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Ho usato il codice seguente per aggiungere la sovrapposizione di immagini sul video e quindi esportare il nuovo video generato nella directory del documento. Ma stranamente, il video viene ruotato di 90 gradi.AVMutableVideoComposizione di video ruotato catturato in modalità verticale
- (void)buildTransitionComposition:(AVMutableComposition *)composition andVideoComposition:(AVMutableVideoComposition *)videoComposition
{
CMTime nextClipStartTime = kCMTimeZero;
NSInteger i;
// Make transitionDuration no greater than half the shortest clip duration.
CMTime transitionDuration = self.transitionDuration;
for (i = 0; i < [_clips count]; i++) {
NSValue *clipTimeRange = [_clipTimeRanges objectAtIndex:i];
if (clipTimeRange) {
CMTime halfClipDuration = [clipTimeRange CMTimeRangeValue].duration;
halfClipDuration.timescale *= 2; // You can halve a rational by doubling its denominator.
transitionDuration = CMTimeMinimum(transitionDuration, halfClipDuration);
}
}
// Add two video tracks and two audio tracks.
AVMutableCompositionTrack *compositionVideoTracks[2];
AVMutableCompositionTrack *compositionAudioTracks[2];
compositionVideoTracks[0] = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
compositionVideoTracks[1] = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
compositionAudioTracks[0] = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
compositionAudioTracks[1] = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
CMTimeRange *passThroughTimeRanges = alloca(sizeof(CMTimeRange) * [_clips count]);
CMTimeRange *transitionTimeRanges = alloca(sizeof(CMTimeRange) * [_clips count]);
// Place clips into alternating video & audio tracks in composition, overlapped by transitionDuration.
for (i = 0; i < [_clips count]; i++) {
NSInteger alternatingIndex = i % 2; // alternating targets: 0, 1, 0, 1, ...
AVURLAsset *asset = [_clips objectAtIndex:i];
NSValue *clipTimeRange = [_clipTimeRanges objectAtIndex:i];
CMTimeRange timeRangeInAsset;
if (clipTimeRange)
timeRangeInAsset = [clipTimeRange CMTimeRangeValue];
else
timeRangeInAsset = CMTimeRangeMake(kCMTimeZero, [asset duration]);
AVAssetTrack *clipVideoTrack = [[asset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
[compositionVideoTracks[alternatingIndex] insertTimeRange:timeRangeInAsset ofTrack:clipVideoTrack atTime:nextClipStartTime error:nil];
/*
CGAffineTransform t = clipVideoTrack.preferredTransform;
NSLog(@"Transform1 : %@",t);
*/
AVAssetTrack *clipAudioTrack = [[asset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];
[compositionAudioTracks[alternatingIndex] insertTimeRange:timeRangeInAsset ofTrack:clipAudioTrack atTime:nextClipStartTime error:nil];
// Remember the time range in which this clip should pass through.
// Every clip after the first begins with a transition.
// Every clip before the last ends with a transition.
// Exclude those transitions from the pass through time ranges.
passThroughTimeRanges[i] = CMTimeRangeMake(nextClipStartTime, timeRangeInAsset.duration);
if (i > 0) {
passThroughTimeRanges[i].start = CMTimeAdd(passThroughTimeRanges[i].start, transitionDuration);
passThroughTimeRanges[i].duration = CMTimeSubtract(passThroughTimeRanges[i].duration, transitionDuration);
}
if (i+1 < [_clips count]) {
passThroughTimeRanges[i].duration = CMTimeSubtract(passThroughTimeRanges[i].duration, transitionDuration);
}
// The end of this clip will overlap the start of the next by transitionDuration.
// (Note: this arithmetic falls apart if timeRangeInAsset.duration < 2 * transitionDuration.)
nextClipStartTime = CMTimeAdd(nextClipStartTime, timeRangeInAsset.duration);
nextClipStartTime = CMTimeSubtract(nextClipStartTime, transitionDuration);
// Remember the time range for the transition to the next item.
transitionTimeRanges[i] = CMTimeRangeMake(nextClipStartTime, transitionDuration);
}
// Set up the video composition if we are to perform crossfade or push transitions between clips.
NSMutableArray *instructions = [NSMutableArray array];
// Cycle between "pass through A", "transition from A to B", "pass through B", "transition from B to A".
for (i = 0; i < [_clips count]; i++) {
NSInteger alternatingIndex = i % 2; // alternating targets
// Pass through clip i.
AVMutableVideoCompositionInstruction *passThroughInstruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
passThroughInstruction.timeRange = passThroughTimeRanges[i];
AVMutableVideoCompositionLayerInstruction *passThroughLayer = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:compositionVideoTracks[alternatingIndex]];
/*
CGAffineTransform rotationTransform = CGAffineTransformMakeRotation(M_PI_2);
CGAffineTransform rotateTranslate = CGAffineTransformTranslate(rotationTransform,320,0);
[passThroughLayer setTransform:rotateTranslate atTime:kCMTimeZero];
*/
passThroughInstruction.layerInstructions = [NSArray arrayWithObject:passThroughLayer];
[instructions addObject:passThroughInstruction];
if (i+1 < [_clips count]) {
// Add transition from clip i to clip i+1.
AVMutableVideoCompositionInstruction *transitionInstruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
transitionInstruction.timeRange = transitionTimeRanges[i];
AVMutableVideoCompositionLayerInstruction *fromLayer = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:compositionVideoTracks[alternatingIndex]];
AVMutableVideoCompositionLayerInstruction *toLayer = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:compositionVideoTracks[1-alternatingIndex]];
if (self.transitionType == SimpleEditorTransitionTypeCrossFade) {
// Fade out the fromLayer by setting a ramp from 1.0 to 0.0.
[fromLayer setOpacityRampFromStartOpacity:1.0 toEndOpacity:0.0 timeRange:transitionTimeRanges[i]];
}
else if (self.transitionType == SimpleEditorTransitionTypePush) {
// Set a transform ramp on fromLayer from identity to all the way left of the screen.
[fromLayer setTransformRampFromStartTransform:CGAffineTransformIdentity toEndTransform:CGAffineTransformMakeTranslation(-composition.naturalSize.width, 0.0) timeRange:transitionTimeRanges[i]];
// Set a transform ramp on toLayer from all the way right of the screen to identity.
[toLayer setTransformRampFromStartTransform:CGAffineTransformMakeTranslation(+composition.naturalSize.width, 0.0) toEndTransform:CGAffineTransformIdentity timeRange:transitionTimeRanges[i]];
}
transitionInstruction.layerInstructions = [NSArray arrayWithObjects:fromLayer, toLayer, nil];
[instructions addObject:transitionInstruction];
}
}
videoComposition.instructions = instructions;
}
Si prega di aiuto, in quanto non sono in grado di esportare il video in modalità corretta. Qualsiasi aiuto apprezzato. Grazie.
ho provato questo metodo, ma la sua non essere chiamato durante execution.Can La prego di approfondire è utile, un po 'di più. Grazie. :) – Dhruv
Il mio turno è completamente nero. Puoi per favore aiutarmi perché? – itsji10dra
sarebbe bello se potessi dare il codice swift 3 per quello. –