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Old 7th June 2010, 22:49   #405  |  Link
LoRd_MuldeR
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Quote:
Originally Posted by Kuningas View Post
CRF mode is much more smarter then 2-pass mode.
Nope, it isn't. Please stop spreading wrong information

Quote:
Originally Posted by Kuningas View Post
CRF raises the quantizers in "fast" scenes where the loss won't be visible anyway and lower the quantizers in "slow" scenes.
Correct, but applies to 2-Pass mode as well.

(Also you should say "blocks" instead of "scenes", now with MB-Tree rate-control being used)

Quote:
Originally Posted by Kuningas View Post
While encoding in two pass average bitrate mode "high motion" scenes will get a significant higher bitrate than "static" scenes.
Correct, but applies to CRF mode as well.

Quote:
Originally Posted by Kuningas View Post
That's why pq cann't be equivalent.
I guess you mean "CQP" (aka "constant quantizer"). And of course CQP cannot be equivalent to CRF/2-Pass. But CQP was never mentioned!


Example:

The upper one was encoded with 1-Pass CRF, the lower one was encoded as a "normal" 2-Pass:

(Note that both files have the same total size, i.e. the same average bitrate!)



You notice something regarding the bitrate distribution?

Upper: cabac=1 / ref=16 / deblock=1:-1:-1 / analyse=0x3:0x133 / me=umh / subme=10 / psy=1 / psy_rd=1.00:0.15 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-3 / threads=6 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / weightp=2 / keyint=750 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=crf / mbtree=1 / crf=24.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.40 / aq=2:1.00

Lower: cabac=1 / ref=16 / deblock=1:-1:-1 / analyse=0x3:0x133 / me=umh / subme=10 / psy=1 / psy_rd=1.00:0.15 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-3 / threads=6 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / weightp=2 / keyint=750 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=2pass / mbtree=1 / bitrate=284 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=2:1.00
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Last edited by LoRd_MuldeR; 7th June 2010 at 23:31.
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