Julia script to make a short looping gif playing a longer video.

movie_gif.jl

using GLMakie
using VideoIO

GLMakie.activate!(inline=true) # Show plots in VSCode

# Open the video file
video = VideoIO.openvideo("sprite_fright_60x60.mp4")
frames = collect(video)
close(video)

Video properties
framerate = 10
duration = 6.3  # Duration in seconds
total_frames = round(Int, framerate * duration)
n_rows = 10
n_cols = 10

# Setup canvas
fig = Figure(size = (600, 600), figure_padding = 0)
ax = Axis(fig[1,1], limits = (0,600,0,600), aspect = 1, backgroundcolor = :black)
# Can't figure out why I have to run this again to get an actual 600x600 px figure.
fig = Figure(size = (600, 600), figure_padding = 0)
ax = Axis(fig[1,1], limits = (0,600,0,600), aspect = 1, backgroundcolor = :black)
hidedecorations!(ax)
hidespines!(ax)
ax.yreversed = true

function makeframe(t, part)
    frame_idx = floor(Int, total_frames*part + t*total_frames + 1)

    # zero indexed row and col.
    row = part ÷ n_rows
    even_row = row % 2 == 0

    if (even_row)
        col = part % n_cols
    else 
        col = n_cols - (part % n_cols) - 1
    end

    first_col = col == 0
    last_col = col == n_cols - 1
    
    img = image!(ax, rotl90(frames[frame_idx]))
    

    y_start = 60 * row
    x_start = 60 * col

    if ((first_col && !even_row) || (last_col && even_row))
        # Move down
        translate!(img, x_start, y_start + t*60)
    elseif (even_row)
        translate!(img, x_start + t*60, y_start)
    else
        translate!(img, x_start - t*60, y_start)
    end
end

# Create and save the animation
record(fig, "output.gif", 0:total_frames; framerate=framerate) do i
    empty!(ax)
    
    for part = 98:-1:0
        makeframe(i/total_frames,part)
    end
end