How to Generate Animated Webp from a GIF image

[AmitSonkhiya]

I'm trying to figure out generating animated webp from a GIF image.
My purpose is reducing file size (from 2-10 MB to comparatively lesser).

From this Stackoverflow link, I have tried as follow:

$image = Vips\Image::newFromFile('something.gif', [
    'n' => -1,
    'access' => 'sequential'
]); 
$image->writeToFile('something.webp');

However, that is causing the following error:

optional argument 'n' doesn't exist.

From the Libvips documentation, I think that the argument ``'n' has removed.
So after removing the argument 'n' => -1, the webp image is generated but it is loosing the animation.

What is the proper code to generate animated webp from an animated GIF image with lesser file size?

Thank you

PHP version: 8.2.5
Libvips version: 8.14.2
PHP vips version: 2.1.1
OS: Mac OS
GIF size: 1.94 MB
Generated webp size (without animation): 25

[jcupitt]

Hi @AmitSonkhiya, it should work, I guess your libvips has been built without a GIF loader:

https://www.libvips.org/API/current/VipsForeignSave.html#vips-gifload

[AmitSonkhiya]

Hi,
Thank you for quick response.

How do I verify if the gifload is absent?
I have run vips gifload on CLI and getting usages description, through I'm not sure it is the correct way to verify.

Thank you

[jcupitt]

Could you have two libvipses installed? I tried this:

#!/usr/bin/env php
<?php
require __DIR__ . '/vendor/autoload.php';
use Jcupitt\Vips;

# Vips\Config::setLogger(new Vips\DebugLogger());
$version =  Vips\Config::version();
echo "libvips version $version\n";

$image = Vips\Image::newFromFile("/Users/john/pics/3198.gif", [
    "n" => -1,
    "access" => "sequential"
]);
$image->writeToFile("x.webp");

And it works fine on my mac. That's with libvips from homebrew.

[jcupitt]

ie. perhaps your php is picking up a very old version or different version libvips.

[AmitSonkhiya]

Hi,

libsvips version 8.14.2

Thank you for the support.
Your example works fine and I'm getting the animated webp.
I was simply appending .webp to original GIF name as target file (something.gif => something.gif.webp).
I guess here was the issue. After giving another random name, it worked perfectly.

Just a quick question more.
How could additionally reduce the target webp file size?
GIF size: 1.94MB
Animated webp size: 420KB

Thank you

[jcupitt]

You can turn down Q to get more highly compressed images:

$image->writeToFile("x.webp", [
    "Q" => 30
]);

Though of course quality may become worse, and the improvement will depend on the image contents.

[jcupitt]

I was simply appending .webp to original GIF name as target file (something.gif => something.gif.webp). I guess here was the issue. After giving another random name, it worked perfectly.

That should be fine, you probably had some other minor bug.

[AmitSonkhiya]

Hi @jcupitt ,

I'm opening the discussion again as I'm stuck here.

With the Image::thumbnail() method, I'm able to create thumbnails of given sizes.
However, as obvious, thumbnails are losing the animation.

I have tried the resize method but that requires a scale parameter rather than specific size (width).
How do I create thumbnails that preserve the animation (GIF and Webp)?
I could not find any purposeful argument :-/

(Image::thumbnail('image.webp', 384))->writeToFile('image_384.jpg');

Thank you again

[jcupitt]

Perhaps your libvips has been built without webp support?

[jcupitt]

How do I force PHP Vips to consider width only in the account and produce height proportional to it?

Just use a huge value for the height parameter, eg. 10000000.

[AmitSonkhiya]

@jcupitt

Thank you for the software and much appreciated support.
I had a slash missing in the path.

Fixing it made everything to work smoothly.

PS: I understand there are pretty efforts behind the library. Still having FAQs/TIPs section somewhere would be effective?
For example, as you told image.gif[n=-1] for animated thumbnails or load all frames.
Or setting up height to a big number for width constraint.
Through, official docs have their own stand, just searching them with human keywords would be a breeze.
A Google search leads no where.
It will also helpful for you to answer basic questions like I asked through a link to them.
And it will attract more developers.

Thank you

[jcupitt]

I tried to improve the thumbnail docs a bit: libvips/libvips@ce99675

[AmitSonkhiya]

It is indeed better. 😊

[AmitSonkhiya]

I'm still digging more. Uhm!

@jcupitt I'm able to create SQUARE static thumbnails using the following code.

Vips\Image::thumbnail('source.jpg'), 384, ['height' => 384, 'crop' => 'attention'])
        ->writeToFile('target.jpg', ['strip' => 'strip']);

I'm curious if we can generate a square thumbnail from a rectangle image while preserving the animation?
And if yes then how and if it would be memory-extensive due to number of frames?
Of course, source.gif[n=-1] in the code above generates thumbnails but loses animation if the aspect ratio is changed.

Thank you

[jcupitt]

There's an enhancement issue for adding animated thumbnail crop libvips/libvips#2668

But no one's done the work yet.

[AmitSonkhiya]

I see, no option other than waiting until an expert incorporate this enhancement.