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Old 07-03-2019, 09:56 PM   #8
Liverpool TV
Senior Member
Join Date: Nov 2013
Location: Liverpool, England.
Posts: 2,887

Originally Posted by BernH View Post
Correct Dave. I should have qualified my earlier statement about H265 looking better, by stating that it is likely to occur at lower bitrates due to the efficiency of H265 compared to H264.

I hang my head in shame. ;)
Hi Bern.

I do it all the time. You wouldn't believe how many times I've stopped an export because I've forgotten and bypassed the wrong or right codec. Especially where file size isn't an issue.

Funny enough, there are instances where H.264, depending on the encoder, will produce a better final delivery or intermediate due to a particular encoder's inability to encode 10 Bit and 4:2:2 with H.265 but not with H.264. Edius and QS is actually a good example of this.

The limited ceiling for both chroma and bit rate with E9/QS for H.265 will mean that H.264, even QS in Edius, will yield a better results in certain scenarios. More so for UHD/60 from a 10 Bit 4:2:2 master/timeline, where the upper limits of E9/QS's bit rate and chroma are simlply not enough but H.264 is.

At the moment I'm doing a large number of tests to see about maximising YouTube encodes. One of the tests is to see where the trigger is for VP9 encoding and the other is try and work out if YT uses any dithering when doing down/cross conversions and if so, where does that occur.

This all means doing many intermediates that have true and false bit depths and chroma sub sampling. Basically expanding/padding 8 Bit 4:2:0 into 10 Bit 4:2:2 and also using true 10 Bit 4:2:2 and see if any of this fools YT to use dithering for its 8 Bit 4:2:0 H.264 and VP9 outputs, if it does.

Here's a video that I've just uploaded. Although this is a proper product test video, I've done certain things with this to test to guague for certain results. This is all padded for bit depth and chroma and uploaded as H.264 10 Bit 4:2:2 at 200Mb/s.


"There's only one thing more powerful than knowledge. The free sharing of it"

If you don't know the difference between Azimuth and Asimov, then either your tapes sound bad and your Robot is very dangerous. Kill all humans...... Or your tape deck won't harm a human, and your Robot's tracking and stereo imagining is spot on.

Is your Robot three laws safe?

Last edited by Liverpool TV; 07-04-2019 at 04:36 PM.
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