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How to create a video from images with FFmpeg?
...video filter instead of -r for the output framerate
ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
Alternatively the format video filter can be added to the filter chain to replace -pix_fmt yuv420p like "fps=25,format=yuv420p". The advantage of this method is th...
Best way of returning a random boolean value
...alse].sample is faster than rand(2) == 1. When I performed each operation 10 million times the rand method was 2.179s. The sample method was 1.645s.
– Mirror318
Jun 27 '16 at 4:47
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Javascript seconds to minutes and seconds
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To get the number of full minutes, divide the number of total seconds by 60 (60 seconds/minute):
var minutes = Math.floor(time / 60);
And to get the remaining seconds, multiply the full minutes with 60 and subtract from the total seconds:
var seconds = time - minutes * 60;
Now if you also wan...
What does the constant 0.0039215689 represent?
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0.0039215689 is approximately equal to 1/255.
Seeing that this is OpenGL, performance is probably important. So it's probably safe to guess that this was done for performance reasons.
Multiplying by the reciprocal is faster...
What is the Ruby (spaceship) operator?
...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument.
a <=> b :=
if a < b t...
ValueError: math domain error
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edited Sep 3 '17 at 20:49
answered Apr 8 '13 at 23:06
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How to remove leading zeros from alphanumeric text?
...s leading zeroes, but leaves one if necessary (i.e. it wouldn't just turn "0" to a blank string).
s.replaceFirst("^0+(?!$)", "")
The ^ anchor will make sure that the 0+ being matched is at the beginning of the input. The (?!$) negative lookahead ensures that not the entire string will be matched....
Is SQL or even TSQL Turing Complete?
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Qantas 94 Heavy
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answered Sep 28 '11 at 7:59
Jan de VosJan de Vos
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Warning: Found conflicts between different versions of the same dependent assembly
I am currently developing a .NET application, which consists of 20 projects. Some of those projects are compiled using .NET 3.5, some others are still .NET 2.0 projects (so far no problem).
...
C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
...t. Many thanks to him - and please visit his blog, which rocks.
The value 0 here is only special because it's not a valid state which you might be in just before the await in a normal case. In particular, it's not a state which the state machine may end up testing for elsewhere. I believe that usin...