直接上代码
+(void)addSRTWithSRTArr:(NSArray *)srtArr toVideoURL:(NSURL *)videoUrl complettion:(void (^)(NSURL *))completion
{
NSURL *outPutUrl;
//1 创建AVAsset实例 AVAsset包含了video的所有信息 self.videoUrl输入视频的路径
AVAsset *videoAsset = [AVAsset assetWithURL:videoUrl];
//2 创建AVMutableComposition实例. apple developer 里边的解释 【AVMutableComposition is a mutable subclass of AVComposition you use when you want to create a new composition from existing assets. You can add and remove tracks, and you can add, remove, and scale time ranges.】
AVMutableComposition *mixComposition = [[AVMutableComposition alloc] init];
//3 视频通道 工程文件中的轨道，有音频轨、视频轨等，里面可以插入各种对应的素材
AVMutableCompositionTrack *videoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo
preferredTrackID:kCMPersistentTrackID_Invalid];
//把视频轨道数据加入到可变轨道中 这部分可以做视频裁剪TimeRange
[videoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, videoAsset.duration)
ofTrack:[[videoAsset tracksWithMediaType:AVMediaTypeVideo] firstObject]
atTime:kCMTimeZero error:nil];
//3.1 AVMutableVideoCompositionInstruction 视频轨道中的一个视频，可以缩放、旋转等
AVMutableVideoCompositionInstruction *mainInstruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
mainInstruction.timeRange = CMTimeRangeMake(kCMTimeZero, videoAsset.duration);
// 3.2 AVMutableVideoCompositionLayerInstruction 一个视频轨道，包含了这个轨道上的所有视频素材
AVMutableVideoCompositionLayerInstruction *videolayerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:videoTrack];
AVAssetTrack *videoAssetTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo] firstObject];
UIImageOrientation videoAssetOrientation_ = UIImageOrientationUp;
BOOL isVideoAssetPortrait_ = NO;
CGAffineTransform videoTransform = videoAssetTrack.preferredTransform;
if (videoTransform.a == 0 && videoTransform.b == 1.0 && videoTransform.c == -1.0 && videoTransform.d == 0) {
videoAssetOrientation_ = UIImageOrientationRight;
isVideoAssetPortrait_ = YES;
}
if (videoTransform.a == 0 && videoTransform.b == -1.0 && videoTransform.c == 1.0 && videoTransform.d == 0) {
videoAssetOrientation_ = UIImageOrientationLeft;
isVideoAssetPortrait_ = YES;
}
if (videoTransform.a == 1.0 && videoTransform.b == 0 && videoTransform.c == 0 && videoTransform.d == 1.0) {
videoAssetOrientation_ = UIImageOrientationUp;
}
if (videoTransform.a == -1.0 && videoTransform.b == 0 && videoTransform.c == 0 && videoTransform.d == -1.0) {
videoAssetOrientation_ = UIImageOrientationDown;
}
[videolayerInstruction setTransform:videoAssetTrack.preferredTransform atTime:kCMTimeZero];
[videolayerInstruction setOpacity:0.0 atTime:videoAsset.duration];
// 3.3 - Add instructions
mainInstruction.layerInstructions = [NSArray arrayWithObjects:videolayerInstruction,nil];
//AVMutableVideoComposition：管理所有视频轨道，可以决定最终视频的尺寸，裁剪需要在这里进行
AVMutableVideoComposition *mainCompositionInst = [AVMutableVideoComposition videoComposition];
CGSize naturalSize;
if(isVideoAssetPortrait_){
naturalSize = CGSizeMake(videoAssetTrack.naturalSize.height, videoAssetTrack.naturalSize.width);
} else {
naturalSize = videoAssetTrack.naturalSize;
}
float renderWidth, renderHeight;
renderWidth = naturalSize.width;
renderHeight = naturalSize.height;
mainCompositionInst.renderSize = CGSizeMake(renderWidth, renderHeight);
mainCompositionInst.instructions = [NSArray arrayWithObject:mainInstruction];
mainCompositionInst.frameDuration = CMTimeMake(1, 30);
//加水印
// videoLayer是视频layer,parentLayer是最主要的，videoLayer和字幕，贴纸的layer都要加在该layer上
CALayer *parentLayer = [CALayer layer];
CALayer *videoLayer = [CALayer layer];
parentLayer.frame = CGRectMake(0, 0, renderWidth, renderHeight);
videoLayer.frame = CGRectMake(0, 0, renderWidth, renderHeight);
[parentLayer addSublayer:videoLayer];
for (SrtModel *srtModel in srtArr) {
UILabel *subtitleLabel = [[UILabel alloc]initWithFrame:srtModel.rect];
subtitleLabel.text = srtModel.title;
subtitleLabel.textColor = srtModel.textColor;
subtitleLabel.font = [UIFont fontWithName:srtModel.fontName size:srtModel.fontSize];
// 这个是透明度动画主要是使在插入的才显示，其它时候都是不显示的
subtitleLabel.layer.opacity = 0;
CABasicAnimation *opacityAnim = [CABasicAnimation animationWithKeyPath:@"opacity"];
opacityAnim.fromValue = [NSNumber numberWithFloat:1];
opacityAnim.toValue = [NSNumber numberWithFloat:1];
opacityAnim.removedOnCompletion = NO;
CABasicAnimation *rotationAnimation;
switch (srtModel.animationType) {
case 0:
break;
case 1:
rotationAnimation = [SubTitleAnimation moveAnimationWithFromPosition:CGPointMake(subtitleLabel.layer.position.x + 100, subtitleLabel.layer.position.y) toPosition:subtitleLabel.layer.position];
break;
case 2:
rotationAnimation = [SubTitleAnimation moveAnimationWithFromPosition:CGPointMake(subtitleLabel.layer.position.x, subtitleLabel.layer.position.y + 50) toPosition:subtitleLabel.layer.position];
break;
case 3:
rotationAnimation = [SubTitleAnimation narrowIntoAnimation];
break;
case 4:
rotationAnimation = [SubTitleAnimation fadeInAnimation];
break;
case 5:
rotationAnimation = [SubTitleAnimation transformAnimation];
break;
default:
break;
}
CAAnimationGroup *groupAnimation = [CAAnimationGroup animation];
groupAnimation.animations = [NSArray arrayWithObjects:opacityAnim, rotationAnimation, nil];
if (CMTimeGetSeconds(srtModel.insertTime.start) == 0) {
groupAnimation.beginTime = 0.01;
}else {
groupAnimation.beginTime = CMTimeGetSeconds(srtModel.insertTime.start);
}
groupAnimation.duration = CMTimeGetSeconds(srtModel.insertTime.duration);
[subtitleLabel.layer addAnimation:groupAnimation forKey:nil];
[parentLayer addSublayer:subtitleLabel.layer];
}
mainCompositionInst.animationTool = [AVVideoCompositionCoreAnimationTool
videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer];
// 4 - 输出路径
NSString *documentsDirectory = [self mp4FilePath];
NSString *myPathDocs = [documentsDirectory stringByAppendingPathComponent:
[NSString stringWithFormat:@"v_%@.mp4",[NSString dateToIDstring:[NSDate date]]]];
outPutUrl = [NSURL fileURLWithPath:myPathDocs];
// 5 - 视频文件输出
AVAssetExportSession *exporter = [[AVAssetExportSession alloc] initWithAsset:mixComposition
presetName:AVAssetExportPresetHighestQuality];
exporter.outputURL = outPutUrl;
exporter.outputFileType = AVFileTypeMPEG4;
exporter.shouldOptimizeForNetworkUse = YES;
exporter.videoComposition = mainCompositionInst;
[exporter exportAsynchronouslyWithCompletionHandler:^{
dispatch_async(dispatch_get_main_queue(), ^{
//这里是输出视频之后的操作，做你想做的
NSLog(@"完事了-----%f",[self getRealVideoAllTimeWith:outPutUrl]);
completion(outPutUrl);
});
}];
}
如需详细代码，请留言，有任何问题请指正，谢谢！