how can I extract only one frame per second from the CMSampleBuffer for further live processing
I have a live image processing function using openCV that requires processing time, so with the 15 or 30 frames per second my app crashes or get's stuck. I managed to get the thing working by reducing the frames per second with this code:
device.activeVideoMinFrameDuration = CMTimeMake(1, 5)
However, the video output is now very faltering. I'd rather keep the video output at 15 frames per second and extract only lets say every third frame for the live processing (which is an overlay to the video output - it shows a contour). How can I do this? Here is the current code:
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!,
from connection: AVCaptureConnection!) {
imageFromBuffer = CameraUtil.imageFromSampleBuffer(buffer: sampleBuffer)
//// I have a number of openCV image processing functions
//// here in order to be able to show the live contour overlay to the camera output.
}
The way I get the images from the CMSampleBuffer :
class CameraUtil {
class func imageFromSampleBuffer(buffer: CMSampleBuffer) -> UIImage {
let pixelBuffer: CVImageBuffer = CMSampleBufferGetImageBuffer(buffer)!
let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
let pixelBufferWidth = CGFloat(CVPixelBufferGetWidth(pixelBuffer))
let pixelBufferHeight = CGFloat(CVPixelBufferGetHeight(pixelBuffer))
//// set size of output window /////////
let imageRect: CGRect = CGRectMake(0, 0, pixelBufferWidth, pixelBufferHeight/2) ///change camera output display window
let ciContext = CIContext.init()
let cgimage = ciContext.createCGImage(ciImage, from: imageRect )
let image = UIImage(cgImage: cgimage!)
return image
}
class func CGRectMake(_ x: CGFloat, _ y: CGFloat, _ width: CGFloat, _ height: CGFloat) -> CGRect {
return CGRect(x: x, y: y, width: width, height: height)
}
}
swift cmsamplebuffer
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
add a comment |
I have a live image processing function using openCV that requires processing time, so with the 15 or 30 frames per second my app crashes or get's stuck. I managed to get the thing working by reducing the frames per second with this code:
device.activeVideoMinFrameDuration = CMTimeMake(1, 5)
However, the video output is now very faltering. I'd rather keep the video output at 15 frames per second and extract only lets say every third frame for the live processing (which is an overlay to the video output - it shows a contour). How can I do this? Here is the current code:
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!,
from connection: AVCaptureConnection!) {
imageFromBuffer = CameraUtil.imageFromSampleBuffer(buffer: sampleBuffer)
//// I have a number of openCV image processing functions
//// here in order to be able to show the live contour overlay to the camera output.
}
The way I get the images from the CMSampleBuffer :
class CameraUtil {
class func imageFromSampleBuffer(buffer: CMSampleBuffer) -> UIImage {
let pixelBuffer: CVImageBuffer = CMSampleBufferGetImageBuffer(buffer)!
let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
let pixelBufferWidth = CGFloat(CVPixelBufferGetWidth(pixelBuffer))
let pixelBufferHeight = CGFloat(CVPixelBufferGetHeight(pixelBuffer))
//// set size of output window /////////
let imageRect: CGRect = CGRectMake(0, 0, pixelBufferWidth, pixelBufferHeight/2) ///change camera output display window
let ciContext = CIContext.init()
let cgimage = ciContext.createCGImage(ciImage, from: imageRect )
let image = UIImage(cgImage: cgimage!)
return image
}
class func CGRectMake(_ x: CGFloat, _ y: CGFloat, _ width: CGFloat, _ height: CGFloat) -> CGRect {
return CGRect(x: x, y: y, width: width, height: height)
}
}
swift cmsamplebuffer
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
add a comment |
I have a live image processing function using openCV that requires processing time, so with the 15 or 30 frames per second my app crashes or get's stuck. I managed to get the thing working by reducing the frames per second with this code:
device.activeVideoMinFrameDuration = CMTimeMake(1, 5)
However, the video output is now very faltering. I'd rather keep the video output at 15 frames per second and extract only lets say every third frame for the live processing (which is an overlay to the video output - it shows a contour). How can I do this? Here is the current code:
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!,
from connection: AVCaptureConnection!) {
imageFromBuffer = CameraUtil.imageFromSampleBuffer(buffer: sampleBuffer)
//// I have a number of openCV image processing functions
//// here in order to be able to show the live contour overlay to the camera output.
}
The way I get the images from the CMSampleBuffer :
class CameraUtil {
class func imageFromSampleBuffer(buffer: CMSampleBuffer) -> UIImage {
let pixelBuffer: CVImageBuffer = CMSampleBufferGetImageBuffer(buffer)!
let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
let pixelBufferWidth = CGFloat(CVPixelBufferGetWidth(pixelBuffer))
let pixelBufferHeight = CGFloat(CVPixelBufferGetHeight(pixelBuffer))
//// set size of output window /////////
let imageRect: CGRect = CGRectMake(0, 0, pixelBufferWidth, pixelBufferHeight/2) ///change camera output display window
let ciContext = CIContext.init()
let cgimage = ciContext.createCGImage(ciImage, from: imageRect )
let image = UIImage(cgImage: cgimage!)
return image
}
class func CGRectMake(_ x: CGFloat, _ y: CGFloat, _ width: CGFloat, _ height: CGFloat) -> CGRect {
return CGRect(x: x, y: y, width: width, height: height)
}
}
swift cmsamplebuffer
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
I have a live image processing function using openCV that requires processing time, so with the 15 or 30 frames per second my app crashes or get's stuck. I managed to get the thing working by reducing the frames per second with this code:
device.activeVideoMinFrameDuration = CMTimeMake(1, 5)
However, the video output is now very faltering. I'd rather keep the video output at 15 frames per second and extract only lets say every third frame for the live processing (which is an overlay to the video output - it shows a contour). How can I do this? Here is the current code:
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!,
from connection: AVCaptureConnection!) {
imageFromBuffer = CameraUtil.imageFromSampleBuffer(buffer: sampleBuffer)
//// I have a number of openCV image processing functions
//// here in order to be able to show the live contour overlay to the camera output.
}
The way I get the images from the CMSampleBuffer :
class CameraUtil {
class func imageFromSampleBuffer(buffer: CMSampleBuffer) -> UIImage {
let pixelBuffer: CVImageBuffer = CMSampleBufferGetImageBuffer(buffer)!
let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
let pixelBufferWidth = CGFloat(CVPixelBufferGetWidth(pixelBuffer))
let pixelBufferHeight = CGFloat(CVPixelBufferGetHeight(pixelBuffer))
//// set size of output window /////////
let imageRect: CGRect = CGRectMake(0, 0, pixelBufferWidth, pixelBufferHeight/2) ///change camera output display window
let ciContext = CIContext.init()
let cgimage = ciContext.createCGImage(ciImage, from: imageRect )
let image = UIImage(cgImage: cgimage!)
return image
}
class func CGRectMake(_ x: CGFloat, _ y: CGFloat, _ width: CGFloat, _ height: CGFloat) -> CGRect {
return CGRect(x: x, y: y, width: width, height: height)
}
}
swift cmsamplebuffer
swift cmsamplebuffer
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
asked Nov 26 '18 at 5:26
kangarooChriskangarooChris
203314
203314
add a comment |
add a comment |
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