Selectable Video Input

adamfenn28's picture

Needing to be able to specify the capture device on the Video Input patch from a published input, I set out looking for something to provide that. I found a patch that does exactly that, but only for video media types (not muxed video types). I need to support both, so I made a few changes and thought I pretty much had it taken care of... but I didn't. For muxed media types (coming in from my Canopus ADVC-110), when I test the CVImageBufferGetColorSpace() of my imageBuffer, it is (null). I've looked at this and the QTKit documentation and I just doing see what I'm missing. What else do I need to do?

Thanks!

#import <OpenGL/CGLMacro.h>
#import "CaptureWithDevice.h"
 
#define   kQCPlugIn_Name            @"Capture With Device"
#define   kQCPlugIn_Description      @"Servies as a replacement for the default Video Input patch, and differs in that it allows the input device to be specified by the user."
 
@implementation CaptureWithDevice
@dynamic inputDevice, outputImage;
 
+ (NSDictionary*) attributes
{
   return [NSDictionary dictionaryWithObjectsAndKeys:
         kQCPlugIn_Name, QCPlugInAttributeNameKey, 
         kQCPlugIn_Description, QCPlugInAttributeDescriptionKey,
         nil];
}
+ (NSDictionary*) attributesForPropertyPortWithKey:(NSString*)key
{      
   if([key isEqualToString:@"inputDevice"]) {
        NSArray *videoDevices= [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo];
      NSArray *muxedDevices= [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeMuxed];
 
        NSMutableArray *mutableArrayOfDevice = [[NSMutableArray alloc] init ];
        [mutableArrayOfDevice addObjectsFromArray:videoDevices];
        [mutableArrayOfDevice addObjectsFromArray:muxedDevices];
 
        NSArray *devices = [NSArray arrayWithArray:mutableArrayOfDevice];
        [mutableArrayOfDevice release];
 
        NSMutableArray *deviceNames= [NSMutableArray array];
 
        int i, ic= [devices count];
 
 
        for(i= 0; i<ic; i++) {
         [deviceNames addObject:[ [devices objectAtIndex:i] description] ];
            // be sure not to add CT to the list
      }
 
 
 
      return [NSDictionary dictionaryWithObjectsAndKeys:
            @"Device", QCPortAttributeNameKey,
            QCPortTypeIndex,QCPortAttributeTypeKey,
            [NSNumber numberWithInt:0], QCPortAttributeMinimumValueKey,
            deviceNames, QCPortAttributeMenuItemsKey,
            [NSNumber numberWithInt:ic-1], QCPortAttributeMaximumValueKey,
            nil];
   }
   if([key isEqualToString:@"outputImage"])
      return [NSDictionary dictionaryWithObjectsAndKeys:
            @"Video Image", QCPortAttributeNameKey,
            nil];
   return nil;
}
+ (QCPlugInExecutionMode) executionMode
{
   return kQCPlugInExecutionModeProvider;
}
 
+ (QCPlugInTimeMode) timeMode
{
   return kQCPlugInTimeModeIdle;
}
 
- (id) init
{
   if(self = [super init]) {
      [[NSNotificationCenter defaultCenter] addObserver:self 
                                     selector:@selector(_devicesDidChange:) 
                                        name:QTCaptureDeviceWasConnectedNotification 
                                       object:nil];
      [[NSNotificationCenter defaultCenter] addObserver:self 
                                     selector:@selector(_devicesDidChange:) 
                                        name:QTCaptureDeviceWasDisconnectedNotification 
                                       object:nil];
   }
   return self;
}
 
- (void) finalize
{
   [super finalize];
}
 
- (void) dealloc
{
   if (mCaptureSession) {
      [mCaptureSession release];
      [mCaptureDeviceInput release];
      [mCaptureDecompressedVideoOutput release];
   }
   [[NSNotificationCenter defaultCenter] removeObserver:self];
   [super dealloc];
}
 
@end
 
@implementation CaptureWithDevice (Execution)
 
- (BOOL) startExecution:(id<QCPlugInContext>)context
{
   return YES;
}
 
- (void) enableExecution:(id<QCPlugInContext>)context
{
}
static void _BufferReleaseCallback(const void* address, void* info)
{
    CVPixelBufferUnlockBaseAddress(info, 0); 
 
    CVBufferRelease(info);
}
- (BOOL) execute:(id<QCPlugInContext>)context atTime:(NSTimeInterval)time withArguments:(NSDictionary*)arguments
{
   if (!mCaptureSession || [mCaptureSession isRunning]==NO || _currentDevice!=self.inputDevice){
      NSError *error = nil;
      BOOL success;
 
      NSArray *videoDevices= [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo];
      NSArray *muxedDevices= [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeMuxed];
 
        NSMutableArray *mutableArrayOfDevice = [[NSMutableArray alloc] init ];
        [mutableArrayOfDevice addObjectsFromArray:videoDevices];
        [mutableArrayOfDevice addObjectsFromArray:muxedDevices];
 
        NSArray *devices = [NSArray arrayWithArray:mutableArrayOfDevice];
        [mutableArrayOfDevice release];
 
 
      NSUInteger d= self.inputDevice;
      if (!(d<[devices count])) {
         d= 0;
      }
      QTCaptureDevice *device = [devices objectAtIndex:d];
        success = [device open:&error];
        if (!success) {
            NSLog(@"Could not open device %@", device);
         self.outputImage = nil; 
            return YES;
        } 
        NSLog(@"Opened device successfully");
 
 
 
 
      [mCaptureSession release];
        mCaptureSession = [[QTCaptureSession alloc] init];
 
        [mCaptureDeviceInput release];
        mCaptureDeviceInput = [[QTCaptureDeviceInput alloc] initWithDevice:device];
 
        // if the device is a muxed connection  make sure to get the right connection
        if ([muxedDevices containsObject:device]) {
            NSLog(@"Disabling audio connections");
            NSArray *ownedConnections = [mCaptureDeviceInput connections];
            for (QTCaptureConnection *connection in ownedConnections) {
                NSLog(@"MediaType: %@", [connection mediaType]);
                if ( [[connection mediaType] isEqualToString:QTMediaTypeSound]) {
                    [connection setEnabled:NO];
                    NSLog(@"disabling audio connection");
 
                }
            }
        }
 
 
 
        success = [mCaptureSession addInput:mCaptureDeviceInput error:&error];
 
        if (!success) {
            NSLog(@"Failed to add Input");
         self.outputImage = nil; 
            if (mCaptureSession) {
                [mCaptureSession release];
                mCaptureSession= nil;
            }
            if (mCaptureDeviceInput) {
                [mCaptureDeviceInput release];
                mCaptureDeviceInput= nil;
 
            }
            return YES;
        }
 
 
 
 
        NSLog(@"Adding output");
 
        [mCaptureDecompressedVideoOutput release];
        mCaptureDecompressedVideoOutput = [[QTCaptureDecompressedVideoOutput alloc] init];
 
        [mCaptureDecompressedVideoOutput setPixelBufferAttributes:
         [NSDictionary dictionaryWithObjectsAndKeys:
          [NSNumber numberWithBool:YES], kCVPixelBufferOpenGLCompatibilityKey,
          [NSNumber numberWithLong:k32ARGBPixelFormat], kCVPixelBufferPixelFormatTypeKey, nil]];
 
        [mCaptureDecompressedVideoOutput setDelegate:self];
        success = [mCaptureSession addOutput:mCaptureDecompressedVideoOutput error:&error];
 
        if (!success) {
            NSLog(@"Failed to add output");
         self.outputImage = nil; 
            if (mCaptureSession) {
                [mCaptureSession release];
                mCaptureSession= nil;
            }
            if (mCaptureDeviceInput) {
                [mCaptureDeviceInput release];
                mCaptureDeviceInput= nil;
            }
            if (mCaptureDecompressedVideoOutput) {
                [mCaptureDecompressedVideoOutput release];
                mCaptureDecompressedVideoOutput= nil;
            }
            return YES;
        }
 
        [mCaptureSession startRunning];   
      _currentDevice= self.inputDevice;
   }
 
 
   CVImageBufferRef imageBuffer = CVBufferRetain(mCurrentImageBuffer);
 
    if (imageBuffer) {
        CVPixelBufferLockBaseAddress(imageBuffer, 0);
        NSLog(@"ColorSpace: %@", CVImageBufferGetColorSpace(imageBuffer));
        //NSLog(@"ColorSpace: %@ Height: %@ Width: %@", CVImageBufferGetColorSpace(imageBuffer), CVPixelBufferGetWidth(imageBuffer), CVPixelBufferGetHeight(imageBuffer));
        id provider= [context outputImageProviderFromBufferWithPixelFormat:QCPlugInPixelFormatARGB8           
                                                                pixelsWide:CVPixelBufferGetWidth(imageBuffer)
                                                                pixelsHigh:CVPixelBufferGetHeight(imageBuffer)
                                                               baseAddress:CVPixelBufferGetBaseAddress(imageBuffer)
                                                               bytesPerRow:CVPixelBufferGetBytesPerRow(imageBuffer)
                                                           releaseCallback:_BufferReleaseCallback
                                                            releaseContext:imageBuffer
                                                                colorSpace:CVImageBufferGetColorSpace(imageBuffer)
                                                          shouldColorMatch:YES];
      if(provider == nil) {
         return NO; 
        }
      self.outputImage = provider;
    } 
   else 
      self.outputImage = nil; 
 
   return YES; 
}
 
- (void) disableExecution:(id<QCPlugInContext>)context
{
}
- (void) stopExecution:(id<QCPlugInContext>)context
{
}
 
- (void)captureOutput:(QTCaptureOutput *)captureOutput
  didOutputVideoFrame:(CVImageBufferRef)videoFrame 
    withSampleBuffer:(QTSampleBuffer *)sampleBuffer 
      fromConnection:(QTCaptureConnection *)connection
{    
    NSLog(@"connection type: %@", [connection mediaType]);
    CVImageBufferRef imageBufferToRelease;
    CVBufferRetain(videoFrame);
    imageBufferToRelease = mCurrentImageBuffer;
 
 
    @synchronized (self) {
        mCurrentImageBuffer = videoFrame;
    }
    CVBufferRelease(imageBufferToRelease);
}
- (void)_devicesDidChange:(NSNotification *)aNotification
{
}
@end

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adamfenn28's picture
Re: Selectable Video Input

I suspect my problem is in this statement:

       [mCaptureDecompressedVideoOutput setPixelBufferAttributes:
         [NSDictionary dictionaryWithObjectsAndKeys:
          [NSNumber numberWithBool:YES], kCVPixelBufferOpenGLCompatibilityKey,
          [NSNumber numberWithLong:k32ARGBPixelFormat], kCVPixelBufferPixelFormatTypeKey, nil]];

This works well with the FaceTime HD input, an another QTMediaTypeVideo device (the UltraStudio 3D), the plugin crashes when I try to selected a FireWire input. There must be something I'm missing about handling QTMediaTypeMuxed devices. Can anyone point it out?

Thanks!

ahoeben's picture
Re: Selectable Video Input

Adam, thanks so much for your code. I am working on a "forked" version of here: https://github.com/fieldOfView/QTKitCapture

The functionality I am adding is a settable Width & Height that is passed to QTKit. The upshot of this is that for webcams which have high resolution/low framerate modes, you can now chose to get a lower resolution, higher framerate feed instead of the default, which is often unusably slow. For example the default Video Input patch when used with a Logitech HD Pro Webcam C920 results in a stream of 2 megapixel images at ~2 fps, while with my version of your code it will also do 720p at 30 fps.

It is very much a work in progress, so any c&c is welcome. And I did not fix your muxed device problem.