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Algorithm to detect corners of paper sheet in photo
...ving small objects and or noise, lower the canny restraints, so it accepts more edges, and then find the largest closed contour (in OpenCV use findcontour() with some simple parameters, I think I used CV_RETR_LIST). might still struggle when it's on a white piece of paper, but was definitely providi...
How can I extract a good quality JPEG image from a video file with ffmpeg?
...put.mp4 -qscale:v 2 output_%03d.jpg
See the image muxer documentation for more options involving image outputs.
To output a single image at ~60 seconds duration:
ffmpeg -ss 60 -i input.mp4 -qscale:v 4 -frames:v 1 output.jpg
This will work with any video input. See below if your input is MJPEG.
MJ...
NSOperation vs Grand Central Dispatch
...ng a custom NSOperation or NSInvocationOperation to do this requires a lot more supporting code. I know that you can use an NSBlockOperation, but you might as well be dispatching something to GCD then. Wrapping this code in blocks inline with related processing in your application leads in my opinio...
How to do ToString for a possibly null object?
...ng.Empty).ToString();
or
string s = (myObjc ?? "").ToString()
to be even more concise.
Unfortunately, as has been pointed out you'll often need a cast on either side to make this work with non String or Object types:
string s = (myObjc ?? (Object)"").ToString()
string s = ((Object)myObjc ?? "").To...
“cannot resolve symbol R” in Android Studio
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Grepping a huge file (80GB) any way to speed it up?
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Some people (not me) like grep -F more than fgrep
– Walter Tross
Jun 18 '14 at 9:21
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Is there a predefined enumeration for Month in the .NET library?
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What does the red exclamation point icon in Eclipse mean?
...sons, depending on what plugins are active. Check the "Problems" view for more information.
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Swift compiler segmentation fault when building
...urrentMeal is nil ? it's the same no ? could you explain me why my code is more dangerous than yours please ? swift take advantage of optional without using "?" ?
– Fjohn
Jan 14 '15 at 9:19
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What are bitwise operators?
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Wow, that makes a lot more sense now. It sounded a lot more complicated than it apparently is. Thanks. I'm not sure which to choose as the right answer as there are loads of good ones, and I can't upvote so.. thanks
– click
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