Thijs Koerselman

I'm trying to stream data from the localhost tcp to max, from another

application (c++). I tried Olaf Matthes' netsend externals, but I'm having

some trouble (could be me) and prefer to not use 3rd party externals. The

only tcp externals in max afaik are jit.net.send/recv.

If I open up a socket from my application, jit.net.recv indicates there is a

connection, but if I send something like a string or double, it doesn't

output anything. Using the same code with netreceive does give me output in

Do I have to format data in a specific way in order to be compatible with

I'm trying to stream data from the localhost tcp to max, from another
application (c++). I tried Olaf Matthes' netsend externals, but I'm having
some trouble (could be me) and prefer to not use 3rd party externals. The
only tcp externals in max afaik are jit.net.send/recv.

If I open up a socket from my application, jit.net.recv indicates there is a
connection, but if I send something like a string or double, it doesn't
output anything. Using the same code with netreceive does give me output in
max.

Do I have to format data in a specific way in order to be compatible with
jit.net.recv??

talking-to-jit-net-send-from-outside-max

I don't know how to send messages to the jit.net objects, but here's

https://cycling74.com/twiki/bin/view/ProductDocumentation/JitterSdkNetworkingSpec

I don't know how to send messages to the jit.net objects, but here's
the spec for matrices:
https://cycling74.com/twiki/bin/view/ProductDocumentation/JitterSdkNetworkingSpec

Yes, you have to format data carefully. The below link from the

Jitter SDK gives details about working with the jit.net objects.

> I'm trying to stream data from the localhost tcp to max, from another

> application (c++). I tried Olaf Matthes' netsend externals, but I'm having

> some trouble (could be me) and prefer to not use 3rd party externals. The

> only tcp externals in max afaik are jit.net.send/recv.

> If I open up a socket from my application, jit.net.recv indicates there is a

> connection, but if I send something like a string or double, it doesn't

> output anything. Using the same code with netreceive does give me output in

> Do I have to format data in a specific way in order to be compatible with

Yes, you have to format data carefully.  The below link from the
Jitter SDK gives details about working with the jit.net objects.

On 11/6/06, Thijs Koerselman  wrote:
> Hi,
>
> I'm trying to stream data from the localhost tcp to max, from another
> application (c++). I tried Olaf Matthes' netsend externals, but I'm having
> some trouble (could be me) and prefer to not use 3rd party externals. The
> only tcp externals in max afaik are jit.net.send/recv.
>
> If I open up a socket from my application, jit.net.recv indicates there is a
> connection, but if I send something like a string or double, it doesn't
> output anything. Using the same code with netreceive does give me output in
> max.
>
> Do I have to format data in a specific way in order to be compatible with
> jit.net.recv??
>
> cheers, -thijs
>
>
>
>
>


> Yes, you have to format data carefully. The below link from the

> Jitter SDK gives details about working with the jit.net objects.

Ah thanks guys! I was already looking into OSC using UDP but that involves

careful formatting too. I need to send a lot of data (100fps motion capture)

which is then processed by jitter, so I think my best bet is to format it

On 11/6/06, Ben Nevile  wrote:
>
> Hi Thijs,
>
> Yes, you have to format data carefully.  The below link from the
> Jitter SDK gives details about working with the jit.net objects.
>
>
> https://cycling74.com/twiki/bin/view/ProductDocumentation/JitterSdkNetworkingSpec

Ah thanks guys! I was already looking into OSC using UDP but that involves
careful formatting too. I need to send a lot of data (100fps motion capture)
which is then processed by jitter, so I think my best bet is to format it
into jitter matrices.

Blinkenlights is an alternative format that might be easier to use 

than Jitter matrices, and there are externals that convert the format 

to/from Jitter. However, if you suffer from tritosphobia 

(tritossymballomenomerosphobia?), as you say, then there's no point 

in plugging jit.bixcp.to/jit.bixcp.from, never mind the extended 

On 6-Nov-2006, at 21:04, Thijs Koerselman wrote:

> I need to send a lot of data (100fps motion capture) which is then 

> processed by jitter, so I think my best bet is to format it into 

Peter Castine +--> Litter Power & Litter Bundle for Jitter

Interface Building for |home | chez nous|

Max/MSP Extremely cool |bei uns | i nostri|

Blinkenlights is an alternative format that might be easier to use  
than Jitter matrices, and there are externals that convert the format  
to/from Jitter. However, if you suffer from tritosphobia  
(tritossymballomenomerosphobia?), as you say, then there's no point  
in plugging jit.bixcp.to/jit.bixcp.from, never mind the extended  
versions in Litter Bundle for Jitter.

> I need to send a lot of data (100fps motion capture) which is then  
> processed by jitter, so I think my best bet is to format it into  
> jitter matrices.

--------------    http://www.bek.no/~pcastine/Litter/    -------------
Peter Castine             +--> Litter Power & Litter Bundle for Jitter
                                Universal Binaries on the way
iCE:  Sequencing,  Recording &
       Interface  Building  for                   |home    | chez nous|
       Max/MSP   Extremely cool                   |bei uns |  i nostri|
       http://www.dspaudio.com/                   http://www.castine.de

On Nov 6, 2006, at 11:13 AM, Wesley Smith wrote:

> I don't know how to send messages to the jit.net objects,

This is almost covered by the last paragraph and the gimme_deserialize 

() code, but it's missing some crucial information. Thanks for 

First, it's missing the chunk description, which begins with a big 

endian chunk id 'JMMP', followed by a big endian 32 bit integer 

chunk size, then the data such as the gimme_deserialize() code 

expects. It's also missing the actual values of the 

ATOM_SERIALIZATION_*_CODE ids. These are single char values:

#define ATOM_SERIALIZATION_SYMBOL_CODE     's'

#define ATOM_SERIALIZATION_LONG_CODE         'l'

#define ATOM_SERIALIZATION_FLOAT_CODE     'f'

We can remedy this and and add perhaps add a gimme_serialize() 

example to the SDK documentation, but let us know if the above 

This is almost covered by the last paragraph and the gimme_deserialize 
() code, but it's missing some crucial information. Thanks for  
pointing this out.

First, it's missing the chunk description, which begins with a big  
endian chunk id  'JMMP', followed by a big endian 32 bit integer  
chunk size, then the data such as the gimme_deserialize() code  
expects. It's also missing the actual values of the  
ATOM_SERIALIZATION_*_CODE ids. These are single char values:

#define ATOM_SERIALIZATION_SYMBOL_CODE 	's'
#define ATOM_SERIALIZATION_LONG_CODE 		'l'
#define ATOM_SERIALIZATION_FLOAT_CODE 	'f'

We can remedy this and and add perhaps add a gimme_serialize()  
example to the SDK documentation, but let us know if the above  
doesn't work for you.

Here's a link to the start of a C++ class I made to send matrices into Jitter.

http://www.mat.ucsb.edu/~whsmith/Jit-Net-TCP.zip

I only spent a day on it, so it is poorly factored and a bit sloppy,

but it works and is at least easy to see what's going on so you won't

have to start from scratch. It uses BSD sockets for doing TCP.

I only spent a day on it, so it is poorly factored and a bit sloppy,
but it works and is at least easy to see what's going on so you won't
have to start from scratch.  It uses BSD sockets for doing TCP.

On Nov 6, 2006, at 2:06 PM, Joshua Kit Clayton wrote:

>> I don't know how to send messages to the jit.net objects,

> This is almost covered by the last paragraph and the 

> gimme_deserialize() code, but it's missing some crucial 

> information. Thanks for pointing this out.

Upon closer read of this doc (glanced too quickly), it looks like 

it's all covered in the packet header description at top and the last 

>> I don't know how to send messages to the jit.net objects,
>
> This is almost covered by the last paragraph and the  
> gimme_deserialize() code, but it's missing some crucial  
> information. Thanks for pointing this out.

Upon closer read of this doc (glanced too quickly), it looks like  
it's all covered in the packet header description at top and the last  
paragraph text. Sorry for the noise.

> > This is almost covered by the last paragraph and the

> > gimme_deserialize() code, but it's missing some crucial

> > information. Thanks for pointing this out.

> Upon closer read of this doc (glanced too quickly), it looks like

> it's all covered in the packet header description at top and the last

Thanks for all the help, and thanks Wes for the example! I don't expect much

trouble now. (fingers crossed). I already figured I had to define the

serialization codes myself, but since they are mentioned like you said, that

On 11/6/06, Joshua Kit Clayton  wrote:
>
>
> > This is almost covered by the last paragraph and the
> > gimme_deserialize() code, but it's missing some crucial
> > information. Thanks for pointing this out.
>
> Upon closer read of this doc (glanced too quickly), it looks like
> it's all covered in the packet header description at top and the last
> paragraph text. Sorry for the noise.

Thanks for all the help, and thanks Wes for the example! I don't expect much
trouble now. (fingers crossed). I already figured I had to define the
serialization codes myself, but since they are mentioned like you said, that
wasn't too difficult ;-)

ok, got to the point where I start hurting myself.... I took the example

Wesley posted, modified it to use winsock (cause that's what the rest of my

project is using) and cleaned it up. I cannot find anything wrong.

-no errors from the send functions, amount of bytes send is correct.

-i send the 2 headers first, than the data, everything in there seems fine.

Header sizes and content info are correct.

nothing happens in jitter, except that it tells me jit.net.recv connected,

I'm not sure how to use the recv function inside my code, or what I should

do with the latency packet, so I'm not using those right now. Can that have

If someone wants to take a look at my code I'd really appreciate it. I

-jitnet.h/cpp contains class for connecting and sending data to jitter.

ok, got to the point where I start hurting myself.... I took the example
Wesley posted, modified it to use winsock (cause that's what the rest of my
project is using) and cleaned it up. I cannot find anything wrong.

-socket is created and connected
-no errors from the send functions, amount of bytes send is correct.
-i send the 2 headers  first, than the data, everything in there seems fine.
Header sizes and content info are correct.

nothing happens in jitter, except that it tells me jit.net.recv connected,
like it should.

I'm not sure how to use the recv function inside my code, or what I should
do with the latency packet, so I'm not using those right now. Can that have
anything to do with it?

If someone wants to take a look at my code I'd really appreciate it. I
cleaned it up and think its very clear.

-exampleclient.cpp contains main program
-jitnet.h/cpp contains class for connecting and sending data to jitter.

Are you doing this work on Windows? All information needs to be sent

> ok, got to the point where I start hurting myself.... I took the example

> Wesley posted, modified it to use winsock (cause that's what the rest of my

> project is using) and cleaned it up. I cannot find anything wrong.

> -no errors from the send functions, amount of bytes send is correct.

> -i send the 2 headers first, than the data, everything in there seems fine.

> Header sizes and content info are correct.

> nothing happens in jitter, except that it tells me jit.net.recv connected,

> I'm not sure how to use the recv function inside my code, or what I should

> do with the latency packet, so I'm not using those right now. Can that have

> If someone wants to take a look at my code I'd really appreciate it. I

> cleaned it up and think its very clear.

> -exampleclient.cpp contains main program

> -jitnet.h/cpp contains class for connecting and sending data to jitter.

Are you doing this work on Windows?  All information needs to be sent
in big-endian format.

On 11/7/06, Thijs Koerselman  wrote:
> ok, got to the point where I start hurting myself.... I took the example
> Wesley posted, modified it to use winsock (cause that's what the rest of my
> project is using) and cleaned it up. I cannot find anything wrong.
>
>  -socket is created and connected
> -no errors from the send functions, amount of bytes send is correct.
> -i send the 2 headers  first, than the data, everything in there seems fine.
> Header sizes and content info are correct.
>
> nothing happens in jitter, except that it tells me jit.net.recv connected,
> like it should.
>
> I'm not sure how to use the recv function inside my code, or what I should
> do with the latency packet, so I'm not using those right now. Can that have
> anything to do with it?
>
> If someone wants to take a look at my code I'd really appreciate it. I
> cleaned it up and think its very clear.
>
>
> -exampleclient.cpp contains main program
> -jitnet.h/cpp contains class for connecting and sending data to jitter.
>
>
> cheers, -thijs
>
>
>
>
>
>
>
>
>


> Are you doing this work on Windows? All information needs to be sent

Hi Ben, that's something I haven't really thought about :-) I'll look into

it tomorrow when I get back to work. I know what it's about, but I never had

to deal with that before. thanks for pointing it out, hope that's it.

On 11/7/06, Ben Nevile  wrote:
>
> Hi Thijs,
>
> Are you doing this work on Windows?  All information needs to be sent
> in big-endian format.

Hi Ben, that's something I haven't really thought about :-) I'll look into
it tomorrow when I get back to work. I know what it's about, but I never had
to deal with that before. thanks for pointing it out, hope that's it.

So I converted my headers to big endian, using the htonl() function. Max

crashes upon sending the second (288-byte) header. Nothing is attached to

the jit.net.recv object, so this crash has to be because I'm sending invalid

Below is the function I use to create the headers. Anything wrong with it? I

also looked for a way to convert the double "time" but I can't seem to find

anything about reversing the byte order of 64bit types. Am I not supposed to

use the htonl/htons functions for byte ordering? They only support unsigned

void CJitNet :: makeMatrixHeader(int planecount, int type, int *dim, int

m_chunkHeader.id = htonl(JIT_MATRIX_PACKET_ID);

m_chunkHeader.size = htonl(sizeof(t_jit_net_packet_matrix));

m_matrixHeader.id = htonl(JIT_MATRIX_PACKET_ID);

m_matrixHeader.size = htonl(sizeof(t_jit_net_packet_matrix));

m_matrixHeader.planecount = htonl(planecount);

m_matrixHeader.dimcount = htonl(dimcount);

m_matrixHeader.dimstride[0] = htonl(typeSize * planecount);

htonl(dim[i-1]*m_matrixHeader.dimstride[i-1]);

htonl(m_matrixHeader.dimstride[dimcount-1]*m_matrixHeader.dim[dimcount-1]);

m_matrixHeader.time = 0.0; // 64bit byte order conversion??

So I converted my headers to big endian, using the htonl() function. Max
crashes upon sending the second (288-byte) header. Nothing is attached to
the jit.net.recv object, so this crash has to be because I'm sending invalid
data.

Below is the function I use to create the headers. Anything wrong with it? I
also looked for a way to convert the double "time" but I can't seem to find
anything about reversing the byte order of 64bit types. Am I not supposed to
use the htonl/htons functions for byte ordering? They only support unsigned
16 and 32 bit types(?)

void CJitNet :: makeMatrixHeader(int planecount, int type, int *dim, int
dimcount)
{
    long i;
    int typeSize;

    switch(type)
    {
        case 3:        typeSize = sizeof(double);
                    break;
        case 2:        typeSize = sizeof(float);
                    break;
        case 1:        typeSize = sizeof(long);
                    break;
        case 0:
        default:    typeSize = sizeof(char);
                    break;
    }
    m_chunkHeader.id = htonl(JIT_MATRIX_PACKET_ID);
    m_chunkHeader.size = htonl(sizeof(t_jit_net_packet_matrix));

    m_matrixHeader.id = htonl(JIT_MATRIX_PACKET_ID);
    m_matrixHeader.size = htonl(sizeof(t_jit_net_packet_matrix));
    m_matrixHeader.planecount = htonl(planecount);
    m_matrixHeader.type = htonl(type);
    m_matrixHeader.dimcount = htonl(dimcount);

    for(i=0; i < dimcount; i++) {
        m_matrixHeader.dim[i] = htonl(dim[i]);
    }

    while(i < JIT_MATRIX_MAX_DIMCOUNT) {
        m_matrixHeader.dim[i] = 0L;
        i++;
    }
    //special case for first value
    m_matrixHeader.dimstride[0] = htonl(typeSize * planecount);

    for(i=1; i
        m_matrixHeader.dimstride[i] =
htonl(dim[i-1]*m_matrixHeader.dimstride[i-1]);
    }

    while(i < JIT_MATRIX_MAX_DIMCOUNT) {
        m_matrixHeader.dimstride[i] = 0L;
        i++;
    }
    m_matrixHeader.datasize
htonl(m_matrixHeader.dimstride[dimcount-1]*m_matrixHeader.dim[dimcount-1]);
    m_matrixHeader.time = 0.0; // 64bit byte order conversion??
}

You can look at jit.byteorder.h to see how we handle byte reordering

in jitter. That header uses the below two functions:

> So I converted my headers to big endian, using the htonl() function. Max

> crashes upon sending the second (288-byte) header. Nothing is attached to

> the jit.net.recv object, so this crash has to be because I'm sending invalid

> Below is the function I use to create the headers. Anything wrong with it? I

> also looked for a way to convert the double "time" but I can't seem to find

> anything about reversing the byte order of 64bit types. Am I not supposed to

> use the htonl/htons functions for byte ordering? They only support unsigned

> void CJitNet :: makeMatrixHeader(int planecount, int type, int *dim, int

> m_chunkHeader.id = htonl(JIT_MATRIX_PACKET_ID);

> htonl(sizeof(t_jit_net_packet_matrix));

> m_matrixHeader.id = htonl(JIT_MATRIX_PACKET_ID);

> m_matrixHeader.planecount = htonl(planecount);

> m_matrixHeader.dimcount = htonl(dimcount);

You can look at jit.byteorder.h to see how we handle byte reordering
in jitter.  That header uses the below two functions:

float swapf32(float f){
	unsigned char c,*a;

	a = (unsigned char *)&f;
	c=a[3]; a[3]=a[0]; a[0]=c;
	c=a[2]; a[2]=a[1]; a[1]=c;

double swapf64(double f){
	unsigned char c,*a;

	a = (unsigned char *)&f;
	c=a[7]; a[7]=a[0]; a[0]=c;
	c=a[6]; a[6]=a[1]; a[1]=c;
	c=a[5]; a[5]=a[2]; a[2]=c;
	c=a[4]; a[4]=a[3]; a[3]=c;

On 11/8/06, Thijs Koerselman  wrote:
> So I converted my headers to big endian, using the htonl() function. Max
> crashes upon sending the second (288-byte) header. Nothing is attached to
> the jit.net.recv object, so this crash has to be because I'm sending invalid
> data.
>
> Below is the function I use to create the headers. Anything wrong with it? I
> also looked for a way to convert the double "time" but I can't seem to find
> anything about reversing the byte order of 64bit types. Am I not supposed to
> use the htonl/htons functions for byte ordering? They only support unsigned
> 16 and 32 bit types(?)
>
> cheers, -thijs
>
>
> void CJitNet :: makeMatrixHeader(int planecount, int type, int *dim, int
> dimcount)
> {
>     long i;
>     int typeSize;
>
>     switch(type)
>     {
>         case 3:        typeSize = sizeof(double);
>                     break;
>         case 2:        typeSize = sizeof(float);
>                     break;
>         case 1:        typeSize = sizeof(long);
>                     break;
>         case 0:
>         default:    typeSize = sizeof(char);
>                     break;
>     }
>     m_chunkHeader.id = htonl(JIT_MATRIX_PACKET_ID);
>     m_chunkHeader.size =
> htonl(sizeof(t_jit_net_packet_matrix));
>
>     m_matrixHeader.id = htonl(JIT_MATRIX_PACKET_ID);
>     m_matrixHeader.size =
> htonl(sizeof(t_jit_net_packet_matrix));
>     m_matrixHeader.planecount = htonl(planecount);
>     m_matrixHeader.type = htonl(type);
>     m_matrixHeader.dimcount = htonl(dimcount);
>
>     for(i=0; i < dimcount; i++) {
>         m_matrixHeader.dim[i] = htonl(dim[i]);
>     }
>
>     while(i < JIT_MATRIX_MAX_DIMCOUNT) {
>         m_matrixHeader.dim[i] = 0L;
>         i++;
>     }
>      //special case for first value
>     m_matrixHeader.dimstride[0] = htonl(typeSize * planecount);
>
>     for(i=1; i
>         m_matrixHeader.dimstride[i] =
> htonl(dim[i-1]*m_matrixHeader.dimstride[i-1]);
>     }
>
>     while(i < JIT_MATRIX_MAX_DIMCOUNT) {
>         m_matrixHeader.dimstride[i] = 0L;
>         i++;
>     }
>     m_matrixHeader.datasize
> htonl(m_matrixHeader.dimstride[dimcount-1]*m_matrixHeader.dim[dimcount-1]);
>     m_matrixHeader.time = 0.0; // 64bit byte order conversion??
> }
>
>
>
>
>
>
>
>
>


On 8-Nov-2006, at 17:31, Ben Nevile wrote:

> That header uses the below two functions:

Yeah, you _can_ do it that way, but only the following will warm the 

true C coder's heart (salt to taste for floats and doubles):

iBytes = ((iBytes >> 8) & 0x00ff00ff) | ((iBytes << 8) & 

return ((iBytes >> 16) & 0x0000ffff) | ((iBytes << 16) & 

On 8-Nov-2006, at 17:31, Ben Nevile wrote:
> That header uses the below two functions:

Yeah, you _can_ do it that way, but only the following will warm the  
true C coder's heart (salt to taste for floats and doubles):

   {
   iBytes = ((iBytes >>  8) & 0x00ff00ff) | ((iBytes <<  8) &  
0xff00ff00);
   return   ((iBytes >> 16) & 0x0000ffff) | ((iBytes << 16) &  
0xffff0000);
   }

> Yeah, you _can_ do it that way, but only the following will warm the

Oh Peter, I can always count on you to brighten my day! We use macros

short)(x))>>8)&0x00ff)+((((unsigned short)(x))<

long)(x))>>24L)&0x000000ff)+((((unsigned long)(x))>>8L)&0x0000ff00)+ 

                    ((((unsigned long)(x))<

> iBytes = ((iBytes >> 8) & 0x00ff00ff) | ((iBytes << 8) &

> return ((iBytes >> 16) & 0x0000ffff) | ((iBytes << 16) &

> Yeah, you _can_ do it that way, but only the following will warm the
> true C coder's heart

Oh Peter, I can always count on you to brighten my day!  We use macros
in jit.byteorder.h:

#define SWAP16(x) ((short)(((((unsigned
short)(x))>>8)&0x00ff)+((((unsigned short)(x))<
#define SWAP32(x) ((long)(((((unsigned
long)(x))>>24L)&0x000000ff)+((((unsigned long)(x))>>8L)&0x0000ff00)+ 
					((((unsigned long)(x))<
long)(x))<

(salt to taste for floats and doubles):
>
> UInt32
> ReverseBytes(
>    UInt32 iBytes)
>
>    {
>    iBytes = ((iBytes >>  8) & 0x00ff00ff) | ((iBytes <<  8) &
> 0xff00ff00);
>    return   ((iBytes >> 16) & 0x0000ffff) | ((iBytes << 16) &
> 0xffff0000);
>    }
>
> -- Because you didn't ask for it, P.
>
>
>

Thank you so much guys! I finally got it all working. I took me a while to

iron out some bugs that were hard to find. In the end everything was related

talking to jit.net.send from outside max