Create a video file (e.g. mpeg) of the 3D Data

cr_itm · Post by **cr_itm** » Wed May 25, 2005 11:16 pm

Hello,

I can save some 3D information about my screen, where the objects are, the position of the camera and the movement of the objects, so I can load the file and re-play the scene.

Now my question is, how can I create a video file out of it? My program just plays the 3D scene "realtime" and should write every frame to a video file (at best compressed).

Do you have any idea how to do that?

Thanks a lot!

X_for_Extra · Post by **X_for_Extra** » Wed May 25, 2005 11:23 pm

I've been thinking about that too. An mpeg file writer would be niffty for making demos and stuff.
What I think is the easiest route is to write a series of screen shots, jpegs if possible and then use an external app to convert them into a video clip.

I think FFMpeg has this capabillity.

But a native mpeg exporter would totally rock.

Maybe Directshow has some provisions for this?

afecelis · Post by **afecelis** » Wed May 25, 2005 11:33 pm

use fraps and capture your realtime experience!

http://www.fraps.com

cr_itm · Post by **cr_itm** » Fri May 27, 2005 7:22 pm

X_for_Extra wrote:I've been thinking about that too. An mpeg file writer would be niffty for making demos and stuff.
What I think is the easiest route is to write a series of screen shots, jpegs if possible and then use an external app to convert them into a video clip.

I think FFMpeg has this capabillity.

But a native mpeg exporter would totally rock.

Maybe Directshow has some provisions for this?

Yes indeed, a mpeg writer would be great, but for me it is import, that I can just save the pictures, the engine is rendering. Do you have any ideas how to do that? I dont know how I can save one frame of my animation into a file...

hybrid · Post by **hybrid** » Fri May 27, 2005 10:31 pm

Using Linux there is always an image generated in every render round. This could be easily captured by some mpeg encoding library. I never used mpeg encoding, but I will have a look in the next days. But need to check version 0.10 before!

cr_itm · Post by **cr_itm** » Sun May 29, 2005 12:18 am

hybrid wrote:Using Linux there is always an image generated in every render round.

Using Linux? What do you mean... is it linux specific, that there is always an image generated in the render round?

My questions was, how in general can I save an image of the screen to a file? OR in other words, how do I capture a screen (render output of irrlicht)?

hybrid wrote: This could be easily captured by some mpeg encoding library. I never used mpeg encoding, but I will have a look in the next days. But need to check version 0.10 before!

Version 0.10 of what?

hybrid · Post by **hybrid** » Sun May 29, 2005 9:46 am

cr_itm wrote:Using Linux? What do you mean... is it linux specific, that there is always an image generated in the render round?

I only know the Linux side of Irrlicht. But if the image is available on Window as well you can do it there as well. I will give it a try in the next days.

cr_itm wrote:Version 0.10 of what?

Irrlicht

puh · Post by **puh** » Mon May 30, 2005 12:15 pm

I did this in my demo simply taking screenshots of every cycle in the loop. Than using virtualdub it's pretty simple to make an avi file.
But beware - 4 minuts of bmp images takes alot of memory, in my machine with 800x600 screenshots it takes me more than 6GB

Guest · Post by **Guest** » Sat Jun 04, 2005 2:21 pm

why don't you use the render to texture feature ?

cr_itm · Post by **cr_itm** » Sun May 21, 2006 10:42 pm

Anonymous wrote:why don't you use the render to texture feature ?

How would render to a texture help to generate a video?

vegeta · Post by **vegeta** » Fri May 26, 2006 5:46 am

the render to texture would help makes it flat instead of 3d but then you still need to export it as a video

Acki · Post by **Acki** » Fri May 26, 2006 1:24 pm

After the render to texture you also have direct memory access to the textures pixle data (look for ITexture->lock() and ITexture->unlock() )...
Maybe you then can save the data to disc...

bitplane · Post by **bitplane** » Fri May 26, 2006 3:47 pm

i dont think you can lock a render target (yet). you can however grab screen data using either directx or opengl. see here for opengl.
Emil Halim's Magic2d library can record to divx avi, I assume this is using directx and vfw or something

turboferret · Post by **turboferret** » Wed Jun 07, 2006 10:54 pm

bitplane wrote:i dont think you can lock a render target (yet). you can however grab screen data using either directx or opengl. see here for opengl.
Emil Halim's Magic2d library can record to divx avi, I assume this is using directx and vfw or something

I posted a fix to locking d3d8/d3d9 rendertarget textures some time ago. I guess it hasn't made it into any of the builds after I posted it. Here it is.