Friday, 1 February 2008

Exif auto-rotate & scale your photos

Typically after a journey to new place I finish with hundreds of photos from my camera. When I am browsing it on linux (or mac osx) everything is ok - gwenview can read EXIF rotation data and show them in proper direction (rotate on the fly). The problem begin when you upload such "good" portrait image or send it by email - it will be 90deg rotated. Ooops!

A small script can fix it and create subdirectories with 1280x1024 and 800x600 scaled images. It also rotates original images lossless preserving original EXIF data - don't be afraid about the quality!

To use this, simply add packages: imagemagick, exiftran & perl bindings Image::Magick.

#!/usr/bin/perl -w
`exiftran -aip *.JPG`;
`exiftran -aip *.jpg`;

use strict;
use Image::Magick;
use Cwd;

my $currdir = ( getcwd =~ m{([^/]+)$} )[0];

my $webdir = $currdir . '_to1280';
my $web800 = $currdir . '_to800';
print "Creating dirs: $webdir, $web800\n";
mkdir $webdir;
mkdir $web800;

print $| = 1;
foreach my $filename (<*.jpg>, <*.JPG>) {
# read this
my $image = Image::Magick->new();

# scale it
print "$filename ";
$image->Thumbnail(geometry => '1280x1024>');
$image->write($webdir . '/' . lc($filename));

$image->Thumbnail(geometry => '800x600>');
$image->write($web800 . '/' . lc($filename));
print ".\n";


andy-shev said...

Why did not to use RenRot?

Adam Bartosik said...

With windows you can use JPEG Lossless Rotator,

In batch mode just simply type in your photo directory:

jpegr.exe -auto .

to fix their rotation (however it is annoying to confirm the question - it is not a batch mode).
Still too much hassle instead of just one quick button (remember Amazon 1-click-to-buy feature)

[slawko] said...

I think you should make it case insensitive oon the input (why differentiate between jpg an JPG) and besides, the output files should be lower case only :)