Configure FFmpeg xfade Transition Duration and Easing

This article explains how to configure the transition duration, start offset, and easing curves using the xfade filter in FFmpeg. You will learn the exact syntax required to apply smooth transitions between video clips, calculate timing offsets, and choose from various built-in transition curves to achieve professional visual effects.

The xfade (crossfade) filter in FFmpeg is the standard tool for applying transitions between two video inputs. Unlike the older fade filter, xfade supports dozens of transition shapes and easing curves. To apply the filter successfully, you must define the transition type, the start time (offset), and the duration of the effect.

Setting Duration and Offset

The two main parameters for controlling the timing of an xfade transition are duration and offset. Both values are expressed in seconds.

• duration: The length of time the transition effect lasts.
• offset: The exact timestamp in the timeline of the first video when the transition begins.

To calculate the correct offset, use this formula: Offset = (Duration of Video 1) - (Transition Duration)

If Video 1 is 10 seconds long and you want a 2-second transition, the offset must be set to 8 seconds.

Here is the basic command structure:

ffmpeg -i video1.mp4 -i video2.mp4 -filter_complex "[0:v][1:v]xfade=transition=fade:duration=2:offset=8[outv]" -map "[outv]" output.mp4

Choosing Transition Shapes and Easing Curves

FFmpeg does not use separate easing curve parameters (like Bezier curves); instead, it integrates easing styles and motion paths directly into its predefined transition options.

Below are some of the most common transition curves available in the xfade filter:

• fade: A standard linear crossfade where the first video fades out while the second fades in.
• wipeleft / wiperight / wipeup / wipedown: Linear gradient wipes moving in the specified direction.
• slideleft / slideright / slideup / slidedown: One video slides over the other, mimicking a linear motion curve.
• circlecrop / rectcrop: Easing transitions that expand or shrink in circular or rectangular shapes.
• dissolve: A pixelated noise-based transition curve.

To change the easing curve or transition style, simply change the value of the transition parameter:

ffmpeg -i video1.mp4 -i video2.mp4 -filter_complex "[0:v][1:v]xfade=transition=slideleft:duration=1.5:offset=8[outv]" -map "[outv]" output.mp4

Handling Audio Transitions

The xfade filter only processes video streams. To prevent abrupt audio cuts during the transition, you should pair the video xfade with the acrossfade audio filter. Match the audio transition’s duration and overlap to your video’s timing:

ffmpeg -i video1.mp4 -i video2.mp4 -filter_complex \
"[0:v][1:v]xfade=transition=fade:duration=2:offset=8[outv]; \
 [0:a][1:a]acrossfade=d=2:c1=tri:c2=tri[outa]" \
-map "[outv]" -map "[outa]" output.mp4

In this audio filter, d=2 sets the duration to 2 seconds, while c1 and c2 define the transition curves (e.g., tri for triangular, log for logarithmic, or lin for linear) to ensure the audio ease-in and ease-out match the video transition seamlessly.