，项目是运行在android平台上的，现在需求还不确定，可能需要YUV解码为BMP。
activity_main.xml主要代码
bt_yuv打开文件管理器选择文件，tv_route_5显示文件路径，bt6开始解码，rv展示解码后的数据。
MainActivity.java 核心代码
static {
System.loadLibrary("native-lib");
}
/**
* yuv转换成bmp
* @param input_jstr 输入的路径
* @param output_jstr 输出路径
* @param w_jstr 宽
* @param h_jstr 高
* @return
*/
public native int yuvToBitmap(String input_jstr, String output_jstr, int w_jstr, int h_jstr);
在Android中使用FFmpeg可以参考 在Android Studio中使用cmake编译FFmpeg
/**
* 调用系统文件管理器
*
* @param type
*/
public void openSystemFile(int type) {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
//系统调用Action属性
intent.setType("*/*");
//设置文件类型
intent.addCategory(Intent.CATEGORY_OPENABLE);
// 添加Category属性
try {
startActivityForResult(intent, type);
} catch (Exception e) {
Toast.makeText(this, "没有正确打开文件管理器", Toast.LENGTH_SHORT).show();
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK) {//是否选择，没选择就不会继续
if (requestCode == 4) {
tvRoute4.setText(videoPath);
} else {
Uri uri = data.getData();//得到uri，后面就是将uri转化成file的过程。
String[] proj = {MediaStore.Images.Media.DATA};
Cursor actualimagecursor = managedQuery(uri, proj, null, null, null);
int actual_image_column_index = actualimagecursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
actualimagecursor.moveToFirst();
String img_path = actualimagecursor.getString(actual_image_column_index);
if (img_path.endsWith(".yuv")) {
if (requestCode == 5) {
tvRoute5.setText(img_path);
}
} else {
Toast.makeText(this, "请选择正确的文件", Toast.LENGTH_SHORT).show();
}
}
}
}
/**
* 把YUV格式的视频解析成BMP
*/
private void conversionYUV(final TextView tvRoute, final int w_jstr, final int h_jstr) {
dialog.showDialog();
String[] videoInfo = tvRoute.getText().toString().split("/");
String fileName = videoInfo[videoInfo.length - 1];
final String[] fileNames = fileName.split("\\.");
new Thread(new Runnable() {
public void run() {
picNum = yuvToBitmap(tvRoute.getText().toString(), "/storage/emulated/0/Download/avtest/" + fileNames[0] + ".rgb", w_jstr, h_jstr);
//成功
if (picNum >= 0) {
handler.sendEmptyMessage(0);
} else {
handler.sendEmptyMessage(1);
}
}
}).start();
}
Handler handler = new Handler(new Handler.Callback() {
@Override
public boolean handleMessage(Message message) {
if (message.what == 0) {
dealResult();
} else if (message.what == 1) {
Toast.makeText(MainActivity.this, "Error", Toast.LENGTH_SHORT).show();
dialog.dismiss();
}
return false;
}
});
/**
* 刷新RV，展示解析的数据
*/
private void dealResult() {
for (int i = 0; i < picNum; i++) {
dataImage.add("/storage/emulated/0/Download/avtest/img/_" + i + ".bmp");
}
adapterImage.notifyDataSetChanged();
dialog.dismiss();
}
打开文件管理器，选择YUV文件，在子线程中调用yuvToBitmap方法进行解码，在Handler中更新UI。
native-lib.cpp核心代码
/**
* RGB数据->BMP
* @param rgb24_buffer
* @param width
* @param height
* @param index
* @return
*/
int SaveAsBMP(uint8_t *rgb24_buffer, int width, int height, int index) {
typedef struct {
long imageSize;
long blank;
long startPosition;
} BmpHead;
typedef struct {
long Length;
long width;
long height;
unsigned short colorPlane;
unsigned short bitColor;
long zipFormat;
long realSize;
long xPels;
long yPels;
long colorUse;
long colorImportant;
} InfoHead;
int i = 0, j = 0;
BmpHead m_BMPHeader = {0};
InfoHead m_BMPInfoHeader = {0};
char bfType[2] = {'B', 'M'};
int header_size = sizeof(bfType) + sizeof(BmpHead) + sizeof(InfoHead);
// unsigned char *rgb24_buffer = NULL;
FILE *fp_bmp = NULL;
char *filename = new char[255]; //文件存放路径，根据自己的修改
sprintf(filename, "%s_%d.bmp", "/storage/emulated/0/Download/avtest/img/", index);
// if ((fp_rgb24 = fopen(rgb24path, "rb")) == NULL) {
// printf("Error: Cannot open input RGB24 file.\n");
// return -1;
// }
if ((fp_bmp = fopen(filename, "wb")) == NULL) {
printf("Error: Cannot open output BMP file.\n");
return -1;
}
// rgb24_buffer = (unsigned char *) malloc(width * height * 3);
// fread(rgb24_buffer, 1, width * height * 3, str);
m_BMPHeader.imageSize = 3 * width * height + header_size;
m_BMPHeader.startPosition = header_size;
m_BMPInfoHeader.Length = sizeof(InfoHead);
m_BMPInfoHeader.width = width;
//BMP storage pixel data in opposite direction of Y-axis (from bottom to top).
m_BMPInfoHeader.height = -height;
m_BMPInfoHeader.colorPlane = 1;
m_BMPInfoHeader.bitColor = 24;
m_BMPInfoHeader.realSize = 3 * width * height;
fwrite(bfType, 1, sizeof(bfType), fp_bmp);
fwrite(&m_BMPHeader, 1, sizeof(m_BMPHeader), fp_bmp);
fwrite(&m_BMPInfoHeader, 1, sizeof(m_BMPInfoHeader), fp_bmp);
//BMP save R1|G1|B1,R2|G2|B2 as B1|G1|R1,B2|G2|R2
//It saves pixel data in Little Endian
//So we change 'R' and 'B'
for (j = 0; j < height; j++) {
for (i = 0; i < width; i++) {
char temp = rgb24_buffer[(j * width + i) * 3 + 2];
rgb24_buffer[(j * width + i) * 3 + 2] = rgb24_buffer[(j * width + i) * 3 + 0];
rgb24_buffer[(j * width + i) * 3 + 0] = temp;
}
}
fwrite(rgb24_buffer, 3 * width * height, 1, fp_bmp);
fclose(fp_bmp);
return 0;
}
/***
* yuv转换成bmp
*/
extern "C"
JNIEXPORT jint JNICALL
Java_com_yodosmart_ffmpegdemo_MainActivity_yuvToBitmap(JNIEnv *env, jobject instance,
jstring input_jstr_, jstring output_jstr_,
jint w_jstr, jint h_jstr) {
const char *input_jstr = env->GetStringUTFChars(input_jstr_, 0);
const char *output_jstr = env->GetStringUTFChars(output_jstr_, 0);
//Parameters
FILE *src_file = fopen(input_jstr, "rb");
const int src_w = w_jstr, src_h = h_jstr;
AVPixelFormat src_pixfmt = AV_PIX_FMT_YUV420P;
int src_bpp = av_get_bits_per_pixel(av_pix_fmt_desc_get(src_pixfmt));
FILE *dst_file = fopen(output_jstr, "wb");
const int dst_w = w_jstr, dst_h = h_jstr;
AVPixelFormat dst_pixfmt = AV_PIX_FMT_RGB24;
int dst_bpp = av_get_bits_per_pixel(av_pix_fmt_desc_get(dst_pixfmt));
//Structures
uint8_t *src_data[4];
int src_linesize[4];
uint8_t *dst_data[4];
int dst_linesize[4];
int rescale_method = SWS_BICUBIC;
struct SwsContext *img_convert_ctx;
uint8_t *temp_buffer = (uint8_t *) malloc(src_w * src_h * src_bpp / 8);
int frame_idx = 0;
int ret = 0;
ret = av_image_alloc(src_data, src_linesize, src_w, src_h, src_pixfmt, 1);
if (ret < 0) {
printf("Could not allocate source image\n");
return -1;
}
ret = av_image_alloc(dst_data, dst_linesize, dst_w, dst_h, dst_pixfmt, 1);
if (ret < 0) {
printf("Could not allocate destination image\n");
return -1;
}
//-----------------------------
//Init Method 1
img_convert_ctx = sws_alloc_context();
//Show AVOption
// av_opt_show2(img_convert_ctx, stdout, AV_OPT_FLAG_VIDEO_PARAM, 0);
//Set Value
// av_opt_set_int(img_convert_ctx, "sws_flags", SWS_BICUBIC | SWS_PRINT_INFO, 0);
av_opt_set_int(img_convert_ctx, "srcw", src_w, 0);
av_opt_set_int(img_convert_ctx, "srch", src_h, 0);
av_opt_set_int(img_convert_ctx, "src_format", src_pixfmt, 0);
//'0' for MPEG (Y:0-235);'1' for JPEG (Y:0-255)
av_opt_set_int(img_convert_ctx, "src_range", 1, 0);
av_opt_set_int(img_convert_ctx, "dstw", dst_w, 0);
av_opt_set_int(img_convert_ctx, "dsth", dst_h, 0);
av_opt_set_int(img_convert_ctx, "dst_format", dst_pixfmt, 0);
av_opt_set_int(img_convert_ctx, "dst_range", 1, 0);
sws_init_context(img_convert_ctx, NULL, NULL);
//Init Method 2
//img_convert_ctx = sws_getContext(src_w, src_h,src_pixfmt, dst_w, dst_h, dst_pixfmt,
// rescale_method, NULL, NULL, NULL);
//-----------------------------
/*
//Colorspace
ret=sws_setColorspaceDetails(img_convert_ctx,sws_getCoefficients(SWS_CS_ITU601),0,
sws_getCoefficients(SWS_CS_ITU709),0,
0, 1 << 16, 1 << 16);
if (ret==-1) {
printf( "Colorspace not support.\n");
return -1;
}
*/
while (1) {
if (fread(temp_buffer, 1, src_w * src_h * src_bpp / 8, src_file) !=
src_w * src_h * src_bpp / 8) {
break;
}
switch (src_pixfmt) {
case AV_PIX_FMT_GRAY8: {
memcpy(src_data[0], temp_buffer, src_w * src_h);
break;
}
case AV_PIX_FMT_YUV420P: {
memcpy(src_data[0], temp_buffer, src_w * src_h); //Y
memcpy(src_data[1], temp_buffer + src_w * src_h, src_w * src_h / 4); //U
memcpy(src_data[2], temp_buffer + src_w * src_h * 5 / 4, src_w * src_h / 4); //V
break;
}
case AV_PIX_FMT_YUV422P: {
memcpy(src_data[0], temp_buffer, src_w * src_h); //Y
memcpy(src_data[1], temp_buffer + src_w * src_h, src_w * src_h / 2); //U
memcpy(src_data[2], temp_buffer + src_w * src_h * 3 / 2, src_w * src_h / 2); //V
break;
}
case AV_PIX_FMT_YUV444P: {
memcpy(src_data[0], temp_buffer, src_w * src_h); //Y
memcpy(src_data[1], temp_buffer + src_w * src_h, src_w * src_h); //U
memcpy(src_data[2], temp_buffer + src_w * src_h * 2, src_w * src_h); //V
break;
}
case AV_PIX_FMT_YUYV422: {
memcpy(src_data[0], temp_buffer, src_w * src_h * 2); //Packed
break;
}
case AV_PIX_FMT_RGB24: {
memcpy(src_data[0], temp_buffer, src_w * src_h * 3); //Packed
break;
}
default: {
printf("Not Support Input Pixel Format.\n");
break;
}
}
sws_scale(img_convert_ctx, (const uint8_t *const *) src_data, src_linesize, 0, src_h,
dst_data, dst_linesize);
printf("Finish process frame %5d\n", frame_idx);
switch (dst_pixfmt) {
case AV_PIX_FMT_GRAY8: {
fwrite(dst_data[0], 1, dst_w * dst_h, dst_file);
break;
}
case AV_PIX_FMT_YUV420P: {
fwrite(dst_data[0], 1, dst_w * dst_h, dst_file); //Y
fwrite(dst_data[1], 1, dst_w * dst_h / 4, dst_file); //U
fwrite(dst_data[2], 1, dst_w * dst_h / 4, dst_file); //V
break;
}
case AV_PIX_FMT_YUV422P: {
fwrite(dst_data[0], 1, dst_w * dst_h, dst_file); //Y
fwrite(dst_data[1], 1, dst_w * dst_h / 2, dst_file); //U
fwrite(dst_data[2], 1, dst_w * dst_h / 2, dst_file); //V
break;
}
case AV_PIX_FMT_YUV444P: {
fwrite(dst_data[0], 1, dst_w * dst_h, dst_file); //Y
fwrite(dst_data[1], 1, dst_w * dst_h, dst_file); //U
fwrite(dst_data[2], 1, dst_w * dst_h, dst_file); //V
break;
}
case AV_PIX_FMT_YUYV422: {
fwrite(dst_data[0], 1, dst_w * dst_h * 2, dst_file); //Packed
break;
}
case AV_PIX_FMT_RGB24: {
fwrite(dst_data[0], 1, dst_w * dst_h * 3, dst_file); //Packed
SaveAsBMP(dst_data[0], src_w, src_h, frame_idx);
break;
}
case AV_PIX_FMT_BGR24: {
fwrite(dst_data[0], 1, dst_w * dst_h * 3, dst_file); //Packed
SaveAsBMP(dst_data[0], src_w, src_h, frame_idx);
break;
}
default: {
printf("Not Support Output Pixel Format.\n");
break;
}
}
frame_idx++;
}
sws_freeContext(img_convert_ctx);
free(temp_buffer);
fclose(dst_file);
av_freep(&src_data[0]);
av_freep(&dst_data[0]);
return frame_idx;
}
分为两个部分：
- 将YUV数据解析为RGB数据
- 将RGB数据解析为BMP
对应上面代码中的两个函数
注意： RGB和BGR的转换
代码下载
参考资料
http://blog.csdn.net/leixiaohua1020/article/details/42134965
http://blog.csdn.net/leixiaohua1020/article/details/50534150
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