mpv/TOOLS/lua/acompressor.lua

159 lines
4.3 KiB
Lua

-- This script adds control to the dynamic range compression ffmpeg
-- filter including key bindings for adjusting parameters.
--
-- See https://ffmpeg.org/ffmpeg-filters.html#acompressor for explanation
-- of the parameters.
local mp = require 'mp'
local options = require 'mp.options'
local o = {
default_enable = false,
show_osd = true,
osd_timeout = 4000,
filter_label = mp.get_script_name(),
key_toggle = 'n',
key_increase_threshold = 'F1',
key_decrease_threshold = 'Shift+F1',
key_increase_ratio = 'F2',
key_decrease_ratio = 'Shift+F2',
key_increase_knee = 'F3',
key_decrease_knee = 'Shift+F3',
key_increase_makeup = 'F4',
key_decrease_makeup = 'Shift+F4',
key_increase_attack = 'F5',
key_decrease_attack = 'Shift+F5',
key_increase_release = 'F6',
key_decrease_release = 'Shift+F6',
default_threshold = -25.0,
default_ratio = 3.0,
default_knee = 2.0,
default_makeup = 8.0,
default_attack = 20.0,
default_release = 250.0,
step_threshold = -2.5,
step_ratio = 1.0,
step_knee = 1.0,
step_makeup = 1.0,
step_attack = 10.0,
step_release = 10.0,
}
options.read_options(o)
local params = {
{ name = 'attack', min=0.01, max=2000, hide_default=true, dB='' },
{ name = 'release', min=0.01, max=9000, hide_default=true, dB='' },
{ name = 'threshold', min= -30, max= 0, hide_default=false, dB='dB' },
{ name = 'ratio', min= 1, max= 20, hide_default=false, dB='' },
{ name = 'knee', min= 1, max= 10, hide_default=true, dB='dB' },
{ name = 'makeup', min= 0, max= 24, hide_default=false, dB='dB' },
}
local function parse_value(value)
-- Using nil here because tonumber differs between lua 5.1 and 5.2 when
-- parsing fractions in combination with explicit base argument set to 10.
-- And we can't omit it because gsub returns 2 values which would get
-- unpacked and cause more problems. Gotta love scripting languages.
return tonumber(value:gsub('dB$', ''), nil)
end
local function format_value(value, dB)
return string.format('%g%s', value, dB)
end
local function show_osd(filter)
if not o.show_osd then
return
end
if not filter.enabled then
mp.commandv('show-text', 'Dynamic range compressor: disabled', o.osd_timeout)
return
end
local pretty = {}
for _,param in ipairs(params) do
local value = parse_value(filter.params[param.name])
if not (param.hide_default and value == o['default_' .. param.name]) then
pretty[#pretty+1] = string.format('%s: %g%s', param.name:gsub("^%l", string.upper),
value, param.dB)
end
end
if #pretty == 0 then
pretty = ''
else
pretty = '\n(' .. table.concat(pretty, ', ') .. ')'
end
mp.commandv('show-text', 'Dynamic range compressor: enabled' .. pretty, o.osd_timeout)
end
local function get_filter()
local af = mp.get_property_native('af', {})
for i = 1, #af do
if af[i].label == o.filter_label then
return af, i
end
end
af[#af+1] = {
name = 'acompressor',
label = o.filter_label,
enabled = false,
params = {},
}
for _,param in pairs(params) do
af[#af].params[param.name] = format_value(o['default_' .. param.name], param.dB)
end
return af, #af
end
local function toggle_acompressor()
local af, i = get_filter()
af[i].enabled = not af[i].enabled
mp.set_property_native('af', af)
show_osd(af[i])
end
local function update_param(name, increment)
for _,param in pairs(params) do
if param.name == string.lower(name) then
local af, i = get_filter()
local value = parse_value(af[i].params[param.name])
value = math.max(param.min, math.min(value + increment, param.max))
af[i].params[param.name] = format_value(value, param.dB)
af[i].enabled = true
mp.set_property_native('af', af)
show_osd(af[i])
return
end
end
mp.msg.error('Unknown parameter "' .. name .. '"')
end
mp.add_key_binding(o.key_toggle, "toggle-acompressor", toggle_acompressor)
mp.register_script_message('update-param', update_param)
for _,param in pairs(params) do
for direction,step in pairs({increase=1, decrease=-1}) do
mp.add_key_binding(o['key_' .. direction .. '_' .. param.name],
'acompressor-' .. direction .. '-' .. param.name,
function() update_param(param.name, step*o['step_' .. param.name]); end,
{ repeatable = true })
end
end
if o.default_enable then
local af, i = get_filter()
af[i].enabled = true
mp.set_property_native('af', af)
end