Doom9's Forum - View Single Post - Video sequence that gives worst compression

rosh · 27th October 2015, 18:19

Hi,

I did another experiment with a random 'coloured noise' video (generated via : ffmpeg) : http://stackoverflow.com/questions/1...ating-tv-noise

which gave me about 74% compression.

This is all lossy compression. Using the HEVC encoder (x265, default parameters).

For coloured noise video :
Avg QP:41.44,

For grayscale noise video :
Avg QP:35.62

This article says that standard H.264 can achieve good quality video at 100:1 compression for normal video sequences. I've tried many test sequences mainly of fast motion video, and they too were around 98%-99%.

I guess is also depends on the level of entropy - maybe /dev/urandom isn't purely random to give low compression.

27th October 2015, 18:19	#3 \| Link
rosh Registered User Join Date: May 2015 Posts: 11	Hi, I did another experiment with a random 'coloured noise' video (generated via : ffmpeg) : http://stackoverflow.com/questions/1...ating-tv-noise which gave me about 74% compression. This is all lossy compression. Using the HEVC encoder (x265, default parameters). For coloured noise video : Avg QP:41.44, For grayscale noise video : Avg QP:35.62 This article says that standard H.264 can achieve good quality video at 100:1 compression for normal video sequences. I've tried many test sequences mainly of fast motion video, and they too were around 98%-99%. I guess is also depends on the level of entropy - maybe /dev/urandom isn't purely random to give low compression.