#! lua
local lanes = require "lanes".configure()
local plot = require "plotspl"
local struct = require "struct"
local rc = dofile"scared.rc"
rc.address = rc.address or "user@example.com"
rc.mode = rc.mode or "SPL"
-- today's date in (almost) ISO-8601 format
local function isodate()
return os.date"%Y-%m-%d %H:%M:%S"
end
-- today's date for use in a file name
local function namedate()
return os.date"%Y%m%d-%H%M%S"
end
-- make its argument be a single double-quoted string
function flatten(s)
if type(s)=="string" then return '"'..s..'"' end
if type(s)~="table" then return nil end
return '"'..table.concat(s, '" "')..'"'
end
-- Send an email to addr with subject and body. If body
-- is nil then just repeat the subject. This assumes that
-- a "mail" command is available with the usual options.
local function email(addr, subj, body)
body = body or subj
local mail = ("mail -s '%q' %s"):format(subj,addr)
local b = assert(io.popen(mail, "w"))
b:write([[I heard a noise on ]], isodate(), "\r\n\r\n")
b:write(body, "\r\n\r\n")
b:write"(This an automated message.)\r\n"
b:close()
end
-- Send a MIME packed email containing a file related
-- to the event to a recipient with a subject
local function mpack(address, subject, file)
assert(address)
assert(subject)
assert(file)
local cmd = ("mpack -a -s %q %q %s"):format(subject, file, address)
print(cmd)
os.execute(cmd)
end
-- Implement a buffer of samples. For simplicity, let the
-- index increment without bound. Note that this will have
-- a problem after 2^53 samples, which is about 30 million
-- years at 10 samples per second or 300 thousand years at
-- about 1000 samples per second.
local recent = {
depth=200,
n=1,
-- clear the buffer and set a new depth
clear=function(self,newdepth)
newdepth = newdepth or 200
local offset = self.n-self.depth-1
for i=1,self.depth do
self[i+offset] = nil
end
self.n = 1
self.depth = newdepth
end,
-- add a sample to the buffer
add=function(self,spl)
local n = self.n
self[n] = spl
self[n-self.depth] = nil
self.n = n + 1
end,
-- return the entire buffer as a raw blob
raw=function(self)
return table.concat(self,'',self.n-self.depth,self.n-1)
end,
-- return a CSV formatted buffer assuming the samples
-- are SPL levels at 10 Hz
CSVtext=function(self, header)
local t = header and {"s, dB"} or {}
local offset = self.n-self.depth-1
for i=1,self.depth do
if self[i+offset] then
t[#t+1] = ("%0.1f, %s"):format(i/10,self[i+offset])
end
end
return table.concat(t,"\n")
end
}
local function auheader(buf, rate)
local fmt = ">c4LLLLLL"
local hdr = struct.pack(fmt,
".snd", -- 0 magic number
struct.size(fmt), -- 1 data offset
#buf, -- 2 length or -1
1, -- 3 encoding uLaw
rate, -- 4 8152 Hz sample rate
1, -- 5 mono
0) -- 6 empty metadata string
return hdr
end
local function writeau(au, buf)
local f = assert(io.open(au,"wb"))
f:write(auheader(buf, 8152), buf)
f:close()
end
function writemp3(name, udata)
local soxgate = 'compand .1,.2 -inf,-55.1,-inf,-55,-55 0 -90 .1 '
local soxcompand = 'compand 0.3,1 6:-70,-60,-20 -5 -90 0.2 '
local soxcmd = 'sox -t au - -t wav -b 16 - '
.. soxgate
.. soxcompand
..'| lame - '..name
print(soxcmd)
local fp = assert(io.popen('sh -c "'..soxcmd..'"', 'w'))
fp:write(auheader(udata, 8000), udata)
fp:close()
end
-- Quick and dirty way to force the UART to have the
-- tty driver settings we need for clean raw access
-- to the port.
os.execute("stty -F /dev/ttyAMA0 115200"
.." pass8 raw -iexten"
.." -echo -echoe -echok -echoke -echoctl")
-- Open the UART for both reading and writing, and send
-- the SPLear command to go into raw SPL sample mode. The
-- output must be unbuffered because the current SPLear
-- firmware would revert to 0.5 Hz summary mode if it
-- receives a newline.
local port = assert(io.open('/dev/ttyAMA0','r+'))
port:setvbuf"no" -- no output buffer at all
local addr = flatten(rc.address)
print("Notifying "..addr)
-- command the requested mode
if rc.mode == "record" then
port:write"R" -- so this write is immediate
local msgs = lanes.linda()
-- temporary simulation of noises by 10 second timer
lanes.timer(msgs, "tick", 10, 10)
-- Function running in a separate thread that watches for loud
-- noises signled via GPIO pin
pinwatcher = lanes.gen("*", function()
gpio = require "sysfsgpio"
gpio.export(7)
gpio.direction(7, "in")
gpio.edge(7, "rising")
print("Watching GPIO07 which is pin P1-26")
while true do
--local _, t = msgs:receive"tick" -- external simulation timer
local r = gpio.wait(7)
if r == 0 then
-- poll timed out
elseif r == 1 then
msgs:send("eek", isodate())
else
-- something unexpected happened
end
end
end
)()
-- main loop reads data as usual, keeping an eye out for
-- being scared, after which it saves and emails a recording.
local triggered = false
local eek
while true do
local sample = port:read(800) -- read 1/10 sec audio
if sample then
io.write("Rec "..(triggered and "TRG " or " "), recent.n, "\r")
io.flush()
recent:add(sample)
-- Notice GPIO pin
local s = pinwatcher.status
if not (s == "waiting" or s == "running" or s == "pending") then
print("Watcher status: "..s)
break
end
local eekflag, eekval = msgs:receive(0.0, "eek")
if eekflag then
if not triggered then
triggered = math.floor(recent.depth * 2. / 3.)
eek = "EEK! "..eekval
end
end
if triggered then
triggered = triggered - 1
if triggered == 0 then
triggered = false
local data = recent:raw(false)
local mp3file = "eek-"..namedate()..".mp3"
writemp3(mp3file, data)
print("email " .. addr, mp3file, isodate())
mpack(addr, eek, mp3file)
end
end
spl0 = spl
end
end
else -- mode == "SPL"
port:write"S" -- so this write is immediate
-- Loop reading the SPL samples and watching for loud
-- noises, keeping a log of recent samples as we go.
-- When a loud noise is heard, keep logging for a bit
-- before sending email. Include the log in the email.
local spl, spl0
local triggered = false
local eek = ""
while true do
local line = port:read"*l" -- read a single line
spl = tonumber(line)
if spl then
spl = 0.75 * spl
io.write("SPL "..(triggered and "TRG " or " "), spl, "\r")
recent:add(spl)
-- Watch for the trigger condition: 12 dB louder
if not triggered and spl0 and (spl - spl0 > 12.) then
triggered = math.floor(recent.depth * 2. / 3.)
eek = "EEK! "..spl.." dB"
end
if triggered then
triggered = triggered - 1
if triggered == 0 then
triggered = false
local data = recent:CSVtext(false)
local pngfile = "tmp-SPL.png"
plot.plot(data,
pngfile,
recent.depth/30., -- 1/3 trigger pos, 1/10 for time scale
"Startled at "..isodate())
local body = eek.."\n"..data
print("email " .. addr, eek, isodate())
mpack(addr, eek, pngfile)
end
end
spl0 = spl
end
end
end
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