In terms of 27MHz MPEG-2 clocks 60fps 450000 ticks/frame 59.94fps 450450.45045045045045045045045045... ticks/frame 30fps 900000 ticks/frame 29.97fps 900900.9009009009009009009009009... ticks/frame 25fps 1080000 ticks/frame 24fps 1125000 ticks/frame 23.976fps 1126126.1261261261261261261261261... ticks/frame -------------------------------------------------------------------------------- -- calculation to avoid inaccuracies in 59.94fps counting against 27MHz clock -- -------------------------------------------------------------------------------- 27000000MHz / 59.94fps = 450450.45045045045045045045045045... 2700000000 / 5994 = 450450.45045045045045045045045045... 1350000000 / 2997 = 450450.45045045045045045045045045... 450000000 / 999 = 450450.45045045045045045045045045... 50000000 / 111 = 450450.45045045045045045045045045... 111 * 450450 = 49999950 50000000 - 49999950 = 50 50 / 111 = 0.45045045045045045045045045045045... -------------------------------------------------------------------------------- -- calculation to avoid inaccuracies in 29.97fps counting against 27MHz clock -- -------------------------------------------------------------------------------- 27000000MHz / 29.97fps = 900900.9009009009009009009009009... 2700000000 / 2997 = 900900.9009009009009009009009009... 900000000 / 999 = 900900.9009009009009009009009009... 100000000 / 111 = 900900.9009009009009009009009009... 111 * 900900 = 99999900 100000000 - 99999900 = 100 100 / 111 = 0.9009009009009009009009009... -------------------------------------------------------------------------------- -- calculation to avoid inaccuracies in 23.976fps counting against 27MHz clock -- -------------------------------------------------------------------------------- 27000000MHz / 23.976fps = 1126126.1261261261261261261261261... 27000000000 / 23976 = 1126126.1261261261261261261261261... 6750000000 / 5994 = 1126126.1261261261261261261261261... 3375000000 / 2997 = 1126126.1261261261261261261261261... 1125000000 / 999 = 1126126.1261261261261261261261261... 125000000 / 111 = 1126126.1261261261261261261261261... 111 * 1126126 = 124999986 125000000 - 124999986 = 14 14 / 111 = 0.12612612612612612612612612612613...