获取图片的metaData

获取简易的metaData较为容易,以下是测试图:

以下是本人提供的源码:

UIImage+MetaData.h

//
// UIImage+MetaData.h
// PictureInfo
//
// Created by YouXianMing on 14-8-27.
// Copyright (c) 2014年 YouXianMing. All rights reserved.
// #import <UIKit/UIKit.h> @interface UIImage (MetaData) - (NSDictionary *)JPEGmetaData;
- (NSDictionary *)PNGmetaData; @end

UIImage+MetaData.h

//
// UIImage+MetaData.m
// PictureInfo
//
// Created by YouXianMing on 14-8-27.
// Copyright (c) 2014年 YouXianMing. All rights reserved.
// #import "UIImage+MetaData.h"
#import <AssetsLibrary/AssetsLibrary.h>
#import <ImageIO/ImageIO.h> @implementation UIImage (MetaData) - (NSDictionary *)JPEGmetaData
{
if (self == nil)
{
return nil;
} // 转换成jpegData,信息要多一些
NSData *jpegData = UIImageJPEGRepresentation(self, 1.0);
CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)jpegData, NULL);
CFDictionaryRef imageMetaData = CGImageSourceCopyPropertiesAtIndex(source, , NULL);
CFRelease(source); NSDictionary *metaDataInfo = CFBridgingRelease(imageMetaData);
return metaDataInfo;
} - (NSDictionary *)PNGmetaData
{
if (self == nil)
{
return nil;
} NSData *pngData = UIImagePNGRepresentation(self);
CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)pngData , NULL);
CFDictionaryRef imageMetaData = CGImageSourceCopyPropertiesAtIndex(source, , NULL);
CFRelease(source); NSDictionary *metaDataInfo = CFBridgingRelease(imageMetaData);
return metaDataInfo;
} @end

使用情况:

//
// AppDelegate.m
// GetPictureInfo
//
// Copyright (c) 2014年 Y.X. All rights reserved.
// #import "AppDelegate.h"
#import "UIImage+MetaData.h" @implementation AppDelegate - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch. NSLog(@"%@", [[UIImage imageNamed:@"IMG_0151.JPG"] JPEGmetaData]); self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
} @end

以下是打印信息:

{
    ColorModel = RGB;
    Depth = 8;
    Orientation = 1;
    PixelHeight = 1936;
    PixelWidth = 2592;
    "{Exif}" =     {
        ColorSpace = 1;
        PixelXDimension = 2592;
        PixelYDimension = 1936;
    };
    "{JFIF}" =     {
        DensityUnit = 0;
        JFIFVersion =         (
            1,
            1
        );
        XDensity = 1;
        YDensity = 1;
    };
    "{TIFF}" =     {
        Orientation = 1;
    };
}
几个需要注意的地方:

1. 需要引入两个库

2. 一些需要注意的细节

你以为结束了么?没有呢,你还没取到图片的经纬度信息,对吧,一下给你提供资料自己去尝试:)

http://stackoverflow.com/questions/9766394/get-exif-data-from-uiimage-uiimagepickercontroller

How can we get Exif information from UIImage selected from UIImagePickerController?

I had done much R&D for this and got many replies but still failed to implement this.

I had gone through this this and this link

Please help me to solve this problem.

Thanks in advance..

asked Mar 19 '12 at 7:22
iOS developer
8,688124776
 

5 Answers

Interesting question! I came up with the following solution working
for images picked from your photo library (note my code is using ARC):

Import AssetsLibrary.framework and ImageIO.framework.

Then include the needed classes inside your .h-file:

#import <AssetsLibrary/ALAsset.h>
#import <AssetsLibrary/ALAssetRepresentation.h>
#import <ImageIO/CGImageSource.h>
#import <ImageIO/CGImageProperties.h>

And put this inside your imagePickerController:didFinishPickingMediaWithInfo: delegate method:

ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
[library assetForURL:[info objectForKey:UIImagePickerControllerReferenceURL]
resultBlock:^(ALAsset *asset) { ALAssetRepresentation *image_representation = [asset defaultRepresentation]; // create a buffer to hold image data
uint8_t *buffer = (Byte*)malloc(image_representation.size);
NSUInteger length = [image_representation getBytes:buffer fromOffset: 0.0 length:image_representation.size error:nil]; if (length != 0) { // buffer -> NSData object; free buffer afterwards
NSData *adata = [[NSData alloc] initWithBytesNoCopy:buffer length:image_representation.size freeWhenDone:YES]; // identify image type (jpeg, png, RAW file, ...) using UTI hint
NSDictionary* sourceOptionsDict = [NSDictionary dictionaryWithObjectsAndKeys:(id)[image_representation UTI] ,kCGImageSourceTypeIdentifierHint,nil]; // create CGImageSource with NSData
CGImageSourceRef sourceRef = CGImageSourceCreateWithData((__bridge CFDataRef) adata, (__bridge CFDictionaryRef) sourceOptionsDict); // get imagePropertiesDictionary
CFDictionaryRef imagePropertiesDictionary;
imagePropertiesDictionary = CGImageSourceCopyPropertiesAtIndex(sourceRef,0, NULL); // get exif data
CFDictionaryRef exif = (CFDictionaryRef)CFDictionaryGetValue(imagePropertiesDictionary, kCGImagePropertyExifDictionary);
NSDictionary *exif_dict = (__bridge NSDictionary*)exif;
NSLog(@"exif_dict: %@",exif_dict); // save image WITH meta data
NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSURL *fileURL = nil;
CGImageRef imageRef = CGImageSourceCreateImageAtIndex(sourceRef, 0, imagePropertiesDictionary); if (![[sourceOptionsDict objectForKey:@"kCGImageSourceTypeIdentifierHint"] isEqualToString:@"public.tiff"])
{
fileURL = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/%@.%@",
documentsDirectory,
@"myimage",
[[[sourceOptionsDict objectForKey:@"kCGImageSourceTypeIdentifierHint"] componentsSeparatedByString:@"."] objectAtIndex:1]
]]; CGImageDestinationRef dr = CGImageDestinationCreateWithURL ((__bridge CFURLRef)fileURL,
(__bridge CFStringRef)[sourceOptionsDict objectForKey:@"kCGImageSourceTypeIdentifierHint"],
1,
NULL
);
CGImageDestinationAddImage(dr, imageRef, imagePropertiesDictionary);
CGImageDestinationFinalize(dr);
CFRelease(dr);
}
else
{
NSLog(@"no valid kCGImageSourceTypeIdentifierHint found …");
} // clean up
CFRelease(imageRef);
CFRelease(imagePropertiesDictionary);
CFRelease(sourceRef);
}
else {
NSLog(@"image_representation buffer length == 0");
}
}
failureBlock:^(NSError *error) {
NSLog(@"couldn't get asset: %@", error);
}
];

One thing I noticed is, that iOS will ask the user to allow location services – if he denies, you won't be abled to get the image data …

EDIT

Added code to save the image including its meta data. It's a quick approach, so maybe there is a better way, but it works!

answered Mar 19 '12 at 8:42

dom
6,80132550
 
    
Can you plz tell me how to save image after getting exif data?
– 
iOS developer
Mar 19 '12 at 9:40
    
+1 Cool answer..
– 
iOS developer
Mar 19 '12 at 9:44
    
@Marvin Check out my edit :P
– 
dom
Mar 19 '12 at 10:54
    
plz tell me what is "__bridge" in your code? :-)
– 
iOS developer
Mar 19 '12 at 11:05
    
@Marvin I'm using ARC. __bridge
is one of a hand full of keywords, which tell ARC about the objects
ownership so it can properly clean them up. The simplest case is a __bridge cast, for which ARC will not do any extra work (it assumes you handle the object's memory yourself).
– 
dom
Mar 21 '12 at 6:45

up vote
15
down vote

accepted

I had found solution and got answer from here

From here We can get GPS info as well..

Amazing and thanks all for helping me to solve this problem.

UPDATE

This is another function that I had created myself, also return Exif
data as well as GPS data and in this function we doesn't need any third
party library.. but you have to turn on location services for this. and
use current latitude and longitude for that. so have to use CoreLocation.framework

//FOR CAMERA IMAGE

-(NSMutableData *)getImageWithMetaData:(UIImage *)pImage
{
NSData* pngData = UIImagePNGRepresentation(pImage); CGImageSourceRef source = CGImageSourceCreateWithData((CFDataRef)pngData, NULL);
NSDictionary *metadata = (NSDictionary *) CGImageSourceCopyPropertiesAtIndex(source, 0, NULL); NSMutableDictionary *metadataAsMutable = [[metadata mutableCopy]autorelease];
[metadata release]; //For GPS Dictionary
NSMutableDictionary *GPSDictionary = [[[metadataAsMutable objectForKey:(NSString *)kCGImagePropertyGPSDictionary]mutableCopy]autorelease];
if(!GPSDictionary)
GPSDictionary = [NSMutableDictionary dictionary]; [GPSDictionary setValue:[NSNumber numberWithDouble:currentLatitude] forKey:(NSString*)kCGImagePropertyGPSLatitude];
[GPSDictionary setValue:[NSNumber numberWithDouble:currentLongitude] forKey:(NSString*)kCGImagePropertyGPSLongitude]; NSString* ref;
if (currentLatitude <0.0)
ref = @"S";
else
ref =@"N";
[GPSDictionary setValue:ref forKey:(NSString*)kCGImagePropertyGPSLatitudeRef]; if (currentLongitude <0.0)
ref = @"W";
else
ref =@"E";
[GPSDictionary setValue:ref forKey:(NSString*)kCGImagePropertyGPSLongitudeRef]; [GPSDictionary setValue:[NSNumber numberWithFloat:location.altitude] forKey:(NSString*)kCGImagePropertyGPSAltitude]; //For EXIF Dictionary
NSMutableDictionary *EXIFDictionary = [[[metadataAsMutable objectForKey:(NSString *)kCGImagePropertyExifDictionary]mutableCopy]autorelease];
if(!EXIFDictionary)
EXIFDictionary = [NSMutableDictionary dictionary]; [EXIFDictionary setObject:[NSDate date] forKey:(NSString*)kCGImagePropertyExifDateTimeOriginal];
[EXIFDictionary setObject:[NSDate date] forKey:(NSString*)kCGImagePropertyExifDateTimeDigitized]; //add our modified EXIF data back into the image’s metadata
[metadataAsMutable setObject:EXIFDictionary forKey:(NSString *)kCGImagePropertyExifDictionary];
[metadataAsMutable setObject:GPSDictionary forKey:(NSString *)kCGImagePropertyGPSDictionary]; CFStringRef UTI = CGImageSourceGetType(source); NSMutableData *dest_data = [NSMutableData data];
CGImageDestinationRef destination = CGImageDestinationCreateWithData((CFMutableDataRef)dest_data, UTI, 1, NULL); if(!destination)
dest_data = [[pngData mutableCopy] autorelease];
else
{
CGImageDestinationAddImageFromSource(destination, source, 0, (CFDictionaryRef) metadataAsMutable);
BOOL success = CGImageDestinationFinalize(destination);
if(!success)
dest_data = [[pngData mutableCopy] autorelease];
} if(destination)
CFRelease(destination); CFRelease(source); return dest_data;
} //FOR PHOTO LIBRARY IMAGE -(NSMutableData *)getImagedataPhotoLibrary:(NSDictionary *)pImgDictionary andImage:(UIImage *)pImage
{
NSData* data = UIImagePNGRepresentation(pImage); CGImageSourceRef source = CGImageSourceCreateWithData((CFDataRef)data, NULL);
NSMutableDictionary *metadataAsMutable = [[pImgDictionary mutableCopy]autorelease]; CFStringRef UTI = CGImageSourceGetType(source); NSMutableData *dest_data = [NSMutableData data]; //For Mutabledata
CGImageDestinationRef destination = CGImageDestinationCreateWithData((CFMutableDataRef)dest_data, UTI, 1, NULL); if(!destination)
dest_data = [[data mutableCopy] autorelease];
else
{
CGImageDestinationAddImageFromSource(destination, source, 0, (CFDictionaryRef) metadataAsMutable);
BOOL success = CGImageDestinationFinalize(destination);
if(!success)
dest_data = [[data mutableCopy] autorelease];
}
if(destination)
CFRelease(destination); CFRelease(source); return dest_data;
}

and We will retrieve that data like this

//FOR CAMERA IMAGE
NSData *originalImgData = [self getImageWithMetaData:imgOriginal]; //FOR PHOTO LIBRARY IMAGE
[self getImagedataPhotoLibrary:[[myasset defaultRepresentation] metadata] andImage:imgOriginal];

For all of this you should have to Import AssetsLibrary.framework and ImageIO.framework.

answered Mar 27 '12 at 13:26

iOS developer
8,688124776
 
    
where is currentLatitude
coming from? Are you setting this from the standard CoreLocation calls
before you invoke the UIImagePicker or are you reading it directly from
the image that was returned?
– 
Paul Cezanne
Apr 24 '12 at 14:55
    
CoreLoation calls before invoking UIImagePickerController
– 
iOS developer
Apr 25 '12 at 4:17
    
ahhh, it can be inaccurate
then. You call CoreLocation, invoke UIImagePicker and then physically
move the device a distance before taking the image. You will now have
inaccurate latitude and longitude. Drat...
– 
Paul Cezanne
Apr 25 '12 at 8:48
    
But you can also put distance filter for 5 meters so If use moves then It will automatically take its current location..
– 
iOS developer
Apr 25 '12 at 9:44
    
but you'll never know the
location when the shutter button is pressed, just the current location.
(You can keep on moving after the shutter button is pressed.)
– 
Paul Cezanne
Apr 25 '12 at 9:54

These answers all seem extremely complex. If the image has been saved
to the Camera Roll, and you have the ALAsset (either from UIImagePicker
or ALAssetLibrary) you can get the metadata like so:

asset.defaultRepresentation.metadata;

If you want to save that image from camera roll to another location (say in Sandbox/Documents) simply do:

CGImageDestinationRef imageDestinationRef   = CGImageDestinationCreateWithURL((__bridge CFURLRef)urlToSaveTo, kUTTypeJPEG, 1, NULL);
CFDictionaryRef imagePropertiesRef = (__bridge CFDictionaryRef)asset.defaultRepresentation.metadata; CGImageDestinationAddImage(imageDestinationRef, asset.defaultRepresentation.fullResolutionImage, imagePropertiesRef);
if (!CGImageDestinationFinalize(imageDestinationRef)) NSLog(@"Failed to copy photo on save to %@", urlToSaveTo); CFRelease(imageDestinationRef);
answered Mar 13 '13 at 23:19
Andrew Theis
829512
 
1  
This is a far superior way to do this than the answers from 2012.
– 
broughten
Oct 18 '13 at 6:13
1  
It also return much more info than the other ways: They won't return infos Stored in {TIFF} like Model, Make, Copyright, Artist and so on. This should be marked as answer!
– 
Benedikt Mokroß
Dec 7 '13 at 17:02

You need ALAssetsLibrary to actually retrieve the EXIF info from an
image. The EXIF is added to an image only when it is saved to the Photo
Library. Even if you use ALAssetLibrary to get an image asset from the
library, it will lose all EXIF info if you set it to a UIImage.

answered Dec 13 '12 at 13:24

ATOzTOA
9,17042158
 

I have tried to insert GPS coordinates into image metadata picked by iPad Camera as it was suggested by Mehul.
It Works, Thank you for your post.

P.S.
Who intends to use that code, just substitude the two geolocations at
the top of the function -(NSMutableData *)getImageWithMetaData:(UIImage
*)pImage {

double currentLatitude = [locationManager location].coordinate.latitude;
double currentLongitude = [locationManager location].coordinate.longitude;

...

By supposing that you have already initializied somewhere locationManager in your code, like this:

    locationManager = [[CLLocationManager alloc] init];
[locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
[locationManager setDelegate:self]; // Not necessary in this case
[locationManager startUpdatingLocation]; // Not neccessary in this case

and by importing CoreLocation/CoreLocation.h and ImageIO/ImageIO.h headers with associated frameworks.

 

获取图片的metaData的更多相关文章

  1. jsoup获取图片示例

    import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.Inp ...

  2. 【记录】JS 获取图片原始尺寸-防止图片溢出

    示例代码: <div id="div_content"> <img src="http://static.cnblogs.com/images/logo ...

  3. C#获取图片的后缀名

    最近在学习过程中遇到一个问题,就是如何获取图片的格式,对于一张知道全路径的照片,如果其路径包含后缀名的话,要取得后缀名,只需要一行代码即可: var ext = System.IO.Path.GetE ...

  4. js和jquery如何获取图片真实的宽度和高度

    按照插入的图片的尺寸来判断图片是横图还是竖图.然后判断过后给予不同的展示方式,下面为大家介绍下js和jquery如何获取图片真实的宽度和高度   1.什么时候需要获取图片真实的宽度和高度 在做pc网页 ...

  5. 限制Xamarin获取图片的大小

    限制Xamarin获取图片的大小在App开发中,经常会使用网络图片.因为这样不仅可以减少App的大小,还可以动态更新图片.但是手机使用网络环境千差万别.当网络环境不是理想的情况下,加载网络图片就是一个 ...

  6. js和jquery获取图片真实的宽度和高度

    1.什么时候需要获取图片真实的宽度和高度 在做pc网页的时候,有时候会考虑按照插入的图片的尺寸来判断图片是横图还是竖图.然后判断过后给予不同的展示方式! 另外一种就是在手机页面上,在新闻页插入的图片往 ...

  7. java获取图片原始尺寸

    java获取图片原始尺寸 URL url = null; InputStream is = null; BufferedImage img = null; try { url = new URL(pi ...

  8. Js获取图片原始宽高

    如果我们页面看到的图片都是缩略图,那就需要做个图片点击放大效果,那么怎样获取图片的原始宽高呢?方法如下: //获取图片原始宽度 function getNaturalWidthAndHeight(im ...

  9. 获取图片工具类:BitmapUtil

    package com.example.administrator.filemanager.utils;import android.content.Context;import android.gr ...

随机推荐

  1. jdk1.8以前不建议使用其自带的Base64来加解密

    JDK1.8之前的base64是内部测试使用的代码,不建议生产环境使用,而且未来可能会移除, JDK1.8提供最新可以正式使用的Base64类, 不要使用JDK中自带的sun.misc.BASE64D ...

  2. 学习笔记---log4j的使用与配置

    Log4j由三个重要的组件构成:日志信息的优先级,日志信息的输出目的地,日志信息的输出格式. 日志信息的优先级从高到低有OFF.FATAL.ERROR.WARN.INFO.DEBUG.ALL,分别用来 ...

  3. 域名(Domain Name)

    是由一串用点分隔的名字组成的Internet上某一台计算机或计算机组的名称,用于在数据传输时标识计算机的电子方位(有时也指地理位置,地理上的域名,指代有行政自主权的一个地方区域). 域名是一个IP地址 ...

  4. C# 代码占用的空间

    是不是代码会占用空间,如果一个程序初始化需要 100M 的代码,那么在他初始化之后,这些代码就没有作用了,他会不会占空间?本文经过测试发现,代码也是会占空间. 我写了2k个垃圾类代码,然后把他放在一个 ...

  5. javascript面向对象的常见写法与优缺点

    我们通过表单验证的功能,来逐步演进面向对象的方式.   对于刚刚接触javascript的朋友来说,如果要写一个验证用户名,密码,邮箱的功能, 一般可能会这么写: //表单验证 var checkUs ...

  6. java集合(List集合与Map集合的数据转换)

    List集合与Map集合的数据转换 实现List和Map数据的转换. 具体要求如下: 功能1:定义方法public void listToMap( ){ }将List中Student元素封装到Map中 ...

  7. Docker for Windows(三)Docker镜像与容器的区别&常用命令

    Docker镜像(Image)是一堆只读文件(read-only layer),容器(container)的定义和镜像(image)几乎一模一样,也是一堆层的统一视角,唯一区别在于容器的最上面那一层是 ...

  8. 转:xdebug在linux下的安装教程

    原文:xdebug在linux下的安装教程 [注意,本人是PHP7.1.7 Nginx ,第7步没有做,但是xdebug.so就已经在PHP的扩展文件夹里面了.目录是phpinfo的extension ...

  9. 关于vue2用vue-cli搭建环境后域名代理的http-proxy-middleware解决api接口跨域问题

    在vue中用http-proxy-middleware来进行接口代理,比如:本地运行环境为http://localhost:8080但真实访问的api为 http://www.baidu.com这时我 ...

  10. check选择样式

    样式一(H5): <form action="#">  <div class="wrapper">    <div class=& ...