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Understanding :source option of has_one/has_many through of Rails
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Sometimes, you want to use different names for different associations. If the name you want to u...
What is the difference between a WCF Service Application and a WCF Service Library?
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edited Jan 26 '11 at 12:05
answered Jul 30 '09 at 4:34
And...
SQL Server 2008: how do I grant privileges to a username?
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marc_smarc_s
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switch() statement usage
... expr min lq median uq max
1 test1("mean") 709 771 864 951 16122411
2 test2("mean") 1007 1073 1147 1223 8012202
> microbenchmark(test1('trimmed'), test2('trimmed'), times=1e6)
Unit: nanoseconds
expr min lq median uq max
1 test1("trimmed") 733 792 ...
Export Postgresql table data using pgAdmin
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edited Nov 25 '16 at 15:06
Alfonso Tienda
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When tracing out variables in the console, How to create a new line?
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answered Apr 26 '13 at 15:01
Selvakumar ArumugamSelvakumar Arumugam
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How to redirect single url in nginx?
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answered Aug 4 '13 at 1:57
Mohammad AbuShadyMohammad AbuShady
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How to raise a ValueError?
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NPENPE
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What is the difference between Caching and Memoization?
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5 Answers
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How can I extract a good quality JPEG image from a video file with ffmpeg?
...le 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 default is -qmin 2).
To output a series of images:
ffmpeg -i input.mp4 -qscale:v 2 output_%03d.jpg
See the image muxer documentation for mo...