iOS中 流媒体播放和下载 韩俊强的博客

         iOS中关于流媒体的简介：介于下载本地播放与实时流媒体之间的一种播放形式，下载本地播放必须全部将文件下载完成后才能播放，而渐进式下载不必等到全部下载完成后再播放，它可以一边下载一边播放，在完成播放内容之后，整个文件会保存在手机上。

实时流媒体

实时流媒体是一边接收数据包一边播放，本地不保留文件副本，实时流式传输总是实时传送，可以实时实况转播，支持随机访问，用户可以快进或者快退以观看前面或后面的内容。实时流媒体传输必须保证数据包的传输速度大于文件的播放速度，否则用户看到的视频会出现暂停。当网络堵塞情况下视频质量会下降，所以要想保证视频的质量渐进式下载会更好一些。

下面是本人亲测的流媒体播放和下载教程：

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝

1.界面搭建（如图）

2.用到的第三方助手类（需要的可以微博互动或私信我）

下载地址：http://pan.baidu.com/s/1hrvqXA8

3.开始项目－头文件及相关宏

LO_ViewController.h

#import <UIKit/UIKit.h>
#import <MediaPlayer/MediaPlayer.h>
#import "M3U8Handler.h"
#import "VideoDownloader.h"
#import "HTTPServer.h"

@interface LO_ViewController : UIViewController<M3U8HandlerDelegate,VideoDownloadDelegate>

@property (nonatomic, strong)HTTPServer * httpServer;
@property (nonatomic, strong)VideoDownloader *downloader;

@end

LO_ViewController.m

#import "LO_ViewController.h"

@interface LO_ViewController ()

@property (weak, nonatomic) IBOutlet UIProgressView *progressView;

@property (weak, nonatomic) IBOutlet UILabel *progressLabel;

@property (weak, nonatomic) IBOutlet UIButton *downloadButton;

@property (weak, nonatomic) IBOutlet UIButton *clearButton;

@end

@implementation LO_ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
    
    //打开本地服务器
    [self openHttpServer];
    
    if ([[[NSUserDefaults standardUserDefaults] objectForKey:@"isDownload"] boolValue]) {
        [self.downloadButton setTitle:@"已完成" forState:UIControlStateNormal];
        self.downloadButton.enabled = NO;
        self.clearButton.enabled = YES;
        M3U8Handler *handler = [[M3U8Handler alloc] init];
        [handler praseUrl:[NSString stringWithFormat:@"http://v.youku.com/player/getM3U8/vid/XNjUxMTE4NDAw/type/mp4"]];
        handler.playlist.uuid = @"XNjUxMTE4NDAw";
        self.downloader = [[VideoDownloader alloc]initWithM3U8List:handler.playlist];
        [self.downloader addObserver:self forKeyPath:@"clearCaches" options:NSKeyValueObservingOptionNew | NSKeyValueObservingOptionOld context:nil]; // 判断是否清理缓存
    }
    
    
}

- (void)openHttpServer
{
    self.httpServer = [[HTTPServer alloc] init];
    [self.httpServer setType:@"_http._tcp."];  // 设置服务类型
    [self.httpServer setPort:12345]; // 设置服务器端口
        
    // 获取本地Library/Cache路径下downloads路径
    NSString *webPath = [kLibraryCache stringByAppendingPathComponent:kPathDownload];
    NSLog(@"-------------\nSetting document root: %@\n", webPath);
	
    // 设置服务器路径
	[self.httpServer setDocumentRoot:webPath];
    NSError *error;
    
	if(![self.httpServer start:&error])
	{
        NSLog(@"-------------\nError starting HTTP Server: %@\n", error);
	}
}

#pragma mark - 清理缓存
- (IBAction)clearCaches:(id)sender {
    [self.downloader cleanDownloadFiles];
}

- (IBAction)playStreamingMedia:(id)sender {
    
    // 优酷视频m3u8新地址格式如下:http://pl.youku.com/playlist/m3u8?vid=XNjUxMTE4NDAw&type=mp4
    // 如果上面的链接不可用，那么使用这个链接http://v.youku.com/player/getM3U8/vid/XNjUxMTE4NDAw/type/mp4，如果两个连接都不可以用的话，那么很大可能是优酷的服务器挂掉了
    // 如果上面的两种格式都不行的话，考虑用这个格式，当然如果这个格式不行的话，是上面的，或者直接换个对应的m3u8的地址 http://pl.youku.com/playlist/m3u8?vid=162779600&ts=1407469897&ctype=12&token=3357&keyframe=1&sid=640746989782612d6cc70&ev=1&type=mp4&ep=dCaUHU2LX8YJ4ivdjj8bMyqxJ3APXP8M9BiCiNRiANQnS%2B24&oip=2043219268
    NSURL *url = [[NSURL alloc] initWithString:@"http://pl.youku.com/playlist/m3u8?vid=162779600&ts=1407469897&ctype=12&token=3357&keyframe=1&sid=640746989782612d6cc70&ev=1&type=flv&ep=dCaUHU2LX8YJ4ivdjj8bMyqxJ3APXP8M9BiCiNRiANQnS%2B24&oip=2043219268"];
    MPMoviePlayerViewController *player = [[MPMoviePlayerViewController alloc] initWithContentURL:url];
    
    [self presentMoviePlayerViewControllerAnimated:player];
    
}

- (IBAction)downloadStreamingMedia:(id)sender {
    
    UIButton *downloadButton = sender;
    
    // 获取本地Library/Cache路径
    NSString *localDownloadsPath = [kLibraryCache stringByAppendingPathComponent:kPathDownload];
    // 获取视频本地路径
    NSString *filePath = [localDownloadsPath stringByAppendingPathComponent:@"XNjUxMTE4NDAw/movie.m3u8"];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    
    // 判断视频是否缓存完成，如果完成则播放本地缓存
    if ([fileManager fileExistsAtPath:filePath]) {
        [downloadButton setTitle:@"已完成" forState:UIControlStateNormal];
        downloadButton.enabled = NO;
    
    }else{
        M3U8Handler *handler = [[M3U8Handler alloc] init];
        handler.delegate = self;
        // 解析m3u8视频地址
        [handler praseUrl:@"http://pl.youku.com/playlist/m3u8?vid=162779600&ts=1407469897&ctype=12&token=3357&keyframe=1&sid=640746989782612d6cc70&ev=1&type=flv&ep=dCaUHU2LX8YJ4ivdjj8bMyqxJ3APXP8M9BiCiNRiANQnS%2B24&oip=2043219268"];
        
        // 开启网络指示器
        [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES];
    }
}

- (IBAction)playVideoFromLocal:(id)sender {
    
    NSString * playurl = [NSString stringWithFormat:@"http://127.0.0.1:12345/XNjUxMTE4NDAw/movie.m3u8"];
    NSLog(@"本地视频地址-----%@", playurl);
    
    // 获取本地Library/Cache路径
    NSString *localDownloadsPath = [kLibraryCache stringByAppendingPathComponent:kPathDownload];
    // 获取视频本地路径
    NSString *filePath = [localDownloadsPath stringByAppendingPathComponent:@"XNjUxMTE4NDAw/movie.m3u8"];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    
    // 判断视频是否缓存完成，如果完成则播放本地缓存
    if ([fileManager fileExistsAtPath:filePath]) {
        MPMoviePlayerViewController *playerViewController =[[MPMoviePlayerViewController alloc]initWithContentURL:[NSURL URLWithString: playurl]];
        [self presentMoviePlayerViewControllerAnimated:playerViewController];
    }
    else{
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Sorry" message:@"当前视频未缓存" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
        [alertView show];
    }
}

#pragma mark -
#pragma mark - 视频解析完成
-(void)praseM3U8Finished:(M3U8Handler*)handler
{
    handler.playlist.uuid = @"XNjUxMTE4NDAw";
    self.downloader = [[VideoDownloader alloc]initWithM3U8List:handler.playlist];
    [self.downloader addObserver:self forKeyPath:@"currentProgress" options:NSKeyValueObservingOptionNew | NSKeyValueObservingOptionOld context:nil]; // 设置观察者用来得到当前下载的进度
    [self.downloader addObserver:self forKeyPath:@"clearCaches" options:NSKeyValueObservingOptionNew | NSKeyValueObservingOptionOld context:nil]; // 判断是否清理缓存
    self.downloader.delegate = self;
    [self.downloader startDownloadVideo]; // 开始下载
}

#pragma mark - 通过观察者监控下载进度显示/缓存清理

-(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
    if ([keyPath isEqualToString:@"clearCaches"]) {
        self.downloadButton.enabled = YES;
        [self.downloadButton setTitle:@"下载" forState:UIControlStateNormal];
        self.clearButton.enabled = NO;
        [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithBool:NO] forKey:@"isDownload"];
        [[NSUserDefaults standardUserDefaults] synchronize];
        self.progressView.progress = 0.0;
        self.progressLabel.text = [NSString stringWithFormat:@"%.2f%%", 0.0];
    }else{
        self.progressLabel.text = [NSString stringWithFormat:@"%.2f%%", 100 * [[change objectForKey:@"new"] floatValue]];
        self.progressView.progress = [[change objectForKey:@"new"] floatValue];
        if (self.progressView.progress == 1) {
            [[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithBool:YES] forKey:@"isDownload"];
            [self.downloadButton setTitle:@"已完成" forState:UIControlStateNormal];
            [[NSUserDefaults standardUserDefaults] synchronize];
            self.clearButton.enabled = YES;
            self.downloadButton.enabled = NO;
        }
    }
    
}

#pragma mark - 视频解析失败
-(void)praseM3U8Failed:(M3U8Handler*)handler
{
    NSLog(@"视频解析失败-failed -- %@",handler);
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"噢,NO~