version: 0.6.0
os macos 14.2.1

Panic occurs when calling the interface for adding watermarks.

is at the location shown in the screenshot.

Maybe we need to check whether the array is empty? It may also be that my file is not standard. Is the file just a blank pdf file? If necessary, I can send it to you for review.

// WatermarkContext applies wm for selected pages to ctx.
func WatermarkContext(ctx *model.Context, selectedPages types.IntSet, wm *model.Watermark) error {
return pdfcpu.AddWatermarks(ctx, selectedPages, wm)
}