The poster height, pixels
property PageWidthPix: Extended;
Posters are printed if PrintMode = srvpPoster.
Assigning to this property resets PageFormat to srvfmCustom.
Assigning any value (except for srvfmCustom) to PageFormat changes a value of this property.
Assigning to FrameCountX changes value of this property.
•the picture in the topic about TSRVPrint