我使用AVAssetReader
从视频文件逐个获取帧缓冲区,然后在帧上执行一些操作,然后使用AVAssetWritter
将新帧保存到临时文件。现在我有临时文件路径,其中保存了所有新帧逐个。 有没有什么方法可以在时间帧上播放视频不断添加到临时文件?使用AVPlayer播放视频
这里是代码从临时路径播放视频(如肋骨不断增加)
- (void)loadAssetFromFile {
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:[NSURL fileURLWithPath:[(mMediaReader.mCameraRecorder) tempVideoFilePath ]] options:nil];
NSString *tracksKey = @"tracks";
[asset loadValuesAsynchronouslyForKeys:[NSArray arrayWithObject:tracksKey] completionHandler:
^{
// Completion handler block.
dispatch_async(dispatch_get_main_queue(),
^{
NSError *error = nil;
AVKeyValueStatus status = [asset statusOfValueForKey:tracksKey error:&error];
if (status == AVKeyValueStatusLoaded) {
self.mPlayerItem = [AVPlayerItem playerItemWithAsset:asset];
[mPlayerItem addObserver:self forKeyPath:@"status"
options:0 context:&ItemStatusContext];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(playerItemDidReachEnd:)
name:AVPlayerItemDidPlayToEndTimeNotification
object:mPlayerItem];
self.mPlayer = [AVPlayer playerWithPlayerItem:mPlayerItem];
[mPlayerView setPlayer:mPlayer];
[self play:nil];
}
else {
// You should deal with the error appropriately.
NSLog(@"The asset's tracks were not loaded:\n%@", [error localizedDescription]);
}
});
}];
}
- (IBAction)play:sender {
[mPlayer play];
}
和代码从未运行块内。
寻找你的建议? – iOSPawan 2011-12-27 05:34:41
仍在为此寻求解决方案 – iOSPawan 2011-12-27 09:51:27
它看起来像'loadValuesAsynchronouslyForKeys:completionHandler:'是'AVMetaDataItem'上的方法,而不是'AVURLAsset'或'AVAsset'。你能确认'NSURL'对象不是'nil'吗? – sho 2011-12-29 21:41:57