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CSS Background Opacity [duplicate]
..., or use an RGBa (a for alpha) color for your background color.
Example, 50% faded black background:
<div style="background-color:rgba(0, 0, 0, 0.5);">
<div>
Text added.
</div>
</div>
...
How do I efficiently iterate over each entry in a Java Map?
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edited Mar 14 '19 at 22:20
Jared Burrows
48.5k2121 gold badges136136 silver badges173173 bronze badges
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How to remove gaps between subplots in matplotlib?
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103
You can use gridspec to control the spacing between axes. There's more information here.
impo...
Given an array of numbers, return array of products of all other numbers (no division)
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260
An explanation of polygenelubricants method is:
The trick is to construct the arrays (in the c...
How to check if hex color is “too black”?
...Int(c, 16); // convert rrggbb to decimal
var r = (rgb >> 16) & 0xff; // extract red
var g = (rgb >> 8) & 0xff; // extract green
var b = (rgb >> 0) & 0xff; // extract blue
var luma = 0.2126 * r + 0.7152 * g + 0.0722 * b; // per ITU-R BT.709
if (luma < 40) {
...
Ruby, remove last N characters from a string?
..._suffix!('123') # => "abc"
It's even significantly faster (almost 40% with the bang method) than the top answer. Here's the result of the same benchmark:
user system total real
chomp 0.949823 0.001025 0.950848 ( 0.951941)
range ...
Fast way to get image dimensions (not filesize)
...re the better. I emphasize fast because my images are quite big (up to 250 MB) and it takes soooo long to get the size with ImageMagick's identify because it obviously reads the images as a whole first.
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Java - get pixel array from image
...ation I was able to reduce the time of processing the pixels by more than 90% by just switching from the first approach to the second!
Here is a comparison I've setup to compare the two approaches:
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferByte;
import java.io.IOExceptio...
Position of least significant bit that is set
... position of the least significant bit that is set in an integer, e.g. for 0x0FF0 it would be 4.
22 Answers
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Fetch frame count with ffmpeg
...below.
ffprobe: Query the container
ffprobe -v error -select_streams v:0 -show_entries stream=nb_frames -of default=nokey=1:noprint_wrappers=1 input.mp4
This is a fast method.
Not all formats (such as Matroska) will report the number of frames resulting in the output of N/A. See the other met...