如何在iOS上捕获的视频中添加水印 [英] How can I add a watermark in a captured video on iOS

问题描述

我想知道是否有人能告诉我如何实现这一目标。如果想到几个解决方案：

I was wondering if anybody can tell me how I can achieve this. If been thinking of a couple of solutions:

1. 从捕获的视频中创建单独的图像，然后在每个图像中合并它们之后创建一个新的AVAsset ...听起来有点复杂你不觉得吗？

1. Create individual images from the captured video and later merge them per image and after that create a new AVAsset... Sounds a bit complicated don't you think?

合并2个视频，一个是透明的（一个拿着水印）和另一个是用相机拍摄的资产。

Merge 2 videos, one is transparent (the one holding the watermark) and the other is the asset captured with the camera.

推荐答案

此代码为在视频上添加文字或字符串，保存视频后，您将在任何播放器上播放。
此代码的最大优点是提供带声音的视频。并且所有内容都在一个代码中（即文本和图像）。

This code is add a text or string ON the video and after saving video you will play on any player. Most Advantage of this code is Provide video with sound. And all things in one code(that is text and image).

#import <AVFoundation/AVFoundation.h>

-(void)MixVideoWithText
{
    AVURLAsset* videoAsset = [[AVURLAsset alloc]initWithURL:url options:nil];
    AVMutableComposition* mixComposition = [AVMutableComposition composition];

    AVMutableCompositionTrack *compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
    AVAssetTrack *clipVideoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
    AVMutableCompositionTrack *compositionAudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
    AVAssetTrack *clipAudioTrack = [[videoAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];
    //If you need audio as well add the Asset Track for audio here

    [compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, videoAsset.duration) ofTrack:clipVideoTrack atTime:kCMTimeZero error:nil];
    [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, videoAsset.duration) ofTrack:clipAudioTrack atTime:kCMTimeZero error:nil];

    [compositionVideoTrack setPreferredTransform:[[[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] preferredTransform]];

    CGSize sizeOfVideo=[videoAsset naturalSize];

    //TextLayer defines the text they want to add in Video
    //Text of watermark 
    CATextLayer *textOfvideo=[[CATextLayer alloc] init];
    textOfvideo.string=[NSString stringWithFormat:@"%@",text];//text is shows the text that you want add in video.
    [textOfvideo setFont:(__bridge CFTypeRef)([UIFont fontWithName:[NSString stringWithFormat:@"%@",fontUsed] size:13])];//fontUsed is the name of font
    [textOfvideo setFrame:CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height/6)];
    [textOfvideo setAlignmentMode:kCAAlignmentCenter];
    [textOfvideo setForegroundColor:[selectedColour CGColor]];

    //Image of watermark 
    UIImage *myImage=[UIImage imageNamed:@"one.png"];
    CALayer layerCa = [CALayer layer];
    layerCa.contents = (id)myImage.CGImage;
    layerCa.frame = CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height); 
    layerCa.opacity = 1.0; 

    CALayer *optionalLayer=[CALayer layer];
    [optionalL addSublayer:textOfvideo];
    optionalL.frame=CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height);
    [optionalL setMasksToBounds:YES];

    CALayer *parentLayer=[CALayer layer];
    CALayer *videoLayer=[CALayer layer];
    parentLayer.frame=CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height);
    videoLayer.frame=CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height);
    [parentLayer addSublayer:videoLayer];
    [parentLayer addSublayer:optionalLayer];
    [parentLayer addSublayer:layerCa];

    AVMutableVideoComposition *videoComposition=[AVMutableVideoComposition videoComposition] ;
    videoComposition.frameDuration=CMTimeMake(1, 30);
    videoComposition.renderSize=sizeOfVideo;
    videoComposition.animationTool=[AVVideoCompositionCoreAnimationTool videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer];

    AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
    instruction.timeRange = CMTimeRangeMake(kCMTimeZero, [mixComposition duration]);
    AVAssetTrack *videoTrack = [[mixComposition tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
    AVMutableVideoCompositionLayerInstruction* layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:videoTrack];
    instruction.layerInstructions = [NSArray arrayWithObject:layerInstruction];
    videoComposition.instructions = [NSArray arrayWithObject: instruction];

    NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)objectAtIndex:0];
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"yyyy-MM-dd_HH-mm-ss"];
    NSString *destinationPath = [documentsDirectory stringByAppendingFormat:@"/utput_%@.mov", [dateFormatter stringFromDate:[NSDate date]]];

    AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetMediumQuality];
    exportSession.videoComposition=videoComposition;

    exportSession.outputURL = [NSURL fileURLWithPath:destinationPath];
    exportSession.outputFileType = AVFileTypeQuickTimeMovie;
    [exportSession exportAsynchronouslyWithCompletionHandler:^{
    switch (exportSession.status)
    {
        case AVAssetExportSessionStatusCompleted:
            NSLog(@"Export OK");
            if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(destinationPath)) {
                UISaveVideoAtPathToSavedPhotosAlbum(destinationPath, self, @selector(video:didFinishSavingWithError:contextInfo:), nil);
            }
            break;
        case AVAssetExportSessionStatusFailed:
            NSLog (@"AVAssetExportSessionStatusFailed: %@", exportSession.error);
            break;
        case AVAssetExportSessionStatusCancelled:
            NSLog(@"Export Cancelled");
            break;
    }
  }];
}

显示保存视频后的错误。

Shows the error they will come after saving video.

-(void) video: (NSString *) videoPath didFinishSavingWithError: (NSError *) error contextInfo: (void *) contextInfo 
{
    if(error)
        NSLog(@"Finished saving video with error: %@", error); 
}

这篇关于如何在iOS上捕获的视频中添加水印的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！