我创建了一种根据给定时间范围修剪和导出视频的方法。它还将视频旋转为横向。
但由于某种原因,在尝试处理之前使用 UIVideoEditorController 修剪的视频时,AVAssetExportSession 失败。
以前有人遇到过这个问题吗?
我收到此错误:
AVAssetExportSessionStatusFailed: Error Domain=AVFoundationErrorDomain Code=-11841 "The operation couldn’t be completed. (AVFoundationErrorDomain error -11841.)"
对于这种方法:
- (void) trimVideoWithRange: (CMTimeRange)range fromInputURL: (NSURL *)inputURL withCompletionHandler:(void (^)(BOOL success, NSURL *outputURL))handler;
{
AVAsset *asset = [AVURLAsset assetWithURL:inputURL];
AVAssetTrack *videoTrack = [asset tracksWithMediaType:AVMediaTypeVideo][0];
AVAssetTrack *audioTrack = [asset tracksWithMediaType:AVMediaTypeAudio][0];
NSLog(@"%@, %@, %@", asset, videoTrack, audioTrack);
NSError *error;
// Create a video composition
AVMutableComposition *composition = [AVMutableComposition composition];
AVMutableCompositionTrack *videoCompositionTrack = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
error = nil;
[videoCompositionTrack insertTimeRange:videoTrack.timeRange ofTrack:videoTrack atTime:CMTimeMakeWithSeconds(0, NSEC_PER_SEC) error:&error];
NSLog(@"videoCompositionTrack timeRange: %lld, %lld", videoCompositionTrack.timeRange.start.value, videoCompositionTrack.timeRange.duration.value);
if(error)
NSLog(@"videoCompositionTrack error: %@", error);
AVMutableCompositionTrack *audioCompositionTrack = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
error = nil;
[audioCompositionTrack insertTimeRange:audioTrack.timeRange ofTrack:audioTrack atTime:CMTimeMakeWithSeconds(0, NSEC_PER_SEC) error:&error];
NSLog(@"audioCompositionTrack timeRange: %lld, %lld", audioCompositionTrack.timeRange.start.value, audioCompositionTrack.timeRange.duration.value);
if(error)
NSLog(@"audioCompositionTrack error: %@", error);
// Rotate video if needed
CGAffineTransform rotationTransform = videoTrack.preferredTransform;
// Create video composition
AVMutableVideoComposition *videoComposition = [AVMutableVideoComposition videoComposition];
videoComposition.renderScale = 1.0;
videoComposition.renderSize = videoTrack.naturalSize;
videoComposition.frameDuration = CMTimeMake(1, 30);
// Apply the transform which may have been changed
AVMutableVideoCompositionLayerInstruction *instruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:videoTrack];
[instruction setTransform:rotationTransform atTime:kCMTimeZero];
// Set the time range and layer instructions for the video composition
AVMutableVideoCompositionInstruction *videoTrackInstruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
videoTrackInstruction.layerInstructions = [NSArray arrayWithObject:instruction];
videoTrackInstruction.timeRange = range;
videoComposition.instructions = @[videoTrackInstruction];
// Check so that we can proceed with our desired output preset
NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:composition];
if (![compatiblePresets containsObject:AVAssetExportPreset960x540])
{
// Nope.
if(handler)
handler(NO, nil);
return;
}
// Create export session with composition
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:composition presetName:AVAssetExportPreset960x540];
// Configure export session
exportSession.outputURL = [NSURL fileURLWithPath:pathToTemporaryOutput];
exportSession.outputFileType = AVFileTypeQuickTimeMovie;
exportSession.videoComposition = videoComposition;
exportSession.shouldOptimizeForNetworkUse = YES;
// Export async
[exportSession exportAsynchronouslyWithCompletionHandler:^{
switch ([exportSession status])
{
case AVAssetExportSessionStatusCompleted:
{
dispatch_async(dispatch_get_main_queue(), ^{
// Everything OK. Execute completion block with URL to rendered video
if(handler)
handler(exportSession.status == AVAssetExportSessionStatusCompleted, [NSURL fileURLWithPath:pathToTemporaryOutput]);
});
}
break;
case AVAssetExportSessionStatusFailed:
{
NSError *exportError = exportSession.error;
NSLog(@"AVAssetExportSessionStatusFailed: %@", exportError.description);
dispatch_async(dispatch_get_main_queue(), ^{
// No go. Execute handler with fail.
if(handler)
handler(NO, nil);
});
}
break;
}
}];
}