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2015-12-22 12:11:54 -0500 commented question best resolution for negatives on traincascade?

So this isn't unexpectedly slow?

2015-12-22 09:12:20 -0500 asked a question best resolution for negatives on traincascade?

I'm training a cascade classifier now and it's on the 6th stage and has been there for more than 48 hours so far. It's slowly working through the negatives. I'm wondering if the resolution of the negatives is causing this? They are large-ish images (roughly desktop background resolution). I noticed that using cascade classifiers is much faster with smaller images so I can only imagine that training with large images slows it down as well. Any experience with this?

So what is the ideal resolution for negatives?

2015-12-20 14:03:30 -0500 answered a question opencv_traincascade throwing error "...lbpfeatures.cpp:17: error: (-215) _maxSampleCount > 0 in function init"

I'm not sure what the original cause for this error was but ultimately I recreated the negatives.txt file using full file paths and also did not use -featureType switch.

2015-12-13 10:57:17 -0500 answered a question Unable to open mp4 video file with VideoCapture before and after recompiling with ffmpeg

I think you have to have mp4 codec installed in your OS. Make sure your environment can open/understand MP4 before OpenCV can understand it.

2015-12-13 10:52:05 -0500 received badge  Supporter (source)
2015-12-13 10:31:46 -0500 asked a question opencv_traincascade throwing error "...lbpfeatures.cpp:17: error: (-215) _maxSampleCount > 0 in function init"

Hello everyone. An internet search suggested that this was a bug that was patched in the past so I have no idea what I'm doing wrong to recreate this bug. I've tried it in 2.4.11 and 3.0.0. Running on Linux Mint 17.2 64-bit.

Here's the full command and output:

[email protected] ~/file/path $ opencv_traincascade -data ~/file/path/ -vec cards.vec -bg negatives.txt -numPos 500 -numNeg -500 -numStages 2 -w 53 -h 74 -featureType LBP
OpenCV Error: Assertion failed (_maxSampleCount > 0) in init, file /home/user/Documents/opencv-3.0.0/apps/traincascade/lbpfeatures.cpp, line 17
terminate called after throwing an instance of 'cv::Exception'
  what():  /home/user/Documents/opencv-3.0.0/apps/traincascade/lbpfeatures.cpp:17: error: (-215) _maxSampleCount > 0 in function init


I have 790 positive samples to use and 40,000 negative samples so I know I'm not running out. What could cause this? Is it possibly a bug in my negatives.txt? I've followed several different guides/tutorials from the internet, all to no avail.