ffmpeg convert from H.264 (High 4:4:4 Profile) to H.264 (Main Profile)

Your source video has full-sized chroma planes - as indicated by the latter two 4s in YUV444P - and main profile doesn't support that format, so you'll have to select a pixel format like YUV 4:2:0

ffmpeg -i 1/25359.mp4 -vf "scale=2*trunc(iw/2):-2,setsar=1" -profile:v main -pix_fmt yuv420p out.mp4

The former answer was right, but I think the following answer was exactly what the asker want.

ffmpeg -i 1/25359.mp4 -profile:v main -pix_fmt yuv420p out.mp4
  • -profile:v: means which mode you want to encode video, there are some options here
  • -pix_fmt: yuv420p was allright for old videos.