gifAnimBegin not working as documented

[RannaAI]

Hello,
I'm not sure if this is known or not, I've been using the old version of the library because of these kind of errors, but since I'm forced to update the project I'm going through all libraries, I actually have an issue with gif creation.

This line :
firstFrame.gifAnimBegin(anim, 1, -1);

Throws:
TypeError: Argument 0 must be an integer

I assume that we moved to a better way to create gif using
const anim = new gd.GifAnim(image, {delay: 10});

but there is lack of documentation, I'm trying to achieve a transparent animated gif, and I'm still struggling.
Thank you for this awesome module.

[RannaAI]

Hello again,
Also based on the new code I'm not able to generate a proper gif, I'm not sure what i'm doing wrong, here is an example :

const gd = require('node-gd');
(async ()=>{
    try{
    const a = await gd.createFromPng('./a.png');
    const b = await gd.createFromPng('./b.png');

    const anim = new gd.GifAnim(a, {delay: 10});
    anim.add(b, {delay: 10});
    anim.add(a, {delay: 10});
    anim.add(b, {delay: 10});
    anim.add(a, {delay: 10});

    await anim.end('./anim.gif');
    }catch(e){
        console.log(e)
    }
})();

a.png

b.png

result in anim.gif

Thanks

[y-a-v-a]

Hi @RannaAI thanks for reaching out! I didn't think anyone was still useing node-gd apart from myself...! So that's good news for me of course. The downside is your issue. I will have to look into this, and might take a week or so, since I maintain node-gd in my spare time, I hope you understand. But I will respond!
Regards, Vincent

[y-a-v-a]

Hi @RannaAI so far my findings are that creating an animated GIF from in-memory created images (i.e. not from external images) works as expected, and is part of the module's tests. But I will extend the test and see if I can add your images (if you allow me to) and see if I can find the issue.
Next to that, there might also be an issue outside of node-gd, which might be an issue at libgd's side (see their repo here: https://github.com/libgd/libgd ). When looking at their open issues, there are some related to GIFs. So I will take a further look in that direction too.
Regards, Vincent

[RannaAI]

Hi Vincent,
Thank you for your prompt reply, I've been using your library for almost 2 years now, and it works great, maybe that's why nobody is reporting issues, it just work as like charm.

Hi @RannaAI thanks for reaching out! I didn't think anyone was still useing node-gd apart from myself...! So that's good news for me of course. The downside is your issue. I will have to look into this, and might take a week or so, since I maintain node-gd in my spare time, I hope you understand. But I will respond!
Regards, Vincent

This issue is only related to the new version 2.x I guess. My previous code is still working fine with 1.6.1 but I really apreciated what you've done in 2.x whne I read your blog post and I wanted to update my code to use it instead. And yes take your time whenver you feel like or have spare time I will be available if you need any further information, so no rush since my app still up and running on the previous release 1.6.1.

Hi @RannaAI so far my findings are that creating an animated GIF from in-memory created images (i.e. not from external images) works as expected, and is part of the module's tests. But I will extend the test and see if I can add your images (if you allow me to) and see if I can find the issue.
Next to that, there might also be an issue outside of node-gd, which might be an issue at libgd's side (see their repo here: https://github.com/libgd/libgd ). When looking at their open issues, there are some related to GIFs. So I will take a further look in that direction too.
Regards, Vincent

Feel free to use anything I would share here, I hope I can contribute in a way or another.

Here is the result achieved with the old version(1.6.1):

var gd = require('node-gd');

var output = './anim161.gif';

var a = gd.createFromPng('./a.png');
var b = gd.createFromPng('./b.png');
a.alphaBlending(1);
a.saveAlpha(1);
b.alphaBlending(1);
b.saveAlpha(1);

var mA = gd.createFromPng('./a.png');
var firstFrame =gd.createSync(128,128);
firstFrame.colorTransparent(0x000000);
var whiteBackground = firstFrame.colorAllocate(0, 0, 0);
mA.copy(firstFrame, 0, 0, 0, 0, 128, 128);

firstFrame.gifAnimBegin(output, 1, 0);
firstFrame.gifAnimAdd(output, 1, 0, 0, 10, 1, null);

var totalFrames = [];
for(var i = 0; i < 4; i++) {
  totalFrames.push(i);
}

totalFrames.forEach(function(i, idx, arr) {
  var frame = gd.createSync(128, 128);
  frame.colorTransparent(0x000000);
  arr[idx] = frame;
  var whiteBackground = frame.colorAllocate(0, 0, 0);

  if(i%2==0)
    a.copy(frame, 0, 0, 0, 0, 128, 128);
  else
    b.copy(frame, 0, 0, 0, 0, 128, 128);
  var lastFrame = i === 0 ? firstFrame : arr[i - 1];
  frame.gifAnimAdd(output, 1, 0, 0, 10, 1, lastFrame);
  frame.destroy();
});

firstFrame.gifAnimEnd(output);
firstFrame.destroy();