File:Leucospermum cultivar gradual decrease of quality.jpg
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Size of this preview: 800 × 532 pixels. Other resolutions: 320 × 213 pixels | 640 × 425 pixels | 1,024 × 681 pixels | 1,280 × 851 pixels | 1,805 × 1,200 pixels.
Original file (1,805 × 1,200 pixels, file size: 876 KB, MIME type: image/jpeg)
File information
Structured data
Captions
Summary
[edit]DescriptionLeucospermum cultivar gradual decrease of quality.jpg |
English: Visualization of decreasing JPEG quality, with lowest quality in the middle, and highest at the left and right. |
Date | |
Source | File:Leucospermum cultivar.jpg |
Author | original made by User:Flying Freddy; I've applied an algorithm to visualize JPEG compression |
Other versions |
Following code was used to modify the original image:
#!/usr/bin/perl
use strict;
use warnings;
use v5.12;
use File::Temp qw/ tempdir /;
use Graphics::Magick;
use Math::Round qw(:all);
my $p = new Graphics::Magick;
$p->Read("Leucospermum_cultivar.jpg");
my ($width, $height) = $p->Get('width', 'height');
my $center = $width/2;
my $result = new Graphics::Magick;
$result->Set(size=>"${width}x${height}");
$result->Read();
$result->Set('quality', 100);
my $dir = tempdir(CLEANUP => 1);
my $chop = 16; # 1 MCU normally
for my $col (0..$width) {
next if $col%$chop;
my $current = $p->Clone();
$current->Crop(width => $chop, height => $height, x => $col, y => 0);
$current->Set('quality' => round_even(100*abs(($col-$center)/$center)));
my $filename = sprintf "%s/%05d.jpg", $dir, $col;
$current->Write($filename);
my $n = new Graphics::Magick;
$n->Read($filename);
$result->Composite( image => $n, x => $col, y => 0);
}
$result->Write('Leucospermum_cultivar_gradual_decrease_of_quality.jpg');
Licensing
[edit]This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 18:03, 16 September 2011 | 1,805 × 1,200 (876 KB) | AzaToth (talk | contribs) |
You cannot overwrite this file.
File usage on Commons
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Metadata
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