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Fastest way to extract frames using ffmpeg?
...ideo 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.bm...
Is there a best practice for generating html with javascript
...nce seen in the first method is likely because the result string must be reallocated 200 times, and memory allocations can be slow. After two iterations you have "testingtesting". After three iterations, that string is thrown away and memory with enough room for "testingtestingtesting" is allocate...
What is the memory consumption of an object in Java?
... tell you, so long as the program gives the same answers.
It might allocate some temporary Objects on the stack.
It may optimize some variables or method calls totally out of existence replacing them with constants.
It might version methods or loops, i.e. compile two versions of a meth...
Can I force a UITableView to hide the separator between empty cells? [duplicate]
...ra separators from tableview
self.tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectZero];
}
For previous versions
You could add this to your TableViewController (this will work for any number of sections):
- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:...
What does immutable mean?
...ed in will not be modified. Once you create a string "foo", some memory is allocated to store the value "foo". This memory will not be altered. If you modify the string with, say, substr(1), a new string is created and a different part of memory is allocated which will store "oo". Now you have two s...
When to catch java.lang.Error?
...in multithreaded applications, or is there a significant risk that smaller allocations in other threads fail because of it? … presumably only if your arrays were just small enough to be allocated, but left nothing for anyone else.
– PJTraill
Jun 11 '15 at 14:...
Append value to empty vector in R?
... avoided".
As BrodieG mentioned in the comments: it is much better to pre-allocate a vector of the desired length, then set the element values in the loop.
Here are several ways to append values to a vector. All of them are discouraged.
Appending to a vector in a loop
# one way
for (i in 1:le...
Swift compiler error: “non-modular header inside framework module”
.... Still getting the error with Parse. Xcode 7.3.1
– C0D3
Jun 15 '16 at 19:34
I had to restart XCode after making this ...
Advantages of Binary Search Trees over Hash Tables
... instance, if a hash function has a range R(h) = 0...100, then you need to allocate an array of 100 (pointers-to) elements, even if you are just hashing 20 elements. If you were to use a binary search tree to store the same information, you would only allocate as much space as you needed, as well as...
Remove files from Git commit
... case), and set the command as fixup:
pick 35c23c2 the first commit
fixup 0d78b28 remove unwanted files
You should be good after saving the file.
To finish :
git push -f
If you unfortunately get conflicts, you have to solve them manually.
...