Imgix returns bad result with gif animations


I want to share with you a problem I encounter with some gif animations and Imgix.
For exemple, I have a gif which weight 2.8mo. If I encode it to webp using Gimp with the "Lossless" option, it result in a file which weight 1.6mo. And the quality is still exactly the same. That is good.

But if I do the same thing using Imgx (?lossless=true&fm=webp), it result in a file which weight 4.7mo ! That is very bad.The lossless option seems to do nothing, the result is the same without it.

If I use the "q" option with the value 0, the result is also 1.6mo but as expected the quality is very degraded.


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Thanks for reaching out,

As far as I understood, it is an issue with Imigix where ?lossless=true&fm=web is not return the correct result.

Have you tried to reach out to their support?
From my side, I will try to reproduce the issue. Can you please share with me the gif file you are trying to encode?

Looking forward to your reply,


Thank you for your reply. Attached is gif that is not encoded correctly if we give it to imgix.


gif(2.8mo) => gimp(webp lossless) => webp(1.6mo)
gif(2.8mo) => imgix(?lossless=true&fm=webp) => webp(4.5mo)

So using gimp result in a 1.6mo webp and imgix result in a 4.5mo.

I didn't try to reach out to their support, can you share me the link to do so ? Maybe I have to create an account on their website.

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Thanks for the info, and I'm creating an issue for this to investigate.

For the reference can you provide your repository name (in a private message if necessary)?

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