diff options
Diffstat (limited to 'applause.lua')
| -rw-r--r-- | applause.lua | 89 |
1 files changed, 47 insertions, 42 deletions
diff --git a/applause.lua b/applause.lua index bf94d5d..5d1ba5a 100644 --- a/applause.lua +++ b/applause.lua @@ -661,26 +661,28 @@ function Stream:play(first_port) local old_stepmul = collectgarbage("setstepmul", 100) local channels = self.channels - local _, err = xpcall(self.foreach, debug.traceback, self, function(frame) - -- Loop should get unrolled automatically - for i = 1, channels do - local sample = tonumber(frame[i]) - assert(sample ~= nil) - - -- NOTE: Invalid port Ids are currently silently - -- ignored. Perhaps it's better to check state or - -- to access output_ports_count from applause.c. - local state = C.applause_push_sample(first_port+i, sample) - - -- React to buffer underruns. - -- This is done here instead of in the realtime thread - -- even though it is already overloaded, so as not to - -- affect other applications in the Jack graph. - if state == C.APPLAUSE_AUDIO_XRUN then - io.stderr:write("WARNING: Buffer underrun detected\n") + local _, err = xpcall(function() + for frame in self:iter() do + -- Loop should get unrolled automatically + for i = 1, channels do + local sample = tonumber(frame[i]) + assert(sample ~= nil) + + -- NOTE: Invalid port Ids are currently silently + -- ignored. Perhaps it's better to check state or + -- to access output_ports_count from applause.c. + local state = C.applause_push_sample(first_port+i, sample) + + -- React to buffer underruns. + -- This is done here instead of in the realtime thread + -- even though it is already overloaded, so as not to + -- affect other applications in the Jack graph. + if state == C.APPLAUSE_AUDIO_XRUN then + io.stderr:write("WARNING: Buffer underrun detected\n") + end end end - end) + end, debug.traceback) collectgarbage("setpause", old_pause) collectgarbage("setstepmul", old_stepmul) @@ -688,25 +690,26 @@ function Stream:play(first_port) if err then error(err, 0) end end ---- Execute function for each frame generated by the stream. +--- Iterator over each frame generated by the stream for use with for-in statements. -- This will process samples as fast as possible and may therefore -- not be well suited to process real-time input. --- @func fnc --- Function to execute. --- It gets passed an array of samples, one for each channel. --- If it returns true, the loop is terminated. -function Stream:foreach(fnc) +-- @treturn fnc Iterator function. +-- @usage for f in iota(10):iter() do print(f[1]) end +function Stream:iter() -- NOTE: This implementation is for single-channel streams - -- only. See also MuxStream:foreach(). + -- only. See also MuxStream:iter(). local clear = table.clear local frame = table.new(1, 0) local tick = self:gtick() - repeat + -- This could in principle use iterator state to avoid the closure, + -- but we want to bind table.clear() as well. + return function() checkint() frame[1] = tick() clear(sampleCache) - until not frame[1] or fnc(frame) + return frame[1] and frame + end end --- Benchmark stream (time to generate all samples). @@ -720,7 +723,7 @@ function Stream:benchmark() end benchmark(function() - self:foreach(function() end) + for _ in self:iter() do end end) end @@ -789,12 +792,12 @@ function Stream:totable() channel_vectors[i] = table.new(self:len(), 0) end - self:foreach(function(frame) + for frame in self:iter() do -- Loop should be unrolled automatically for i = 1, channels do channel_vectors[i][#channel_vectors[i] + 1] = frame[i] end - end) + end -- Return a list of vectors, one per channel return unpack(channel_vectors) @@ -867,10 +870,10 @@ function Stream:pipe(prog, vbufmode, vbufsize) local hnd = io.popen(prog, "w") hnd:setvbuf(vbufmode or "full", vbufsize) - self:foreach(function(frame) + for frame in self:iter() do hnd:write(unpack(frame)) hnd:write("\n") - end) + end hnd:close() end @@ -923,11 +926,11 @@ function Stream:gnuplot(file) local second = sec() local i = 1 - self:foreach(function(frame) + for frame in self:iter() do hnd:write(i/second, " ", unpack(frame)) hnd:write("\n") i = i + 1 - end) + end hnd:close() @@ -1274,14 +1277,14 @@ function MuxStream:demux(i, j) or MuxStream:new(unpack(self.streams, i, j)) end --- Overrides Stream:foreach() --- NOTE: This could easily be integrated into Stream:foreach(), +-- Overrides Stream:iter() +-- NOTE: This could easily be integrated into Stream:iter(), -- however this results in the loop to be unrolled explicitly -- for single-channel streams. -function MuxStream:foreach(fnc) +function MuxStream:iter() local clear = table.clear - local ticks = {} + local ticks = table.new(#self.streams, 0) for i = 1, #self.streams do ticks[i] = self.streams[i]:gtick() end @@ -1289,17 +1292,19 @@ function MuxStream:foreach(fnc) local channels = self.channels local frame = table.new(channels, 0) - repeat + return function() checkint() clear(sampleCache) for i = 1, channels do frame[i] = ticks[i]() -- Since all streams must have the same - -- length, if one ends all end + -- length, if one ends, all end if not frame[i] then return end end - until fnc(frame) + + return frame + end end --- Mux several streams with the source stream into a multi-channel stream. @@ -1522,7 +1527,7 @@ end function ConcatStream:gtick() local i = 1 - local ticks = {} + local ticks = table.new(#self.streams, 0) for k = 1, #self.streams do ticks[k] = self.streams[k]:gtick() |