AVURLAsset 拒绝加载视频 [英] AVURLAsset refuses to load video

问题描述

我正在尝试将视频文件作为 AVURLAsset 加载到我的 iPad 应用程序中，使用异步加载的东西来等待它准备就绪.问题是，当我运行它时，我收到一条完全通用的失败"错误消息，我不知道该怎么办.如果我将它交给 MPMoviePlayerController，视频就可以工作，但是 AVURLAsset 似乎拒绝与它有任何关系.

I'm trying to load a video file into my iPad app as an AVURLAsset, using the asynchronous-loading stuff to wait for it to be ready. Problem is, when I run it, I get a completely generic "failure" error message that I have no idea what to do with. The video works if I hand it to an MPMoviePlayerController, but AVURLAsset seems to refuse to have anything to do with it.

代码:

asset = [[AVURLAsset alloc] initWithURL:[NSURL URLWithString:[docPath stringByAppendingPathComponent:@"video.mov"]] options:nil];
[asset loadValuesAsynchronouslyForKeys:[NSArray arrayWithObject:@"tracks"] completionHandler:^{
    dispatch_async(dispatch_get_main_queue(), ^{
        [self composeIfReady];
    });
}];

...

- (void)composeIfReady
{
    NSError *error = nil;
    if([asset statusOfValueForKey:@"tracks" error:&error] == AVKeyValueStatusFailed)
        NSLog(@"error loading: %@", [error description]);
    if(error == nil)
        NSLog(@"okay awesome");
}

输出:

error loading: Error Domain=AVFoundationErrorDomain Code=-11800 "The operation couldn’t be completed. (AVFoundationErrorDomain error -11800.)" UserInfo=0x1696f0 {NSUnderlyingError=0x169a40 "The operation couldn’t be completed. (OSStatus error -12936.)"}

-11800 顺便说一下，是未知错误"的错误代码.有点死胡同.有任何想法吗?在我尝试加载资产之前，我应该设置什么吗?

-11800, by the way, is the error code for "unknown error". Kind of a dead end. Any ideas? Is there something I should be setting up before I try to load the asset?

推荐答案

已解决.诀窍:使用 fileURLWithPath:，而不是 URLWithString:.显然，差异非常非常显着.

Solved. The trick: use fileURLWithPath:, not URLWithString:. Apparently the difference is really, really significant.

这篇关于AVURLAsset 拒绝加载视频的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！