一、图像详细信息
1.在windows下,点击图像,右键属性,详细信息里面,就可以查看该图像的具体信息,如水平分辨率,分辨率,宽度,高度等,如下图:
2.这此信息对于做图像处理是很有用处的,我一直在用OpenCV做相关的图像处理,但查了文档,好像OpenCV没有获取这些信息相关的函数,OpenCV可以获取图像的位深度,但对位深度是40的图像,OpenCV获取的并不准确。那么只能借助于别的工具库,比如GDI+ 或者是EXIV2,我这里用的是EXIV2。
3.我的编程环境是VS2015,WIN10 64,可以从我上传的资源下载编译好的EXIV2库。
二、EXIV2
1.下载地址https://www.exiv2.org/,进去后下载已编译好的msvc64库,或者下载源码自己Cmake也可以。
2.把lib和include加到工程的相关目录下,把bin加到系统环境变量里面,然后在附加依赖项里面加上lib的文件名。
三、测试源码
#include <exiv2/exiv2.hpp>
#include <iostream>
#include <string>
std::string FindExifKey(Exiv2::ExifData &ed, std::string key)
{
Exiv2::ExifKey tmp = Exiv2::ExifKey(key);
Exiv2::ExifData::iterator pos = ed.findKey(tmp);
if (pos == ed.end())
{
return "Unknow";
}
return pos->value().toString();
}
int main(void)
{
//输入的图像路径
std::string image_path = "5.JPG";
static std::unique_ptr<Exiv2::Image> image = Exiv2::ImageFactory::open(image_path);//尽量别这么写
if (image.get() == 0)
{
std::cout << "Read Exif Error." << std::endl;
return -1;
}
//读取照片的exif信息
image->readMetadata();
Exiv2::ExifData ed = image->exifData();//得到exif信息
if (ed.empty())
{
std::cout << "Not Find ExifInfo" << std::endl;
return -1;
}
std::cout << "版权 :" << FindExifKey(ed, "Exif.Image.Copyright") << std::endl;
std::cout << "创作人 :" << FindExifKey(ed, "Exif.Image.Artist") << std::endl;
std::cout << "相机品牌 :" << FindExifKey(ed, "Exif.Image.Make") << std::endl;
std::cout << "相机型号 :" << FindExifKey(ed, "Exif.Image.Model") << std::endl;
std::cout << "镜头型号 :" << FindExifKey(ed, "Exif.Photo.LensModel") << std::endl;
std::cout << "镜头序列号 :" << FindExifKey(ed, "Exif.Photo.LensSerialNumber") << std::endl;
std::cout << "ISO :" << FindExifKey(ed, "Exif.Photo.ISOSpeedRatings") << std::endl;
std::cout << "光圈 :" << FindExifKey(ed, "Exif.Photo.FNumber") << std::endl;
std::cout << "焦距 :" << FindExifKey(ed, "Exif.Photo.FocalLength") << std::endl;
std::cout << "快门 :" << FindExifKey(ed, "Exif.Photo.ExposureTime") << std::endl;
std::cout << "拍摄时间 :" << FindExifKey(ed, "Exif.Image.DateTime") << std::endl;
std::cout << "闪光灯 :" << FindExifKey(ed, "Exif.CanonCs.FlashMode") << std::endl;
std::cout << "水平分辨率 :" << FindExifKey(ed, "Exif.Image.XResolution") << std::endl;
std::cout << "垂直分辨率 :" << FindExifKey(ed, "Exif.Image.YResolution") << std::endl;
std::cout << "照片尺寸 :" << FindExifKey(ed, "Exif.Photo.PixelYDimension") << " x " << FindExifKey(ed, "Exif.Photo.PixelXDimension") << std::endl;
return 0;
}
运行结果: