Tk::Animation - Display sequence of Tk::Photo images
use Tk::Animation my $img = $widget->Animation(-format => gif, -file => somefile.gif); $img->add_frame(@images); $img->start_animation; $img->start_animation( $period ); $img->next_image; $img->prev_image; $img->set_image( 0 .. $#frames ); $img->pause_animation; $img->resume_animation( $period ); $img->fast_forward( $multiplier ); $img->fast_reverse( $multiplier ); $img->stop_animation; $img->set_disposal_method( $boolean );
In the simple case when Animation is passed a GIF89
style GIF with multiple 'frames', it will build an internal array of
Photo images.
The add_frame method adds images to the sequence. It is
provided to allow animations to be constructed from separate images. All
images must be Photos and should all be the same size.
start_animation($period) then initiates a
repeat with specified $period to
sequence through these images. As for raw repeat
$period is in milliseconds, for a 50Hz monitor it
should be at least 20ms. If $period is omitted it
is determined from the GIF metadata (see below), or if this is not
possible it defaults to 100 milliseconds.
stop_animation cancels the repeat and
resets the image to the first image in the sequence.
For fine-grained control next_image and
prev_image move one frame forward or backward.
set_image randomly positions the animation to a particular
frame.
pause_animation pauses the movie and
resume_animation continues from the pause point.
fast_forward and fast_reverse speed through
the movie either forwards or backwards. $multiplier
specifies how much faster the animation moves.
If Image::Info is installed, then the repeat period time and disposal
method of GIF animations are determined from the GIF metadata directly.
Otherwise the disposal method must be set manually by using
set_disposal_method (1 for blanking the previous images, 0
for leaving the previous images as is). The repeat period time may be
given in the start_animation method.
set_disposal_method was formerly known as
blank method, but the naming of this method was a
mistake.
If the disposal method is not set correctly, either by
set_disposal_method or by determining from the GIF
metadata, then the following may happen: By default Animation leaves the
previous movie frame in the animation photo. Many times overlaying
subsequent frames produces a composite that looks blurred.
This module should not depend on a module which is not declared as a dependency (Image::Info).
The delays between images may vary in a GIF animation. This cannot be handled by this module yet.
The handling of the various disposal methods is not correct.