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How can I extract a good quality JPEG image from a video file with ffmpeg?
...le:v (or the alias -q:v) as an output option.
Normal range for JPEG is 2-31 with 31 being the worst quality.
The scale is linear with double the qscale being roughly half the bitrate.
Recommend trying values of 2-5.
You can use a value of 1 but you must add the -qmin 1 output option (because the de...
Find the day of a week
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df = data.frame(date=c("2012-02-01", "2012-02-01", "2012-02-02"))
df$day <- weekdays(as.Date(df$date))
df
## date day
## 1 2012-02-01 Wednesday
## 2 2012-02-01 Wednesday
## 3 2012-02-02 Thursday
Edit: Just to show another way...
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Why should eval be avoided in Bash, and what should I use instead?
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There's more to this problem than meets the eye. We'll start with the obvious: eval has the p...
Print a file, skipping the first X lines, in Bash [duplicate]
I have a very long file which I want to print, skipping the first 1,000,000 lines, for example.
13 Answers
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How do I get the fragment identifier (value after hash #) from a URL?
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No need for jQuery
var type = window.location.hash.substr(1);
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Exit a Script On Error
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138
Are you looking for exit?
This is the best bash guide around.
http://tldp.org/LDP/abs/html/
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How can I get Docker Linux container information from within the container itself?
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Moving average or running mean
... NumPy function or module for Python that calculates the running mean of a 1D array given a specific window?
27 Answers
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How to reshape data from long to wide format
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11 Answers
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C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
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Okay, I finally have a real answer. I sort of worked it out on my own, but only after Lucian Wis...