ComfyUI Node: 🐇 RIFE VFI FPS Resample

🐇 RIFE VFI FPS Resample:

RIFE_FPS_Resample is a powerful node designed to convert video clips from one frame rate to another using the RIFE (Real-Time Intermediate Flow Estimation) models, specifically versions 4.7 and 4.9. This node is particularly beneficial for AI artists and video creators who need to adjust the frame rate of their clips for various purposes, such as creating smoother slow-motion effects or matching the frame rate of different video sources. The node can handle both integer and non-integer frame rate changes, synthesizing intermediate frames for non-integer conversions to ensure smooth transitions. Additionally, it offers optional stabilizers to reduce flicker and protect edges, enhancing the visual quality of the output. By leveraging advanced interpolation techniques, RIFE_FPS_Resample provides a seamless and efficient way to resample video frame rates while maintaining high-quality results.

🐇 RIFE VFI FPS Resample Input Parameters:

ckpt_name

This parameter allows you to choose between the RIFE 4.7 or 4.9 model files, which are used for testing candidate timings. The available options are rife47.pth and rife49.pth, with rife47.pth set as the default. Selecting the appropriate model can impact the quality and speed of the frame interpolation process.

frames

This parameter represents your input video clip, where each frame is provided as an individual image. It is crucial for the node to have at least two frames to perform interpolation effectively.

fps_in

This parameter specifies the current frame rate of your input clip, measured in frames per second (FPS). It accepts values ranging from 1e-6 to 1000.0, with a default of 24.0 FPS. Accurate input of the current frame rate is essential for correct resampling.

fps_out

This parameter defines the target frame rate you wish to achieve for your output clip, also measured in FPS. It accepts values from 1e-6 to 2000.0, with a default of 60.0 FPS. Setting this parameter correctly ensures that the output video meets your desired specifications.

scale_factor

This parameter controls the quality versus speed trade-off for the interpolation process. It offers options of 0.25, 0.5, 1.0, 2.0, and 4.0, with 1.0 recommended as the default. Lower values result in faster processing with softer results, while higher values provide sharper results at the cost of speed.

ensemble

This boolean parameter, set to True by default, enables blending of forward and backward predictions to reduce artifacts. While this option can slow down the process, it enhances the visual quality of the output by minimizing interpolation errors.

multiplier

This integer parameter determines how many new frames you plan to create at the loop seam, specifically from the last to the first frame. It has a default value of 4 and a minimum of 0, where setting it to 0 will skip the frame creation process. Adjusting this parameter can help achieve smoother loop transitions.

🐇 RIFE VFI FPS Resample Output Parameters:

frames

The output parameter frames provides the resampled video clip, where the frame rate has been adjusted according to the specified fps_out parameter. The output frames are processed to ensure smooth transitions and high visual quality, making them suitable for further editing or direct use in video projects.

🐇 RIFE VFI FPS Resample Usage Tips:

• To achieve the best balance between quality and processing time, use the default scale_factor of 1.0, which provides a good compromise between speed and sharpness.
• When working with clips that require high visual fidelity, consider enabling the ensemble option to reduce artifacts, even though it may slow down the processing.
• If you are creating a looped video, adjust the multiplier parameter to control the number of frames generated at the loop seam, ensuring a seamless transition from the last to the first frame.

🐇 RIFE VFI FPS Resample Common Errors and Solutions:

ValueError: fps_in and fps_out must be > 0

• Explanation: This error occurs when either the input or output frame rate is set to a non-positive value, which is invalid for frame rate conversion.
• Solution: Ensure that both fps_in and fps_out are set to positive values greater than zero.

ValueError: required_duration must be less than video length

• Explanation: This error indicates that the specified duration for resampling exceeds the length of the input video.
• Solution: Adjust the fps_out or the number of frames to ensure the required duration is within the bounds of the input video length.