ios - 如何将视频从 iOS 设备发送到服务器？

Question

我必须将视频从 iPhone 实时发送到服务器。我创建捕获 session 并使用 AVCaptureMovieFileOutput。

NSError *error = nil;

captureSession = [[AVCaptureSession alloc] init];
//查找、附加设备
AVCaptureDevice *muxedDevice = [AVCaptureDevice defaultDeviceWithMediaType: AVMediaTypeMuxed];
如果(多路复用设备){
    NSLog (@"得到 muxedDevice");
    AVCaptureDeviceInput *muxedInput = [AVCaptureDeviceInput deviceInputWithDevice:muxedDevice
                                                                             错误:&error];
    如果(多路输入){
        [captureSession addInput:muxedInput];
    }
} 别的 {
    AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType: AVMediaTypeVideo];
    如果(视频设备){
        NSLog(@"得到视频设备");
        AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice
                                                                                 错误:&error];
        如果(视频输入){
            [捕获 session 添加输入:视频输入]；
        }
    }
    AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType: AVMediaTypeAudio];
    如果(音频设备){
        NSLog(@"获取音频设备");
        AVCaptureDeviceInput *audioInput = [AVCaptureDeviceInput deviceInputWithDevice:audioDevice
                                                                                 错误:&error];
        如果(音频输入){
            [captureSession addInput: audioInput];
        }
    }
}

//从 session 中创建一个预览层并将其添加到 UI
AVCaptureVideoPreviewLayer *previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:captureSession];
previewLayer.frame = view.layer.bounds;
previewLayer.videoGravity = AVLayerVideoGravityResizeAspect;
previewLayer.orientation = AVCaptureVideoOrientationPortrait;
[view.layer addSublayer:previewLayer];

//创建捕获文件输出

captureMovieOutput = [[AVCaptureMovieFileOutput 分配] 初始化];
如果(!captureMovieURL){
    captureMoviePath = [[self getMoviePathWithName:MOVIE_FILE_NAME] 保留];
    captureMovieURL = [[NSURL alloc] initFileURLWithPath:captureMoviePath];
}
NSLog (@"录制到 %@", captureMovieURL);
[captureSession addOutput:captureMovieOutput];

我使用 AVAssetExportSession 获取时长为 10 秒的视频。

     AVURLAsset *asset = [AVURLAsset URLAssetWithURL:captureMovieURL options:[NSDictionary  dictionaryWithObject:@"YES" forKey:AVURLAssetPreferPreciseDurationAndTimingKey]];<p></p>

<pre><code>AVMutableComposition *composition = [AVMutableComposition composition];

CMTime endTime;
CMTime duration = CMTimeMake(6000, 600);
if (asset.duration.value - startFragment.value < 6000)
{
    endTime = asset.duration;
}
else
{
    endTime = CMTimeMake(startFragment.value + 6000, 600);        
}
CMTimeRange editRange = CMTimeRangeMake(startFragment, duration);
startFragment = CMTimeMake(endTime.value, 600);
  NSError *editError = nil;
// and add into your composition 
</code></pre>

<p>[composition insertTimeRange:editRange ofAsset:asset atTime:composition.duration error:&editError];</p>

<code> AVAssetExportSession *exportSession = [AVAssetExportSession exportSessionWithAsset:composition presetName:AVAssetExportPresetPassthrough];

exportSession.shouldOptimizeForNetworkUse = YES;
NSString *name = [NSString stringWithFormat:MOVUE_SEGMENT_NAME, countMovies];
NSString *path = [NSString stringWithFormat:@"file://localhost%@", [self getMoviePathWithName:name]];
NSURL *url = [NSURL URLWithString:path];
NSLog(@"urlsegment = %@", url);
exportSession.outputFileType = AVFileTypeMPEG4;
exportSession.outputURL = url;
[exportSession exportAsynchronouslyWithCompletionHandler:^{

    if (AVAssetExportSessionStatusCompleted == exportSession.status) 
    {
        countMovies++;

        NSLog(@"AVAssetExportSessionStatusCompleted");

    } 
    else if (AVAssetExportSessionStatusFailed == exportSession.status) 
    {                    
         NSLog(@"AVAssetExportSessionStatusFailed: %@", [exportSession.error localizedDescription]);

    } 
    else 
    {
        NSLog(@"Export Session Status: %d", exportSession.status);
    }
}];  
</code>





如果导出 session 状态已完成，我会将视频发送到服务器。但它很慢。要获取持续时间为 10 秒的电影，然后将其发送到服务器需要 15 秒。如果影片的长度小于 10 秒，则什么都不会改变。我怎么解决这个问题？做这个的最好方式是什么？我怎么解决这个问题？在服务器上流式传输视频有什么更好的用途？

Answer 1

使用ffmpeg编码元数据，它可能比AVAssetExportSession更好。但是ffmpeg编码比AVAssetExportSession困难得多；