Ferrite-garnet films with one A1 and two A1 and A2 amplitude-frequency regions of anger state existence are investigated. Regularities describing the quantitative characteristics of dynamic domain structure in relation to ac magnetic field frequency variation are found. The A1-A2 transition is accompanied by the emergence of gigantic dynamic domains. For both the A1 (102- 104 Hz) and A2 (104-105 Hz) ranges, the dynamic fragmentation of domain structure with increase in the field's frequency is characteristic. For interpreting qualitatively the results obtained, a simple theoretical model is used.