Text Shadow Blur

Sets the Gaussian blur radius for the text drop shadow or glow effect on video overlays.

txt-shad-blur accepts an integer in pixels. Larger values produce a softer, more diffuse shadow or glow. A value of 0 produces a hard, unblurred shadow. Use txt-shad-blur[N] for a specific text layer.

This is a video-specific parameter with no direct equivalent in the image Rendering API. It extends the shadow system to allow soft glows, which improves text readability against varied video backgrounds.

https://assets.imgix.net/video.mp4?fm=mp4&txt=Hello&txt-color=FFFFFF&txt-shad-blur=8

For the full list of text overlay parameters, see the Text Overlays overview.