How to Find if an Image is Animatable

[AmitSonkhiya]

Hi again,

I was trying to find a function in Libvips docs that could return image iterations as an integer.
Preciously, I would like to find if an image is animatable or not. Hence a boolean/BIT return value is sufficient as well.

PHP getimageiterations() function gives a BIT value for this purpose and I would like to find if Libvips has a similar function for the same.

Is there any function in Libvips to find if an image is animatable, specially Webp images?

Thank you

PS: It is pretty hard to find functions for purposes.
I wish there could be a feature in the official documentation to search with related words.
I tried Google but it yield nothing.

[jcupitt]

Hello @AmitSonkhiya,

You need to look at the image metadata. For example:

$ vipsheader -a dancing_banana2.lossless.webp 
dancing_banana2.lossless.webp: 990x1050 uchar, 4 bands, srgb, webpload
width: 990
height: 1050
bands: 4
format: uchar
coding: none
interpretation: srgb
xoffset: 0
yoffset: 0
xres: 1
yres: 1
filename: dancing_banana2.lossless.webp
vips-loader: webpload
loop: 0
delay: 100 100 100 100 100 100 100 100 
n-pages: 8

In PHP you can use eg. $image->get("n") to get the number of frames in an animation.

I wish there could be a feature in the official documentation to search with related words.

I usually use the function list:

https://www.libvips.org/API/current/func-list.html

[jcupitt]

There's also a "search" box at the top-right of the main PHP docs, of course:

https://libvips.github.io/php-vips/classes/Jcupitt-Vips-Image.html

[AmitSonkhiya]

Hello again @jcupitt

Thanks for letting me know.

$image->getType('n');
Outputs: 0  

Is it $image->get("n") or $image->get("n-pages")?
Because with n, it gives error: vips_image_get: field "n" not found.
With n-pages, it gives a number. I guess it is the frame count.

Thank you

About search, yep! those tools are useful.
Just I was searching on Google with human language terms like "Libvips/PHP vips check if an image is animatable", with a hope that it would lead me to some GitHub discussion or issue to find a clue. Hehe!!

[jcupitt]

Oop, n-pages, of course you're right.