Resizing an animated WebP throws and error vips2webp: unable to encode

[metju]

I'm trying to resize some files, but it starts failing very soon. Might be hitting some WebP file dimension limit? I've noticed when dealing with animated gifs, it loads all the pages into one tall file when processing.

sharp('animated-webp-supported.webp', {animated: true})
	.resize(2880)
	.webp()
	.toFile('resized.webp')

the file I'm trying to convert (zipped, since GitHub doesn't like WebPs)

[lovell]

Hi, given you're resizing, you'll need to update the pageHeight, in this 12-page example to 2880 / 12 = 240.

-  .webp()
+  .webp({ pageHeight: 240 })

https://sharp.pixelplumbing.com/api-output#webp

See also #2275 for a future possible improvement relating to this.

[metju]

Hello, thanks for the response!

240 didn't work, but 2880 did (it's the new height of the resized image, right?). I've tried setting the pageHeight before asking, but I didn't guess the right value.

Is it possible to get the new exact height of a resized image? If not, and I have to calculate it myself, should I floor, ceil or round the value? I've tried the conversion with 2879 and 2881 and both didn't work, so this seems important to get right.

When setting the pageHeight, are there more than one correct value, that wouldn't produce the unable to encode error? Could then sharp do this work for us and calculate it?

[lovell]

I confused width and height in my answer, apologies. Glad you got it working. Please see #2275 for a future possible improvement relating to this.