直播视频app源码，获取视频缩略图相关的代码

缩略图
AVAeest AVPlayer
 
NSMutableDictionary * headers = [NSMutableDictionary dictionary]; [headers setObject:@"yourHeader"forKey:@"User-Agent"]; self.urlAsset = [AVURLAsset URLAssetWithURL:self.videoURL options:@{@"AVURLAssetHTTPHeaderFieldsKey" : headers}];  self.playerItem = [AVPlayerItem playerItemWithAsset:self.urlAsset];
 
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:[NSURL fileURLWithPath:model.localPath] options:nil];
AVAssetImageGenerator *gen = [[AVAssetImageGenerator alloc] initWithAsset:asset];
gen.appliesPreferredTrackTransform = YES;
CMTime time = CMTimeMakeWithSeconds(0.1, 600);
NSError *error = nil;
CMTime actualTime;
CGImageRef image = [gen copyCGImageAtTime:time actualTime:&actualTime error:&error];
UIImage *thumb = [[UIImage alloc] initWithCGImage:image];
 
 
 
- (UIImage *)generatorImageVideoPath:(NSString *)videoPath
{
    AVAsset *videoAsset = [AVAsset assetWithURL:[NSURL fileURLWithPath:videoPath]];
    AVAssetImageGenerator *generator = [[AVAssetImageGenerator alloc] initWithAsset:videoAsset];
NSError *error = nil;  
CMTime actualTime;  
CGImageRef imageRef = [generator copyCGImageAtTime:CMTimeMakeWithSeconds(0.1, videoAsset.duration.timescale)  actualTime:&actualTime error:&error];
    UIImage *thumbnail = [UIImage imageWithCGImage:imageRef];
    CGImageRelease(imageRef);
    
    return thumbnail;
}
 
 
+ (UIImage*) thumbnailImageForVideo :( NSURL *)videoURL atTime :( NSTimeInterval)time {
    AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];
    NSParameterAssert(asset);
    AVAssetImageGenerator *assetImageGenerator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
    assetImageGenerator.appliesPreferredTrackTransform = YES;
    assetImageGenerator.apertureMode = AVAssetImageGeneratorApertureModeEncodedPixels;
    
    CGImageRef thumbnailImageRef = NULL;
    CFTimeInterval thumbnailImageTime = time;
    NSError *thumbnailImageGenerationError = nil;
    thumbnailImageRef = [assetImageGenerator copyCGImageAtTime:CMTimeMake(thumbnailImageTime, 60) actualTime:NULL error:&thumbnailImageGenerationError];
    
    if (!thumbnailImageRef)
        NSLog(@"thumbnailImageGenerationError %@", thumbnailImageGenerationError);
    
    UIImage *thumbnailImage = thumbnailImageRef ? [[UIImage alloc] initWithCGImage:thumbnailImageRef] : nil;
    
    return thumbnailImage;
}
 
 
 
-(void)encodeVideo
{
    path = [[NSBundle mainBundle] pathForResource:@"sd" ofType:@"MP4"];
    NSLog(@"=%@\n\n%@",NSHomeDirectory(),path);
    
    NSArray *path2 = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsPath = [path2 objectAtIndex:0];
    bakPath =[documentsPath stringByAppendingPathComponent:@"aaa.MP4"];
    AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:[NSURL fileURLWithPath:path] options:nil];
    
    AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:avAsset presetName:AVAssetExportPresetLowQuality];
    exportSession.outputURL = [NSURL fileURLWithPath:bakPath];
    exportSession.outputFileType = AVFileTypeMPEG4;
    exportSession.shouldOptimizeForNetworkUse= YES;
    [exportSession exportAsynchronouslyWithCompletionHandler:^(void)
     {
         switch (exportSession.status) {
             case AVAssetExportSessionStatusCancelled:
                 NSLog(@"AVAssetExportSessionStatusCancelled");
                 break;
             case AVAssetExportSessionStatusUnknown:
                 NSLog(@"AVAssetExportSessionStatusUnknown");
                 break;
             case AVAssetExportSessionStatusWaiting:
                 NSLog(@"AVAssetExportSessionStatusWaiting");
                 break;
             case AVAssetExportSessionStatusExporting:
                 NSLog(@"AVAssetExportSessionStatusExporting");
                 break;
             case AVAssetExportSessionStatusCompleted:
                 
                 path=bakPath;
                 //压缩成功
                 NSLog(@"Success");
                 break;
             case AVAssetExportSessionStatusFailed:
             {
                 NSError *error=exportSession.error;
                 if (error) {
                     
                 }
                 NSLog(@"AVAssetExportSessionStatusFailed");
             }
                 
                 break;
             default:
                 
                 break;
         }
         
     }];
}
 
/**
 *  把视频文件拆成图片保存在沙盒中
 *
 *  @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
 */
- (void)splitVideo:(NSURL *)fileUrl fps:(float)fps completedBlock:(void(^)(void))completedBlock {
    if (!fileUrl) {
        return;
    }
    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
    totalNumber = (int)totalFrames;
    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];
    }
    
    NSLog(@"------- start");
    AVAssetImageGenerator *imgGenerator = [[AVAssetImageGenerator alloc] initWithAsset:avasset];
    //防止时间出现偏差
    imgGenerator.requestedTimeToleranceBefore = kCMTimeZero;
    imgGenerator.requestedTimeToleranceAfter = kCMTimeZero;
    NSString *cachePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
    NSInteger timesCount = [times count];
    [imgGenerator generateCGImagesAsynchronouslyForTimes:times completionHandler:^(CMTime requestedTime, CGImageRef  _Nullable image, CMTime actualTime, AVAssetImageGeneratorResult result, NSError * _Nullable error) {
        printf("current-----: %lld\n", requestedTime.value);
        switch (result) {
            case AVAssetImageGeneratorCancelled:
                NSLog(@"Cancelled");
                break;
            case AVAssetImageGeneratorFailed:
                NSLog(@"Failed");
                break;
            case AVAssetImageGeneratorSucceeded: {
                NSString *filePath = [cachePath stringByAppendingPathComponent:[NSString stringWithFormat:@"/%lld.png",requestedTime.value]];
                NSData *imgData = UIImagePNGRepresentation([UIImage imageWithCGImage:image]);
                [imgData writeToFile:filePath atomically:YES];
                if (requestedTime.value == timesCount) {
                    NSLog(@"completed");
                    if (completedBlock) {
                        completedBlock();
                    }
                }
            }
                break;
        }
    }];
}

以上就是直播视频app源码，获取视频缩略图相关的代码， 更多内容欢迎关注之后的文章