[PD] Seamless recording of 2 consecutive audio files?

[Florian Hollerweger]

Hi everybody,

Is it possible to record 2 audio files with [writesf~] in a manner that
the second starts "exactly after" the first one stops? In other words so
that there will be a seamless (click-free) transisition when glueing the
two together.

Peter Plessas and I have tried this with the attached patch, expecting
to get either a perfect transition, _or_ to run late by exactly one
block of audio (in our case 64 samples). But instead it seems that we
run somewhere between 15 and 20 samples late (after glueing them
together in CoolEdit and through visual inspection).

Any hints on what's going on behind the scenes would be appreciated.

best,
flo.H



#N canvas 501 25 549 270 10;
#X msg 65 48 start;
#X msg 137 136 stop;
#X obj 65 -10 t b b;
#X obj 65 -44 bng 15 250 50 0 empty empty empty 17 7 0 10 -262144 -1
-1;
#X obj 432 -21 loadbang;
#X msg 432 21 \; pd dsp 1;
#X obj 12 129 osc~ 220;
#X msg 207 114 start;
#X obj 166 82 bng 15 250 50 0 empty empty empty 17 7 0 10 -262144 -1
-1;
#X msg 292 149 stop;
#X obj 107 181 writesf~;
#X obj 204 181 writesf~;
#X text 85 -47 1) open both files and start first recording;
#X text 189 82 2) stop first and start second recording;
#X text 335 150 3) stop second recording;
#X msg 107 19 open test1.wav;
#X msg 279 107 open test2.wav;
#X connect 0 0 10 0;
#X connect 1 0 10 0;
#X connect 2 0 0 0;
#X connect 2 1 15 0;
#X connect 2 1 16 0;
#X connect 3 0 2 0;
#X connect 4 0 5 0;
#X connect 6 0 10 0;
#X connect 6 0 11 0;
#X connect 7 0 11 0;
#X connect 8 0 7 0;
#X connect 8 0 1 0;
#X connect 9 0 11 0;
#X connect 15 0 10 0;
#X connect 16 0 11 0;