基于C++读取图片的EXIF信息。

一、引子

可交换图像文件格式（英语：Exchangeable image file format，官方简称Exif），是专门为数码相机的照片设定的，可以记录数码照片的属性信息和拍摄数据。

Exif可以附加于JPEG、TIFF、RIFF等文件之中，为其增加有关数码相机拍摄信息的内容和索引图或图像处理软件的版本信息。

二、代码实现

#include <stdio.h>
#include "exif.h"
#include <string>

int main(int argc, char *argv[]) {

	// 在这里修改图片路径
	const char *photoPath = "图片路径";
	// 用 fopen_s 代替 fopen
	FILE *fp;
	if (fopen_s(&fp, photoPath, "rb") != 0) {
		printf("Can't open file.\n");
		return -1;
	}
	// 其余代码保持不变
	fseek(fp, 0, SEEK_END);
	unsigned long fsize = ftell(fp);
	rewind(fp);
	unsigned char *buf = new unsigned char[fsize];
	if (fread(buf, 1, fsize, fp) != fsize) {
		printf("Can't read file.\n");
		delete[] buf;
		return -2;
	}
	fclose(fp);

	// Parse EXIF
	easyexif::EXIFInfo result;
	int code = result.parseFrom(buf, fsize);
	delete[] buf;
	if (code) {
		printf("Error parsing EXIF: code %d\n", code);
		return -3;
	}

	// Dump EXIF information
	printf("Camera make          : %s\n", result.Make.c_str());
	printf("Camera model         : %s\n", result.Model.c_str());
	printf("Software             : %s\n", result.Software.c_str());
	printf("Bits per sample      : %d\n", result.BitsPerSample);
	printf("Image width          : %d\n", result.ImageWidth);
	printf("Image height         : %d\n", result.ImageHeight);
	printf("Image description    : %s\n", result.ImageDescription.c_str());
	printf("Image orientation    : %d\n", result.Orientation);
	printf("Image copyright      : %s\n", result.Copyright.c_str());
	printf("Image date/time      : %s\n", result.DateTime.c_str());
	printf("Original date/time   : %s\n", result.DateTimeOriginal.c_str());
	printf("Digitize date/time   : %s\n", result.DateTimeDigitized.c_str());
	printf("Subsecond time       : %s\n", result.SubSecTimeOriginal.c_str());
	printf("Exposure time        : 1/%d s\n", (unsigned)(1.0 / result.ExposureTime));
	printf("F-stop               : f/%.1f\n", result.FNumber);
	printf("Exposure program     : %d\n", result.ExposureProgram);
	printf("ISO speed            : %d\n", result.ISOSpeedRatings);
	printf("Subject distance     : %f m\n", result.SubjectDistance);
	printf("Exposure bias        : %f EV\n", result.ExposureBiasValue);
	printf("Flash used?          : %d\n", result.Flash);
	printf("Flash returned light : %d\n", result.FlashReturnedLight);
	printf("Flash mode           : %d\n", result.FlashMode);
	printf("Metering mode        : %d\n", result.MeteringMode);
	printf("Lens focal length    : %f mm\n", result.FocalLength);
	printf("35mm focal length    : %u mm\n", result.FocalLengthIn35mm);
	printf("GPS Latitude         : %f deg (%f deg, %f min, %f sec %c)\n", result.GeoLocation.Latitude, result.GeoLocation.LatComponents.degrees,
		result.GeoLocation.LatComponents.minutes,
		result.GeoLocation.LatComponents.seconds,
		result.GeoLocation.LatComponents.direction);
	printf("GPS Longitude        : %f deg (%f deg, %f min, %f sec %c)\n", result.GeoLocation.Longitude, result.GeoLocation.LonComponents.degrees,
		result.GeoLocation.LonComponents.minutes,
		result.GeoLocation.LonComponents.seconds,
		result.GeoLocation.LonComponents.direction);
	printf("GPS Altitude         : %f m\n", result.GeoLocation.Altitude);
	printf("GPS Precision (DOP)  : %f\n", result.GeoLocation.DOP);
	printf("Lens min focal length: %f mm\n", result.LensInfo.FocalLengthMin);
	printf("Lens max focal length: %f mm\n", result.LensInfo.FocalLengthMax);
	printf("Lens f-stop min      : f/%.1f\n", result.LensInfo.FStopMin);
	printf("Lens f-stop max      : f/%.1f\n", result.LensInfo.FStopMax);
	printf("Lens make            : %s\n", result.LensInfo.Make.c_str());
	printf("Lens model           : %s\n", result.LensInfo.Model.c_str());
	printf("Focal plane XRes     : %f\n", result.LensInfo.FocalPlaneXResolution);
	printf("Focal plane YRes     : %f\n", result.LensInfo.FocalPlaneYResolution);
	printf("Roll                 : %f degrees\n", result.Roll);
printf("Pitch                : %f degrees\n", result.Pitch);
printf("Yaw                  : %f degrees\n", result.Yaw);

	return 0;
}