这段代码在模拟器上运行良好。但是,当我尝试在iPad上运行导出时,它总是挂起进度值0.14583-ish。有人可以帮我找出原因吗?已经坚持了很长一段时间。
这是我的代码:
NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:composition];
if ([compatiblePresets containsObject:AVAssetExportPresetLowQuality]) {
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc]
initWithAsset:composition presetName:AVAssetExportPresetLowQuality];
exportSession.outputURL = [NSURL fileURLWithPath:[[ShowDAO getUserDocumentDir] stringByAppendingString:exportFilename]];
exportSession.outputFileType = AVFileTypeQuickTimeMovie;
CMTime start = CMTimeMakeWithSeconds(0, 1);
CMTime duration = CMTimeMakeWithSeconds(1000, 1);
CMTimeRange range = CMTimeRangeMake(start, duration);
exportSession.timeRange = range;
[exportSession exportAsynchronouslyWithCompletionHandler:^{
switch ([exportSession status]) {
case AVAssetExportSessionStatusCompleted:
NSLog(@"Export Completed");
break;
case AVAssetExportSessionStatusFailed:
NSLog(@"Export failed: %@", [[exportSession error] localizedDescription]);
break;
case AVAssetExportSessionStatusCancelled:
NSLog(@"Export cancelled");
break;
default:
break;
}
}];
while(exportSession.progress != 1.0){
NSLog(@"loading... : %f",exportSession.progress);
sleep(1);
}
[exportSession release];
}
答案 0 :(得分:3)
while(exportSession.progress != 1.0){
NSLog(@"loading... : %f",exportSession.progress);
sleep(1);
}
这个while循环阻塞了主线程。 NSLog可能无法正常启动。没有while循环尝试吗?