Fractal Architect 4 Help Index

Video Rendering Topics

Applies to:FA 3DFA 3D-AV

See also: Keyframe Window Video Animations
See also: Audio/Video Utilities

Motion Blur

Motion blur is only used for video animation. It is done by sub-frame interpolation where animation interpolation is done multiple times for each frame.

The motion blur parameter (the number of sub-frames) is called Fan Blades. Its value is the number of sub-frame interpolations per video frame.

Fan Blades
Fan Blades

When the Fan Blades setting is equal to 1, this means that no motion blur is produced. The maximum number of Fan blades is equal to the number of render batches used by the render. Larger images and higher render quality produce more render batches.

Fractal Architect 4 makes Motion Blur and On/Off setting and shows the Fan Blade setting the app chose (which depends on your video frame size and render quality).

For very large videos like 1080p HD, experience has shown that a very high Fan Blades setting was causing significant rendering performance penalty. So in Fractal Architect 4, there is cap to the maximum Fan Blades setting (defaults to 200). The Adjust Blades Cap opens the Preferences window so you can change the default cap value.

Keep in mind that for years, most movies produced by Hollywood are limited to 60 sub-frames motion blur per video frame. That is the same as a 60 Fan Blade setting.

Larger image frames require more rendering, so the maximum amount of motion blur is greater.

For example, a render image size of 640 X 480 pixels (480p SD) at render quality 200 has maximum Fan blades of 19.
When the frame size is raised to 720p HD (1280X720), the maximum Fan blades of 57.

With Motion Blur
With Motion Blur
No Motion Blur
No Motion Blur

Breaking Up a Render Into Chunks

Rendering videos can take a long time.

Consider that a 1 minute video (at 30 frames/sec) has 1,800 individual video frames, each which is a different rendered fractal image. If it takes 10 secs to render each video frame using the CPU, the time to render a full minute of video will be 5 hours.

So clearly GPU acceleration makes sense here, if your Mac has that capability. A Macbook Pro with a separate discrete GPU might be able to render the video frames 4X times faster when you select to render with the GPU. That still takes 1 hour and 15 minutes to render a minute long video at 30 frames per second.

You can render a video in chunks so that your Mac is not tied up with rendering all of the time. The recommended way to render a long video is to first render out each video frame as its own image file. Then as a second step you convert the image file sequence to a video.

As an alternative approach, you can render separate video segments (each segment is its own video clip) and then later splice the videos together.

When you are at a place in the App where you can create a fractal animation, you can either:

Pros Cons
Make Image Sequence Can inspect each frame. Requires later conversion to video step
Memory efficient. Image sequence disk storage requirement
Can recover from app crash.
Make Video Simpler Memory inefficient - all frames in memory
One Step Not usable for long videos - 60 video frames at most
All rendering work lost if run out of memory

Render Frame Range Narrowing

Render Just a Subset of the Video Frames

When you first open the Render video dialog, the entire render range is selected to be rendered. You might want to break up the render into 30 frame chunks.

Note the Available frame count is 240 (which is the total un-narrowed frame count).

Render all frames
Render all frames

This frame range will render just the first 30 frames.
Here we set the frame Count value to 30 and the Start value is 0 - where 0 represents the first frame.

Render first 30 frames
Render first 30 frames

This frame range will render just the last 30 frames.
Here we set the frame Count value to 30 and the Start value is 210.
Note: Available value of 240 minus 30 equals 210.

Render last 30 frames
Render last 30 frames

Making Image File Sequences

Steps to Render to an Image file sequence:

  1. Click the Make Frames button.
  2. Pick video frame size, render quality.
  3. Pick a frame range to render. See Render Frame Range Narrowing.
  4. Click the Render! button.

Converting Image Sequence to Video

Use: File > Convert Image Sequence to Movie

  1. Pick the folder where the Image file sequence is.
  2. Pick a frame rate (defaults to 30 frames/sec) and a Video Bitrate for the video.
  3. Click the Make Movie button.

Making Small Videos

Steps to Render to a video:

  1. Click the Make Video button.
  2. Pick video frame size, render quality.
  3. Pick a frame range to render. See [Render Narrowing][Render Narrowing].
  4. Pick the Video nitrate and video framerate.
  5. Click the Render! button.

Splicing Video Segments

Use: File > Splice Videos Together

This will combine two video segments together into a new longer video.

Video Bitrate

Video Bitrate is the number of bits per second that the video uses.
The video size is directly proportional to this video bit rate.

Higher bit rates represent lower compression than higher bit rates.

Because of the video memory storage requirements, different mediums have different typical video bitrates. For Web sites, like YouTube or Vimeo, you should consult their documentation to see the appropriate video bitrates for the video frame sizes. Web usage is optimized for reasonable download times.

Setting the Video Bitrate

You choose the target device type first, then adjust the slider in the app to set the effective video bit rate.

Note: the only difference between the 3 device types is the amount of video compression applied. The output file formats are identical. To burn a DVD or Blue Ray disk, you can use iDVD (part of the iLife suite from Apple).