Trouble with Capture Stage to Disk actor

Lauri

I wanted to return to this topic because of some issues – hopefully someone would have an idea to get over the issues.

First, even the capturing works, there’s a visual flaw when the capturing starts/stops: most of the time there appears a black frame (I suppose the first frame), and this black frame gets accumulated to the beginning of the video file leading it to “flicker”. The flicker last longer while the capture generation grows.

I suppose it could be avoided by a fade between the projected files. Hoswever, this is not possible because there’s no “extra” length in the video files that could be time-wise overlapping with each other.

So, I tried capturing another instance of the stage, but that does not seem to be possible. Isadora is capable of capturing only one camera or stage at a time, right?

The other problem I found is that the capture settings are always reset to default (Photo Jpeg), so changing the capture settings does not really work – if only changing the scene resets the capture settings. It would be useful to use something better than Photo-Jpeg in a cumulaitve video processing.

The third issue I mentioned earlier on this thread is the capture frame rate that does not seem to match with the settings. Let’s say I choose 25fps from the capture settings and 50fps in the Isadora preferences, it results to strange frame rates (like 48,67fps) and the fram rate changes by captured file. Is this a bug in Isadora?

Please, anybody, let me know if there is a solution to the above mentioned issues.

Thanks in advance,

Lauri

mark

@DusX

If there's stuff here I need to solve for v2.6, please write it up as a bug report so I can investigate. (The thread is a bit long for me to digest with everything else I've got to get done.)

Best Wishes,
Mark

mark

@lauri said:

First, even the capturing works, there’s a visual flaw when the capturing starts/stops: most of the time there appears a black frame (I suppose the first frame), and this black frame gets accumulated to the beginning of the video file leading it to “flicker”. The flicker last longer while the capture generation grows. I suppose it could be avoided by a fade between the projected files. Hoswever, this is not possible because there’s no “extra” length in the video files that could be time-wise overlapping with each other.

I am testing in v2.5.2 right now, and I see no black frame at the start of the capture. My test was performed on a 1920x1080 source stage window, with the Record Stage Settings set to capture at a custom size of 1280x720

So, I tried capturing another instance of the stage, but that does not seem to be possible. Isadora is capable of capturing only one camera or stage at a time, right?

That is correct. There is one instance of the object that captures the stage, so it can only work with one stage at a time.

The other problem I found is that the capture settings are always reset to default (Photo Jpeg), so changing the capture settings does not really work – if only changing the scene resets the capture settings. It would be useful to use something better than Photo-Jpeg in a cumulaitve video processing.

Well, it turns out this is the way it's been since forever. The Capture Stage To Disk option in the menu used to be a global thing, and so the settings were stored in the Preferences. No one ever complained before, but you're right that these settings should be stored with the Isadora file. For the v2.6 release, the codec, the frame rate, and the Record Stage Settings will all be stored with the Isadora document.

That said, my testing shows that this is setting is remembered as you don't close the file.

1) Choose Output > Compression Settings...
2) Choose Apple Pro Res 422
3) Capture, Capture, Capture... all movies are Apple Pro Res.

The third issue I mentioned earlier on this thread is the capture frame rate that does not seem to match with the settings. Let’s say I choose 25fps from the capture settings and 50fps in the Isadora preferences, it results to strange frame rates (like 48,67fps) and the fram rate changes by captured file. Is this a bug in Isadora

This is a bug, and I'll fix it. The frame rate, in the end, is determined by the target frame rate as set in the Preferences.

As far as the inaccuracies, it has to do with the rate at which the frames are delivered to the capture component from the main rendering thread. If it can't keep up in terms of delivering the frames, the frame rate may dip below the desired rate. That's much harder to solve, so I may not address it right now. In the end, this feature was intended to deliver excellent real time performance at the sake of some accuracy.

Best Wishes,
Mark

mark_m

@mark

While we're on this topic just to remind you that there's one dialogue box in Windows which still doesn't scale properly to the display: it's the output-> compressions setting dialogue box. This has been a long-standing bug and is still present in the latest version. As you can see the dialogue box doesn't quite scale to be able to include all the options, and one cannot size the box in order to do so.
Thanks
Mark

DusX

@mark_m said:

This has been a long-standing bug and is still present in the latest version.

I'm sorry, I take ownership of this oversight. I was aware of this and lost track of it. Thanks for the reminder. I'll get it I to the system right away so that mark can deal with it.

mark

@mark_m said:

that there's one dialogue box in Windows which still doesn't scale properly to the display:

Yes, well, I'm not quite sure what to do about that. I'm just telling QuickTime to show the dialog, and it does what it does. Remember: Apple stopped developing QuickTime for Windows years ago. It's not high-DPI aware, etc., etc. So, there may not be a solution for this until we drop QuickTime and I implement this capture stuff natively on Windows. But that's down the pike a little bit.

Best Wishes,
Mark

artoo

"and the Record Stage Settings will all be stored with the Isadora document."

thanks a lot @mark, this feature will be very appreciate here. Btw, did the "quality" of the recording will be save too? ´cause for my purpose i have to change this setting every time i open isadora.

mark_m

@mark

Oh yes, I see: I hadn't appreciated that it's a QT dialogue rather than an Isadora one. So no, I don't know what you can do about it!!!

Thanks

Mark

Lauri

@mark

"I am testing in v2.5.2 right now, and I see no black frame at the start of the capture. My test was performed on a 1920x1080 source stage window, with the Record Stage Settings set to capture at a custom size of 1280x720"

Yes Mark, you are right, my mistake. The black frame came from video mixer that had no input for the duration of a frame – and then that cumulated to flicker.

No one ever complained before, but you're right that these settings should be stored with the Isadora file. For the v2.6 release, the codec, the frame rate, and the Record Stage Settings will all be stored with the Isadora document.

That said, my testing shows that this is setting is remembered as you don't close the file.

1) Choose Output > Compression Settings... 2) Choose Apple Pro Res 422 3) Capture, Capture, Capture... all movies are Apple Pro Res.

Thanks Mark, storing codec, frame rate and Record Stage Settings with the Isadora document is a great improvement. For an installation, it's very important to be able to have these settings pre-selected.

Best wishes,

Lauri

Lauri

... oh, sorry, forgot to tell that I succeeded to make a scene like my original purpose was: "I’m trying to do a project where the realtime camera accumulates continuously to a video. The camera image is superimposed to previous takes from the same stationary camera – like “superimposed layers of the past with the present moment”."

The trick was to slow down the playback of the captured files and then "cross dissolve" these. However, the project seems unstable, crashing every 10minutes or half an hour.

Here's the crash report:

Isadora_2017-12-10-213942_bliju.crash.zip

Best,

Lauri

mark

@lauri

It's crashing in the process that accumulates images to write as part of the Capture Stage to Disk process. Any way you'd be willing to PM me your patch (or post it here if you don't mind) so I can run it and try recreate and solve the issue?

Best Wishes,
Mark

Lauri

@mark

Thanks for looking at my issue. Here’s the patch:

livecapturetest++.izz.zip

There are 3 scenes inside the Isadora document.

First and second are the ones that don’t have the black frame issue (first scene is cleaned up with a macro, but otherwise the first and second are identical). But the first and second scenes are crashing, usually after around 20-30minutes.

The third scene is simpler with only two captures, doesn’t crash, but has this “black frame” issue – and for some reason starts sometimes accumulate files (instead of replacing the two files). If it didn’t have the black frame issue, I would rather use this patch. I tried using video delay actor (just 1-2 frames), which took the black frame away, but it was very processing intensive slowing down Isadora.

Thank you in advance!

Lauri

mark

@lauri said:

Thanks for looking at my issue. Here’s the patch:

I just want to add that, given my schedule trying to wrap up v2.6, I cannot promise how quickly I can get to this. I'll do it as soon as I can squeeze it in, but it might be 2-3 days.

Best Wishes,
Mark

Lauri

@mark

No problem, thanks for letting me know!

Best,

Lauri