The webp served instead of png has black background instead of transparent

I have the same issue!

Yes, I’m aware. I probably should add a warning in the UI about this until this is fixed (if it can be fixed).

Can you tell me the version number of your GD? (do a test conversion and view the log). In test conversion, does “dice.png” fail while “palette-based-colors.png” succeeds?

See also: https://github.com/rosell-dk/webp-express/issues/374

I have done a lot of research and testing and unfortunately, it seems that all hope is lost for retaining alpha channel for webp on old Gd. Here is why

I would still appreciate your Gd version number in order to display a warning on affected platforms.

Hi Rosell.dk,
Thank you for the swift response!

Below is the log (GD Version: 2.1.1) :

Converter set to: gd

*WebP Convert 2.3.0*  ignited.
- PHP version: 7.0.33-0ubuntu0.16.04.6
- Server software: Apache/2.4.18 (Ubuntu)

Gd converter ignited

Options:
------------
The following options have been set explicitly. Note: it is the resulting options after merging down the "jpeg" and "png" options and any converter-prefixed options.
- source: (...)/test-pattern-tv.jpg
- destination: (...)/test-pattern-tv.jpg.webp
- default-quality: 70
- log-call-arguments: true
- max-quality: 80
- quality: "auto"

The following options have not been explicitly set, so using the following defaults:
- skip: false

The following options were supplied but are ignored because they are not supported by this converter:
- encoding
- metadata
- near-lossless
- skip-pngs
------------

GD Version: 2.1.1
image is true color
Quality of source is 93. This is higher than max-quality, so using max-quality instead (80)
Fixing corrupt webp by adding a zero byte (older versions of Gd had a bug, but this hack fixes it)

Converted image in 15 ms, reducing file size with 73% (went from 28 kb to 8 kb)

• This reply was modified 5 years, 1 month ago by RamConsulting.

Thanks, ramconsulting.

For those that experiences this, here are your options:

– Disable PNG. Gd isn’t very good at converting PNG anyway, as Gd cannot create lossless webp, only lossy webp
– Ask your host to upgrade Gd
– Ask your host to install imagick, vips or cwebp
– Use a cloud converter (ewww or connect to a remote webp-express)