YUV420与YUV444互转，YUV420与YUV444读取和保存，YUV的显示和播放功能

以你之姓@ 2022-05-14 09:47 248阅读 0赞

# YUV420与YUV444互转，YUV420与YUV444读取和保存，YUV的显示和播放功能 #

--------------------

【[尊重原创，转载请注明出处][Link 1]】：[https://blog.csdn.net/guyuealian/article/details/82454945][Link 1]

OpenCV提供了RGB与YUV420/YUV444互转的接口：***cvtColor***()，但根尴尬OpenCV就是没有提供YUV444与YUV420互转的接口，如果你想用OpenCV转换，那就只能使用间接的方法了，将YUV420转为BGR（*CV\_YUV2BGR\_I420*），然后再将BGR转为YUV444（*CV\_BGR2YUV*），这很蛋疼！效率太低了。

实质上，只要我们理解了YUV420与YUV444的数据格式，完全可以自己转换的，下面使用C++实现YUV420与YUV444读取和保存，以及UV420与YUV444互转，并实现YUV的显示和播放功能。

YUV444和YUV420的测试文件，可以这里[下载][Link 2]：[https://download.csdn.net/download/guyuealian/10697442][Link 2]

--------------------

**目录**

C++读写YUV444和YUV420，现实YUV444与YUV420互转，支持OpenCV显示

一、YUV数据格式

1、YUV分三种采样方式：

2、YUV的存储格式：

二、YUV文件的读取和保存

1、读取YUV文件

2、保存YUV文件

三、C++实现YUV420与YUV444互转

1、YUV420转YUV444

2、YUV444转YUV420

四、显示和播放YUV文件

1、显示YUV图像

2、播放YUV数据

五、完整的代码

参考资料：

--------------------

## 一、YUV数据格式 ##

YUV有三个分量：Y（Luminance/Luma：亮度）、U和V表示色差，体现的是图片的色彩信息。相对于RGB彩色空间，将亮度信息和色彩信息分离。这种编码模式也更加适应于人眼，据研究表明，人眼对亮度信息比色彩信息更加敏感。而YUV下采样就是根据人眼的特点，将人眼相对不敏感的色彩信息进行压缩采样，得到相对小的文件进行播放和传输。与YUV相像YCbCr其实与其有少许不同，体现在参数的大小上，本质上都是将亮度信息与色彩信息相分开。

--------------------

### 1、YUV分三种采样方式： ###

![20161106110000210][]

>     YUV444：对于每一个像素都对应一个Y分量、一个U分量、一个V分量。
> 
>     YUV422：对于一个像素都对应一个Y分量，但是每两个像素（或者说Y分量）对应一个U分量和一个V分量。
> 
>     YUV420：对于一个像素都对应一个Y分量，但是每四个像素（或者说Y分量）对应一个U分量和一个V分量。

### 2、YUV的存储格式： ###

YUYUV在存储时是以数组的形式存储的，可以看做连续的三个一维数组。三个数组分别单独存储Y、U、V分量。以一幅100×100的YUV444图像为例，下图表示的**YUV444的存储格式**和**YUV420的存储格式**。

![70][]

从总数据量来看，YUV444需要存储100×100×3个值，YUV422需要存储100×100×2个值，YUV420需要存储100×100×3/2个值。

--------------------

## 二、YUV文件的读取和保存 ##

### 1、读取YUV文件 ###

YUV文件实质上是保存了图像的YUV格式的原始数据，并没有像png、jpg等图像格式对图像的数据进行压缩。这也就是为什么，YUV格式的文件普遍大比较大了。既然 YUV文件是未经压缩的原始数据，那读取和保存YUV文件就十分简单了。**基本方法是**：**只需要调用C++的fopen()函数打开YUV文件获得指向该流的[文件指针][Link 3]，然后使用*fread()*从文件流中直接读取YUV的数据即可。**

下面是实现读取YUV444和YUV420的完整代码：

/*********************************************************	
    	@brief         : 读取yuv图像文件,若输入的是多帧的图像文件,如yuv视频文件,则返回最后一帧的数据
    	@param fileYUV : YUV文件
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : unsigned char* 返回YUV数据
    	********************************************************/	
        unsigned char* read_yuvImage(string fileYUV, int w, int h, ColorSpace colorType) {
    		FILE * pFileIn;      //输入CS_YUV444文件
    		if (NULL == (pFileIn = fopen(fileYUV.c_str(), "rb"))) {
    			printf("File input is can't open!\n");
    			fclose(pFileIn);
    			return nullptr;
    		}
    		int bufLen = 0;
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			bufLen = w * h * 3;
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			bufLen = w*h * 3 / 2;
    		}
    		unsigned char* yuvBuf = new unsigned char[bufLen];
    		//fread(yuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn);//返回第一帧
    		while (fread(yuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn))//返回最后一帧
    		{
    		}
    		fclose(pFileIn);
    		return yuvBuf;
    	}

注意这里定义一个枚举类型***ColorSpace***：

enum ColorSpace {
    		CS_YUV444,
    		CS_YUV420
    	};

> **说明：**
> 
>     上面read\_yuvImage函数若输入的是多帧的图像文件,如yuv视频文件,则返回最后一帧的YUV数据，当然了，你稍微改改就可以实现读取每一帧YUV数据了。下面章节会增加显示YUV数据部分，会借助OpenCV实现播放YUV的视频文件。

--------------------

### 2、保存YUV文件 ###

保存YUV文件也十分简单，**调用C++的fopen()函数打开YUV文件获得指向该流的[文件指针][Link 3]，然后使用*fwrite()*把YUV的数据流保存到打开的文件即可。**

下面是实现保存YUV444和YUV420数据的完整代码：

/*********************************************************
    	@brief         : 保存YUV数据流
    	@param fileYUV : 输出YUV文件的路径
    	@param inbuf   : 需要保存的YUV数据流
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : void
    	********************************************************/
    	void write_yuvImage(string fileYUV, unsigned char* inframe, int w, int h, ColorSpace colorType) {
    		FILE * pFileOut;     //输出YUV文件
    		if (NULL == (pFileOut = fopen(fileYUV.c_str(), "wb"))) {
    			printf("File output is can't open!\n");
    			fclose(pFileOut);
    			return;
    		}
    		int bufLen = 0;
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			bufLen = w * h * 3;
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			bufLen = w*h * 3 / 2;
    		}
    		fwrite(inframe, bufLen * sizeof(unsigned char), 1, pFileOut);
    		fclose(pFileOut);
    	}

--------------------

## 三、C++实现YUV420与YUV444互转 ##

OpenCV提供了RGB与YUV420/YUV444互转的接口：***cvtColor***()，但根尴尬OpenCV就是没有提供YUV444与YUV420互转的接口，如果你想用OpenCV转换，那就只能间接的方法了，将YUV420转为BGR（*CV\_YUV2BGR\_I420*），然后再将BGR转为YUV444（*CV\_BGR2YUV*），这很蛋疼！效率太低了。

实质上，只要我们理解了YUV420与YUV444的数据格式，完全可以自己转换的，下面使用C++实现YUV420与YUV444互转，这部分不依赖OpenCV，因此效率十分高的！！！

--------------------

### 1、YUV420转YUV444 ###

YUV420转YUV444，实际就是对UV两个分量色度进行上采样，最为简单的实现思路是直接填充。

以U分量为例，其序列如下

![20161107104721573][]

对U进行插值，每个田字格四个位置使用一个U值。

![20161107104831294][]

在代码中，可以直接通过对数组循环赋值即可完成。对V分量的操作相同。 填充方式实现简单，但效果较差，一般可以通过插值来完成上采样。

下面是C++实现YUV420转YUV444的代码：

void YUV420TOYUV444(unsigned char *inbuf, unsigned char *outbuf, int w, int h) {
    		unsigned char *srcY = NULL, *srcU = NULL, *srcV = NULL;
    		unsigned char *desY = NULL, *desU = NULL, *desV = NULL;
    		srcY = inbuf;//Y
    		srcU = srcY + w * h;//U
    		srcV = srcU + w * h / 4;;//V
    
    		desY = outbuf;
    		desU = desY + w * h;
    		desV = desU + w * h;
    		memcpy(desY, srcY, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    	   //UV分量转换
    		int i, j;
    		for (i = 0; i < h; i += 2) {//行
    			for (j = 0; j < w; j += 2) {//列
    										//U
    				desU[i*w + j] = srcU[i / 2 * w / 2 + j / 2];
    				desU[i*w + j + 1] = srcU[i / 2 * w / 2 + j / 2];
    				desU[(i + 1)*w + j] = srcU[i / 2 * w / 2 + j / 2];
    				desU[(i + 1)*w + j + 1] = srcU[i / 2 * w / 2 + j / 2];
    				//V
    				desV[i*w + j] = srcV[i / 2 * w / 2 + j / 2];
    				desV[i*w + j + 1] = srcV[i / 2 * w / 2 + j / 2];
    				desV[(i + 1)*w + j] = srcV[i / 2 * w / 2 + j / 2];
    				desV[(i + 1)*w + j + 1] = srcV[i / 2 * w / 2 + j / 2];
    			}
    		}
    	}

--------------------

### 2、YUV444转YUV420 ###

与YUV420与YUV444思路类似的，我们反过来计算，将YUV444下采样为YUV420即可，

下面是C++实现YUV444转YUV420的代码：

void YUV444TOYUV420(unsigned char *inbuf, unsigned char *outbuf, int w, int h) {
    		unsigned char *srcY = NULL, *srcU = NULL, *srcV = NULL;
    		unsigned char *desY = NULL, *desU = NULL, *desV = NULL;
    		srcY = inbuf;//Y
    		srcU = srcY + w * h;//U
    		srcV = srcU + w * h;//V
    
    		desY = outbuf;
    		desU = desY + w * h;
    		desV = desU + w * h / 4;
    
    		int half_width = w / 2;
    		int half_height = h / 2;
    		memcpy(desY, srcY, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    		 //UV
    		for (int i = 0; i < half_height; i++) {
    			for (int j = 0; j < half_width; j++) {
    				*desU = *srcU;
    				*desV = *srcV;
    				desU++;
    				desV++;
    				srcU += 2;
    				srcV += 2;
    			}
    			srcU = srcU + w;
    			srcV = srcV + w;
    		}
    	}

--------------------

## 四、显示和播放YUV文件 ##

### 1、显示YUV图像 ###

YUV数据需要转到RGB才能显示正常，显示部分需要OpenCV的支持，OpenCV的配置，就不说啦，自己搞搞吧！！！这里提供有一个鄙人已经写好的*cv\_imageshow*()函数，可以实现将输入的YUV数据流转为BGR格式，再用OpenCV的imshow()直接进行显示。注意，这里提供*cv\_imageshow*()只能显示一帧数据，即你输入的inbuf数据流必须是一帧的YUV数据。

/*********************************************************
    	@brief         : 显示YUV图片，这里会将YUV转到RGB上进行显示
    	@param winname : 窗口显示的名称
    	@param inbuf   : YUV数据流，直接将read_yuvImage返回的YUV数据流传入即可显示
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : void
    	********************************************************/
    	void cv_imageshow(string winname, unsigned char* inframe, int w, int h, ColorSpace colorType) {
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			cv::Mat yuvMat = cv::Mat::zeros(h, w, CV_8UC3);
    			std::vector<cv::Mat> yuvChannels;
    			cv::split(yuvMat, yuvChannels);
    			yuvChannels.at(0).data = (unsigned char*)inframe;//Y
    			yuvChannels.at(1).data = (unsigned char*)inframe + w * h;//U
    			yuvChannels.at(2).data = (unsigned char*)inframe + w * h * 2;//V
    			cv::merge(yuvChannels, yuvMat);
    			cv::Mat bgrMat;
    			cv::cvtColor(yuvMat, bgrMat, CV_YUV2BGR);
    			cv::imshow(winname, bgrMat);
    			cv::waitKey(30);
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			int bufLen = w*h * 3 / 2;
    			cv::Mat yuvImg = cv::Mat::zeros(h * 3 / 2, w, CV_8UC1);
    			memcpy(yuvImg.data, inframe, bufLen * sizeof(unsigned char));
    			//cv::imshow(winname, yuvImg);
    			//cv::waitKey(30);
    			cv::Mat bgrImg= cv::Mat::zeros(h , w, CV_8UC3);
    			cv::cvtColor(yuvImg, bgrImg, CV_YUV2BGR_I420);
    			cv::imshow(winname, bgrImg);
    			cv::waitKey(30);
    		}
    	}

--------------------

### 2、播放YUV数据  ###

上面提供的*cv\_imageshow*()为了显示图片，所以只能显示一帧数据，即你输入的inbuf数据流必须是一帧的YUV数据。但很多YUV文件实质上是多帧的视频文件，要实现YUV文件的播放功能也很简单：循环读取YUV数据流，使用OpenCV的imshow()一帧一帧的显示，就实现了播放YUV的功能了：

下面是C++实现的cvPlayYUV444和cvPlayYUV420的函数，可以实现播放YUV444和YUV420的文件：

/*********************************************************
    	@brief         : 播放YUV420/YUV444文件
    	@param fileYUV : YUV文件
    	@param w       : 宽width
    	@param h       : 高height
    	@return        : void
    	********************************************************/
    	void cvPlayYUV444(string fileYUV, int w, int h) {
    		FILE* pFileIn = fopen(fileYUV.c_str(), "rb+");
    		int bufLen = w * h * 3;
    		unsigned char* pYuvBuf = new unsigned char[bufLen];
    		cv::Mat yuvMat = cv::Mat::zeros(h, w, CV_8UC3);
    		std::vector<cv::Mat> yuvChannels;
    		cv::split(yuvMat, yuvChannels);
    		while (fread(pYuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn))
    		{
    			//cv::Mat Y(i, w, CV_8UC1, (unsigned char*)pSrc);
    			//cv::Mat U(i, w, CV_8UC1, (unsigned char*)pSrc + w * i);
    			//cv::Mat V(i, w, CV_8UC1, (unsigned char*)pSrc + w * i * 2);
    			yuvChannels.at(0).data = (unsigned char*)pYuvBuf;//Y
    			yuvChannels.at(1).data = (unsigned char*)pYuvBuf + w * h;//U
    			yuvChannels.at(2).data = (unsigned char*)pYuvBuf + w * h * 2;//V
    			cv::merge(yuvChannels, yuvMat);
    			cv::Mat bgrMat;
    			cv::cvtColor(yuvMat, bgrMat, CV_YUV2BGR);
    			cv::imshow(" cvPlayYUV444", bgrMat);
    			cv::waitKey(30);
    		}
    		delete[] pYuvBuf;
    		fclose(pFileIn);
    	}
    
    
    	void cvPlayYUV420(string fileYUV, int w, int h)
    	{
    		FILE* pFileIn = fopen(fileYUV.c_str(), "rb+");
    		int bufLen = w*h * 3 / 2;
    		unsigned char* pYuvBuf = new unsigned char[bufLen];
    		while (fread(pYuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn))
    		{
    			cv::Mat yuvImg, rgbImg;
    			yuvImg.create(h * 3 / 2, w, CV_8UC1);
    			memcpy(yuvImg.data, pYuvBuf, bufLen * sizeof(unsigned char));
    			cv::Mat gray = yuvImg(cv::Rect(0, 0, w, h));
    			cv::cvtColor(yuvImg, rgbImg, CV_YUV2BGR_I420);
    			//
    			cv::imshow(" cvPlayYUV420", rgbImg);
    			cv::waitKey(30);
    		}
    		delete[] pYuvBuf;
    		fclose(pFileIn);
    	}

--------------------

## 五、完整的代码 ##

整理一下，这里提供了YUV.h和YUV.cpp源文件和测试main程序，*注意定义了namespace名称空间为cs*：

YUV444和YUV420的测试文件，可以这里[下载][Link 2]：[https://download.csdn.net/download/guyuealian/10697442][Link 2]

--------------------

YUV.h头文件：

#ifndef YUV_H
    #define YUV_H
    #include<opencv2/opencv.hpp>
    #include <string>
    using namespace std;
    namespace cs {
    	enum ColorSpace {
    		CS_YUV444,
    		CS_YUV420
    	};
    	enum ConvertColorSpace {
    		CS_YUV444TOYUV420,
    		CS_YUV420TOYUV444
    	};
    	/*********************************************************	
    	@brief         : 读取yuv图像文件,若输入的是多帧的图像文件,如yuv视频文件,则返回最后一帧的数据
    	@param fileYUV : YUV文件
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : unsigned char* 返回YUV数据
    	********************************************************/
    	unsigned char* read_yuvImage(string fileYUV, int w, int h, ColorSpace colorType);
    
    	/*********************************************************
    	@brief         : 播放YUV420/YUV444文件
    	@param fileYUV : YUV文件
    	@param w       : 宽width
    	@param h       : 高height
    	@return        : void
    	********************************************************/
    	void cvPlayYUV420(string fileYUV, int w, int h);
    	void cvPlayYUV444(string fileYUV, int w, int h);
    
    	/*********************************************************
    	@brief         : 显示YUV图片，这里会将YUV转到RGB上进行显示
    	@param winname : 窗口显示的名称
    	@param inbuf   : YUV数据流，直接将read_yuvImage返回的YUV数据流传入即可显示
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : void
    	********************************************************/
    	void cv_imageshow(string winname, unsigned char* inbuf, int w, int h, ColorSpace colorType);
    
    	/*********************************************************
    	@brief         : 保存YUV数据流
    	@param fileYUV : 输出YUV文件的路径
    	@param inbuf   : 需要保存的YUV数据流
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : void
    	********************************************************/
    	void write_yuvImage(string fileYUV, unsigned char* inbuf, int w, int h, ColorSpace colorType);
    
    	/*********************************************************
    	@brief         : 实现YUV420与YUV444数据之间的转换，实质上会分别调用YUV420TOYUV444和YUV444TOYUV420函数
    	@param inbuf   : 输入YUV数据流
    	@param w       : 宽width
    	@param h       : 高height
    	@param ConvertColorSpace: 转换颜色空间类型：
    	                         CS_YUV444TOYUV420：实现YUV444转YUV420
    							 CS_YUV420TOYUV444：实现YUV420转YUV444
    	@return        : unsigned char* 返回转换后的YUV数据
    	********************************************************/
    	unsigned char* convertYUV(unsigned char* inbuf, int w, int h, ConvertColorSpace type);
    	void YUV420TOYUV444(unsigned char *inbuf, unsigned char *outbuff, int w, int h);
    	void YUV444TOYUV420(unsigned char *inbuf, unsigned char *outbuff, int w, int h);
    
    	/*********************************************************
    	@brief         : 将YUV数据流转为OpenCV的Mat类型，方便使用OpenCV显示
    	@param inbuf   : 输入YUV数据流
    	@param w       : 宽width
    	@param h       : 高height
    	@param colorType: 颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : Mat类型图像数据
    	********************************************************/
    	cv::Mat YUVBufTOYUVMat(unsigned char* inbuf, int w, int h, ColorSpace colorType);
    
    	/*********************************************************
    	@brief         : 将OpenCV的Mat类型图像转YUV数据流
    	@param inbuf   : OpenCV的Mat类型图像
    	@param colorType: Mat类型图像颜色空间类型：CS_YUV444，CS_YUV420
    	@return        : unsigned char* 返回转换后的YUV数据流
    	********************************************************/
    	unsigned char* YUVMatTOYUVBUF(cv::Mat yuvMat, ColorSpace colorType);
    }
    #endif

--------------------

YUV.cpp实现文件：

#include "YUV.h"
    #include <opencv2/opencv.hpp>
    
    namespace cs {
    	//void read_yuvImage(string fileYUV, unsigned char* outYUV, int w, int i, ColorSpace colorType)
    	/*读取yuv图像文件，注意：若输入的是多帧的图像文件,如yuv视频文件,则返回最后一帧的数据*/
    	unsigned char* read_yuvImage(string fileYUV, int w, int h, ColorSpace colorType) {
    		FILE * pFileIn;      //输入CS_YUV444文件
    		if (NULL == (pFileIn = fopen(fileYUV.c_str(), "rb"))) {
    			printf("File input is can't open!\n");
    			fclose(pFileIn);
    			return nullptr;
    		}
    		int bufLen = 0;
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			bufLen = w * h * 3;
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			bufLen = w*h * 3 / 2;
    		}
    		unsigned char* yuvBuf = new unsigned char[bufLen];
    		//fread(yuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn);//返回第一帧
    		while (fread(yuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn))//返回最后一帧
    		{
    		}
    		fclose(pFileIn);
    		return yuvBuf;
    	}
    	void cvPlayYUV444(string fileYUV, int w, int h) {
    		FILE* pFileIn = fopen(fileYUV.c_str(), "rb+");
    		int bufLen = w * h * 3;
    		unsigned char* pYuvBuf = new unsigned char[bufLen];
    		cv::Mat yuvMat = cv::Mat::zeros(h, w, CV_8UC3);
    		std::vector<cv::Mat> yuvChannels;
    		cv::split(yuvMat, yuvChannels);
    		while (fread(pYuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn))
    		{
    			//cv::Mat Y(i, w, CV_8UC1, (unsigned char*)pSrc);
    			//cv::Mat U(i, w, CV_8UC1, (unsigned char*)pSrc + w * i);
    			//cv::Mat V(i, w, CV_8UC1, (unsigned char*)pSrc + w * i * 2);
    			yuvChannels.at(0).data = (unsigned char*)pYuvBuf;//Y
    			yuvChannels.at(1).data = (unsigned char*)pYuvBuf + w * h;//U
    			yuvChannels.at(2).data = (unsigned char*)pYuvBuf + w * h * 2;//V
    			cv::merge(yuvChannels, yuvMat);
    			cv::Mat bgrMat;
    			cv::cvtColor(yuvMat, bgrMat, CV_YUV2BGR);
    			cv::imshow(" cvPlayYUV444", bgrMat);
    			cv::waitKey(30);
    		}
    		delete[] pYuvBuf;
    		fclose(pFileIn);
    	}
    
    
    	void cvPlayYUV420(string fileYUV, int w, int h)
    	{
    		FILE* pFileIn = fopen(fileYUV.c_str(), "rb+");
    		int bufLen = w*h * 3 / 2;
    		unsigned char* pYuvBuf = new unsigned char[bufLen];
    		while (fread(pYuvBuf, bufLen * sizeof(unsigned char), 1, pFileIn))
    		{
    			cv::Mat yuvImg, rgbImg;
    			yuvImg.create(h * 3 / 2, w, CV_8UC1);
    			memcpy(yuvImg.data, pYuvBuf, bufLen * sizeof(unsigned char));
    			cv::Mat gray = yuvImg(cv::Rect(0, 0, w, h));
    			cv::cvtColor(yuvImg, rgbImg, CV_YUV2BGR_I420);
    			//
    			cv::imshow(" cvPlayYUV420", rgbImg);
    			cv::waitKey(30);
    		}
    		delete[] pYuvBuf;
    		fclose(pFileIn);
    	}
    
    	void write_yuvImage(string fileYUV, unsigned char* inframe, int w, int h, ColorSpace colorType) {
    		FILE * pFileOut;     //输出YUV文件
    		if (NULL == (pFileOut = fopen(fileYUV.c_str(), "wb"))) {
    			printf("File output is can't open!\n");
    			fclose(pFileOut);
    			return;
    		}
    		int bufLen = 0;
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			bufLen = w * h * 3;
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			bufLen = w*h * 3 / 2;
    		}
    		fwrite(inframe, bufLen * sizeof(unsigned char), 1, pFileOut);
    		fclose(pFileOut);
    	}
    
    	void cv_imageshow(string winname, unsigned char* inframe, int w, int h, ColorSpace colorType) {
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			cv::Mat yuvMat = cv::Mat::zeros(h, w, CV_8UC3);
    			std::vector<cv::Mat> yuvChannels;
    			cv::split(yuvMat, yuvChannels);
    			yuvChannels.at(0).data = (unsigned char*)inframe;//Y
    			yuvChannels.at(1).data = (unsigned char*)inframe + w * h;//U
    			yuvChannels.at(2).data = (unsigned char*)inframe + w * h * 2;//V
    			cv::merge(yuvChannels, yuvMat);
    			cv::Mat bgrMat;
    			cv::cvtColor(yuvMat, bgrMat, CV_YUV2BGR);
    			cv::imshow(winname, bgrMat);
    			cv::waitKey(30);
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			int bufLen = w*h * 3 / 2;
    			cv::Mat yuvImg = cv::Mat::zeros(h * 3 / 2, w, CV_8UC1);
    			memcpy(yuvImg.data, inframe, bufLen * sizeof(unsigned char));
    			//cv::imshow(winname, yuvImg);
    			//cv::waitKey(30);
    			cv::Mat bgrImg= cv::Mat::zeros(h , w, CV_8UC3);
    			cv::cvtColor(yuvImg, bgrImg, CV_YUV2BGR_I420);
    			cv::imshow(winname, bgrImg);
    			cv::waitKey(30);
    		}
    	}
    
    	void YUV420TOYUV444(unsigned char *inbuf, unsigned char *outbuf, int w, int h) {
    		unsigned char *srcY = NULL, *srcU = NULL, *srcV = NULL;
    		unsigned char *desY = NULL, *desU = NULL, *desV = NULL;
    		srcY = inbuf;//Y
    		srcU = srcY + w * h;//U
    		srcV = srcU + w * h / 4;;//V
    
    		desY = outbuf;
    		desU = desY + w * h;
    		desV = desU + w * h;
    		memcpy(desY, srcY, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    	   //UV分量转换
    		int i, j;
    		for (i = 0; i < h; i += 2) {//行
    			for (j = 0; j < w; j += 2) {//列
    										//U
    				desU[i*w + j] = srcU[i / 2 * w / 2 + j / 2];
    				desU[i*w + j + 1] = srcU[i / 2 * w / 2 + j / 2];
    				desU[(i + 1)*w + j] = srcU[i / 2 * w / 2 + j / 2];
    				desU[(i + 1)*w + j + 1] = srcU[i / 2 * w / 2 + j / 2];
    				//V
    				desV[i*w + j] = srcV[i / 2 * w / 2 + j / 2];
    				desV[i*w + j + 1] = srcV[i / 2 * w / 2 + j / 2];
    				desV[(i + 1)*w + j] = srcV[i / 2 * w / 2 + j / 2];
    				desV[(i + 1)*w + j + 1] = srcV[i / 2 * w / 2 + j / 2];
    			}
    		}
    	}
    	void YUV444TOYUV420(unsigned char *inbuf, unsigned char *outbuf, int w, int h) {
    		unsigned char *srcY = NULL, *srcU = NULL, *srcV = NULL;
    		unsigned char *desY = NULL, *desU = NULL, *desV = NULL;
    		srcY = inbuf;//Y
    		srcU = srcY + w * h;//U
    		srcV = srcU + w * h;//V
    
    		desY = outbuf;
    		desU = desY + w * h;
    		desV = desU + w * h / 4;
    
    		int half_width = w / 2;
    		int half_height = h / 2;
    		memcpy(desY, srcY, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    		 //UV
    		for (int i = 0; i < half_height; i++) {
    			for (int j = 0; j < half_width; j++) {
    				*desU = *srcU;
    				*desV = *srcV;
    				desU++;
    				desV++;
    				srcU += 2;
    				srcV += 2;
    			}
    			srcU = srcU + w;
    			srcV = srcV + w;
    		}
    	}
    
    	unsigned char* convertYUV(unsigned char* inbuf, int w, int h, ConvertColorSpace type) {
    		int bufLen = 0;
    		if (type == CS_YUV420TOYUV444) {//定义保存CS_YUV444的数组
    			bufLen = w * h * 3;
    			unsigned char* pDst = new unsigned char[bufLen];//定义保存YUV420的数组
    			YUV420TOYUV444(inbuf, pDst, w, h);
    			return pDst;
    		}
    		else if (type == CS_YUV444TOYUV420) {
    			bufLen = w*h * 3 / 2;
    			unsigned char* pDst = new unsigned char[bufLen];//定义保存YUV420的数组
    			YUV444TOYUV420(inbuf, pDst, w, h);
    			return pDst;
    		}
    	}
    	cv::Mat YUVBufTOYUVMat(unsigned char* inbuf,int w,int h, ColorSpace colorType) {
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			cv::Mat yuvMat = cv::Mat::zeros(h, w, CV_8UC3);
    			std::vector<cv::Mat> yuvChannels;
    			cv::split(yuvMat, yuvChannels);
    			yuvChannels.at(0).data = (unsigned char*)inbuf;//Y
    			yuvChannels.at(1).data = (unsigned char*)inbuf + w * h;//U
    			yuvChannels.at(2).data = (unsigned char*)inbuf + w * h * 2;//V
    			cv::merge(yuvChannels, yuvMat);
    			return yuvMat;
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			int bufLen = w*h * 3 / 2;
    			cv::Mat yuvMat= cv::Mat::zeros(h * 3 / 2, w, CV_8UC1);
    			memcpy(yuvMat.data, inbuf, bufLen * sizeof(unsigned char));
    			return yuvMat;
    		}
    
    	}
    
    	unsigned char* YUVMatTOYUVBUF(cv::Mat yuvMat, ColorSpace colorType) {
    		if (colorType == CS_YUV444) {//定义保存CS_YUV444的数组
    			int w = yuvMat.cols;
    			int h = yuvMat.rows;
    			int bufLen = w*h * 3;
    			unsigned char* outbuf = new unsigned char[bufLen];
    			std::vector<cv::Mat> yuvChannels;
    			cv::split(yuvMat, yuvChannels);
    			memcpy(outbuf, yuvChannels.at(0).data, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    			memcpy(outbuf + w * h, yuvChannels.at(1).data, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    			memcpy(outbuf + w * h * 2, yuvChannels.at(2).data, w * h * sizeof(unsigned char));//Y分量直接拷贝即可
    			return outbuf;
    		}
    		else if (colorType == CS_YUV420) {//定义保存YUV420的数组
    			int w = yuvMat.cols;
    			int h = yuvMat.rows;
    			int bufLen = yuvMat.total();//w*h ;
    			unsigned char* outbuf = new unsigned char[bufLen];
    			//outbuf = yuvMat.data;
    			memcpy(outbuf,yuvMat.data, bufLen * sizeof(unsigned char));
    			return outbuf;
    		}
    	}
    }

--------------------

YUV444与YUV420互转测试：

int main() {
    	string fileYUV = "D:\\imageEnhance\\YUVdata\\YUV444_1366_768.yuv";
    	//string fileYUV = "D:\\imageEnhance\\YUVdata\\yuv444_image_640_480.yuv";
    	//string fileYUV = "D:\\imageEnhance\\YUVdata\\sintel_640_360.yuv";
    	int w = 1366;
    	int h = 768;
    	char unsigned *yuv444_buf= cs::read_yuvImage(fileYUV, w, h, cs::CS_YUV444);//读取YUV数据
    	cs::cv_imageshow("CS_YUV444", yuv444_buf, w, h, cs::CS_YUV444);
    	char unsigned *yuv420_buf = cs::convertYUV(yuv444_buf, w, h, cs::CS_YUV444TOYUV420);//将YUV444转为YUV420
    	cs::cv_imageshow("CS_YUV420", yuv420_buf, w, h, cs::CS_YUV420);
    	cin.get();
    	return 0;
    }

YUV444与YUV420播放测试：

int main() {
    	//string fileYUV = "D:\\imageEnhance\\YUVdata\\YUV444_1366_768.yuv";
    	//string fileYUV = "D:\\imageEnhance\\YUVdata\\yuv444_image_640_480.yuv";
    	string fileYUV = "D:\\imageEnhance\\YUVdata\\sintel_640_360.yuv";
    	int w = 640;
    	int h = 360;
    	cs::cvPlayYUV420(fileYUV,w,h);
    	cin.get();
    	return 0;
    }

![70 1][]

--------------------

## **参考资料：** ##

> \[1\]《YUV420转YUV444》[https://blog.csdn.net/lin453701006/article/details/53053185][https_blog.csdn.net_lin453701006_article_details_53053185],这个博客的思路不错，就是代码太烂了。
> 
> \[2\]《YUV444与YUV422下采样》[https://blog.csdn.net/qq\_36113899/article/details/68958344][https_blog.csdn.net_qq_36113899_article_details_68958344]

如果你觉得该帖子帮到你，还望贵人多多支持，鄙人会再接再厉，继续努力的~

![70 2][]

[Link 1]: https://blog.csdn.net/guyuealian/article/details/82454945
[Link 2]: https://download.csdn.net/download/guyuealian/10697442
[20161106110000210]: /images/20220514/964e3c97364e4af6b1417817d8974422.png
[70]: /images/20220514/d566562e3ff14ac99cefdd3f9705b46b.png
[Link 3]: https://baike.baidu.com/item/%E6%96%87%E4%BB%B6%E6%8C%87%E9%92%88/1953678
[20161107104721573]: /images/20220514/6cd0d5ec2716425c8d9cb4f870d8684c.png
[20161107104831294]: /images/20220514/7dcbb5b654a74aecb776d97fdded6a39.png
[70 1]: /images/20220514/078186f431b34d7a8de7bc3d44e91044.png
[https_blog.csdn.net_lin453701006_article_details_53053185]: https://blog.csdn.net/lin453701006/article/details/53053185
[https_blog.csdn.net_qq_36113899_article_details_68958344]: https://blog.csdn.net/qq_36113899/article/details/68958344
[70 2]: /images/20220514/fe6f810ad66b453786a90b9d9bdcc461.png