This guide describes how to use HandBrake to convert a video with variable frame rate (VFR) to a constant frame rate (CFR). A VFR video exhibits fluctuating frames per second. VFR videos are typically generated from video conferencing or webinar tools that record a variation of content from still image slideshows to a talking presenter in motion. Whereas CFR videos are your traditionally produced content with a fixed frames per second.
Prerequisites:
- Download HandBrake
- Have a preexisting VFR video
Initial Settings
- Open the VFR video in HandBrake.
- Select Range as Seconds. We’ll be using this data later.
- Select Preset as HQ 1080p30 Surround. Feel free to choose otherwise, but this is a decent output.
Setting Dimensions
- Select Cropping as Custom and ensure all edges are set to 0.
- Ensure Storage Size dimension matches the video’s actual size.
Setting Filters
- Select Detelecine as Off.
- Select Interlace Detection as Off.
- Select Deinterlace as Off.
- Rest of the settings here should have been off to begin with.
Setting Video
- Ensure Video Encoder is set to H.264 (x264).
- Select Framerate (FPS) as 30 and toggle Constant Framerate.
- Select Quality as Average Bitrate (kbps) with 2-pass encoding enabled. The Average Bitrate will need to be calculated before set with a value. We recommend a bitrate between 10,000 and 15,000 Kbps.
Max Bitrate = 38,000 MBs / Video Seconds
Setting Audio
- On Track-0, select Codec as AAC Passthru.
- On Track-0, select a Bitrate between 128 and 320 Kbps. A good default value is 192 Kbps.
- Ensure there is only 1 track. If there are multiple tracks of audio, just select the corresponding track as None.
Setting Subtitles
- Select any tracks as None.
Setting Chapters
- Uncheck Create chapter markers.
- Save As a new file (e.g. asset-constant-framerate-30.mp4).
- Click Start to begin the conversion process.
Comparing the Original Asset to the New Asset
- Ensure video quality is consistent. No additional artifacts, motion oddities, etc.
- Ensure video is 1:1 with visual and audio tracks aligning.
- Compare audio and visual between the original asset and new asset by a side by side analysis.