what happens in a block cycle?
first all dsp computation is done, then all new messaging is handled:
usually 64 samples of digital (audio) signal are blocked together. so lets say you have a line~ object that received a message [0, 1 10( before the new block started. so that is executed beginning with the first sample of the block cycle. lets say the line~ is directly connected to an [dac~] object. so there is a buffer of 64 samples and the first of these samples is filled with 0. then (still dsp computations...) the next value of line is calculated, which will be dependend on the sample rate settings (let's say 44.1k) so 1 sample is 1/44.1 ms, which will give the next rampvalue of 0.00227 (you will reach "1" after 441 samples). in this way 64 samples are written to the buffer. 0, 0.00454, 0.00680... during all these calculations no new messages are handled. [v messages have a slightly different behaviour here] finally (that is varying depending on the sound card driver and operating system you are using) this buffer goes to the soundcard. THEN: after all that dsp stuff is done, the messaging process is turned on. interface events (even if they are received and saved during dsp computation) will only have effect for the beginning of the next block. the whole messaging process will set a lot of new values that will interact with the next dsp computations. for example our line object might receive new values...
does this all make sense? smaller blocksizes give you the possibility to handle messages in even shorter time intervals, bigger blocksizes may help to declick for example when you write to arrays. [for some objects blocksize is even more important (fft~, tabsend~).]
marius.
Steffen wrote:
I understand that decreasing the block size will possible requirer
more computation/logical time then there is real time enough to
complete. And therefore that the information in a block is available
to the program to process. Which also means that after that block has
been processes the information is not longer available. Is that true?
What is a block, what's in it, what properties does it have. Is a
block a sample or is a block made out of a number (being the block
size) of samples? And also Jamie's question: what does the 'v' stand
for?I suspect there is some digital music fundamentals that I'm lacking.
Thanks for your patients, all of you.
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