Encoding an UHD sequences with HEVC HM reference software takes days on CPU’s even with monster computers, I want to know if it’s possible and then how to increase the number of threads (even if it decreases the quality of the encoding) to speed up the process (I want it to rise up to x4 times at least).
is this possible by increasing number of tiles , because by default there is only one tile per pic, or should we change in the source code? and where exactly?!
seems that the answer to increase encoding speed was not the number of tiles but the WPP. the HM gives the possibility to increase the number of tile in condition that the min tile with is 4 CTU (4*64 pel) and min height is 1 CTU (64pel). so, u can’t just choose any number .
when you activate the WPP , you can have up to 17 line in same time , but you cannot use WPP and tiles in same time.
testing this with basketballdrive HD seq QP=37 :
T(sec) Rate(kbps) PSNR
1 tile : 171013.381 1761.7472 34.5743
4 tiles : 166401.603 1822.1880 34.5439 = saves about 3 hours
WPP : 166187.201 1785.4048 34.5483 = ~same
could saves more with UHD seq but it's not enough for me. 3h is nothing for JEM and WPP are removed from the new VTM (FVC).