wkhtmltoimage rendering colored noise for transparent PNGs

Question

I'm trying to render a HTML page as a PNG with transparency enabled.

This is the command that generates the images:

/usr/local/bin/wkhtmltoimage-amd64 --transparent --crop-h 300 --crop-w 210 temporary.html image.png

I have also tried enabling the format parameter.

/usr/local/bin/wkhtmltoimage-amd64 --transparent --format png --crop-h 300 --crop-w 210 temporary.html image.png

But the images are always showing colored noise like this. I am using the latest binaries from http://wkhtmltopdf.org/downloads.html.

enter image description here

Did you manage to find the answer for this? – Guido Aug 01 '15 at 14:27 — Guido, Aug 01 '15 at 14:27
hi, how did you managed this? – Marty Krishner May 13 '16 at 22:55 — Marty Krishner, May 13 '16 at 22:55

score 2 · Answer 1 · answered Jul 02 '16 at 15:39

2

Have you tried to increase the size of the image? I had such problem too with 100px images, but when I made width 500px I got no noise.

(Yes, I know that this is not a complete solution but perhaps it will help someone)

answered Jul 02 '16 at 15:39

Eugene

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score 0 · Answer 2 · answered Nov 30 '17 at 11:20

We get the same issue.

Without the crop values it seems to work.

We are under:

Windows
Xammp
wkhtmltoimage 0.12.4 (with patched qt)

Our possible solution is to make the browser of the wkhtmltoimage width height 300px and width 210px:

/usr/local/bin/wkhtmltoimage-amd64 --transparent --height 300 --width 210 temporary.html image.png

score 0 · Answer 3 · answered Feb 27 '18 at 19:04

0

The solution I figured out through trial-and-error is to set the width to something rather large. In my case, I set it to 8000. It apparently only uses the width as a guideline, so this theoretically should be a safe solution.

answered Feb 27 '18 at 19:04

TBrenner

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2
9
8

wkhtmltoimage rendering colored noise for transparent PNGs

3 Answers3