Create .GIF from .PNG on Android

cgiteach · April 20, 2019, 7:50am

Hi,

I’m looking for help to implement a plugin, or custom C++ module, or modified engine source that would take a series of .PNG files from a specific location and turn them into a .GIF which would be saved on the device.

That’s it.

The gist is that we’re taking screenshots from an AR app and we want to record them as a GIF for easier distribution. Hence this is targeting UE4.22 on ARCore compatible hardware, so the good stuff. It has to work on phones we have physical access to, so we can tweak their security settings and allow any permissions necessary.

If you feel the GIF would be easier created on the fly, without first taking the screenshots that’s fine with me.
If you feel it would be 10 times easier to make a GIF from .JPG or another format we can probably use a plugin to save screenshots as something else than .PNG
If you have the luxury, I would prefer encoding in higher quality rather than lower. The output must be under 20 MB and we can easily tweak the frequency of the frames.

**It has to be done quite fast, ideally within a week. **Not interested in polished product nor in IP if you want to put this later on the Marketplace. It’s fine if it only works in development build.

PRO tips:
Use existing libraries that seem to have everything ready, just in JAVA, so it seems to me you should just create a JAVA wrapper or figure out if/how Unreal.js from UE4 marketplace could work on Android.
Here are some GIT repos for GIF making:

github.com

nbadal/android-gif-encoder/blob/master/GifEncoder.java

import java.io.IOException;
import java.io.OutputStream;

import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Paint;

public class AnimatedGifEncoder {

	  protected int width; // image size

	  protected int height;
	  
	  protected int x = 0;
	  
	  protected int y = 0;

	  protected int transparent = -1; // transparent color if given

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Also these link seem useful:

cgiteach · April 20, 2019, 8:27am

Forgot to mention, the phones will have internet access. If you feel it’s 10X simpler to integrate this into an Android app than that’s fine as well as an approach:
https://apiv2.online-convert.com/

cgiteach · April 23, 2019, 10:28am

After testing, the online-convert.com approach doesn’t work as you can’t generate animated GIFs from multiple images.
Is there really no-one with experience in GIF making.

As an extra simplification I could also go with .mp4 instead of .gif, perhaps using ffmpeg.

Thanks