LEVEL_ZERO 81 libavcodec/ac3dec.c LEVEL_ZERO, LEVEL_ZERO 61 libavcodec/ac3enc.c LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO LEVEL_ZERO 67 libavcodec/ac3enc.c LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO