[Csnd] Not quite understanding csounds loop function

Date	2011-11-17 13:48
From	Ole Adrian Heggli
Subject	[Csnd] Not quite understanding csounds loop function
Attachments	Looptest1.csd
	Hi, I'm new to this list, and will start off by asking for help with the loop functionality in csound. My goal is to create a script that will process files with opcodes with randomized parameters. Everything works well, apart from that my code will only actually write the audio file the second to last iteration of the for-loop. I guess this might have something to do with me not quite understanding the subleties of the csound score. Any help would be appriciated. What is considered good practise on this mailing list? Attaching files, or pasting code into the email? I wil do both for good measure. Ole Adrian Heggli MA student, SARC Queen's University Belfast -start code- ;-o ;fout.wav -W ;;; sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 instr 1 ; Creates score-events the length of the file being processed. ; Should be noted that I've tried this with an oscil-opcode in the ; looping instrument, and get the same results. So, there might be a ; flaw in this instrument, but I believe there is another flaw that ; is causing the main problems. ilength filelen "tilpros.wav" event_i "i", 2, 0, ilength endin instr 2 iindex = 1 loopStart: aInL diskin "tilpros.wav", 1 ; Read the file to be processed aInR = aInL aTestL,aTestR freeverb aInL, aInR, 0.7, 0.2 ; Processing SName sprintf "test%02d.wav", iindex ; Creates a string with changing name for each iteration fout SName,2,aTestL,aTestR ; Writes audio to disk, will only work the last iteration of the loop. ; Actually it only works the "last iteration -1" of the loop iindex = iindex + 1 if (iindex < 5) igoto loopStart endin ;f1 0 16384 10 1 i 1 0 1 i 2 0 length -end code- Send bugs reports to the Sourceforge bug tracker https://sourceforge.net/tracker/?group_id=81968&atid=564599 Discussions of bugs and features can be posted here To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"

Date	2011-11-17 14:05
From	Øyvind Brandtsegg
Subject	re: [Csnd] Not quite understanding csounds loop function
	Hello Ole I haven't looked too hard at the details, but one problem is that you loop at i-rate, but the file writing occurs at k-rate. So at init time, you rewrite the contents of SName a few times (not creating new instances), and when the k-rate processing starts it will use the last version of SName. Perhaps you could look at the udo RecursiveDiskin for inspiration http://www.csounds.com/udo/displayOpcode.php?opcode_id=8 Or perhaps it could be done with a macro. I guess using an udo would be more elegant. Oeyvind Brandtsegg Professor of Music Technology NTNU 7491 Trondheim Norway ________________________________________ Fra: Ole Adrian Heggli [oleheggli@gmail.com] Sendt: 17. november 2011 14:48 Til: csound@lists.bath.ac.uk Emne: [Csnd] Not quite understanding csounds loop function Hi, I'm new to this list, and will start off by asking for help with the loop functionality in csound. My goal is to create a script that will process files with opcodes with randomized parameters. Everything works well, apart from that my code will only actually write the audio file the second to last iteration of the for-loop. I guess this might have something to do with me not quite understanding the subleties of the csound score. Any help would be appriciated. What is considered good practise on this mailing list? Attaching files, or pasting code into the email? I wil do both for good measure. Ole Adrian Heggli MA student, SARC Queen's University Belfast -start code- ;-o ;fout.wav -W ;;; sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 instr 1 ; Creates score-events the length of the file being processed. ; Should be noted that I've tried this with an oscil-opcode in the ; looping instrument, and get the same results. So, there might be a ; flaw in this instrument, but I believe there is another flaw that ; is causing the main problems. ilength filelen "tilpros.wav" event_i "i", 2, 0, ilength endin instr 2 iindex = 1 loopStart: aInL diskin "tilpros.wav", 1 ; Read the file to be processed aInR = aInL aTestL,aTestR freeverb aInL, aInR, 0.7, 0.2 ; Processing SName sprintf "test%02d.wav", iindex ; Creates a string with changing name for each iteration fout SName,2,aTestL,aTestR ; Writes audio to disk, will only work the last iteration of the loop. ; Actually it only works the "last iteration -1" of the loop iindex = iindex + 1 if (iindex < 5) igoto loopStart endin ;f1 0 16384 10 1 i 1 0 1 i 2 0 length -end code- Send bugs reports to the Sourceforge bug tracker https://sourceforge.net/tracker/?group_id=81968&atid=564599 Discussions of bugs and features can be posted here To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound" Send bugs reports to the Sourceforge bug tracker https://sourceforge.net/tracker/?group_id=81968&atid=564599 Discussions of bugs and features can be posted here To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"

Date	2011-11-17 14:12
From	Victor Lazzarini
Subject	Re: [Csnd] Not quite understanding csounds loop function
	Hi Ole, this is because somewhere the audio signal is being overwritten before being put to the file. Generally speaking, you will not want to loop over audio signals like this. There are two ways to do what you want: 1) the simplest way is to have instr 1 spawn many instances of instr 2 (with no loops, just the audio generation opcodes) use 'out' or 'outs' etc, to write the signal to the main output buffer (which will contain the mix of all instruments). Then use the option -o to write the mixed output (instead of say -o dac) to a file. If you still want to use fout, place this in a different instrument (higher number) and then use a global variable (as a bus) or a bus channel (chnget/set etc) to send the signal from instr 2 to it 2) Use a recursive UDO to implement a loop. More complex conceptually. Victor On 17 Nov 2011, at 13:48, Ole Adrian Heggli wrote: > Hi, > > > I'm new to this list, and will start off by asking for help with the > loop functionality in csound. My goal is to create a script that will > process files with opcodes with randomized parameters. Everything > works well, apart from that my code will only actually write the audio > file the second to last iteration of the for-loop. I guess this might > have something to do with me not quite understanding the subleties of > the csound score. Any help would be appriciated. > > What is considered good practise on this mailing list? Attaching > files, or pasting code into the email? I wil do both for good measure. > > > Ole Adrian Heggli > MA student, SARC > Queen's University Belfast > > > -start code- > > > > > > ;-o ;fout.wav > -W ;;; > > > > > sr = 44100 > ksmps = 32 > nchnls = 2 > 0dbfs = 1 > > instr 1 ; Creates score-events the length of the file being processed. > ; Should be noted that I've tried this with an oscil-opcode in the > ; looping instrument, and get the same results. So, there might be a > ; flaw in this instrument, but I believe there is another flaw that > ; is causing the main problems. > > > ilength filelen "tilpros.wav" > event_i "i", 2, 0, ilength > > endin > > instr 2 > > iindex = 1 > > loopStart: > > > aInL diskin "tilpros.wav", 1 ; Read the file to be processed > aInR = aInL > aTestL,aTestR freeverb aInL, aInR, 0.7, 0.2 ; Processing > > SName sprintf "test%02d.wav", iindex ; Creates a string with changing > name for each iteration > > > fout SName,2,aTestL,aTestR ; Writes audio to disk, will only work the > last iteration of the loop. > ; Actually it only works the "last iteration -1" of the loop > > iindex = iindex + 1 > > if (iindex < 5) igoto loopStart > > > endin > > > > > > ;f1 0 16384 10 1 > i 1 0 1 > i 2 0 length > > > > > > -end code- > > Send bugs reports to the Sourceforge bug tracker > https://sourceforge.net/tracker/?group_id=81968&atid=564599 > Discussions of bugs and features can be posted here > To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound" > > Dr Victor Lazzarini Senior Lecturer Dept. of Music NUI Maynooth Ireland tel.: +353 1 708 3545 Victor dot Lazzarini AT nuim dot ie Send bugs reports to the Sourceforge bug tracker https://sourceforge.net/tracker/?group_id=81968&atid=564599 Discussions of bugs and features can be posted here To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"

Date	2011-11-18 18:23
From	Ole Adrian Heggli
Subject	Re: [Csnd] Not quite understanding csounds loop function
	Hi, Thanks for the quick replies. I will look into both possible solutions. I also came across this article (1), which seems to offering a solution to my basic problem, batch processing. (1) http://www.csounds.com/journal/issue7/commandLineFXProcessing.html Ole Adrian Heggli MA student, SARC Queen's University Belfast 2011/11/17 Victor Lazzarini : > Hi Ole, > > this is because somewhere the audio signal is being overwritten before being put to the file. > Generally speaking, you will not want to loop over audio signals like this. There are two ways > to do what you want: > > 1) the simplest way is to have instr 1 spawn many instances of instr 2 (with no loops, just the > audio generation opcodes) use 'out' or 'outs' etc, to write the signal to the main output buffer > (which will contain the mix of all instruments). Then use the option -o to write the > mixed output (instead of say -o dac) to a file. > > If you still want to use fout, place this in a different instrument (higher number) and then > use a global variable (as a bus) or a bus channel (chnget/set etc) to send the signal from instr 2 > to it > > 2) Use a recursive UDO to implement a loop. More complex conceptually. > > Victor > > On 17 Nov 2011, at 13:48, Ole Adrian Heggli wrote: > >> Hi, >> >> >> I'm new to this list, and will start off by asking for help with the >> loop functionality in csound. My goal is to create a script that will >> process files with opcodes with randomized parameters. Everything >> works well, apart from that my code will only actually write the audio >> file the second to last iteration of the for-loop. I guess this might >> have something to do with me not quite understanding the subleties of >> the csound score. Any help would be appriciated. >> >> What is considered good practise on this mailing list? Attaching >> files, or pasting code into the email? I wil do both for good measure. >> >> >> Ole Adrian Heggli >> MA student, SARC >> Queen's University Belfast >> >> >> -start code- >> >> >> >> >> >> ;-o ;fout.wav >> -W ;;; >> >> >> >> >> sr = 44100 >> ksmps = 32 >> nchnls = 2 >> 0dbfs = 1 >> >> instr 1 ; Creates score-events the length of the file being processed. >> ; Should be noted that I've tried this with an oscil-opcode in the >> ; looping instrument, and get the same results. So, there might be a >> ; flaw in this instrument, but I believe there is another flaw that >> ; is causing the main problems. >> >> >> ilength filelen "tilpros.wav" >> event_i "i", 2, 0, ilength >> >> endin >> >> instr 2 >> >> iindex = 1 >> >> loopStart: >> >> >> aInL diskin "tilpros.wav", 1 ; Read the file to be processed >> aInR = aInL >> aTestL,aTestR freeverb aInL, aInR, 0.7, 0.2 ; Processing >> >> SName sprintf "test%02d.wav", iindex ; Creates a string with changing >> name for each iteration >> >> >> fout SName,2,aTestL,aTestR ; Writes audio to disk, will only work the >> last iteration of the loop. >> ; Actually it only works the "last iteration -1" of the loop >> >> iindex = iindex + 1 >> >> if (iindex < 5) igoto loopStart >> >> >> endin >> >> >> >> >> >> ;f1 0 16384 10 1 >> i 1 0 1 >> i 2 0 length >> >> >> >> >> >> -end code- >> >> Send bugs reports to the Sourceforge bug tracker >> https://sourceforge.net/tracker/?group_id=81968&atid=564599 >> Discussions of bugs and features can be posted here >> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound" >> >> > > Dr Victor Lazzarini > Senior Lecturer > Dept. of Music > NUI Maynooth Ireland > tel.: +353 1 708 3545 > Victor dot Lazzarini AT nuim dot ie > > > > > > Send bugs reports to the Sourceforge bug tracker > https://sourceforge.net/tracker/?group_id=81968&atid=564599 > Discussions of bugs and features can be posted here > To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound" > > Send bugs reports to the Sourceforge bug tracker https://sourceforge.net/tracker/?group_id=81968&atid=564599 Discussions of bugs and features can be posted here To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"