Master FFmpeg

#### I just want to see my beautiful face
```
ffplay -window_title "yingshaoxo" -vf hflip /dev/video0
```
___

#### Maybe record my screen with my voice
```
ffmpeg -y -f alsa -i hw:0 -f x11grab -framerate 30 -video_size 1920x1080 -i :0.0+0,0 -c:v libx264 -pix_fmt yuv420p -qp 0 -preset ultrafast ~/Videos/$(date +%F_%A_at_%H:%M:%S).mp4
```
___

#### You got it, I couldn't record without my beautiful face
```
ffmpeg -hide_banner -loglevel info -thread_queue_size 512 -y -f alsa -i hw:0 -thread_queue_size 512 -f x11grab -video_size 1920x1080 -i ":0.0" -thread_queue_size 512 -f v4l2 -video_size 320x240 -i "/dev/video0" -c:v libx264 -crf 30 -preset ultrafast -filter_complex 'overlay=main_w-overlay_w-10:main_h-overlay_h-10' -threads 0 ~/Videos/$(date +%F_%A_at_%H:%M:%S).mp4
```
___

#### Maybe do something to my face (camera)
```
ffmpeg -hide_banner -loglevel info -thread_queue_size 512 -y -f alsa -i hw:0 -itsoffset -1.266 -thread_queue_size 512 -f x11grab -video_size 1920x1080 -i ":0.0" -thread_queue_size 512 -f v4l2 -video_size 320x240 -i "/dev/video0" -c:v libx264 -crf 30 -preset ultrafast -filter_complex '[2:v]hflip[2:v];[1:v][2:v] overlay=W-w-10:H-h-10' -threads 0 ~/Videos/$(date +%F_%A_at_%H:%M:%S).mp4
```
___

#### That was cool! Let's do more!
```
ffmpeg -hide_banner -loglevel info -thread_queue_size 512 -y -f alsa -i hw:0 -itsoffset -1.266 -thread_queue_size 512 -f x11grab -video_size 1920x1080 -i ":0.0" -thread_queue_size 512 -f v4l2 -video_size 320x240 -i "/dev/video0" -c:v libx264 -crf 30 -preset ultrafast -filter_complex '[2:v]hflip[2:v]; [2:v]eq=brightness=0.04:saturation=0.7[2:v]; [1:v][2:v] overlay=W-w-10:H-h-10' -threads 0 ~/Videos/$(date +%F_%A_at_%H:%M:%S).mp4
```