Update README.MD

ffmpeg/README.MD

@@ -13,6 +13,11 @@ ffprobe -v error -show_entries format=size -of default=noprint_wrappers=1:nokey=
 ffprobe -v error -show_entries format=bit_rate -of default=noprint_wrappers=1:nokey=1 <File>
 ```
 
+# 获取媒体文件编码
+```
+ffprobe -v error -select_streams v:0 -show_entries stream=codec_name -of default=noprint_wrappers=1:nokey=1 <File> |sort |uniq
+```
+
 # 视频文件直接切片
 ```
 ffmpeg -i <File> -threads 2 -thread_type slice -vcodec copy -acodec aac -bsf:v h264_mp4toannexb -map 0 -f segment -segment_list output.m3u8 -segment_time 10 output_%03d.ts