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Fastest way to extract frames using ffmpeg?
... video 38m07s long:
time ffmpeg -i input.mp4 -filter:v fps=fps=1/60 ffmpeg_%0d.bmp
1m36.029s
This takes long because ffmpeg parses the entire video file to get the desired frames.
time for i in {0..39} ; do ffmpeg -accurate_seek -ss `echo $i*60.0 | bc` -i input.mp4 -frames:v 1 period_down_$i....
What is the performance cost of having a virtual method in a C++ class?
... be non-virtual is an abominable policy.
– underscore_d
May 20 '17 at 19:34
add a comment
...
Pass complex parameters to [Theory]
... : IEnumerable<object[]>
{
private readonly List<object[]> _data = new List<object[]>
{
new object[] { "hello world", 'w', 6 },
new object[] { "goodnight moon", 'w', -1 }
};
public IEnumerator<object[]> GetEnumerator()
{ return _data.GetEn...
What is a stored procedure?
...tatype>
AS
<Body>
So for example:
CREATE PROCEDURE Users_GetUserInfo
@login nvarchar(30)=null
AS
SELECT * from [Users]
WHERE ISNULL(@login,login)=login
A benefit of stored procedures is that you can centralize data access logic into a single place that is then eas...
How can I use an array of function pointers?
...ointers.
void fun1()
{
}
void fun2()
{
}
void fun3()
{
}
void (*func_ptr[3])() = {fun1, fun2, fun3};
main()
{
int option;
printf("\nEnter function number you want");
printf("\nYou should not enter other than 0 , 1, 2"); /* because we have only 3 functions */
scanf("%d",&...
LEN function not including trailing spaces in SQL Server
...
I would use LEN(REPLACE(expr, ' ', '_')). This should work with varchar and nvarchar and strings containing special unicode control characters.
– Olivier Jacot-Descombes
Apr 24 '14 at 16:01
...
Using the Android Application class to persist data
...nController extends Application {
private static ApplicationController _appCtrl;
public static ApplicationController getAppCtrl()
{
return _appCtrl;
}
}
Because subclasses of Application also can obtain the Resources, you could access them simply when you define a static ...
Setting PATH environment variable in OSX permanently
...is the only solution that works on El Capitan. Better than modifying .bash_profile and .profile.
– IgorGanapolsky
Nov 29 '15 at 21:06
1
...
How does lucene index documents?
...robably the best more recent alternative is http://lucene.apache.org/core/3_6_2/fileformats.html
There's an even more recent version at http://lucene.apache.org/core/4_10_2/core/org/apache/lucene/codecs/lucene410/package-summary.html#package_description, but it seems to have less information in it ...
How can I quickly delete a line in VIM starting at the cursor position?
...atever was yanked before.
The true delete command in the OP's context is "_D (or "_C if insert mode is desired) This sends the deleted content into the black hole register, designated by "_, where it will bother no one ever again (although you can still undo this action using u).
That being said,...