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Audio options:(오디오 옵션)

-ab                 set bitrate (in bits/s)(초당 비트레이트를 설정 ex)128, 192, 320 etc)
-aframes number     set the number of audio frames to record(녹음될 오디오 프레임들의 갯수를 설정함)
-aq quality         set audio quality (codec-specific)(오디오의 질을 설정함)
-ar rate            set audio sampling rate (in Hz)(오디오 샘플림을 설정함 32000,44000)
-ac channels        set number of audio channels(오디오 채널을 설정함 1-mono 2-stereo)
-an                 disable audio (오디오를 사용하지 않음)
-acodec codec       force audio codec ('copy' to copy stream)(음성 코덱을 설정함 'copy'는 복사)
-vol volume         change audio volume (256=normal)(볼륨을 설정함)
-newaudio           add a new audio stream to the current output stream(출력할 오디오 스트림을 현재 오디오 스트림에 추가함)
-alang code         set the ISO 639 language code (3 letters) of the current audio stream

Advanced options: (
-map file:stream[:syncfile:syncstream]  set input stream mapping
-map_meta_data outfile:infile  set meta data information of outfile from infile
-benchmark          add timings for benchmarking
-dump               dump each input packet
-hex                when dumping packets, also dump the payload
-re                 read input at native frame rate
-loop_input         loop (current only works with images)
-loop_output        number of times to loop output in formats that support looping (0 loops forever)
-threads count      thread count (쓰레드의 수를 지정)
-vsync              video sync method(비디오 싱크 도구 ex) -vsync 1)
-async              audio sync method(오디오 싱크 도구 ex) -async 1)
-adrift_threshold   audio drift threshold
-vglobal            video global header storage type
-copyts             copy timestamps
-shortest           finish encoding within shortest input
-dts_delta_threshold   timestamp discontinuity delta threshold
-programid          desired program number
-muxdelay seconds   set the maximum demux-decode delay
-muxpreload seconds  set the initial demux-decode delay
-sbsf bitstream filter