Jennek Geels

I am working on a project where we want to record live video at 

720p25 with a blackmagic Intensity card into a jit.matrixset.

we want to record over 10 minutes and scrub thru the frames as they 

This will be a mac pro with at least 16Gb.

before actually buying the equipment needed, I would like to find out 

- will the intensity card be able to grab at 25fps minimum (using 

all the video processing will be done on the GPU so there is very 

- does a jitmatrixset of over 6 Gb actually work? are there no hard 

I realise that this is quite extreme, but maybe some of you have 

I am working on a project where we want to record live video at  
720p25 with a blackmagic Intensity card into a jit.matrixset.
we want to record over 10 minutes and scrub thru the frames as they  
come in.
This will be a mac pro with at least 16Gb.

before actually buying the equipment needed, I would like to find out  
if this has any chance of succeeding.
In particular:
- will the intensity card be able to grab at 25fps minimum (using  
jit.qt.grab)?
   all the video processing will be done on the GPU so there is very  
little CPU activity going on.
- does a jitmatrixset of over 6 Gb actually work? are there no hard  
wired limits inside?

I realise that this is quite extreme, but maybe some of you have  
tried this.
thanks,
-jennek


jit-matrixset-6-gb-intensity-25fps

On Fri, Aug 1, 2008 at 1:02 PM, jennek geels wrote:

> I am working on a project where we want to record live video at 720p25 with

> a blackmagic Intensity card into a jit.matrixset.

> we want to record over 10 minutes and scrub thru the frames as they come in.

> This will be a mac pro with at least 16Gb.

> before actually buying the equipment needed, I would like to find out if

> - will the intensity card be able to grab at 25fps minimum (using

> all the video processing will be done on the GPU so there is very little

> - does a jitmatrixset of over 6 Gb actually work? are there no hard wired

RAM is an issue. Jitter has a 32bit address space which if I remember

On Fri, Aug 1, 2008 at 1:02 PM, jennek geels  wrote:
> Hi,
>
> I am working on a project where we want to record live video at 720p25 with
> a blackmagic Intensity card into a jit.matrixset.
> we want to record over 10 minutes and scrub thru the frames as they come in.
> This will be a mac pro with at least 16Gb.
>
> before actually buying the equipment needed, I would like to find out if
> this has any chance of succeeding.
> In particular:
> - will the intensity card be able to grab at 25fps minimum (using
> jit.qt.grab)?
>  all the video processing will be done on the GPU so there is very little
> CPU activity going on.

> - does a jitmatrixset of over 6 Gb actually work? are there no hard wired
> limits inside?

RAM is an issue.  Jitter has a 32bit address space which if I remember
correctly means a max 2GB limit.

On 1-aug-2008, at 22:12, Wesley Smith wrote:

> On Fri, Aug 1, 2008 at 1:02 PM, jennek geels 

>> I am working on a project where we want to record live video at 

>> a blackmagic Intensity card into a jit.matrixset.

>> we want to record over 10 minutes and scrub thru the frames as 

>> This will be a mac pro with at least 16Gb.

>> before actually buying the equipment needed, I would like to find 

>> - will the intensity card be able to grab at 25fps minimum (using

>> all the video processing will be done on the GPU so there is very 

>> - does a jitmatrixset of over 6 Gb actually work? are there no 

> RAM is an issue. Jitter has a 32bit address space which if I remember

would that upper limit apply to all max/jitter objects combined, or 

(in which case I could just use more than one instance)

> On Fri, Aug 1, 2008 at 1:02 PM, jennek geels  
>  wrote:
>> Hi,
>>
>> I am working on a project where we want to record live video at  
>> 720p25 with
>> a blackmagic Intensity card into a jit.matrixset.
>> we want to record over 10 minutes and scrub thru the frames as  
>> they come in.
>> This will be a mac pro with at least 16Gb.
>>
>> before actually buying the equipment needed, I would like to find  
>> out if
>> this has any chance of succeeding.
>> In particular:
>> - will the intensity card be able to grab at 25fps minimum (using
>> jit.qt.grab)?
>>  all the video processing will be done on the GPU so there is very  
>> little
>> CPU activity going on.
>
>
>> - does a jitmatrixset of over 6 Gb actually work? are there no  
>> hard wired
>> limits inside?
>
> RAM is an issue.  Jitter has a 32bit address space which if I remember
> correctly means a max 2GB limit.
>
> wes

would that upper limit apply to all max/jitter objects combined, or  
to one matrixset instance
(in which case I could just use more than one instance)

Live video capture -> Effects on GPU using GL -> GL buffer capture - 

I am working with macpros with 16gb of ram , and I can tell that 

they will easily record to 720p30 when doing regular DV capture (cant 

capture HD, dont have the hardware) , using jit.qt.grab to do the 

capture, jit.gl.asyncread to capture the gl buffer and 

jit.qt.record to record to disk (with the actual renderer still 

On 1-Aug-08, at 4:02 PM, jennek geels wrote:

> I am working on a project where we want to record live video at 

> 720p25 with a blackmagic Intensity card into a jit.matrixset.

> we want to record over 10 minutes and scrub thru the frames as they 

> before actually buying the equipment needed, I would like to find 

> out if this has any chance of succeeding.

> - will the intensity card be able to grab at 25fps minimum (using 

> all the video processing will be done on the GPU so there is very 

> - does a jitmatrixset of over 6 Gb actually work? are there no hard 

> I realise that this is quite extreme, but maybe some of you have 

Live video  capture -> Effects on GPU using GL -> GL buffer capture - 
 > capture to disk

I am working with  macpros with 16gb of ram , and I can tell that  
they will easily record to 720p30 when doing regular DV capture (cant  
capture HD, dont have the hardware) , using jit.qt.grab to do the  
capture,  jit.gl.asyncread to capture the  gl buffer and  
jit.qt.record  to record to disk (with the actual renderer still  
going at 44 fps).

> Hi,
>
> I am working on a project where we want to record live video at  
> 720p25 with a blackmagic Intensity card into a jit.matrixset.
> we want to record over 10 minutes and scrub thru the frames as they  
> come in.
> This will be a mac pro with at least 16Gb.
>
> before actually buying the equipment needed, I would like to find  
> out if this has any chance of succeeding.
> In particular:
> - will the intensity card be able to grab at 25fps minimum (using  
> jit.qt.grab)?
>   all the video processing will be done on the GPU so there is very  
> little CPU activity going on.
> - does a jitmatrixset of over 6 Gb actually work? are there no hard  
> wired limits inside?
>
> I realise that this is quite extreme, but maybe some of you have  
> tried this.
> thanks,
> -jennek


I'm also curious how much will 16GB system be able to allocate.

But since there is at least 4gb limit(32bits), one solution would be 

to distribute the whole system on several 'memory bank' patches, 

simultaneously run in separate max(runtime) processes. They could then 

But since there is at least 4gb limit(32bits), one solution would be  
to distribute the whole system on several 'memory bank' patches,  
simultaneously run in separate max(runtime) processes. They could then  
communicate with the jit.net objects.

very late that I come about this thread, but for the sake of completeness:

the easiest way to record as much video as you have RAM left over, is to make a RAM disk. This is a disk in RAM. And you have several free utilities to make them. Just do it before starting MAX and you can assing this disk as a destination to do (really fast) storage.

The only thing with a RAM disk is: it looses its content when the computer shuts off. So save out of there before shutting down.

Also leave enough RAM for your system (at least 2Gb) otherwise it becomes very slow.

very late that I come about this thread, but for the sake of completeness:
the easiest way to record as much video as you have RAM left over, is to make a RAM disk. This is a disk in RAM. And you have several free utilities to make them. Just do it before starting MAX and you can assing this disk as a destination to do (really fast) storage. 

jit.matrixset: >6 GB? Intensity: >25fps?