Blend Layer Y Position
blend-y
Places the blend layer image’s anchor vertically, measured from the top edge of the picture.
A value may be given in pixels, or as a fraction from -1.0 to 1.0 of the picture. Pixel values are multiplied by dpr on a still output that honors it; dpr does not apply to video output. The point of the image being placed is set by blend-anchor, which defaults to the top-left corner.
Setting blend-y causes blend-pad to be ignored on the vertical axis.
Aliases: blendy, by.
Use blend-y[N] to target a specific blend layer, where N is 0–3. Layer 0 is either the bare blend-y or blend-y[0]; if both are supplied, the bare name wins.
On a still that honors dpr, pixel values are rounded to whole pixels before dpr is applied. Fractional values are exact.