Tiny GIF Converter

This is a tiny gif converter aiming to generate high quality yet compact gif images for WeChat official account writers or bloggers. This converter takes in a video or gif file, then it converts or compresses the file to a gif image, which is compatible with WeChat official account. The program has been tested on the Mac OS X with Python 3.6 environment.

The converter uses FFmpeg to extract frames, then it uses Gifski to generate high quality gif images. The GUI of this program is created by using PySimpleGUI, just like its name, which is a simple and people-friendly Python GUI. Both FFmpeg and PySimpleGUI are cross-platform libraries, so it should be worked well on other OS theoretically. Please let me know if something went south in Windows or Linux.

Appearance

Here is what the GUI looks like. You can change the theme which you like. Once you setup parameters, click the Convert button to start. The process just takes a few seconds.

DarkTeal2	DarkPurple	LightBrown3

Sample

Here is a samlpe gif generated by this converter. Its resolution is 480 × 270 and FPS is 10. Notice that the file size is just 4.4M (no frame skipping). The sample file is captured from a YouTube Channel called Carfection.

Method

It seems a paradox that we can generate a high quality gif file yet keep it in a relatively small size. The trick here is generating a custom color palette, so we can make full use of the color space and discard colors we don’t need.

As you probably know, GIF is limited to a palette of 256 colors. And by default, FFmpeg just uses a generic palette that tries to cover the whole color space in order to support the largest variety of content.

This converter uses Gifski to generate per-frame palettes, meanwhile, combines palettes across frames, achieving thousands of colors per frame for maximum quality. For more details about the color palette, please see the reference links down below.

Requirements

• FFmpeg
• Gifski
• PySimpleGUI

Setup

Here is an installation guidance for Mac users. Windows and Linux are following the same setup procedure.

Mac OS X

The simplest way to install FFmpeg and Gifski on Mac is using Homebrew. Run the following command in macOS Terminal (zsh) to install it:

$ /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"

Once it is done, use the following command to install FFmpeg and Gifski:

$ brew install ffmpeg
$ brew install gifski

The last step is installing PySimpleGUI:

$ pip install pysimplegui

Here Miniconda is recommended, which provides a lightweight virtual environment for us.

Now you are all set!

Run

Use the following command to run the program:

$ python main.py

I may release an executable file in the future, sorry for the inconvenience for now.

The first packaged app for Mac users is released. If you don't have a Python interpreter on your computer, you can download the zip file. Unzip it then run the following command in Terminal:

$ cd /Path of the app
$ ./TGC

If you still don't want to install anything, you also can try it on Colab.

Some files are provided in the sample folder just for testing. They are from T. E. D. D. 1104 and an ICLR 2020 paper respectively.

Overview

// main.py

import PySimpleGUI as sg

from convert_to_gif import gif_converter

# ---------------------- Window Layout ---------------------- #
layout = [***]

# ---------------------- Create Window ---------------------- #
window = sg.Window('Tiny GIF Converter', layout)

# Event Loop to process "events" and get the "values" of the inputs
while True:
    event, values = window.read()
    if event in (None, 'Cancel'):  # if user closes window or clicks cancel
        break
    elif event == 'Convert':
        # Converting
        if gif_converter(**kwargs) == 'Done':
            break

// convert_to_gif.py

import subprocess

# Extract frames
subprocess.call([
    'ffmpeg',
    '-ss', start_time,  # start time
    '-t', duration,  # duration
    '-i', load_path,  # original file dir
    '-vf', "fps=" + fps + ", scale=" + frame_width + ":-1",
    '-pix_fmt', 'rgb24',  # pixel formats
    # output file dir
    '-y', 'tmp/frame%04d.png',
    ])

# Create GIF
out_file_name = os.path.basename(load_path) + '_converted.gif'
ex = subprocess.Popen("gifski --fps " + fps + " -o " +
        os.path.join(save_path, out_file_name) +
        " tmp/frame*.png", 
        stdout=subprocess.PIPE,
        universal_newlines=True, shell=True)

while ex.poll() == None:
    yield ex.stdout.readline()

References

1. https://superuser.com/questions/556029/how-do-i-convert-a-video-to-gif-using-ffmpeg-with-reasonable-quality

2. http://blog.pkh.me/p/21-high-quality-gif-with-ffmpeg.html

3. https://stackoverflow.com/questions/42980663/ffmpeg-high-quality-animated-gif