[PD] Re: Soft Rock EP

[Claude Heiland-Allen]

Hi Paris,

Paris Treantafeles wrote:
> Hi Claude,
> 
> Thanks for the background info.
> 
> The Maciunas film is great but I think your work is sufficiently 
> different :-)
> 
> The idea of creating a customizable DVD is very cool. I can imagine 
> allowing users to control parameters in audio/video, etc. and create 
> something fun.

Yes, that's the idea, it will still be recognizably the same work, but 
(hopefully) different enough to be interesting.

> As for the steps that you took - I wonder if you could please explain 
> saving the ppm files in Gridflow.
> I have looked at
> http://gridflow.ca/latest/doc/format.html
> and just couldn't figure it out.
> I was trying to do something similar with jpegs and
> sending messages like:
> 
> [open jpeg testfile(
> 
> and
> 
> [format jpeg(
> 
> to an
> 
> [#out]
> 
> object but had no luck.
> I'm sure I'm just being stupid but any help would be appreciated!
> 
> I know that saving the files will slow things down considerably but 
> would still like to know how it's done :-)

Attached is a simple example that saves a sequence of image files to 
/tmp , I hope it helps.  The key is using:

"open <format> file <filename>"

You need the keyword "file" to distinguish from things that aren't 
files.  The keyword "gzfile" can be used instead, which will use gzip to 
compress the file.  For example, for gzip'd TGA files you can use "open 
targa gzfile blah.tga.gz" (if this doesn't work, my memory is 
flawed...).  I think other keywords are available/planned, for things 
like UDP and or TCP connections, but I've never used them.


> Thank and best,
> p


Thanks,


Claude


> 
> 
> On Aug 23, 2006, at 3:51 PM, Claude Heiland-Allen wrote:
> 
>> Paris Treantafeles wrote:
>>> Hi Claude,
>>> I finally have downloaded and watched your Soft Rock EP and wow... 
>>> great stuff!
>>> I may be biased because it's quite similar to some of my own work - 
>>> even without the GridFlow abstraction that you shared :-)
>>
>> Thanks - a friend of mine showed me a video made 40 years ago that 
>> looks similar in places:
>>
>> George Maciunas - Artype (1966), 29 mb
>> http://ubu.wfmu.org/video/fluxfilm_20_maciunas.mpg
>> http://www.ubu.com/film/fluxfilm.html
>>
>> I'll have to try harder to come up with something original!
>>
>>> If you don't mind can you tell us how you captured the visuals?
>>> They look very good - were you writing to disk (say from Gridflow to 
>>> Gem?) or sending video out to another machine to capture.
>>
>> I saved lossless ppm images direct from GridFlow.  To avoid using an 
>> excessive amount of disk space, I used a named pipe created with 
>> mkfifo to send these images directly to mpeg2enc (part of mjpegtools 
>> package, I believe).
>>
>> Needless to say it works slower than realtime, I think it rendered at 
>> about 4 frames per second on my machine, including the time taken to 
>> encode the video to MPEG2 format.
>>
>>
>> I'm working on a build system that would enable you to create your own 
>> custom Soft Rock DVD, hopefully I'll get it finished and debugged 
>> before Christmas.  It will need a fair amount of intermediate disk 
>> space (maybe 5-10 GB) because the following deadlocks after a few frames:
>>
>>        / writesf~ WAV pipe -> toolame  encoder \
>>       /                                         \
>> Pd --<                                           >-- mplex multiplexer
>>       \                                         /
>>        \ GridFlow PPM pipe -> mpeg2enc encoder /
>>
>> I believe the root cause of the deadlock is either or both of writesf~ 
>> and GridFlow using blocking I/O rather than non-blocking I/O, from 
>> what I have read mjpegtools is written to play nice with fifo's.
>>
>> The intent is to generate a sequence of unique (but similar) DVDs from 
>> around 1 MB of pd/bash/make code and a small amount of seed data.
>>
>>
>> > Thanks for sharing!
>> > p
>>
>> Thanks for the feedback!
>>
>>
>>
>> Claude
>> --http://claudiusmaximus.goto10.org
>>
>>
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