mpv script to quickly create gifs, video clips, and sound clips

mpv-clip.lua

-- Create animated GIFs with mpv
-- Requires ffmpeg, gifski, exiftool, and vorbis-tools.
-- Based on github.com/Scheliux/mpv-gif-generator
-- Usage: "g" to set start frame, "G" to set end frame, 
-- "Ctrl+g" to create gif
-- "Ctrl+v" to create video clip
-- "Ctrl+a" to create audio clip
-- Metadata about the filename and timestamps will be written in the comment tag

local msg = require 'mp.msg'

home = os.getenv("HOME")

-- Quality Settings

gif_fps = 12
gif_width = 540
gif_quality = 90
gif_folder = home.."/mpv/gifs/"

vid_crf = 20
vid_width = -1
vid_folder = home.."/mpv/vid/"

snd_bitrate = 128
snd_folder = home.."/mpv/snd/"

gif_filters=string.format("fps=%s,scale=%s:-1:flags=lanczos", gif_fps, gif_width)
vid_filters=string.format("scale=%s:-1:flags=lanczos", vid_width)


start_time = -1
end_time = -1

mode = "gif"

function make()
	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

	local type = ""
	if mode=="gif" then
		type = "GIF"
	elseif mode=="vid" then
		type = "Video Clip"
	elseif mode=="snd" then
		type = "Sound Clip"
	end
	mp.osd_message("Creating "..type)

	function esc(s)
		return s:gsub("'", "'\\''")
	end

	local position = start_time_l
	local duration = end_time_l - start_time_l

	local path = mp.get_property("path")
	local directory = get_containing_path(path)
	local filename = mp.get_property("filename/no-ext")

	local extension = ""
	local directory = ""
	if mode=="gif" then
		extension = "gif"
		directory = gif_folder
	elseif mode=="vid" then
		extension = "mp4"
		directory = vid_folder
	elseif mode=="snd" then
		extension = "ogg"
		directory = snd_folder
	end

	os.execute("mkdir -p "..directory)

	for i=0,999 do
		local fn = string.format('%s_%03d.%s', directory..filename, i, extension)
		if not file_exists(fn) then
			outfile = fn
			break
		end
	end
	if not outfile then
		mp.osd_message('No available filenames!')
		return
	end

	if mode == "gif" then
		framenames = "/tmp/mpv/%04d.png"
		os.execute("mkdir -p /tmp/mpv && rm /tmp/mpv/*")
		os.execute(string.format("ffmpeg -ss %s -t %s -i '%s' -lavfi '%s' -y '%s'", position, duration, esc(path), gif_filters, framenames))
		os.execute(string.format("gifski --fps %s --quality %s /tmp/mpv/* -o '%s'", gif_fps, gif_quality, esc(outfile)))
	elseif mode == "vid" then
		os.execute(string.format("ffmpeg -ss %s -i '%s' -t %s -lavfi '%s' -async 1 -crf %s -y '%s'", position, esc(path), duration, vid_filters, vid_crf, esc(outfile)))
	elseif mode == "snd" then
		os.execute(string.format("ffmpeg -ss %s -t %s -i '%s' -vn -c:a libvorbis -ab %sk -y '%s'", position, duration, esc(path), snd_bitrate, esc(outfile)))
	end

	if file_exists(outfile) then
		if mode == "snd" then
			os.execute(string.format("vorbiscomment -wRt comment='%s %s %s' '%s'", esc(filename), position, duration, esc(outfile)))
		else
			os.execute(string.format("exiftool -overwrite_original_in_place -comment='%s %s %s' '%s'", esc(filename), position, duration, esc(outfile)))
		end
		msg.info(type.." created.")
		mp.osd_message(type.." created.")
	else
		msg.info("Failed to create "..type)
		mp.osd_message("Failed to create "..type)
	end
end

function make_gif()
	mode = "gif"
	make()
end

function make_vid()
	mode = "vid"
	make()
end

function make_snd()
	mode = "snd"
	make()
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+v", "make_vid", make_vid)
mp.add_key_binding("Ctrl+a", "make_snd", make_snd)