PlaybackMode and In Frame Question

[samsc]

By way of introduction I wrote the interface that longred is using and I am helping to figure out what is going on in this cue sequence. My guess is the above question from josh is key, my guess is that Cataylst only acts on state changes. It makes sense, it is the way I would do it, especially with dealing with a streaming protocol like DMX.

yes. test your state changes.
dmx is a data stream not a command stream.
this is inherent in dmx.

they have to be thought through differently.

I have done my best in the past to try and work through these issues - and create a usable protocol without too many issues for the simplest of lighting consoles.

you need to change your states, and check what you see catalyst do, by looking in my HUD - it will show you everything you need.

---
another inherent problem is the defintion of 1 or 0 to be the floor state. - and how this is displayed to the user.
dmx values range from 0 to 255 per channel.
so 0 value has real meaning in dmx.

[stucotts]

yes. test your state changes.
dmx is a data stream not a command stream.

this is inherent in dmx.

they have to be thought through differently.

I have done my best in the past to try and work through these issues - and create a usable protocol without too many issues for the simplest of lighting consoles.

you need to change your states, and check what you see catalyst do, by looking in my HUD - it will show you everything you need.

---
another inherent problem is the defintion of 1 or 0 to be the floor state. - and how this is displayed to the user.
dmx values range from 0 to 255 per channel.
so 0 value has real meaning in dmx.

I know and understand DMX and state machines very well.

We found the problem today, it is a Catalyst problem.

As I mentioned the other night we are changing 3 things on this layer at the same time - selecting a somewhat large movie, setting playmode to Display InFrame and setting InFrame to 150. As we have seen over several performances and through packet analysis through wireshark. The movie is selected, Playmode is "display Inframe" and Inframe via HUD/Wireshark and all artnet monitoring devices is shown to be at 150 yet Catalyst is displaying frame 0 (1st frame of the movie)

We changed the cueing today so that the first cue selects the movie and sets PlayMode to Display InFrame and then a few seconds later set InFrame to 150 and all worked fine.

So it appears to me that the movie takes some time to load and by the time it is loaded Catalyst has tossed the state change from frame 0 to frame 150.

>>I have done my best in the past to try and work through these issues

I totally understand. You have done very well, Catalyst is a good product.

This is a minor issue but nonetheless an issue, it means that we need to be aware of not being able to pass all layer changes at once, probably when loading larger movies or maybe it is when several layers are doing 'some' amount of processing.

I find it a breath of fresh air that the developer of such a product is available to its users to ask questions and work through issues.

Thank-you,
Stuart

[samsc]

As I mentioned the other night we are changing 3 things on this layer at the same time - selecting a somewhat large movie, setting playmode to Display InFrame and setting InFrame to 150. As we have seen over several performances and through packet analysis through wireshark. The movie is selected, Playmode is "display Inframe" and Inframe via HUD/Wireshark and all artnet monitoring devices is shown to be at 150 yet Catalyst is displaying frame 0 (1st frame of the movie)

We changed the cueing today so that the first cue selects the movie and sets PlayMode to Display InFrame and then a few seconds later set InFrame to 150 and all worked fine.

So it appears to me that the movie takes some time to load and by the time it is loaded Catalyst has tossed the state change from frame 0 to frame 150.

it takes some time to "load a movie", and some time to get a particular frame in a movie. depends on many thing.
On my laptop here with internal drive it takes 40ms to load dv movie, and 10ms to get each frame.

there might be state interactions if you change state too quickly.
it might depend on the dmx update rate of your console.
Im checking some more.

[stucotts]

>>and create a usable protocol without too many issues for the simplest of lighting consoles.

I am curious, are you thinking of supporting ACN in the future?

Stuart

[samsc]

>>and create a usable protocol without too many issues for the simplest of lighting consoles.

I am curious, are you thinking of supporting ACN in the future?

Stuart

i like simple things.

i heard it was complex.

[stucotts]

i like simple things.

i heard it was complex.

At its core there are parts that are complex but very nicely ACN is being developed in opensource. For me SDT would be a bear to code.

DMX is a great protocol to replace what it replaced, streaming analog for dimmers. But at the end of the day the get/set properties of DMP will be wonderful for state machines such as moving lights, media servers, etc.

Check out
http://www.openacn.org/

I have been an observer to the ACN task group (I am missing the Phoenix meetings as I write) and it is a great group of people.

Stuart

[Spam Butterfly]

You need to do really clean and organised programming for media server programming. Play modes and in frame/out frame can really trip you up if you're not careful. A common technique with media server programming if firstly to 'preload' up coming movies on other layers (that's why you have 12 layers, right!).

DMX is a bit pants for media servers - but it's all we have at the moment. Who knows when ACN will be out...

Hugh

[stucotts]

A common technique with media server programming if firstly to 'preload' up coming movies on other layers (that's why you have 12 layers, right!).

DMX is a bit pants for media servers - but it's all we have at the moment. Who knows when ACN will be out...

Hugh

True... preroll is preroll. And that is how most state machines function...

But in this case Catalyst breaks the paradigm of what DMX is. And we cannot forget that DMX is a streaming protocol. All other devices out there do not act as state machines and only change when the state of the stream changes. If that is how the device needs to react then error checking is programmed to conform. Catalyst could see the request for loading a moive and request for InFrame of 150 and in the same packet and wait to do the Inframe when it is vaild to do.

All other devices out there in the world on a streaming protocol change when the stream changes. So it is an error for the movie to be in the state of frame 0 when the stream is asking for frame 150. 1 second/ 15 seconds later.... Irregardless of preloading/ preroll, on a streaming protocol this is an error.

Stuart