Create image with transparent background not working. about simpleimage

[claviska]

I can't replicate this. In addition, this page of the PHP manual has examples with imagefilledrectangle and imagefilledellipse, the latter of which shows an example with transparency. That would imply that both these functions do support it, so maybe your issue is with something else?

The first comment on the imagefill page also says that you can't fill an image with transparency. I tried it just to see, but it didn't work for me. I would be reluctant to use this method anyways, since it would be much more memory intensive to perform a flood fill than to fill just a rectangle.

Has anyone else run into a similar issue?

[maPer77]

hello claviska
The way I found to get a new transparent image. I created a transparent png small 10x10px, then open this PNG and then resize to the size I want.

$transparent = 'Transparent.png';
$img = new abeautifulsite\SimpleImage($transparent);
$img->resize(300, 100);

You can create a transparent image? I was trying with this code:

$img = new abeautifulsite\SimpleImage(null, 200, 100, array(0,0,0,127) );

Did I was not doing correctly?

tks

[claviska]

Ah, I didn't realize you were starting with a transparent image. I tried creating a new one from scratch like this:

$img = new abeautifulsite\SimpleImage(null, 200, 100, array(0,0,0,127) );

In theory, it should be black with 50% transparency, but it was black and opaque as you stated. Alpha-transparency can be tricky with GD, so it could be something we're doing wrong—or it could be that GD simply doesn't support it with this function.

Unfortunately, alpha-transparency in GD isn't my niche, so it will take some experimenting unless someone else can figure it out first.

[maPer77]

I started with a transparent image now, to solve the problem, before i was trying to:

$img = new abeautifulsite\SimpleImage(null, 200, 100, array(0,0,0,127) );

In theory it should work, but this did not work for me.

Also to do with the base64:

$transparent = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAABBJREFUeNpi+P//PwNAgAEACPwC/tuiTRYAAAAASUVORK5CYII=';
$img = new abeautifulsite\SimpleImage($transparent);
$img->resize(300, 100);

[claviska]

That might be a helpful workaround if we need to start with a transparent canvas. I'd still like to find out why transparency doesn't work as expected, though.

On Aug 21, 2013, at 10:03 PM, ciganox [email protected] wrote:

I started with a transparent image now, to solve the problem, before i was trying to:

$img = new abeautifulsite\SimpleImage(null, 200, 100, array(0,0,0,127) );

In theory it should work, but this did not work for me.

Also to do with the base64:

$transparent = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAABBJREFUeNpi+P//PwNAgAEACPwC/tuiTRYAAAAASUVORK5CYII=';
$img = new abeautifulsite\SimpleImage($transparent);
$img->resize(300, 100);

—
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[maPer77]

Maybe it's a problem of the GD library, but at least managed to find a solution, and there is a tip for those who need it.

PS. sorry if I write not right, because I use google translator

[claviska]

This will work now:

$img = new abeautifulsite\SimpleImage(null, 500, 500, array(0,0,0,64) );
$img->save('50-percent-transparent.png');

Just remember that the alpha value must be 0-127, zero being opaque and 127 being transparent. I was getting this confused with the 256 levels in each color channel.

[maPer77]

thanks