1，首先我们要做视频导出合并这些基本的操作

   这部分代码网上都有基本都是比较简单没什么坑，首先导入视频地址，拿到AVAsset,然后利用AVMutableComposition去配置合并就行了

NSDictionary*optDict = [NSDictionarydictionaryWithObject:[NSNumbernumberWithBool:NO]forKey:AVURLAssetPreferPreciseDurationAndTimingKey];

AVAsset*firstAsset = [[AVURLAssetalloc]initWithURL:((FetchObject*)[videoArraysobjectAtIndex:0]).fileUroptions:optDict];

AVAsset*secondAsset = [[AVURLAssetalloc]initWithURL:((FetchObject*)[videoArraysobjectAtIndex:1]).fileUroptions:optDict];

AVAsset*endedAsset;

if(videoArrays.count>=3)

{

endedAsset= [[AVURLAssetalloc]initWithURL:((FetchObject*)[videoArraysobjectAtIndex:2]).fileUroptions:optDict];

}

AVMutableComposition*composition = [AVMutableCompositioncomposition];

//为视频类型的的Track

AVMutableCompositionTrack*compositionTrack = [compositionaddMutableTrackWithMediaType:AVMediaTypeVideopreferredTrackID:kCMPersistentTrackID_Invalid];

//CMTimeRangeMake 指定起去始位置

CMTimeRangefirstTimeRange =CMTimeRangeMake(kCMTimeZero, firstAsset.duration);

CMTimeRangesecondTimeRange =CMTimeRangeMake(kCMTimeZero, secondAsset.duration);

CMTimeRangeendedTimeRange=CMTimeRangeMake(kCMTimeZero, endedAsset.duration);

[compositionTrackinsertTimeRange:firstTimeRangeofTrack:[firstAssettracksWithMediaType:AVMediaTypeVideo][0]atTime:kCMTimeZeroerror:nil];

[compositionTrackinsertTimeRange:secondTimeRangeofTrack:[secondAssettracksWithMediaType:AVMediaTypeVideo][0]atTime:firstTimeRange.durationerror:nil];

if(endedAsset!=nil)

{

[compositionTrackinsertTimeRange:endedTimeRangeofTrack:[endedAssettracksWithMediaType:AVMediaTypeVideo][0]atTime:secondTimeRange.durationerror:nil];

}

//只合并视频，导出后声音会消失，所以需要把声音插入到混淆器中

//添加音频,添加本地其他音乐也可以,与视频一致

AVMutableCompositionTrack*audioTrack = [compositionaddMutableTrackWithMediaType:AVMediaTypeAudiopreferredTrackID:kCMPersistentTrackID_Invalid];

if([firstAssettracksWithMediaType:AVMediaTypeAudio].count>0)

{

[audioTrackinsertTimeRange:firstTimeRangeofTrack:[firstAssettracksWithMediaType:AVMediaTypeAudio][0]atTime:kCMTimeZeroerror:nil];

}

//CMTimeRange totalTimeRange=CMTimeRangeMake(kCMTimeZero,CMTimeAdd(CMTimeAdd(secondTimeRange.duration, firstTimeRange.duration), endedTimeRange.duration));

if([secondAssettracksWithMediaType:AVMediaTypeAudio].count>0)

{

[audioTrackinsertTimeRange:secondTimeRangeofTrack:[secondAssettracksWithMediaType:AVMediaTypeAudio][0]atTime:firstAsset.durationerror:nil];

}

if(endedAsset!=nil)

{

if([endedAssettracksWithMediaType:AVMediaTypeAudio].count>0) {

[audioTrackinsertTimeRange:endedTimeRangeofTrack:[endedAssettracksWithMediaType:AVMediaTypeAudio][0]atTime:secondAsset.durationerror:nil];

}

}

拆分配置好后可以用AVAssetExportSession 导出

exporterSession= [[AVAssetExportSessionalloc]initWithAsset:compositionpresetName:AVAssetExportPreset1280x720];

if(videoComposition!=nil) {

exporterSession.videoComposition=videoComposition;

}

exporterSession.outputFileType=AVFileTypeQuickTimeMovie;

//混合后的视频输出路径

NSString*outPutPath =MERAGVIDEOPATH;

if([[NSFileManagerdefaultManager]fileExistsAtPath:outPutPath])

{

[[NSFileManagerdefaultManager]removeItemAtPath:outPutPatherror:nil];

}

NSURL*outPutUrl = [NSURLfileURLWithPath:outPutPath];

exporterSession.outputURL= outPutUrl;//如果文件已存在，将造成导出失败

exporterSession.shouldOptimizeForNetworkUse=YES;//用于互联网传输

[exporterSessionexportAsynchronouslyWithCompletionHandler:^{

2.我们可以利用gpuimage 第三方框架做滤镜(这里面有很多坑。。)

gpuimage 是个老外写的滤镜第三方库支持图片和视频 https://github.com/BradLarson/GPUImage

首先第一个坑: 美工给你什么做滤镜，最好要你们美工导出oringal lookup table格子图 就是gpuimage里面有的让你们美工按照你们需要的滤镜调用ps导出

fitler=[[GPUImageFilteralloc]init];

self.filterLookup= [[GPUImageLookupFilteralloc]init];

self.lookupImageSource= [[GPUImagePicturealloc]initWithImage:[UIImageimageNamed:@"N1.png"]];

[self.lookupImageSourceaddTarget:self.filterLookupatTextureLocation:1];

[self.lookupImageSourceuseNextFrameForImageCapture];

[self.lookupImageSourceprocessImage];

fitler=self.filterLookup;

这样子你就可以配置出一个你需要的滤镜fitler

然后你要播放预览加了滤镜的视频

我们不能用传统的播放器，我们需要自己写一个播放器，需要用到avplayer 和avplayeritem,还有GPUImageMovie gpuimage的本地视频播放

- (void)setFitlerView:(GPUImageFilter*)fitler{

_avplayer=[[AVPlayeralloc]init];

_avplayerItem=[[AVPlayerItemalloc]initWithURL:_videoUrl];

[_avplayerreplaceCurrentItemWithPlayerItem:_avplayerItem];

[selfsetFillMode:kGPUImageFillModePreserveAspectRatioAndFill];

_movieFile=[[GPUImageMoviealloc]initWithPlayerItem:_avplayerItem];

_movieFile.url=_videoUrl;

[_movieFilesetPlayAtActualSpeed:YES];

[_movieFilesetShouldRepeat:YES];

[_movieFileaddTarget:fitler];

[fitleraddTarget:self];

[_movieFilestartProcessing];

[_avplayerplay];

}

3.添加音乐，这个用原生avfoundation,

4.添加水印动画（这里面也有很多坑。。）