iOS

//

//  AVMetadataInfo.h

//  AVMetadata

//

//  Created by Wengrp on 15/10/27.

//  Copyright © 2015年 Wengrp. All rights reserved.

//

#import <UIKit/UIKit.h>

#import <Foundation/Foundation.h>

#import <AVFoundation/AVFoundation.h>

@interface AVMetadataInfo : NSObject

/**

 获取音视频文件的Metadata信息(可以获取到mp3以及m4a的相关信息)

 

 *AVMetadataCommonKeyArtwork这个参数是可以换的,换不同的参数可以取得不同的值

 

 *[注意]此方法中用到了信号量将异步操作转换成了同步操作,尽量在主线程中使用

 

 @param fileURL 文件的URL地址

 @return 一个包含了相关内容的字典

 */

+ (NSDictionary *)dataInfoFromFileURL:(NSURL *)fileURL;

@end

 

//

//  AVMetadataInfo.m

//  AVMetadata

//

//  Created by Wengrp on 15/10/27.

//  Copyright © 2015年 Wengrp. All rights reserved.

//

 

#import "AVMetadataInfo.h"

 

@implementation AVMetadataInfo

+ (NSDictionary *)dataInfoFromFileURL:(NSURL *)fileURL

{

    // 创建字典

    NSMutableDictionary *dic = [NSMutableDictionary dictionary];

    

    // 创建信号量(将异步变成同步)

    dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);

    

    AVAsset *asset = [AVURLAsset URLAssetWithURL:fileURL options:nil];

    [asset loadValuesAsynchronouslyForKeys:@[@"commonMetadata"]

                         completionHandler:^{

                             // 发送信号量

                             dispatch_semaphore_signal(semaphore);

                         }];

    

    // 无限等待

    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);

    

    // 获取数据

    NSArray *artworks = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata

                                                       withKey:AVMetadataCommonKeyArtwork

                                                      keySpace:AVMetadataKeySpaceCommon];

    for (AVMetadataItem *item in artworks)

    {

        if ([item.keySpace isEqualToString:AVMetadataKeySpaceID3])

        {

            NSDictionary *dict = [item.value copyWithZone:nil];

            

            // 获取图片

            

            UIImage  *image = [UIImage imageWithData:[dict objectForKey:@"data"]];

            [dic setObject:image forKey:@"Artwork"];

        }

        if ([item.keySpace isEqualToString:AVMetadataKeySpaceiTunes])

        {

            // 获取图片

            UIImage *image = [UIImage imageWithData:[item.value copyWithZone:nil]];

            [dic setObject:image forKey:@"Artwork"];

        }

    }

    

    return [NSDictionary dictionaryWithDictionary:dic];

}

 

@end