Daniel Beck

I'm new to Jitter but have been working with Max for a while. I'm stuck on what I'm guessing is a simple one to answer hopefully - I'm using jit.gl.asyncread to output to Syphonserver from a modified version of Asteroid Growths which is a part of the Jitter Recipes set of patches.

I'm looking to make a set of different videos synced to the stems of an audio track - I have a 1920x1080 jit.window which is behaving exactly as I want it to... the problem is that asyncread is outputting at 1920x1080 but with just the bottom-left quarter of the image. Is there a simple scale function that I'm missing that will get what I'm seeing in my jit.window to output at the correct size?

Here's the patch with it's modifications...

jit.gl.asyncread

jit.gl.syphonserver

message

comment

button

prepend

flonum

dial

pack

toggle

metro

bgcolor

jit.xfade

jit.matrix

sfplay~

rand~

sig~

inlet

peakamp~

jit.poke~

ezdac~

umenu

jit.gl.isosurf

keyup

qmetro

jit.window

jit.gl.handle

jit.gl.render

counter

jit.pwindow

panel

I'm new to Jitter but have been working with Max for a while. I'm stuck on what I'm guessing is a simple one to answer hopefully - I'm using jit.gl.asyncread to output to Syphonserver from a modified version of Asteroid Growths which is a part of the Jitter Recipes set of patches. 

Here's the patch with it's modifications...


I'm new to Jitter but have been working with Max for a while. I'm stuck on what I'm guessing is a simple one to answer hopefully - I'm using

scaling-issue-using-asyncread-and-syphoneserver

Syphon is not intended to be used with jit.gl.asyncread.

Syphon's main purposes is to share textures stored on the GPU's memory between applications.

Jit.gl.asyncread reads and converts textures stored on the GPU memory (VRAM) to main memory (RAM), to be used by the CPU, usually to encode and record a file to disk.

Use jit.gl.node in @capture 1 mode instead (see the Help File), and send the captured texture to the Syphon object.

Syphon is not intended to be used with jit.gl.asyncread.
Syphon's main purposes is to share textures stored on the GPU's memory between applications.
Jit.gl.asyncread reads and converts textures stored on the GPU memory (VRAM) to main memory (RAM), to be used by the CPU, usually to encode and record a file to disk.

Thanks for your suggestion Pedro and for the info on asyncread. I've taken a good look at jit.gl.node and its help and reference file and after a fair bit of trial and error, including using a copy of the simple example in the help file as a test project. I've not been able to get it to output to Syphon.

I found myself using jit.gl.asyncread with Syphon because of a reply on a forum post on this site that suggested that this was a possible way to record the contents of a jit.window to a file without using screen recording software. Do you think that this is completely out of the question?

asyncread's function of converting textures from GPU to RAM for recording doesn't feel like a process that's a long way off what I'm looking to achieve (record the output of a jit.window to a file) but I understand that Syphon might not be best the way to achieve this. It is however, very close to working exactly how I want it to, just with this issue of the full image appearing in the bottom left quarter of the frame in Syphon.

Thanks for your suggestion Pedro and for the info on asyncread. I've taken a good look at jit.gl.node and its help and reference file and after a fair bit of trial and error, including using a copy of the simple example in the help file as a test project. I've not been able to get it to output to Syphon. 

Render your content to texture using [jit.gl.node]. Send this texture to the SyphonRecorder app via... well.. via Syphon. It's a robust technique, probably one of the best methods to make videos from Jitter visuals in realtime.

You wrote that you want to output to Syphon but didn't mention the purpose. It all depends.

Converting textures on the GPU to CPU/RAM is a "slow" process that should be avoided wherever possible.

Even if you want to record the output of the window to a file, you shouldn't be using asyncread and Syphon together. Here's why:

- asyncread converts the window's texture (framebuffer) to a matrix (CPU),

- syphon transmits textures (GPU), so it probably converts the matrix back to texture (GPU).

- On the receiving end, the other software receives the texture and needs to convert it again to the CPU before encoding and recording to disk.

I would use jit.asyncread if I wanted to record to disk inside Max (jit.gl.asyncread / jit.record)

I would use jit.gl.node to Syphon If i wanted to record externally (the only GPU/CPU conversion would happen just one time on the other software).

You wrote that you want to output to Syphon but didn't mention the purpose. It all depends.
Converting textures on the GPU to CPU/RAM is a "slow" process that should be avoided wherever possible.

Even if you want to record the output of the window to a file, you shouldn't be using asyncread and Syphon together. Here's why:
- asyncread converts the window's texture (framebuffer) to a matrix (CPU),
- syphon transmits textures (GPU), so it probably converts the matrix back to texture (GPU).
- On the receiving end, the other software receives the texture and needs to convert it again to the CPU before encoding and recording to disk.

I would use jit.asyncread if I wanted to record to disk inside Max (jit.gl.asyncread / jit.record)
I would use jit.gl.node to Syphon If i wanted to record externally (the only GPU/CPU conversion would happen just one time on the other software).

Again Pedro - thanks very much for the information on how Syphon and async work/differ. I've not fully got my head around the correct way to use jit.g.node and Syphon to get what I want (apologies Yaniki if I'm missing something super simple here but there aren't any tutorial files I can find that are clear on how to use Syphon Recorder in this way - as I mentioned I'm a bit of Jitter novice).

With this all in mind I've gone with using jit.gl.asyncread and jit.record to write to disk from Max but I am still having my initial problem which is of asyncread scaling the image to just the bottom left corner of the recorded file.

Every time I set my dimensions to record at 1920 1080 when I click to start writing the file the dimensions are automatically doubled - I'm unable to find which setting (or even which object) is causing this to happen but I'm sure it's the reason for my issues with my image only being visible in the bottom left corner of the output file.

Now that the method is resolved - does anyone have any idea how or why my dimensions would be doubling when writing to disk?

Try with @fsaa 0 on jit.window. I seem to remember jit.gl.asyncread not supporting full scene antialising.

Scaling issue using asyncread and syphoneserver