# Parameters

I tested on ffmpeg 3.2.x Hypatia.

## Container: MP4

| Parameter | YouTube recommends setting |
|---------------------|-------------------------------------------------|
| -movflags faststart | moov atom at the front of the file (Fast Start) |

## Video codec: H.264

| Parameter | YouTube recommends setting |
|---------------------|----------------------------|
| -profile:v high | High Profile |
| -bf 2 | 2 consecutive B frames |
| -g 30 | Closed GOP. GOP of **half the frame rate**. |
| -coder 1 | CABAC |
| -crf 18 | Variable bitrate. |
| -pix_fmt yuv420p | Chroma subsampling: 4:2:0 |

## Audio codec: AAC-LC

| Parameter                   | YouTube recommends setting                              |
|-----------------------------|---------------------------------------------------------|
| -c:a aac -profile:a aac_low | AAC-LC                                                  |
| -b:a 384k                   | Recommended audio bitrates for uploads: Stereo 384 kbps |