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I also have a question regarding ML. Are there resources where I can see how could I treat video sequences (series of images / spatial/temporal continuity) as i

I also have a question regarding ML. Are there resources where I can see how could I treat video sequences (series of images / spatial/temporal continuity) as inputs? Trying to find a starting point for learning and use case I have in mind.

windexh8er 10y ago
I may be off base here but wouldn't CV be part of what you're interested in? If so I've found Adrian Rosebrock has some great paid for and free options: https://www.pyimagesearch.com https://www.pyimagesearch.com (free tutorials in the blog) https://www.pyimagesearch.com/pyimagesearch-gurus/ https://www.pyimagesearch.com/pyimagesearch-gurus/ (paid for "guru" course)
- Keyframe 10y ago
  You're right, computer vision is/would be definitely a part of it. Thanks for the link. Guru seems a bit pricey for a hobby, but maybe I'll go with it.
lgessler 10y ago
There's a really straightforward approach to turning video into feature vectors which you can readily plug into any old ML algorithm. You can turn every decoded frame (which is essentially a PNG, right?) into a (Width*Height)x1 vector, where each cell is an RGB pixel. You can then compose these vectors into a matrix, or perform further operations on them, e.g. SVD. Whether or not this is a good approach, though, will depend of course on your application. For face detection, for example, this is not adequate, and you'll need more sophisticated algorithms. For a good overview of that, see Jason Lawrence's slides[1] and also take a look at some of the other stuff he covered in his Computer Vision course[2]. Sorry if that's too basic for what you were asking. If you want to see some messy code that does this using OpenCV, here's some I wrote a while back with a friend, starting on line 127: https://github.com/sprestwood/CompVisionS2015/blob/master/test_scripts/people_detector.py#L127 https://github.com/sprestwood/CompVisionS2015/blob/master/te... [1] http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/lectures/lecture07_recognition.pdf http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/le... [2] http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/schedule.html http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/sc...
- Keyframe 10y ago
  Thanks for pointers! I'm basically below/at 101 with ML, but have background in computer graphics. I was wondering if one could utilise ML for either or both of two things: object outline spatial/temporal (feathering can solve for motion blur) and better Chroma key.
  - lgessler 10y ago
    For outlining, my initial reaction is to reach for two things: 1. Kalman filters to track an object in motion within a frame [1] 2. Edge detection on the subframe you got from (1) [2] Both appear to be available out of the box in OpenCV[3][4], though you'll have to fiddle with parameters I'm sure. [1] Example: https://www.youtube.com/watch?v=K14SK4v3-IY https://www.youtube.com/watch?v=K14SK4v3-IY [2] https://en.wikipedia.org/wiki/Canny_edge_detector https://en.wikipedia.org/wiki/Canny_edge_detector [3] http://docs.opencv.org/trunk/dd/d6a/classcv_1_1KalmanFilter.html http://docs.opencv.org/trunk/dd/d6a/classcv_1_1KalmanFilter.... [4] http://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/canny_detector/canny_detector.html http://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/ca...

windexh8er 10y ago

I may be off base here but wouldn't CV be part of what you're interested in? If so I've found Adrian Rosebrock has some great paid for and free options: https://www.pyimagesearch.com https://www.pyimagesearch.com (free tutorials in the blog) https://www.pyimagesearch.com/pyimagesearch-gurus/ https://www.pyimagesearch.com/pyimagesearch-gurus/ (paid for "guru" course)

Keyframe 10y ago
You're right, computer vision is/would be definitely a part of it. Thanks for the link. Guru seems a bit pricey for a hobby, but maybe I'll go with it.

lgessler 10y ago

There's a really straightforward approach to turning video into feature vectors which you can readily plug into any old ML algorithm. You can turn every decoded frame (which is essentially a PNG, right?) into a (Width*Height)x1 vector, where each cell is an RGB pixel. You can then compose these vectors into a matrix, or perform further operations on them, e.g. SVD. Whether or not this is a good approach, though, will depend of course on your application. For face detection, for example, this is not adequate, and you'll need more sophisticated algorithms. For a good overview of that, see Jason Lawrence's slides[1] and also take a look at some of the other stuff he covered in his Computer Vision course[2]. Sorry if that's too basic for what you were asking. If you want to see some messy code that does this using OpenCV, here's some I wrote a while back with a friend, starting on line 127: https://github.com/sprestwood/CompVisionS2015/blob/master/test_scripts/people_detector.py#L127 https://github.com/sprestwood/CompVisionS2015/blob/master/te... [1] http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/lectures/lecture07_recognition.pdf http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/le... [2] http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/schedule.html http://www.cs.virginia.edu/~gfx/Courses/2015/TopicsVision/sc...

Keyframe 10y ago
Thanks for pointers! I'm basically below/at 101 with ML, but have background in computer graphics. I was wondering if one could utilise ML for either or both of two things: object outline spatial/temporal (feathering can solve for motion blur) and better Chroma key.
- lgessler 10y ago
  For outlining, my initial reaction is to reach for two things: 1. Kalman filters to track an object in motion within a frame [1] 2. Edge detection on the subframe you got from (1) [2] Both appear to be available out of the box in OpenCV[3][4], though you'll have to fiddle with parameters I'm sure. [1] Example: https://www.youtube.com/watch?v=K14SK4v3-IY https://www.youtube.com/watch?v=K14SK4v3-IY [2] https://en.wikipedia.org/wiki/Canny_edge_detector https://en.wikipedia.org/wiki/Canny_edge_detector [3] http://docs.opencv.org/trunk/dd/d6a/classcv_1_1KalmanFilter.html http://docs.opencv.org/trunk/dd/d6a/classcv_1_1KalmanFilter.... [4] http://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/canny_detector/canny_detector.html http://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/ca...