CODEWITHSUNDEEP
phppngtcpdf
user2148134
user2148134

Reputation: 89

png image in pdf generated by TCPDF shows .. black background

I am developing a pdf using TCPDF . But when I try to print a PNG image the background of the image in pdf looks dark ..

Please help me .. If any one know about its solution

Regards

Upvotes: 3

Views: 4009

Answers (4)

Antony
Antony

Reputation: 4340

For anyone else looking for an answer to this - Example 42 on the TCPDF pages is your answer: https://tcpdf.org/examples/example_042/

It illustrates text under alpha image like this:

enter image description here

Upvotes: -1

Sherri
Sherri

Reputation: 943

This was happening to me for PNG images that were in the HTML that I was adding to the PDF (TCPDF) using writeHTMLCell.

I created the images with Gimp on Ubuntu and some of the images showed up with a black background. I eventually solved this by opening the PNG file, re-filling the transparent areas with pure white, then re-select that white area with the fuzzy select tool and delete it. So that the Channels tab looks like this:

enter image description here

With the Red, Green & Blue channels having white backgrounds and the alpha channel a black background. If that is inverted, then the PNG doesn't render correctly.

I then exported to PNG using these settings:

enter image description here

(Although for some greyscale images they looked washed out unless I changed the drop down to "automatic pixelformat".)

I'm sure someone with more graphics knowledge than me could understand more about what's going on here... but this was what I found after a lot of trial and error.

Upvotes: 0

jelhan
jelhan

Reputation: 6338

TCPDF uses GD or ImageMagick (via Imagick) for image manipulation. There is also built-in image manipulation. So it's a complex topic.

I had a transparency issue using TCPDF with ImageMagick on Debian 9. As you described the transparent background was replaced by black color in pdf generated. I could fix the issue by installing imagemagick-common package additionally to imagemagick-6.q16 and php-imagick.

Upvotes: -1

Display name
Display name

Reputation: 418

It depends on the transparency of the PNG. Possibly you are using alpha transparency in your png so please convert it to index transparency.

Upvotes: -1

Related Questions