On 22-02-2019 03:50 AM, Moses DeJong wrote:
When creating Y4M with 30 FPS frame rate:

ffmpeg -y -i CarSpin.y4m -c:v libx264 -pix_fmt yuv420p -preset:v slow 
-profile:v main -tune:v animation -crf 23 -color_primaries bt709 -color_trc 
iec61966_2_1 -colorspace bt709 CarSpin.m4v

CarSpin.m4v
977422 bytes
977 KB

When the same video data is written as Y4M with a 1 FPS header.

(ffmpeg command line is the same)

CarSpin.m4v
4000022 bytes
4 MB

...

What might be going on here and how could I get ffmpeg or x264 to get the 
higher compression results seen with 30 or 60 FPS in the Y4m header but with 
the low frame rate settings in the header? The frame rate defined in the M4V 
output header controls playback rate and I am not able to say encode a 30 FPS 
video and then play it back at 1 FPS on the client side.

x264 modulates rate control, taking into account, frame duration, which is much larger for a 1 FPS video than 30 FPS.

See https://stackoverflow.com/a/49623331/5726027

Gyan
_______________________________________________
ffmpeg-user mailing list
[email protected]
https://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[email protected] with subject "unsubscribe".

Reply via email to