iOS之GIF动画和视频帧的处理、图片转换成视频

最新推荐文章于 2021-03-30 23:13:21 发布

liyubao160

最新推荐文章于 2021-03-30 23:13:21 发布

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分类专栏： iOS/oc

本文链接：https://blog.youkuaiyun.com/u011146511/article/details/103956754

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**********基础知识：

CVPixelBufferRef 是一种像素图片类型，属于 CoreVideo 模块的，在Camera 采集返回的数据里得到一个CMSampleBufferRef，而每个CMSampleBufferRef里则包含一个 CVPixelBufferRef，在视频硬解码的返回数据里也是一个 CVPixelBufferRef。CVPixelBufferRef是iOS视频采集处理编码流程的重要中间数据媒介和纽带，理解CVPixelBufferRef有助于写出高性能可靠的视频处理。还需要学习 YUV，color range，openGL。

1.********获取gif动画中每一帧

#include <ImageIO/ImageIOBase.h>
#include <ImageIO/CGImageSource.h>

//获取gif动画的每一帧
- (NSArray *)loadGifImageArr
{
    NSURL *fileUrl = [[NSBundle mainBundle] URLForResource:@"reapanimaet" withExtension:@"gif"];
    
    CGImageSourceRef gifSource = CGImageSourceCreateWithURL((CFURLRef)fileUrl, NULL);
    size_t gifCount = CGImageSourceGetCount(gifSource);
    NSMutableArray *frames = [[NSMutableArray alloc]init];
    for (size_t i = 0; i< gifCount; i++) {
        CGImageRef imageRef = CGImageSourceCreateImageAtIndex(gifSource, i, NULL);
        UIImage *image = [UIImage imageWithCGImage:imageRef];
        [frames addObject:image];
        CGImageRelease(imageRef);
    }
    return frames;
}

2.******获取视频中的每一帧

调用：
 NSString *path = [[NSBundle mainBundle]pathForResource:@"testvideo.mov"ofType:nil];
    NSURL *url = [NSURL fileURLWithPath:path];
    [self splitVideo:url fps:24 completedBlock:^{
       
       
    }];


/**
 *  把视频文件拆成图片保存放到数组中
 *
 *  @param fileUrl        本地视频文件URL
 *  @param fps            拆分时按此帧率进行拆分
 *  @param completedBlock 所有帧被拆完成后回调
 CMTime是专门用于表示视频时间的结构体
 value不是指时间
 timescale可以理解为帧率
 获得秒数：value / timescale = seconds
 创建CMTime 用 CMTimeMake(a, b) 当前第a帧，每秒b帧
 
 */
- (void)splitVideo:(NSURL *)fileUrl fps:(float)fps completedBlock:(void(^)(void))completedBlock {
    if (!fileUrl) {
        return;
    }
    QMWNWEAKSELF;
    NSDictionary *optDict = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO] forKey:AVURLAssetPreferPreciseDurationAndTimingKey];
    AVURLAsset *avasset = [[AVURLAsset alloc] initWithURL:fileUrl options:optDict];
    
    CMTime cmtime = avasset.duration; //视频时间信息结构体
    Float64 durationSeconds = CMTimeGetSeconds(cmtime); //视频总秒数
    
    NSMutableArray *times = [NSMutableArray array];
    Float64 totalFrames = durationSeconds * fps; //获得视频总帧数
    CMTime timeFrame;
    for (int i = 1; i <= totalFrames; i++) {
        timeFrame = CMTimeMake(i, fps); //第i帧  帧率
        NSValue *timeValue = [NSValue valueWithCMTime:timeFrame];
        [times addObject:timeValue];
    }
   
    AVAssetImageGenerator *imgGenerator = [[AVAssetImageGenerator alloc] initWithAsset:avasset];
    //防止时间出现偏差
    imgGenerator.requestedTimeToleranceBefore = kCMTimeZero;
    imgGenerator.requestedTimeToleranceAfter = kCMTimeZero;
   
    NSInteger timesCount = [times count];
    [imgGenerator generateCGImagesAsynchronouslyForTimes:times completionHandler:^(CMTime requestedTime, CGImageRef  _Nullable image, CMTime actualTime, AVAssetImageGeneratorResult result, NSError * _Nullable error) {
              QMWNSTRONG;
        switch (result) {
            case AVAssetImageGeneratorCancelled:
                break;
            case AVAssetImageGeneratorFailed:
                break;
            case AVAssetImageGeneratorSucceeded: {
                UIImage *videoimage = [UIImage imageWithCGImage:image];
                [strongS.videoimageArr addObject:videoimage];
              
                if (requestedTime.value == timesCount) {
                    NSLog(@"completed");
                    if (completedBlock) {
                        completedBlock();
                    }
                }
            }
                break;
        }
    }];
}

3.******图片转换成视频

#import "ImageTovideovc.h"
#import <AVKit/AVKit.h>
#import <MediaPlayer/MediaPlayer.h>
#import <AVFoundation/AVFoundation.h>
@interface ImageTovideovc()
//未压缩的图片
@property(nonatomic,strong)  NSMutableArray*imageArr;
//经过压缩的图片
@property(nonatomic,strong) NSMutableArray*imageArray;
//视频地址
@property(nonatomic,strong)NSString*theVideoPath;
//合成进度
@property(nonatomic,strong)UILabel *progresslabel;

@property(nonatomic,assign)NSInteger  videowidth;//视频宽度
@property(nonatomic,assign)NSInteger videoheight;//视频高度
@property(nonatomic,assign)NSInteger videospeed;//播放速度，每秒多少帧
@end
@implementation ImageTovideovc
-(NSMutableArray *)imageArr{
    if(nil==_imageArr){
        _imageArr=[[NSMutableArray alloc]init];
    }
    return _imageArr;
}
-(NSMutableArray *)imageArray{
    if(nil==_imageArray){
        _imageArray=[[NSMutableArray alloc]init];
    }
    return _imageArray;
}
-(void)viewDidLoad{
    [super viewDidLoad];
    self.videowidth=self.videowidth?WIDTH:320;
    self.videoheight=self.videoheight?HEIGHT:480;
    self.videospeed=21;
    [self initDatas];
    [self initViews];
}
- (void)initViews {
 
    //视频合成按钮
    UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button setBounds:CGRectMake(0,0,WIDTH * 0.25,50)];
    button.center = CGPointMake(WIDTH * 0.25, WIDTH * 0.5);
    [button setTitle:@"视频合成"forState:UIControlStateNormal];
    [button addTarget:self action:@selector(testCompressionSession)forControlEvents:UIControlEventTouchUpInside];
    button.backgroundColor = [UIColor redColor];
    [self.view addSubview:button];
    
    //视频播放按钮
    UIButton *button1=[UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button1 setBounds:CGRectMake(0,0,WIDTH * 0.25,50)];
    button1.center = CGPointMake(WIDTH * 0.75, WIDTH * 0.5);
    [button1 setTitle:@"视频播放"forState:UIControlStateNormal];
    [button1 addTarget:self action:@selector(playAction)forControlEvents:UIControlEventTouchUpInside];
    button1.backgroundColor = [UIColor redColor];
    [self.view addSubview:button1];
    
    //视频合成播放进度提示文本框
    UILabel *lbe = [[UILabel alloc]init];
    lbe.frame = CGRectMake(0, 0, WIDTH * 0.25, 25);
    lbe.center = CGPointMake(WIDTH * 0.5, WIDTH * 0.15);
    lbe.textColor = [UIColor blackColor];
    lbe.textAlignment = NSTextAlignmentCenter;
    lbe.text = @"准备就绪";
    lbe.font = [UIFont systemFontOfSize:12];
    self.progresslabel = lbe;
    [self.view addSubview:lbe];
}
//赋值数据
- (void)initDatas{
    
    NSString *name = @"";
    UIImage *img = nil;
    
    //实先准备21张图片，命名为0.jpg至21.jpg
    for (int i = 0; i < 22; i++) {
        name = [NSString stringWithFormat:@"%d",i];
        img = [UIImage imageNamed:name];
        [self.imageArr addObject:img];
    }
    
    //对图片进行裁剪，方便合成等比例视频
    for (int i = 0; i < self.imageArr.count; i++) {
        
        UIImage *imageNew = self.imageArr[i];
        
        //设置image的尺寸
        CGSize imgeSize =  CGSizeMake(self.videowidth,self.videoheight);
        
        //对图片大小进行压缩--
        imageNew = [self imageWithImage:imageNew scaledToSize:imgeSize];
        
        [self.imageArray addObject:imageNew];
    }
}
//对图片进行压缩
-(UIImage*)imageWithImage:(UIImage*)image scaledToSize:(CGSize)newSize

{
    //    新创建的位图上下文 newSize为其大小
    UIGraphicsBeginImageContext(newSize);
    //    对图片进行尺寸的改变
    [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
    
    //    从当前上下文中获取一个UIImage对象  即获取新的图片对象
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    
    return newImage;
}
//创建视频存储路径
-(NSString *)createVideopath{
    
    
    NSString *documentPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject;

     //删除之前的路径
    if(self.theVideoPath &&![self.theVideoPath isEqualToString:@""]){

        NSString *fileName = [self.theVideoPath componentsSeparatedByString:@"/"].lastObject;
        NSString *newsPath = [documentPath stringByAppendingPathComponent:fileName];
        [[NSFileManager defaultManager]removeItemAtPath:newsPath error:nil];
        self.theVideoPath=nil;
    }
    
    return documentPath;
}
//视频合成按钮点击操作
- (void)testCompressionSession {
    QMWNWEAKSELF;
  NSString *documentPath= [self createVideopath];
    //设置mov路径
    NSString *moviePath = [documentPath  stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.mov",@"imagetovideo"]];
    self.theVideoPath=moviePath;
    //定义视频的大小320 480 倍数
    CGSize size = CGSizeMake(self.videowidth,self.videoheight);
    
    NSError *error = nil;
    
    //    转成UTF-8编码
    unlink([moviePath UTF8String]);
    
    NSLog(@"path->%@",moviePath);
    
//     iphone提供了AVFoundation库来方便的操作多媒体设备，AVAssetWriter这个类可以方便的将图像和音频写成一个完整的视频文件
    
    AVAssetWriter *videoWriter = [[AVAssetWriter alloc]initWithURL:[NSURL fileURLWithPath:moviePath]fileType:AVFileTypeQuickTimeMovie error:&error];
    
    NSParameterAssert(videoWriter);
    
    if(error) {
        NSLog(@"error =%@",[error localizedDescription]);
        return;
    }
    
    //mov的格式设置 编码格式 宽度 高度
    NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:AVVideoCodecTypeH264,AVVideoCodecKey,
                                   
                                   [NSNumber numberWithInt:size.width],AVVideoWidthKey,
                                   
                                   [NSNumber numberWithInt:size.height],AVVideoHeightKey,nil];
    
    AVAssetWriterInput *writerInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];
    
    NSDictionary *sourcePixelBufferAttributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:kCVPixelFormatType_32ARGB],kCVPixelBufferPixelFormatTypeKey,nil];
    
    //    AVAssetWriterInputPixelBufferAdaptor提供CVPixelBufferPool实例,
    //    可以使用分配像素缓冲区写入输出文件。使用提供的像素为缓冲池分配通常
    //    是更有效的比添加像素缓冲区分配使用一个单独的池
    AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput sourcePixelBufferAttributes:sourcePixelBufferAttributesDictionary];
    
    NSParameterAssert(writerInput);
    
    NSParameterAssert([videoWriter canAddInput:writerInput]);
    
    if([videoWriter canAddInput:writerInput]){
        
        NSLog(@"可以添加输入");
        
    }else{
        
        NSLog(@"不可以");
        return;
    }
    
    [videoWriter addInput:writerInput];
    
    [videoWriter startWriting];
    
    [videoWriter startSessionAtSourceTime:kCMTimeZero];
    
    //合成多张图片为一个视频文件
    
    dispatch_queue_t dispatchQueue = dispatch_queue_create("mediaInputQueue",NULL);
    
    int __block frame = 0;//第多少帧
    
    [writerInput requestMediaDataWhenReadyOnQueue:dispatchQueue usingBlock:^{
        QMWNSTRONG;
        while([writerInput isReadyForMoreMediaData]) {
            
            if(++frame >= [strongS.imageArray count] * strongS.videospeed) {
                [writerInput markAsFinished];
                
                [videoWriter finishWritingWithCompletionHandler:^{
                    NSLog(@"完成");
                    
                    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                        QMWNSTRONG;
                        strongS.progresslabel.text = @"视频合成完毕";
                        [strongS saveVideoToAlbumWith:moviePath];//保存到相册
                    }];
                }];
                break;
            }
            
            CVPixelBufferRef buffer = NULL;//像素图片类型
            int idx = frame / strongS.videospeed;//总帧数除以帧率得到第几张图
            NSLog(@"第idx==%d张图片",idx);
            NSString *progress = [NSString stringWithFormat:@"%0.2lu",idx / [self.imageArr count]];
            
            [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                QMWNSTRONG;
                strongS.progresslabel.text = [NSString stringWithFormat:@"合成进度:%@",progress];
            }];
            NSNumber *speedNum=[NSNumber numberWithInteger:strongS.videospeed];
            int speedvalue=[speedNum intValue];
            //由图片生成像素图片类型
            buffer = (CVPixelBufferRef)[strongS pixelBufferFromCGImage:[[strongS.imageArray objectAtIndex:idx]CGImage]size:size];
            if(buffer){
                //设置每秒钟播放图片的个数
                if(![adaptor appendPixelBuffer:buffer withPresentationTime:CMTimeMake(frame,speedvalue)]) {
                    NSLog(@"FAIL");
                } else {
                    NSLog(@"OK");
                    
                }
                CFRelease(buffer);
            }
        }
    }];
}
//由图片生成像素图片类型
- (CVPixelBufferRef)pixelBufferFromCGImage:(CGImageRef)image size:(CGSize)size {
    
    NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                             
                             [NSNumber numberWithBool:YES],kCVPixelBufferCGImageCompatibilityKey,
                             
                             [NSNumber numberWithBool:YES],kCVPixelBufferCGBitmapContextCompatibilityKey,nil];
    
    CVPixelBufferRef pxbuffer = NULL;
    
    CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault,size.width,size.height,kCVPixelFormatType_32ARGB,(__bridge CFDictionaryRef) options,&pxbuffer);
    
    NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);
    
    CVPixelBufferLockBaseAddress(pxbuffer,0);
    
    void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
    
    NSParameterAssert(pxdata !=NULL);
    
    CGColorSpaceRef rgbColorSpace=CGColorSpaceCreateDeviceRGB();
    
    //    当你调用这个函数的时候，Quartz创建一个位图绘制环境，也就是位图上下文。当你向上下文中绘制信息时，Quartz把你要绘制的信息作为位图数据绘制到指定的内存块。一个新的位图上下文的像素格式由三个参数决定：每个组件的位数，颜色空间，alpha选项
    
    CGContextRef context = CGBitmapContextCreate(pxdata,size.width,size.height,8,4*size.width,rgbColorSpace,kCGImageAlphaPremultipliedFirst);
    
    NSParameterAssert(context);
    
    //使用CGContextDrawImage绘制图片  这里设置不正确的话 会导致视频颠倒
    
    //    当通过CGContextDrawImage绘制图片到一个context中时，如果传入的是UIImage的CGImageRef，因为UIKit和CG坐标系y轴相反，所以图片绘制将会上下颠倒
    
    CGContextDrawImage(context,CGRectMake(0,0,CGImageGetWidth(image),CGImageGetHeight(image)), image);
    
    // 释放色彩空间
    
    CGColorSpaceRelease(rgbColorSpace);
    
    // 释放context
    
    CGContextRelease(context);
    
    // 解锁pixel buffer
    
    CVPixelBufferUnlockBaseAddress(pxbuffer,0);
    
    return pxbuffer;
}

//视频播放按钮点击操作
- (void)playAction {
    
    NSLog(@"************%@",self.theVideoPath);
    
    // 文件管理器
    NSFileManager *fileManager = [[NSFileManager alloc]init];
    
    if (![fileManager fileExistsAtPath:self.theVideoPath]) {
        self.progresslabel.text = @"文件不存在";
        return;
    }
    
    NSURL *sourceMovieURL = [NSURL fileURLWithPath:self.theVideoPath];
    
    AVAsset *movieAsset = [AVURLAsset URLAssetWithURL:sourceMovieURL options:nil];
    
    AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:movieAsset];
    
    AVPlayer *player = [AVPlayer playerWithPlayerItem:playerItem];
    
    AVPlayerLayer *playerLayer = [AVPlayerLayer playerLayerWithPlayer:player];
    
    playerLayer.frame = CGRectMake(0, 0, WIDTH, HEIGHT);
    
    playerLayer.videoGravity = AVLayerVideoGravityResizeAspect;
    
    [self.view.layer addSublayer:playerLayer];
    
    [player play];
    
}

//保存视频到相册
-(void)saveVideoToAlbumWith:(NSString *)urlStr{
//    if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(urlStr)) {//这里也会执行一次下面的代理方法
        //保存视频相册核心代码
        UISaveVideoAtPathToSavedPhotosAlbum(urlStr, self, @selector(video:didFinishSavingWithError:contextInfo:), nil);
        
//}
}
#pragma mark 视频保存完毕的回调
- (void)video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{
    if (error) {
NSLog(@"保存视频过程中发生错误，错误信息:%@",error.localizedDescription);
    }else{
        NSLog(@"视频保存成功.");
        [self createVideopath];//保存完吧沙盒中的路径清空
    }
}

3.其他视频和图片互转

1、图片转视频流（CVPixelBufferRef）

// image convert to Pixel buffer
- (CVPixelBufferRef)pixelBufferFromCGImage:(CGImageRef)image
                                      size:(CGSize)imageSize
{
    NSDictionary *options = @{(id)kCVPixelBufferCGImageCompatibilityKey: @YES,
                              (id)kCVPixelBufferCGBitmapContextCompatibilityKey: @YES};
    CVPixelBufferRef pxbuffer = NULL;
    CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, imageSize.width,
                                          imageSize.height, kCVPixelFormatType_32ARGB, (__bridge CFDictionaryRef) options,
                                          &pxbuffer);
    NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);

    CVPixelBufferLockBaseAddress(pxbuffer, 0);
    void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
    NSParameterAssert(pxdata != NULL);

    CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(pxdata, imageSize.width,
                                                 imageSize.height, 8, 4*imageSize.width, rgbColorSpace,
                                                 kCGImageAlphaNoneSkipFirst);
    NSParameterAssert(context);

    CGContextDrawImage(context, CGRectMake(0 + (imageSize.width-CGImageGetWidth(image))/2,
                                           (imageSize.height-CGImageGetHeight(image))/2,
                                           CGImageGetWidth(image),
                                           CGImageGetHeight(image)), image);
    CGColorSpaceRelease(rgbColorSpace);
    CGContextRelease(context);

    CVPixelBufferUnlockBaseAddress(pxbuffer, 0);

    return pxbuffer;
}
2、视频流（CVImageBufferRef）转图片

// CVImageBufferRef to UIImage
- (UIImage *)screenshotOfVideoStream:(CVImageBufferRef)imageBuffer
{
    CIImage *ciImage = [CIImage imageWithCVPixelBuffer:imageBuffer];
    CIContext *temporaryContext = [CIContext contextWithOptions:nil];
    CGImageRef videoImage = [temporaryContext
                             createCGImage:ciImage
                             fromRect:CGRectMake(0, 0,
                                                 CVPixelBufferGetWidth(imageBuffer),
                                                 CVPixelBufferGetHeight(imageBuffer))];

    UIImage *image = [[UIImage alloc] initWithCGImage:videoImage];
    CGImageRelease(videoImage);
    return image;
}
3、视频流（CVImageBufferRef）转图片

+ (UIImage *)trasformToImageFromSampleBuffer:(CMSampleBufferRef)sampleBuffer
{
    CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
    
    void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer);
    size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);
    size_t width = CVPixelBufferGetWidth(imageBuffer);
    size_t height = CVPixelBufferGetHeight(imageBuffer);
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(baseAddress, width, height, 8,
                                                 bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
    CGImageRef quartzImage = CGBitmapContextCreateImage(context);
    
    CGContextRelease(context);
    CGColorSpaceRelease(colorSpace);
    UIImage *image = [UIImage imageWithCGImage:quartzImage scale:1.0 orientation:UIImageOrientationRight];
    
    CGImageRelease(quartzImage);
    return (image);
}