Although the command-response model for the process of F0 contour generation has been successfully applied to many languages, the inverse problem, viz., automatic derivation of the model parameters from an observed F0 contour, is more challenging, especially for tone languages which have tone commands of both polarities. Since the polarities of tone commands cannot be inferred directly from the F0 contour itself, the information on tone identity and timing need to be incorporated. The current study gives a general approach for the first-order estimation of tone command parameters for tone languages, taking Mandarin and Cantonese as two examples. After a rule-based recognition of the tone command patterns within each syllable, the timing and amplitude of tone commands will be deduced. The experiments show that the method gives good results of analysis for both the two dialects.