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How do you convert an entire directory with ffmpeg?
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Previous answer will only create 1 output file called out.mov. To make a separate output file for each old movie, try this.
for i in *.avi;
do name=`echo "$i" | cut -d'.' -f1`
echo "$name"
ffmpeg -i "$i" "${name}.mov"
done
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Using [UIColor colorWithRed:green:blue:alpha:] doesn't work with UITableView seperatorColor?
...ur UIColor method requires a float from 0-1, not 0-255. You need to divide all your RGB values by 255.0, as follows:
self.tableView.seperatorColor = [UIColor colorWithRed:127.0f/255.0f green:127.0f/255.0f blue:127.0f/255.0f alpha:1.0f];
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What is the “assert” function?
... the program fail more obviously if an unexpected condition occurs.
For example:
assert(length >= 0); // die if length is negative.
You can also add a more informative message to be displayed if it fails like so:
assert(length >= 0 && "Whoops, length can't possibly be negative! (...
Why can templates only be implemented in the header file?
...f;
When reading this line, the compiler will create a new class (let's call it FooInt), which is equivalent to the following:
struct FooInt
{
int bar;
void doSomething(int param) {/* do stuff using int */}
}
Consequently, the compiler needs to have access to the implementation of the m...
PEP 8, why no spaces around '=' in keyword argument or a default parameter value?
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I guess that it is because a keyword argument is essentially different than a variable assignment.
For example, there is plenty of code like this:
kw1 = some_value
kw2 = some_value
kw3 = some_value
some_func(
1,
2,
kw1=kw1,
kw2=kw2,
kw3=kw3)
As you see, it mak...
How to remove all whitespace from a string?
...\r\v\fy \t\n\r\v\f"
## [4] NA
The base R approach: gsub
gsub replaces all instances of a string (fixed = TRUE) or regular expression (fixed = FALSE, the default) with another string. To remove all spaces, use:
gsub(" ", "", x, fixed = TRUE)
## [1] "xy" "←→" ...
Gradle store on local file system
... caches artifacts in USER_HOME/.gradle folder. The compiled scripts are usually in the .gradle folder in your project folder.
If you can't find the cache, maybe it's because you have not cached any artifacts yet. You can always see where Gradle has cached artifacts with a simple script:
apply plug...
How to limit UITableView row reordering to a section
...y bugs to occur on my setup, and it's notably different from apple's own example code on how to do this. FWIW! not saying it's wrong, just that I wonder if it's actually more complicated than this.
– Billy Gray
Jun 26 '13 at 16:13
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How do I change screen orientation in the Android emulator?
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Ctrl+F12 is the keyboard shortcut.
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Performance surprise with “as” and nullable types
...ts a slim syntax that also produces the best IL code.
The OP's original example...
object o = ...;
int? x = o as int?;
if (x.HasValue)
{
// ...use x.Value in here
}
becomes simply...
if (o is int x)
{
// ...use x in here
}
I have found that one common use for the new syntax is when yo...