sc3-rom-dump/rom/programs/fun/speaker.lua

137 lines
4.2 KiB
Lua

-- SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
--
-- SPDX-License-Identifier: MPL-2.0
local function get_speakers(name)
if name then
local speaker = peripheral.wrap(name)
if speaker == nil then
error(("Speaker %q does not exist"):format(name), 0)
return
elseif not peripheral.hasType(name, "speaker") then
error(("%q is not a speaker"):format(name), 0)
end
return { speaker }
else
local speakers = { peripheral.find("speaker") }
if #speakers == 0 then
error("No speakers attached", 0)
end
return speakers
end
end
local function pcm_decoder(chunk)
local buffer = {}
for i = 1, #chunk do
buffer[i] = chunk:byte(i) - 128
end
return buffer
end
local function report_invalid_format(format)
printError(("speaker cannot play %s files."):format(format))
local pp = require "cc.pretty"
pp.print("Run '" .. pp.text("help speaker", colours.lightGrey) .. "' for information on supported formats.")
end
local cmd = ...
if cmd == "stop" then
local _, name = ...
for _, speaker in pairs(get_speakers(name)) do speaker.stop() end
elseif cmd == "play" then
local _, file, name = ...
local speaker = get_speakers(name)[1]
local handle, err
if http and file:match("^https?://") then
print("Downloading...")
handle, err = http.get(file)
else
handle, err = fs.open(file, "r")
end
if not handle then
printError("Could not play audio:")
error(err, 0)
end
local start = handle.read(4)
local pcm = false
local size = 16 * 1024 - 4
if start == "RIFF" then
handle.read(4)
if handle.read(8) ~= "WAVEfmt " then
handle.close()
error("Could not play audio: Unsupported WAV file", 0)
end
local fmtsize = ("<I4"):unpack(handle.read(4))
local fmt = handle.read(fmtsize)
local format, channels, rate, _, _, bits = ("<I2I2I4I4I2I2"):unpack(fmt)
if not ((format == 1 and bits == 8) or (format == 0xFFFE and bits == 1)) then
handle.close()
error("Could not play audio: Unsupported WAV file", 0)
end
if channels ~= 1 or rate ~= 48000 then
print("Warning: Only 48 kHz mono WAV files are supported. This file may not play correctly.")
end
if format == 0xFFFE then
local guid = fmt:sub(25)
if guid ~= "\x3A\xC1\xFA\x38\x81\x1D\x43\x61\xA4\x0D\xCE\x53\xCA\x60\x7C\xD1" then -- DFPWM format GUID
handle.close()
error("Could not play audio: Unsupported WAV file", 0)
end
size = size + 4
else
pcm = true
size = 16 * 1024 * 8
end
repeat
local chunk = handle.read(4)
if chunk == nil then
handle.close()
error("Could not play audio: Invalid WAV file", 0)
elseif chunk ~= "data" then -- Ignore extra chunks
local size = ("<I4"):unpack(handle.read(4))
handle.read(size)
end
until chunk == "data"
handle.read(4)
start = nil
-- Detect several other common audio files.
elseif start == "OggS" then return report_invalid_format("Ogg")
elseif start == "fLaC" then return report_invalid_format("FLAC")
elseif start:sub(1, 3) == "ID3" then return report_invalid_format("MP3")
elseif start == "<!DO" --[[<!DOCTYPE]] then return report_invalid_format("HTML")
end
print("Playing " .. file)
local decoder = pcm and pcm_decoder or require "cc.audio.dfpwm".make_decoder()
while true do
local chunk = handle.read(size)
if not chunk then break end
if start then
chunk, start = start .. chunk, nil
size = size + 4
end
local buffer = decoder(chunk)
while not speaker.playAudio(buffer) do
os.pullEvent("speaker_audio_empty")
end
end
handle.close()
else
local programName = arg[0] or fs.getName(shell.getRunningProgram())
print("Usage:")
print(programName .. " play <file or url> [speaker]")
print(programName .. " stop [speaker]")
end