Comment 163 for bug 111257

$ xvinfo | grep max
    maximum XvImage size: 1920 x 1088
    maximum XvImage size: 1920 x 1088

This is what seems to be the relevant piece of xdpyinfo:

screen #0:
  dimensions: 1680x1050 pixels (331x207 millimeters)
  resolution: 129x129 dots per inch
  depths (7): 24, 1, 4, 8, 15, 16, 32
  root window id: 0x6c
  depth of root window: 24 planes
  number of colormaps: minimum 1, maximum 1
  default colormap: 0x20
  default number of colormap cells: 256
  preallocated pixels: black 0, white 16777215
  options: backing-store NO, save-unders NO
  largest cursor: 64x64
  current input event mask: 0x7a803f
    KeyPressMask KeyReleaseMask ButtonPressMask
    ButtonReleaseMask EnterWindowMask LeaveWindowMask
    ExposureMask StructureNotifyMask SubstructureNotifyMask
    SubstructureRedirectMask FocusChangeMask PropertyChangeMask
  number of visuals: 17
  default visual id: 0x23
  visual:
    visual id: 0x23
    class: TrueColor
    depth: 24 planes
    available colormap entries: 256 per subfield
    red, green, blue masks: 0xff0000, 0xff00, 0xff
    significant bits in color specification: 8 bits