set_clock_speed  1464 fftools/ffplay.c        set_clock_speed(&is->extclk, FFMAX(EXTERNAL_CLOCK_SPEED_MIN, is->extclk.speed - EXTERNAL_CLOCK_SPEED_STEP));
set_clock_speed  1467 fftools/ffplay.c        set_clock_speed(&is->extclk, FFMIN(EXTERNAL_CLOCK_SPEED_MAX, is->extclk.speed + EXTERNAL_CLOCK_SPEED_STEP));
set_clock_speed  1471 fftools/ffplay.c            set_clock_speed(&is->extclk, speed + EXTERNAL_CLOCK_SPEED_STEP * (1.0 - speed) / fabs(1.0 - speed));