Why does movie frame node take so many CPU resources?

[Eric_bjtu]

Hi all,

I want to use image sequence frames to achieve some good effects.

But after I use the Movie Frame node and add the image file to the node, the CPU resouces are occupied a lot.

What's worse, after added a little more Movie Frame Nodes, the CPU is 100% occupied...

The images what I used are very small, mostly are only 100kb per picture. The amount of one group of image sequence frames is about 25 pictures.

Is anyone here meet the same problem? How to solve it? T.T

Thanks a lot.

Eric

[Karol]

Hi Eric!

What is the resolution of the images and the codec?

Cheers
Karol

[Eric_bjtu]

Hi Eric!

What is the resolution of the images and the codec?

Cheers
Karol

Hi Karol,

The resolution of the images is 2048 * 2048.
Sorry I don't know how to find what my codec is...

I found something useful in the user manual:

There are some rules that should be considered when working with a lot of images and textures. Keep in mind that the graphics card has only a limited amount of memory which is not only used for textures but also for geometries. The textures are stored in an uncompressed format in the graphics memory. A texture with the dimension 1024 x 1024 pixels and 24 bits color depth requires about 3 MB memory on the graphics card even if it originally was a .jpeg file with a size of 200 KB.


Use textures as small as possible. Typically it does not make any sense to use textures with the dimensions of 2048 x 2048 if the render output only has a resolution of 1280 x 720. Use as few textures as possible. Many texture swaps in every frame have a bad impact on the performance. To avoid this join many small textures to one big texture and use the Mapping Node to access the required sections during rendering.


When working with gradient textures where the gradient is 1-dimensional (texture color changes only in X or Y direction) it is recommended to use textures that are only 1 pixel high or wide (e.g. 512 x 1 or 1 x 512 pixels). A texture in such dimension contains all necessary gradient information. The texture is automatically stretched if it is applied to a geometry and the memory saving is enormous compared to a 512 x 512 texture.


Use the Texture Loader Node to load textures and images. This Node loads faster and requires less memory than the Image Loader Node. The Image Loader always keeps an additional copy of the original image in memory and not only the texture which will be used by the graphics card.

So I try to use movie clip with alpha channel instead of the movie frame, and it does work~!

Thanks a lot~

Cheers,
Eric

[Eric_bjtu]

Hi Eric!

What is the resolution of the images and the codec?

Cheers
Karol

Hi,

I find the reason why the movie frame consumes so many CPU resources.

The default buffer of the movie frame is 10.

After I set Buffer settings to "Buffer all(decode entire clip into RAM), the problem is solved.