Create animated GIFs using mpv

mpv-gif.lua

-- Create animated GIFs with mpv
-- Requires ffmpeg.
-- Adapted from http://blog.pkh.me/p/21-high-quality-gif-with-ffmpeg.html
-- Usage: "g" to set start frame, "G" to set end frame, "Ctrl+g" to create.
local msg = require 'mp.msg'

-- Set this to the filters to pass into ffmpeg's -vf option.
-- filters="fps=24,scale=320:-1:flags=lanczos"
filters="fps=15,scale=540:-1:flags=lanczos"

start_time = -1
end_time = -1
palette="/tmp/palette.png"

function make_gif_with_subtitles()
    make_gif_internal(true)
end

function make_gif()
    make_gif_internal(false)
end

function make_gif_internal(burn_subtitles)
    local start_time_l = start_time
    local end_time_l = end_time
    if start_time_l == -1 or end_time_l == -1 or start_time_l >= end_time_l then
        mp.osd_message("Invalid start/end time.")
        return
    end

    mp.osd_message("Creating GIF.")

    -- shell escape
    function esc(s)
        return string.gsub(s, "'", "'\\''")
    end

    local pathname = mp.get_property("working-directory", "") .. "/" .. mp.get_property("path", "")
    local trim_filters = esc(filters)
    if burn_subtitles then
        -- TODO: get current subtitle
        trim_filters = trim_filters .. string.format(",subtitles=%s", esc(pathname))
    end

    local position = start_time_l
    local duration = end_time_l - start_time_l

    -- first, create the palette
    args = string.format("ffmpeg -v warning -ss %s -t %s -i '%s' -vf '%s,palettegen' -y '%s'", position, duration, esc(pathname), esc(trim_filters), esc(palette))
    msg.debug(args)
    os.execute(args)

    -- then, make the gif
    stream_path = mp.get_property("working-directory") .. "/" .. mp.get_property("path")
    local working_path = get_containing_path(stream_path)
    local filename = mp.get_property("filename/no-ext")
    local file_path = working_path .. filename

    -- increment filename
    for i=0,999 do
        local fn = string.format('%s_%03d.gif',file_path,i)
        if not file_exists(fn) then
            gifname = fn
            break
        end
    end
    if not gifname then
        mp.osd_message('No available filenames!')
        return
    end

    args = string.format("ffmpeg -v warning -ss %s -t %s -i '%s' -i '%s' -lavfi '%s [x]; [x][1:v] paletteuse' -y '%s'", position, duration, esc(pathname), esc(palette), esc(trim_filters), esc(gifname))
    os.execute(args)

    msg.info("GIF created.")
    mp.osd_message("GIF created.")
end

function set_gif_start()
    start_time = mp.get_property_number("time-pos", -1)
    mp.osd_message("GIF Start: " .. start_time)
end

function set_gif_end()
    end_time = mp.get_property_number("time-pos", -1)
    mp.osd_message("GIF End: " .. end_time)
end

function file_exists(name)
    local f=io.open(name,"r")
    if f~=nil then io.close(f) return true else return false end
end

function get_containing_path(str,sep)
    sep=sep or package.config:sub(1,1)
    return str:match("(.*"..sep..")")
end

mp.add_key_binding("g", "set_gif_start", set_gif_start)
mp.add_key_binding("G", "set_gif_end", set_gif_end)
mp.add_key_binding("Ctrl+g", "make_gif", make_gif)
mp.add_key_binding("Ctrl+G", "make_gif_with_subtitles", make_gif_with_subtitles)

Does it actually work on linux? It seems script shows message "GIF created" only, there is no gif file.

So the problem here is relatively simple. The script assumes that the file opened is given as a relative path, which isn't true if mpv has been opened using the .application files (i.e. double click on the video in the file browser).

The relatively simple solution for this is to add the following function:

function get_path()
    local file_path = mp.get_property("path", "")
    if not string.sub(file_path,1,1) == "/" then  -- probably relative path
        file_path = mp.get_property("working-directory", "") .. "/" .. file_path
    end

    return file_path
end

And replace the mentions of mp.get_property("working-directory") .. "/" .. mp.get_property("path") (or similar) with get_path()

Here is the improved version: https://github.com/arandomliz/mpv-gif-generator
Also subtitles actually work and the commands are run safely with async