Watermark Height (mark-h)
The watermark will be mark-h pixels wide.
If only one dimension watermark dimension is specified, the other dimension will be calculated according to the aspect ratio of the input image. If both mark-h and mark-h are omitted, then the input image’s dimensions are used.
mark=object_id.png&mark-h=100

mark=object_id.png&mark-w=150&mark-h=200
