The Video Processing System part 4
I've got a question to the experienced jitter users. i am just reading the part 4 of the "The Video Processing System" tutorial. in the subpatch for the poly~ abstraction building the video-player i find the the message-box with the loadram messages. According to the tutorial description the author intents to load the "first and last 2 seconds" of the movie into RAM (asuming a timescale of 600).
I do understand that for the second loadram message, but shouldn'1 have the first one also two arguments (in this case "loadram 0 1200" instead of (loadram 1200)?
i understand the reference in that way that loadram with one argument specifies the track to be loaded.
Thanks for all answers.
Best Jan
jit.qt.movie reference:
....
Two additional arguments may be used to specify start and end times for the loadram operation. So, loadram followed by 2 arguments will load a specified portion of an entire movie, while loadram followed by 3 arguments will cause the jit.qt.movie to load a portion of a single track into RAM.
that what i thought as well. so its a bug in the tutorial...
You are correct. This is an error in the patch. I will update the file soon.
Best,
Andrew B.
i hope you don't get me wrong. i don't want to be picky - i was just confused and suspecting some special tricks as i am still in the process of learning jitter.
Thanks for the clarification and the of course for your tutorial - that help me quite a bit in my own work.
And as we are already speaking about corrections. (well now it's sounds really picky ) there is another point i found: I think inside the texture-conversion subpatch the right switch object should be "switch 1 2". At the moment it is "switch 2 2".
best
jan
I must add that it would be cool if we could add comments to the tutorials articles. Since it's the best place to ask questions about the patches or do debugging like this. Or maybe just create a subject in the forum and add a link to it in the tutorial.
Pierre
I have updated the tutorial patch with the appropriate change. The switch arguments are in fact correct. By default, the left switch passes input 1 and the right one, input 2. This is reflected in the respective arguments.
Thanks for spotting the error.
Andrew B.
I've been really excited by all of the VPS tutorials and was especially happy to have a patch using poly~ for movies to learn from. However, In my tests of the patch I've been having a disappointing performance issue.
I'm loading a folder of about 15 DV clips (all fairly short, 15 seconds or less) and for the first time that I cycle thru the clips there is a black flash between each one. After I have triggered every clip at least once this problem goes away. I am very confused my this and haven't the foggiest idea where to begin troubleshooting. Any clues as to what is causing this and how I might fix it would be greatly appreciated.
TIA!
Yes don't use DV clips you need to convert your video clips into a different codex. Currently the best videos for running in Jitter as my understanding is Photo - JPEG and Apple ProRes 422.
The black frames issue is addressed in this forum thread:https://cycling74.com/forums/index.php?t=msg&th=41522&start=0&rid=0&S=3dc3b83ddbead110c3eb6da5df4dec6f
Best,
Andrew B.
hi,
two questions :
why do you preload the last 2 seconds too ?
isn't it better to use @editmode 1 and enter this values as ms ?
thx.
f./