wifi-tally_Oostendam/nodemcu-firmware/lua_examples/pcm/play_network.lua

153 lines
3.0 KiB
Lua
Raw Normal View History

2021-09-27 19:52:27 +00:00
-- ****************************************************************************
-- Network streaming example
--
-- stream = require("play_network")
-- stream.init(pin)
-- stream.play(pcm.RATE_8K, ip, port, "/jump_8k.u8", function () print("stream finished") end)
--
-- Playback can be stopped with stream.stop().
-- And resources are free'd with stream.close().
--
local M, module = {}, ...
_G[module] = M
local _conn
local _drv
local _buf
local _lower_thresh = 2
local _upper_thresh = 5
local _play_cb
-- ****************************************************************************
-- PCM
local function stop_stream(cb)
_drv:stop()
if _conn then
_conn:close()
_conn = nil
end
_buf = nil
if cb then cb()
elseif _play_cb then _play_cb()
end
_play_cb = nil
end
local function cb_drained()
print("drained "..node.heap())
stop_stream()
end
local function cb_data()
if #_buf > 0 then
local data = table.remove(_buf, 1)
if #_buf <= _lower_thresh then
-- unthrottle server to get further data into the buffer
_conn:unhold()
end
return data
end
end
local _rate
local function start_play()
print("starting playback")
-- start playback
_drv:play(_rate)
end
-- ****************************************************************************
-- Networking functions
--
local _skip_headers
local _chunk
local _buffering
local function data_received(c, data)
if _skip_headers then
-- simple logic to filter the HTTP headers
_chunk = _chunk..data
local i, j = string.find(_chunk, '\r\n\r\n')
if i then
_skip_headers = false
data = string.sub(_chunk, j+1, -1)
_chunk = nil
end
end
if not _skip_headers then
_buf[#_buf+1] = data
if #_buf > _upper_thresh then
-- throttle server to avoid buffer overrun
c:hold()
if _buffering then
-- buffer got filled, start playback
start_play()
_buffering = false
end
end
end
end
local function cb_disconnected()
if _buffering then
-- trigger playback when disconnected but we're still buffering
start_play()
_buffering = false
end
end
local _path
local function cb_connected(c)
c:send("GET ".._path.." HTTP/1.0\r\nHost: iot.nix.nix\r\n".."Connection: close\r\nAccept: /\r\n\r\n")
_path = nil
end
function M.play(rate, ip, port, path, cb)
_skip_headers = true
_chunk = ""
_buffering = true
_buf = {}
_rate = rate
_path = path
_play_cb = cb
_conn = net.createConnection(net.TCP, 0)
_conn:on("receive", data_received)
_conn:on("disconnection", cb_disconnected)
_conn:connect(port, ip, cb_connected)
end
function M.stop(cb)
stop_stream(cb)
end
function M.init(pin)
_drv = pcm.new(pcm.SD, pin)
-- get called back when all samples were read from stream
_drv:on("drained", cb_drained)
_drv:on("data", cb_data)
--_drv:on("stopped", cb_stopped)
end
function M.vu(cb, freq)
_drv:on("vu", cb, freq)
end
function M.close()
stop_stream()
_drv:close()
_drv = nil
end
return M