Convert incoming NSStream to View

问题

I'm successfully sending a stream of NSData. The delegate method below is getting that stream and appending to NSMutableData self.data. How do I take this data and make it into a UIView/AVCaptureVideoPreviewLayer (which should show video)? I feel like I'm missing another conversion, AVCaptureSession > NSStream > MCSession > NSStream > ?

- (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)eventCode {
    switch(eventCode) {
        case NSStreamEventHasBytesAvailable:
        {
            if(!self.data) {
                self.data = [NSMutableData data];
            }
            uint8_t buf[1024];
            unsigned int len = 0;
            len = [(NSInputStream *)stream read:buf maxLength:1024];
            if(len) {
                [self.data appendBytes:(const void *)buf length:len];
            } else {
                NSLog(@"no buffer!");
            }

// Code here to take self.data and convert the NSData to UIView/Video
}

I send the stream with this:

-(void) captureOutput:(AVCaptureOutput*)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection*)connection
{

    CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
    CVPixelBufferLockBaseAddress(imageBuffer,0);

    size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);
//    size_t width = CVPixelBufferGetWidth(imageBuffer);
    size_t height = CVPixelBufferGetHeight(imageBuffer);
    void *src_buff = CVPixelBufferGetBaseAddress(imageBuffer);

    NSData *data = [NSData dataWithBytes:src_buff length:bytesPerRow * height];

    CVPixelBufferUnlockBaseAddress(imageBuffer, 0);


    NSError *error;
    self.oStream = [self.mySession startStreamWithName:@"videoOut" toPeer:[[self.mySession connectedPeers]objectAtIndex:0] error:&error];
    self.oStream.delegate = self;
    [self.oStream scheduleInRunLoop:[NSRunLoop mainRunLoop]
                            forMode:NSDefaultRunLoopMode];
    [self.oStream open];

    [self.oStream write:[data bytes] maxLength:[data length]];






//    CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer( sampleBuffer );

    CGSize imageSize = CVImageBufferGetEncodedSize( imageBuffer );
    // also in the 'mediaSpecific' dict of the sampleBuffer

    NSLog( @"frame captured at %.fx%.f", imageSize.width, imageSize.height );
}

回答1:

I think you need AVCaptureManager, see if the code below works for you..

AVCamCaptureManager *manager = [[AVCamCaptureManager alloc] init];
[self setCaptureManager:manager];

[[self captureManager] setDelegate:self];

if ([[self captureManager] setupSession]) {
     // Create video preview layer and add it to the UI
    AVCaptureVideoPreviewLayer *newCaptureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:[[self captureManager] session]];
    UIView *view = self.videoPreviewView;//Add a view in XIB where you want to show video
    CALayer *viewLayer = [view layer];
    [viewLayer setMasksToBounds:YES];
    CGRect bounds = [view bounds];

    [newCaptureVideoPreviewLayer setFrame:bounds];

    [newCaptureVideoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];

    [viewLayer insertSublayer:newCaptureVideoPreviewLayer below:[[viewLayer sublayers] objectAtIndex:0]];

    [self setCaptureVideoPreviewLayer:newCaptureVideoPreviewLayer];

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        [[[self captureManager] session] startRunning];
    });
}

Manage the delegates

- (void)captureManager:(AVCamCaptureManager *)captureManager didFailWithError:(NSError *)error
{

}

- (void)captureManagerRecordingBegan:(AVCamCaptureManager *)captureManager
{

}

- (void)captureManagerRecordingFinished:(AVCamCaptureManager *)captureManager outputURL:(NSURL *)url
{



}

- (void)captureManagerStillImageCaptured:(AVCamCaptureManager *)captureManager
{



}

- (void)captureManagerDeviceConfigurationChanged:(AVCamCaptureManager *)captureManager
{

}

I hope it helps.

回答2:

You can make an UIImageView on yout handle event like this:

UIImageView * iv = [[UIImageView alloc] initWithImage: [UIImage imageWithData: self.data];

Also you can alloc just once and just call init.

Each time u receive from socket, you initialize the UIImageView and you can show it adding that UIImageView to a UIView.

Sorry for my english, I don´t know if I have understood you

来源：https://stackoverflow.com/questions/22390679/convert-incoming-nsstream-to-view