入参添加：
-hwaccel videotoolbox
出参添加：
-vcodec h264_videotoolbox -b:v 2000K
完整代码
ffmpeg -y -hwaccel videotoolbox -i "0" -vcodec h264_videotoolbox -b:v 2000K -max_muxing_queue_size 9999 -preset superfast -f flv -r 30 -an "rtmp://127.0.0.1/live/abcdedf"
