Rendering Settings

Introduction

This document discusses the various settings on the Rendering page of Preferences.
IMPORTANT: It is essential to set the correct Frame Size and Frame Rate on the Rendering page for your projects.

Use Per-compound Settings

The Frame size, Pixel AR, and Frame rate rendering settings are saved with and loaded from the compound when Use per-compound settings is enabled:

NOTE: This feature allows you to work between multiple projects with different rendering settings easily. When the Use per-compound settings is turned on, the rendering settings are saved with the compound, eliminating the need to reconfigure them every time you switch between compounds.
However, in most use cases, rendering settings are guided by the constraints of your studio environment or specific production needs. This is why by default the Use per-compound settings is turned off. When it is turned off, modifications to rendering settings, such as changing the Frame rate, will apply universally to all compounds. This consistent setting enables you to easily use different compounds in various productions or studio setups.

Frame Size

The Frame size determines the default rendering resolution of the virtual cameras. The resolution is set in pixels.
Higher frame sizes, such as UHD (3840x2160), offer more pixels and therefore more detail, but they also demand more computing power.

It is strongly recommended to set the same Frame size as your production's final output resolution, which is the image your audience will eventually see.
NOTE: Setting a Frame size smaller than the final output will result in images that appear jagged and pixelated. Conversely, choosing a frame size larger than the final output will needlessly consume hardware resources, unless you intend to do this for specific purposes, such as reducing aliasing.

When selecting the Custom option, it is possible to enter a pixel size between 16 and 8192, inclusive. The maximum allowable Frame size is 8192, 8192 (width, height pixels):

NOTE: You can also choose from these preset options: DCI 4K (4096 x 2160), DCI 2K (2048 x 1080), UHD 8K (7680 x 4320), UHD+(5120 x 2880), UHD (3840 x 2160), QHD (2560 x 1440), FHD (1920 x 1080), HDV(1440x 1080), HD (1280 x 720), PAL (720 x 576), NTSC (720 x 480), WHUXGA (7680 x 4800), WHXGA (5120 x 3200), WQXGA (2560 x 1600), WUXGA (1920 x 1200), WSXGA (1680 x 1050), UXGA (1600x 1200), SXGA (1280 x 1024), WXGA (1280 x 800), XGA (1024 x 768), SVGA (800 x 600), VGA (640 x 480).

Pixel AR

Pixel AR stands for Pixel Aspect Ratio, which is different from the typical Aspect Ratio that is defined by the ratio of the Frame Size.
You should define the frame's aspect ratio by the Frame Size, and change Pixel AR only when the individual pixels are not square-sized in the digital image. In these cases, the Pixel AR describes the ratio between the width and height of a digital pixel.

The non-square pixels are common in old formats of PAL, NTSC, and HDV / HDCAM. For example in the case of HDV 1080, the frame aspect ratio is 16:9 while the frame size in pixels is 1440:1080 (4:3).

Pixel AR can also be used to squeeze the virtual world into an anamorphic lens' field of view. This is needed because the anamorphic lenses capture a wider field of view than the camera's pixel resolution.
This is similar to what happens in rendering when using Pixel AR in Aximmetry, the virtual camera's field of view is adjusted to the Pixel AR's ratio, but the rendering resolution stays the same as the Frame Size.

NOTE: You can define any ratio in the Custom option. You can also choose from these preset options: Square (1:1), PAL (16:15), PAL Wide (64:45), NTSC (8:9), NTSC Wide (32:27), HDV (4:3)

Frame Rate

The Frame rate sets how many frames per second (FPS) Aximmetry generates.
A higher frame rate typically results in smoother motion and a more realistic appearance in video, as it plays a crucial role in how the human eye perceives motion and detail in moving images. However, a higher frame rate also requires more computing power.

It is strongly recommended to set the same Frame rate as your production's final output frame rate—the frame rate that your audience will eventually see. If the Sync is turned on the final video output, then the Frame rate is automatically set to the appropriate value.
Additionally, it is recommended that your inputs, such as tracking and camera feeds, maintain a frame rate that is the same as Aximmetry's Frame rate to avoid a jittered and stuttered appearance.

It is important to note that Aximmetry will not only generate the video frames at this rate but also every other type of output and input will be generated and sampled at this frame rate. And almost every module in the Flow Editor will also be executed as many times per second as the frame rate.

When selecting the Custom option, it is possible to enter a Frame rate between 5 and 240, inclusive:

When selecting the Unlimited option, Aximmetry will not wait between frames and will try to generate as many frames as it can per second.
NOTE: You can also choose from these preset options: 23.976p, 24p, 25p, 29.97p, 30p, 50i (PAL), 50p, 59.94i (NTSC), 59.94p, 60i, 60p, 89.91p, 90p, 119.88p, 120p, 200p, 239.76p, 240p.

Video Outputs Frame Rate Sync

When using an SDI output, it is crucial to assign the Sync to the main SDI output in the Video Outputs window. When using HDMI or DisplayPort output, it is not strictly required to assign Sync to one of them, however, it is recommended.

When the Sync option is selected for an output, the frame rate of the Rendering will be overwritten by the Output device's frame rate:

This is also represented in the Rendering page as the Frame rate will turn grayed out:

Interlaced Mode

If you wish to use interlaced video output, the Interlaced mode of the Frame rate must be turned on. Read more about interlacing at the page.

Processor Load Display

Processor Load panel shows the various types of loads on the system. Using the Processor load display options in the Rendering settings, you can edit what is displayed and in what formats.

 

The GPU and CPU section indicates the percentage of the per-frame time allocation utilized by the respective hardware components. For example, if you observe a 50% load on the CPU, it implies that the CPU is using half of the available time between frames. This suggests that, at its current workload, the CPU has the potential to handle approximately twice the current frame rate. It is important to note that the reported CPU and GPU loads may not be entirely accurate, as your computer can dynamically scale down your hardware's performance depending on the current load or if the hardware is overheating.
When the Value option of the Processor load display is turned on, the duration taken by the GPU and CPU within a frame is shown in milliseconds (ms).
NOTE: The CPU and GPU values are not equivalent to the ones reported in Windows Task Manager.
NOTE: Adjustments to higher Frame Rate values leave less time for the GPU and CPU to complete the rendering of the frames. Consequently, they lead to an increase in GPU and CPU load even when no other changes are made to the compound.

FPS shows the current Frame rate. If your hardware is overloaded, then the FPS can drop under the Rendering setting's Frame rate value. This will cause frame drops in your live production which can cause your production to look laggy, stuttering, and jerky. Therefore, try to keep the FPS bar in green and never let it go into red. Before a live show, it is recommended to test your project for long durations during which the FPS shouldn't go into red.

VMem shows the usage of the video card memory. It mainly consists of the loaded textures, meshes, and shaders. Additionally, various modules within the camera compounds also consume a modest percentage of the VMem.
If the system runs out of VMem, it can cause Windows to become unstable.
When the Value option of the Processor load display is turned on, the exact VMem usage is displayed in megabytes (M).

NOTE: The Processor Load panel also shows the loads of remote machines in a Multi-Machine setup.

Further Consideration When Using the Flow Editor

Some of the Flow Editor modules interact with the Rendering settings or behave differently because of it. If you don't use the Flow Editor then you don't need to concern yourself about what is being written below.

Out Size Pins

In modules of the Flow Editor, the Frame Size of the Rendering settings sets the default value of Out Size pins.
For example, the Camera module has an Out Size pin. As long as this Out Size pin is set to 0,0, the Camera module will use the Frame Size resolution for its rendering resolution.
We can see the current rendered resolution if we peek at the video Out pin:

NOTE: In this case, 8192,8192 size was set in the Frame Size.

When using Unreal to render the virtual world instead of Aximmetry's Camera module or Render compound, we find an Out Size pin on the Unreal Project compound. This Out Size pin has the same behavior as in the Camera module:

NOTE: Camera compounds, like the Virtual, Tracked, AR, and LED Wall compounds, render in the resolution of the Frame size setting, because inside the camera compounds these modules are being used with 0,0 Out Size values.

Many other modules have an Out Size pin other than the Camera module, for example: the Checkerboard video source module, and these modules have the same behavior.
NOTE: In the case of Placer modules, the Out Size pin is only used when no video is connected to the Background video input pin.

Duration, Period, and Delay Pins

There are several modules with time-related pins. The values of these pins are measured in seconds.
However, if a Frames pin is turned on in the same module, then the duration is counted in frames, so it will not be affected by the elapsed time between frames.

Several modules feature time-related pins. The values of these pins are measured in seconds.
However, when a Frames pin is turned on within the same module, the duration is then counted in frames. This measurement method ensures that the duration is not influenced by the time elapsed between frames.

NOTE: If there is no Frames pin, you can divide the value of 1 by the System Params Module's Frame Rate pin to get how much a frame is measured in seconds.

Video Recorder Module

When the Video Recorder module is active and recording, and if its Frame Rate pin is not set to Realtime, it prompts the Flow Editor to adjust the Frame Rate, enabling the system to generate frames as rapidly as possible. The Video Recorder module then assembles each produced frame into a video file, adhering to the frame rate specified in the Video Recorder's Frame Rate pin:

This feature is beneficial for Offline rendering, allowing for an hour-long video to be rendered in less than an hour. Because Aximmetry will try to render as many frames as possible per second.
Additionally, using this feature enables rendering at quality settings that are significantly higher than what your computer could achieve in Realtime. Consequently, this would make the rendering last longer than the duration of the produced video.

System Params Module

You can read the current Rendering settings (Frame size, Pixel AR, Frame rate, and Interlaced) using the System Params module.

NOTE: When using the interlaced mode, for example in the case 50i, the System Params module's Frame Rate pin will return a 50 value. However, a Video Input module's Frame Rate pin will return the actual number of whole frames, which would be 25 when receiving a 50i video.

Set System Params Module

The Set System Params module can overwrite the Rendering settings (Frame size, Pixel AR, Frame rate, and Interlaced).