Animated backgrounds/Carrara Hangs
I'm working on an animation which needs an animated background. I've rendered out the background using the spherical camera, composited it and compiled it into a movie. Works great. Then I set the movie as the scene background in Carrara and render -- only this time there are problems -- after rendering for a few minutes, Carrara will hang and has to be killed, restarted, scene file loaded, starting frame update, etc. After four attempts I only have 106 frames of animation.
Watching things, there is an increasing delay when starting to render a frame until the delay increases to infinity and Carrara simply stops responding. Given that this is new behavior to me, I wonder if what is happening is that to start rendering each frame Carrara must seek to the correct frame in the movie (instead of just advancing it frame-by-frame -- the FPS of the movie is the same as that of the render) and eventually just fails.
The number of frames rendered varies: first time was 31 frames, second got 23 frames, third 22 frames and fourth managed 30 frames.
I'm now trying again, starting from scratch instead of restarting with the next frame, have 33 frames and am crossing my fingers that it keeps going. It is showing the same pattern of increasing delays (cpu graph has spikes instead of being level, average frame render started at 5 seconds and is already 14 seconds).
But what I really want to know is if other people have rendered successfully with animated backgrounds.
edited to add: the delays are immediately due to excessive memory allocation. This is on OS X and it gets put down as kernel memory, but is allocated due to Carrara. I only have 32GB RAM and it got hard to tell for sure, but at one point it was at least 15GB into swap. I only got 44 frames out of the "render from scratch" attempt.
Comments
use an image series and save yourself a lot of grief
It does not appear possible to set an image series as a background. If I select an image it sets that image for the entire animation. I cannot set a directory, only a file.
I've worked out that there is a memory leak associated with using a movie as a background. With this particular scene I can render ~33 frames before it runs the system out of memory. Not a good way to render even a short movie (~2000 frames).
here we go
ah, thank you! It hadn't occurred to me that image sequence would be a separate file type. Saves me the trouble of making movies as an intermediate step *and* side steps the memory leak.
Also save your render as an image sequence to avoid a memory leak.
Not only that, but Carrara isn't exactly... stable... when rendering animations. I always render as image sequences. If anyone sees this thread, take note. Always do the movie using an external application.
another great thing about image series is you can oscillate the tweener to loop them back and forwards
you can use them as texture maps diffuse bump displace do waves etc or in gel lights too