The avi files are compressed using the MSU lossless codec:

http://compression.ru/video/ls-codec/index_en.html

They contain enlargements by the following methods:

  bilinear
  bicubic
  spline36
  lanczos (3-tap)
  lanczos (4-tap)
  spline64
  nnedi
  nnedi2 (nsize=0)
  nnedi2 (nsize=1)
  nnedi2 (nsize=2)
  eedi2 (maxd=3)
  eedi2 (maxd=6)
  eedi2 (maxd=12)

   ** nnedi3 enlargments are stored as separate png images
   **   Settings were: (in v0.9 syntax) nsize=0,nns=3,qual=2