NAME
Panotools::Photos - Photo sets
SYNOPSIS
Query sets of photos
DESCRIPTION
A collection of photos has possibilities, it could be one or more panoramas or a bracketed set. This module provides some methods for describing groups of photos based on available metadata
USAGE
Create a new object like so:
my $photos = new Panotools::Photos;
Alternatively supply some filenames:
my $photos = new Panotools::Photos ('DSC_0001.JPG', 'DSC_0002.JPG');
- Paths
-
Add to or get the list of image filenames:
$photos->Paths ('DSC_0003.JPG', 'DSC_0004.JPG'); my @paths = $photos->Paths;
- Stub
-
Construct a stub filename from the names of the first and last images in the list.
my $stub = $photos->Stub;
e.g. DSC_0001.JPG DSC_0002.JPG DSC_0003.JPG -> DSC_0001-DSC_0003
- Bracketed
-
Query to discover if this is a likely bracketed set. i.e. is the total number of photos divisible by the number of different exposures:
&do_stuff if ($photos->Bracketed);
- Layered
-
Query to discover if this is a layered set, i.e. there is a large exposure difference in the set, but it isn't bracketed.
&do_stuff if ($photos->Layered);
By default the threshold is 4, e.g. exposures varying between 2 and 1/2 seconds indicate layers. Vary this threshold like so:
&do_stuff if ($photos->Layered (2));
- Speeds
-
Get a list of exposure times sorted with longest exposure first
@speeds = @{$photos->Speeds};
- SplitInterval
-
Given a set of photos, split it into a one or more sets by looking at the variation of time interval between shots. e.g. typically the interval between shots in a panorama varies by less than 15 seconds. A variation greater than that indicates the start of the next panorama:
my @sets = $photos->SplitInterval (15);
Sets with an average interval greater than 4x this variation are not considered panoramas at all and discarded.
- AverageInterval
-
Get the average time between shots:
$average = $photos->AverageInterval;
- FOV FocalLength Rotation
-
Get the Angle of View in degrees of the first photo:
$photos->FOV;
..or any other photo (-1 is last):
$photos->FOV (123);
Returns undef if the FOV can't be calculated.
- Eev
-
Get an EV value for a photo, this will be guessed from partial EXIF data:
$photos->Eev ($index);
- AverageRGB
-
Find the mean average colour balance for all photos:
($red, $green, $blue) = $photos->AverageRGB;