skiptosilence.lua

--[[
  * skiptosilence.lua v.2023-08-27
  *
  * AUTHORS: detuur, microraptor, Eisa01
  * License: MIT
  * link: https://github.com/detuur/mpv-scripts
  * 
  * This script skips to the next silence in the file. The
  * intended use for this is to skip until the end of an
  * opening sequence, at which point there's often a short
  * period of silence.
  *
  * The default keybind is F3. You can change this by adding
  * the following line to your input.conf:
  *     KEY script-binding skip-to-silence
  * 
  * In order to tweak the script parameters, you can place the
  * text below, between the template markers, in a new file at
  * script-opts/skiptosilence.conf in mpv's user folder. The
  * parameters will be automatically loaded on start.
  *
  * Dev note about the used filters:
  * - `silencedetect` is an audio filter that listens for silence and
  * emits text output with details whenever silence is detected.
  * Filter documentation: https://ffmpeg.org/ffmpeg-filters.html
****************** TEMPLATE FOR skiptosilence.conf ******************
#--(#number). Maximum amount of noise to trigger, in terms of dB. Lower is more sensitive.
silence_audio_level=-40

#--(#number). Duration of the silence that will be detected to trigger skipping.
silence_duration=0.7

#--(0/#number). The first detcted silence_duration will be ignored for the defined seconds in this option, and it will continue skipping until the next silence_duration.
# (0 for disabled, or specify seconds).
ignore_silence_duration=1

#--(0/#number). Minimum amount of seconds accepted to skip until the configured silence_duration.
# (0 for disabled, or specify seconds)
min_skip_duration=0

#--(0/#number). Maximum amount of seconds accepted to skip until the configured silence_duration.
# (0 for disabled, or specify seconds)
max_skip_duration=120

#--(yes/no). Default is muted, however if audio was enabled due to custom mpv settings, the fast-forwarded audio can sound jarring.
force_mute_on_skip=no

#--(yes/no). Display osd messages when actions occur.
osd_msg=yes
************************** END OF TEMPLATE **************************
--]]

local o = {
	silence_audio_level = -40,
	silence_duration = 0.7,
	ignore_silence_duration=1,
	min_skip_duration = 0,
	max_skip_duration = 120,
	force_mute_on_skip = false,
	osd_msg = true,
}

(require 'mp.options').read_options(o)
local mp = require 'mp'
local msg = require 'mp.msg'

speed_state = 1
pause_state = false
mute_state = false
sub_state = nil
secondary_sub_state = nil
vid_state = nil
window_state = nil
skip_flag = false
initial_skip_time = 0

function restoreProp(timepos,pause)
	if not timepos then timepos = mp.get_property_number("time-pos") end
	if not pause then pause = pause_state end
	
	mp.set_property("vid", vid_state)
	mp.set_property("force-window", window_state)
	mp.set_property_bool("mute", mute_state)
	mp.set_property("speed", speed_state)
	mp.unobserve_property(foundSilence)
	mp.command("no-osd af remove @skiptosilence")
	mp.set_property_bool("pause", pause)	
	mp.set_property_number("time-pos", timepos)
	mp.set_property("sub-visibility", sub_state)
	mp.set_property("secondary-sub-visibility", secondary_sub_state)	
	timer:kill()
	skip_flag = false
end

function handleMinMaxDuration(timepos)
		if not skip_flag then return end
		if not timepos then timepos = mp.get_property_number("time-pos") end
		
		skip_duration = timepos - initial_skip_time
		if o.min_skip_duration > 0 and skip_duration <= o.min_skip_duration then
			restoreProp(initial_skip_time)
			if o.osd_msg then mp.osd_message('Skipping Cancelled\nSilence is less than configured minimum') end
			msg.info('Skipping Cancelled\nSilence is less than configured minimum')
			return true
		end
		if o.max_skip_duration > 0 and skip_duration >= o.max_skip_duration then
			restoreProp(initial_skip_time)
			if o.osd_msg then mp.osd_message('Skipping Cancelled\nSilence is more than configured maximum') end
			msg.info('Skipping Cancelled\nSilence is more than configured maximum')
			return true
		end
		return false
end

function skippedMessage()
	if o.osd_msg then mp.osd_message("Skipped to silence at " .. mp.get_property_osd("time-pos")) end
	msg.info("Skipped to silence at " .. mp.get_property_osd("time-pos"))
end

function doSkip()
	if skip_flag then return end
	initial_skip_time = (mp.get_property_native("time-pos") or 0)
	if math.floor(initial_skip_time) == math.floor(mp.get_property_native('duration') or 0) then return end	

	local width = mp.get_property_native("osd-width")
	local height = mp.get_property_native("osd-height")
	mp.set_property_native("geometry", ("%dx%d"):format(width, height))
	
	mp.command(
		"no-osd af add @skiptosilence:lavfi=[silencedetect=noise=" ..
		o.silence_audio_level .. "dB:d=" .. o.silence_duration .. "]"
	)

	mp.observe_property("af-metadata/skiptosilence", "string", foundSilence)

	sub_state = mp.get_property("sub-visibility")
	mp.set_property("sub-visibility", "no")
	secondary_sub_state = mp.get_property("secondary-sub-visibility")
	mp.set_property("secondary-sub-visibility", "no")
	window_state = mp.get_property("force-window")
	mp.set_property("force-window", "yes")
	vid_state = mp.get_property("vid")
	mp.set_property("vid", "no")
	mute_state = mp.get_property_native("mute")
    if o.force_mute_on_skip then
        mp.set_property_bool("mute", true)
    end
	pause_state = mp.get_property_native("pause")
	mp.set_property_bool("pause", false)
	speed_state = mp.get_property_native("speed")
	mp.set_property("speed", 100)
	skip_flag = true
	
	timer = mp.add_periodic_timer(0.5, function()
		local video_time = (mp.get_property_native("time-pos") or 0)
		handleMinMaxDuration(video_time)
	end)
end

function foundSilence(name, value)
	if value == "{}" or value == nil then
		return
	end
	
	timecode = tonumber(string.match(value, "%d+%.?%d+"))
	if timecode == nil or timecode < initial_skip_time + o.ignore_silence_duration then
		return
	end
	
	if handleMinMaxDuration(timecode) then return end
	
	restoreProp(timecode)

	mp.add_timeout(0.05, skippedMessage)
	skip_flag = false
end

mp.observe_property('pause', 'bool', function(name, value)
	if value and skip_flag then
		restoreProp(initial_skip_time, true)
	end
end)


mp.add_hook('on_unload', 9, function()
	if skip_flag then
		restoreProp()
	end
end)

mp.add_key_binding("F3", "skip-to-silence", doSkip)