C++ Bayer图像格式，使用GDAL进行格式转换。

Bayer图像说明

1、Bayer图像格式介绍

bayer格式图片是伊士曼·柯达公司科学家Bryce Bayer发明的，Bryce Bayer所发明的拜耳阵列被广泛运用数字图像。

对于彩色图像，需要采集多种最基本的颜色，如rgb三种颜色，最简单的方法就是用滤镜的方法，红色的滤镜透过红色的波长，绿色的滤镜透过绿色的波长，蓝色的滤镜透过蓝色的波长。如果要采集rgb三个基本色，则需要三块滤镜，这样价格昂贵，且不好制造，因为三块滤镜都必须保证每一个像素点都对齐。当用bayer格式的时候，很好的解决了这个问题。bayer 格式图片在一块滤镜上设置的不同的颜色，通过分析人眼对颜色的感知发现，人眼对绿色比较敏感，所以一般bayer格式的图片绿色格式的像素是是r和g像素的和。

另外，Bayer格式是相机内部的原始图片, 一般后缀名为.raw。很多软件都可以查看, 比如PS。我们相机拍照下来存储在存储卡上的.jpeg或其它格式的图片, 都是从.raw格式转化过来的。如下图，为bayer色彩滤波阵列，由一半的G，1/4的R，1/4的B组成。

2、Bayer图像传感原理

图像传感器的结构如下所示，每一个感光像素之间都有金属隔离层，光纤通过显微镜头，在色彩滤波器过滤之后，投射到相应的漏洞式硅的感光元件上。

当Image Sensor往外逐行输出数据时，像素的序列为GRGRGR…/BGBGBG…（顺序RGB）。这样阵列的Sensor设计，使得RGB传感器减少到了全色传感器的1/3，如下所示。

3、bayer格式插值红蓝算法实现

每一个像素仅仅包括了光谱的一部分，必须通过插值来实现每个像素的RGB值。为了从Bayer格式得到每个像素的RGB格式，我们需要通过插值填补缺失的2个色彩。插值的方法有很多（包括领域、线性、3*3等），速度与质量权衡，最好的线性插值补偿算法。其中算法如下：

R和B通过线性领域插值，但这有四种不同的分布，如下图所示：

A B

C D
在（a）与（b）中，R和B分别取邻域的平均值。

在（c）与（d）中，取领域的4个B或R的均值作为中间像素的B值。

4、bayer格式插值绿算法实现

E F
由于人眼对绿光反应最敏感，对紫光和红光则反应较弱，因此为了达到更好的画质，需要对G特殊照顾。在上述（c）与（d）中，扩展开来就是上图的（e）与（f）中间像素G的取值，者也有一定的算法要求，不同的算法效果上会有差异。经过相关的研究，
（e）中间像素G值的算法如下：

（f）中间像素G值的算法如下：

CMOS摄像头这部分转换是在内部用ADC或者ISP完成的，生产商为了降低成本必然会使得图像失真。当然用外部处理器来实现转换，如果处理器的速度足够NB，能够胜任像素的操作，用上面的算法来进行转换，皆大欢喜。不过上述算法将直接成倍提高了算法的复杂度，速度上将会有所限制。因此为了速度的提成，可以直接通过来4领域G取均值来中间像素的G值，将会降低一倍的速率，而在性能上差之甚微，算法如下：

如果能够通过损失图像的额质量，来达到更快的速度，还可以取G1、G2的均值来实现，但是这样的做法会导致边沿以及跳变部分的失真。

将Bayer格式转换为tif格式

//全部.h文件
#include <iostream>
#include <vector>
#include <fstream>
#include <gdal_priv.h>
#include <gdalwarper.h>
#include <gdal.h>
#include <stdio.h>
#include <stdlib.h>
#include "j2k_mem_advance.h"
#include "format_defs.h"
#include "j2k_mem.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/io.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <memory>
#include <dirent.h>
#include <dlfcn.h>
#include <fcntl.h>
#include <time.h>
#include <thread>
#include <stdio.h>
#include <string.h>
#include "TinyXML.h"using namespace std;

//此头文件应该是必须的部分
#include <iostream>
#include <fstream>
#include <gdal_priv.h>
#include <gdalwarper.h>
#include <gdal.h>
#include <stdio.h>
#include <stdlib.h>using namespace std;//核心代码部分
//将.dat文件读取后进行gbbr转换，最后转码为TIF文件
bool Anal_pixel(string strFilePath, string strSavePath, long nWidth, long nHeight, int nType)
{// TODO:  在此添加控件通知处理程序代码GDALAllRegister();CPLSetConfigOption("GDAL_FILENAME_IS_UTF8", "NO");   //支持中文路径if (strFilePath == ""){return false;}const char* pszFormat = "GTIFF";GDALDriver* poDriver = GetGDALDriverManager()->GetDriverByName(pszFormat);if (!poDriver) {return false;}//long width = 7920;//long height = 6004;long long width = nWidth;long long height = nHeight;GDALDataType gdal_data_type = GDT_UInt16;unsigned short* pData = new unsigned short[width * height];fstream sf;sf.open(strFilePath, ios::in | ios::binary);//打开文件，供读sf.seekg(0, ios::beg);//byte *bTemp = new byte[2];unsigned char* bTemp = new unsigned char[2];for (int i = 0; i < height * width; i++){sf.read((char*)&bTemp[0], sizeof(unsigned char));sf.read((char*)&bTemp[1], sizeof(unsigned char));pData[i] = bTemp[0] * 256 + bTemp[1];//char pBuff[8];//sprintf(pBuff, "%04x", pData[i]);//int isdsd = 0;}sf.close();delete[] bTemp;//----------------------解析
#pragma region 解析PointInfo** cArryAllPoint; // 二维数组cArryAllPoint = (PointInfo**)malloc(height * sizeof(PointInfo*));//height 行for (int i = 0; i < height; i++) {cArryAllPoint[i] = (PointInfo*)malloc(width * sizeof(PointInfo));//width 列}//读取文件，将文件中的数值填充for (long long y = 0; y < height; y++){for (long long x = 0; x < width / 2; x++){cArryAllPoint[y][2 * x].Point_X = 2 * x;cArryAllPoint[y][2 * x].Point_Y = y;cArryAllPoint[y][2 * x + 1].Point_X = 2 * x + 1;cArryAllPoint[y][2 * x + 1].Point_Y = y;if (y % 2 == 0){cArryAllPoint[y][2 * x].Point_B = pData[y * width / 4 + x + height * width * 1 / 2];//BcArryAllPoint[y][2 * x + 1].Point_G = pData[y * width / 2 + x];//G}else{cArryAllPoint[y][2 * x].Point_G = pData[y * width / 2 + x];//GcArryAllPoint[y][2 * x + 1].Point_R = pData[(y - 1) * width / 4 + x + height * width * 3 / 4];//R}}}delete[] pData;//释放内存//计算RGB值unsigned short R1, R2, R3, R4, B1, B2, B3, B4, G1, G2, G3, G4;for (long long y = 0; y < height; y++)//初始化数据 {for (long long x = 0; x < width; x++){if (y % 2 == 0){if (x % 2 == 0){if (x == 0){if (y == 0){R1 = 0;R2 = 0;R3 = 0;R4 = cArryAllPoint[y + 1][x + 1].Point_R;G1 = 0;G2 = 0;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = cArryAllPoint[y + 1][x].Point_G;}else if (y == height - 1){R1 = 0;R2 = 0;R3 = cArryAllPoint[y - 1][x + 1].Point_R;R4 = 0;G1 = 0;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = 0;}else{R1 = 0;R2 = 0;R3 = cArryAllPoint[y - 1][x + 1].Point_R;R4 = cArryAllPoint[y + 1][x + 1].Point_R;G1 = 0;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = cArryAllPoint[y + 1][x].Point_G;}}else if (x == width - 1){if (y == 0){R1 = cArryAllPoint[y + 1][x - 1].Point_R;R2 = 0;R3 = 0;R4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = 0;G3 = 0;G4 = cArryAllPoint[y + 1][x].Point_G;}else if (y == height - 1){R1 = 0;R2 = cArryAllPoint[y - 1][x - 1].Point_R;R3 = 0;R4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = 0;G4 = 0;}else{R1 = cArryAllPoint[y + 1][x - 1].Point_R;R2 = cArryAllPoint[y - 1][x - 1].Point_R;R3 = 0;R4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = 0;G4 = cArryAllPoint[y + 1][x].Point_G;}}else{if (y == 0){R1 = cArryAllPoint[y + 1][x - 1].Point_R;R2 = 0;R3 = 0;R4 = cArryAllPoint[y + 1][x + 1].Point_R;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = 0;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = cArryAllPoint[y + 1][x].Point_G;}else if (y == height - 1){R1 = 0;R2 = cArryAllPoint[y - 1][x - 1].Point_R;R3 = cArryAllPoint[y - 1][x + 1].Point_R;R4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = 0;}else{R1 = cArryAllPoint[y + 1][x - 1].Point_R;R2 = cArryAllPoint[y - 1][x - 1].Point_R;R3 = cArryAllPoint[y - 1][x + 1].Point_R;R4 = cArryAllPoint[y + 1][x + 1].Point_R;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = cArryAllPoint[y + 1][x].Point_G;}}cArryAllPoint[y][x].Point_R = (R1 + R2 + R3 + R4) / 4;cArryAllPoint[y][x].Point_G = (G1 + G2 + G3 + G4) / 4;}else{//unsigned short R1, R2, B1, B2;//G//G1,R2,G4//B1,G ,B2//G2,R1,G3//R1 = cArryAllPoint.GetAt(y - 1)->GetAt(x).Point_R;//R2 = cArryAllPoint.GetAt(y + 1)->GetAt(x).Point_R;//B1 = cArryAllPoint.GetAt(y)->GetAt(x - 1).Point_B;//B2 = cArryAllPoint.GetAt(y)->GetAt(x + 1).Point_B;if (x == 0){if (y == 0){R1 = 0;R2 = cArryAllPoint[y + 1][x].Point_R;B1 = 0;B2 = cArryAllPoint[y][x + 1].Point_B;}else if (y == height - 1){R1 = cArryAllPoint[y - 1][x].Point_R;R2 = 0;B1 = 0;B2 = cArryAllPoint[y][x + 1].Point_B;}else{R1 = cArryAllPoint[y - 1][x].Point_R;R2 = cArryAllPoint[y + 1][x].Point_R;B1 = 0;B2 = cArryAllPoint[y][x + 1].Point_B;}}else if (x == width - 1){if (y == 0){R1 = 0;R2 = cArryAllPoint[y + 1][x].Point_R;B1 = cArryAllPoint[y][x - 1].Point_B;B2 = 0;}else if (y == height - 1){R1 = cArryAllPoint[y - 1][x].Point_R;R2 = 0;B1 = cArryAllPoint[y][x - 1].Point_B;B2 = 0;}else{R1 = cArryAllPoint[y - 1][x].Point_R;R2 = cArryAllPoint[y + 1][x].Point_R;B1 = cArryAllPoint[y][x - 1].Point_B;B2 = 0;}}else{if (y == 0){R1 = 0;R2 = cArryAllPoint[y + 1][x].Point_R;B1 = cArryAllPoint[y][x - 1].Point_B;B2 = cArryAllPoint[y][x + 1].Point_B;}else if (y == height - 1){R1 = cArryAllPoint[y - 1][x].Point_R;R2 = 0;B1 = cArryAllPoint[y][x - 1].Point_B;B2 = cArryAllPoint[y][x + 1].Point_B;}else{R1 = cArryAllPoint[y - 1][x].Point_R;R2 = cArryAllPoint[y + 1][x].Point_R;B1 = cArryAllPoint[y][x - 1].Point_B;B2 = cArryAllPoint[y][x + 1].Point_B;}}cArryAllPoint[y][x].Point_R = (R1 + R2) / 2;cArryAllPoint[y][x].Point_B = (B1 + B2) / 2;}}else{if (x % 2 == 0){//unsigned short R1, R2, B1, B2;//G//G1,B2,G4//R1,G ,R2//G2,B1,G3//R1 = cArryAllPoint.GetAt(y)->GetAt(x - 1).Point_R;//R2 = cArryAllPoint.GetAt(y)->GetAt(x + 1).Point_R;//B1 = cArryAllPoint.GetAt(y - 1)->GetAt(x).Point_B;//B2 = cArryAllPoint.GetAt(y + 1)->GetAt(x).Point_B;if (x == 0){if (y == 0){R1 = 0;R2 = cArryAllPoint[y][x + 1].Point_R;B1 = 0;B2 = cArryAllPoint[y + 1][x].Point_B;}else if (y == height - 1){R1 = 0;R2 = cArryAllPoint[y][x + 1].Point_R;B1 = cArryAllPoint[y - 1][x].Point_B;B2 = 0;}else{R1 = 0;R2 = cArryAllPoint[y][x + 1].Point_R;B1 = cArryAllPoint[y - 1][x].Point_B;B2 = cArryAllPoint[y + 1][x].Point_B;}}else if (x == width - 1){if (y == 0){R1 = cArryAllPoint[y][x - 1].Point_R;R2 = 0;B1 = 0;B2 = cArryAllPoint[y + 1][x].Point_B;}else if (y == height - 1){R1 = cArryAllPoint[y][x - 1].Point_R;R2 = 0;B1 = cArryAllPoint[y - 1][x].Point_B;B2 = 0;}else{R1 = cArryAllPoint[y][x - 1].Point_R;R2 = 0;B1 = cArryAllPoint[y - 1][x].Point_B;B2 = cArryAllPoint[y + 1][x].Point_B;}}else{if (y == 0){R1 = cArryAllPoint[y][x - 1].Point_R;R2 = cArryAllPoint[y][x + 1].Point_R;B1 = 0;B2 = cArryAllPoint[y + 1][x].Point_B;}else if (y == height - 1){R1 = cArryAllPoint[y][x - 1].Point_R;R2 = cArryAllPoint[y][x + 1].Point_R;B1 = cArryAllPoint[y - 1][x].Point_B;B2 = 0;}else{R1 = cArryAllPoint[y][x - 1].Point_R;R2 = cArryAllPoint[y][x + 1].Point_R;B1 = cArryAllPoint[y - 1][x].Point_B;B2 = cArryAllPoint[y + 1][x].Point_B;}}cArryAllPoint[y][x].Point_R = (R1 + R2) / 2;cArryAllPoint[y][x].Point_B = (B1 + B2) / 2;}else{//unsigned short B1, B2, B3, B4, G1, G2, G3, G4;//R//B1,G4,B4//G1,R ,G3//B2,G2,B3//B1 = cArryAllPoint.GetAt(y + 1)->GetAt(x - 1).Point_B;//B2 = cArryAllPoint.GetAt(y - 1)->GetAt(x - 1).Point_B;//B3 = cArryAllPoint.GetAt(y - 1)->GetAt(x + 1).Point_B;//B4 = cArryAllPoint.GetAt(y + 1)->GetAt(x + 1).Point_B;//G1 = cArryAllPoint.GetAt(y)->GetAt(x - 1).Point_G;//G2 = cArryAllPoint.GetAt(y - 1)->GetAt(x).Point_G;//G3 = cArryAllPoint.GetAt(y)->GetAt(x + 1).Point_G;//G4 = cArryAllPoint.GetAt(y + 1)->GetAt(x).Point_G;if (x == 0){//不存在 X=0}else if (x == width - 1){if (y == 0){//不存在 Y=0}else if (y == height - 1){B1 = 0;B2 = cArryAllPoint[y - 1][x - 1].Point_B;B3 = 0;B4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = 0;G4 = 0;}else{B1 = cArryAllPoint[y + 1][x - 1].Point_B;B2 = cArryAllPoint[y - 1][x - 1].Point_B;B3 = 0;B4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = 0;G4 = cArryAllPoint[y + 1][x].Point_G;}}else{if (y == 0){//不存在 Y=0}else if (y == height - 1){B1 = 0;B2 = cArryAllPoint[y - 1][x - 1].Point_B;B3 = cArryAllPoint[y - 1][x + 1].Point_B;B4 = 0;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = 0;}else{B1 = cArryAllPoint[y + 1][x - 1].Point_B;B2 = cArryAllPoint[y - 1][x - 1].Point_B;B3 = cArryAllPoint[y - 1][x + 1].Point_B;B4 = cArryAllPoint[y + 1][x + 1].Point_B;G1 = cArryAllPoint[y][x - 1].Point_G;G2 = cArryAllPoint[y - 1][x].Point_G;G3 = cArryAllPoint[y][x + 1].Point_G;G4 = cArryAllPoint[y + 1][x].Point_G;}}cArryAllPoint[y][x].Point_B = (B1 + B2 + B3 + B4) / 4;cArryAllPoint[y][x].Point_G = (G1 + G2 + G3 + G4) / 4;}}}}//整合到pDataRGB中//unsigned char * pDataRGB = new unsigned char[width * height * 3];unsigned short** newbuffs = new unsigned short* [3]; // 1, 2, 3 : r g b newbuffs[0] = new unsigned short[width * height];newbuffs[1] = new unsigned short[width * height];newbuffs[2] = new unsigned short[width * height];double dTemp;for (long long y = 0; y < height; y++)//初始化数据{for (long long x = 0; x < width; x++){dTemp = (double)cArryAllPoint[y][x].Point_R;newbuffs[0][y * width + x] = (unsigned short)dTemp;dTemp = (double)cArryAllPoint[y][x].Point_G;newbuffs[1][y * width + x] = (unsigned short)dTemp;dTemp = (double)cArryAllPoint[y][x].Point_B;newbuffs[2][y * width + x] = (unsigned short)dTemp;}}double minDN[3] = { 0 };//统计最小的DN值double maxDN[3] = { 0 };//统计最大的DN值//释放内存 cArryAllPointfor (int i = 0; i < height; i++){delete[] cArryAllPoint[i];}free(cArryAllPoint);//将原数据进行拉伸放大for (long long m = 0; m < height; m++){for (long long n = 0; n < width; n++){for (long long i = 0; i < 3; i++){if (newbuffs[i][m * width + n] < minDN[i])minDN[i] = newbuffs[i][m * width + n];if (newbuffs[i][m * width + n] > maxDN[i])maxDN[i] = newbuffs[i][m * width + n];}}}for (long long i = 0; i < 3; i++){for (long long m = 0; m < height*width; m++){newbuffs[i][m] = (newbuffs[i][m] - minDN[i]) * 1.0 / (maxDN[i] - minDN[i]) * 65535;}}#pragma endregionif (nType == 0)//拉伸后的图像{char** papszOptions = nullptr;papszOptions = CSLSetNameValue(papszOptions, "INTERLEAVE", "BAND");papszOptions = CSLSetNameValue(papszOptions, "BIGTIFF", "IF_NEEDED");const char* pszDstFilename = strSavePath.c_str();GDALDataset* poDstDS = poDriver->Create(pszDstFilename, width, height, 3, GDT_UInt16, papszOptions);if (!poDstDS) {for (int i = 0; i < 3; i++){delete[] newbuffs[i];}free(newbuffs);return false;}int bandMap[3] = { 1, 2, 3 };for (int i = 0; i < 3; i++){poDstDS->GetRasterBand(i + 1)->RasterIO(GF_Write, 0, 0, width, height, newbuffs[i], width, height, GDT_UInt16, 0, 0, 0);delete[] newbuffs[i];}free(newbuffs);GDALClose((GDALDatasetH)poDstDS);}else{//针对原图16位的值进行高8位、低8位、中8位的转换。unsigned char** newbuffs1 = new unsigned char* [3]; // 1, 2, 3 : r g b newbuffs1[0] = new unsigned char[width * height];newbuffs1[1] = new unsigned char[width * height];newbuffs1[2] = new unsigned char[width * height];for (long long i = 0; i < 3; i++){for (long long m = 0; m < height; m++){for (long long n = 0; n < width; n++){char pBuff[4], pBuff2[8];if (nType == 1)//高8{newbuffs1[i][m * width + n] = newbuffs[i][m * width + n] / 4;//------G8}else if (nType == 2)//中8{newbuffs1[i][m * width + n] = newbuffs[i][m * width + n] / 2;//-------M8}else if (nType == 3)//低8{newbuffs1[i][m * width + n] = newbuffs[i][m * width + n];//------D8}}}}char** papszOptions = nullptr;papszOptions = CSLSetNameValue(papszOptions, "INTERLEAVE", "BAND");papszOptions = CSLSetNameValue(papszOptions, "BIGTIFF", "IF_NEEDED");const char* pszDstFilename = strSavePath.c_str();GDALDataset* poDstDS = poDriver->Create(pszDstFilename, width, height, 3, GDT_Byte, papszOptions);if (!poDstDS) {for (int i = 0; i < 3; i++){delete[] newbuffs[i];delete[] newbuffs1[i];}return false;}int bandMap[3] = { 1, 2, 3 };for (int i = 0; i < 3; i++){poDstDS->GetRasterBand(i + 1)->RasterIO(GF_Write, 0, 0, width, height, newbuffs1[i], width, height, GDT_Byte, 0, 0, 0);delete[] newbuffs[i];delete[] newbuffs1[i];}GDALClose((GDALDatasetH)poDstDS);}return true;
}

第一次书写博客会有些许乱，有需求的可以私我或者留言询问具体问题。

参考文件：

感谢作者：
淇淇宝贝 https://www.cnblogs.com/qiqibaby/p/5267566.html