Bug: Sony Sharpen behaves differently with GPU - Fixed in VP14

NickHope wrote on 3/7/2015, 5:41 AM

In the old pre-GPU days, the Sony Sharpen FX always gave some sharpening even if the value was zero.

However in VP12 and VP13 I was pleased to see that a value of zero actually gives no sharpening, as it should be.

However, I've just noticed that if GPU acceleration is on in the Video Preferences, the FX still sharpens at value zero, and quite a lot. This is bad. It's another instance where we're outputting significantly different video depending on whether GPU acceleration is on or off.

Tested with an AMD HD6970 and Nvidia GX580, which are allegedly a couple of the most compatible cards.

Could anyone else please verify or otherwise this before I submit a bug report?

Comments

john_dennis wrote on 3/7/2015, 10:52 AM

In Vegas Pro 13, Build 428, I rendered a one frame PNG Image Sequence with my NVidia GTS 450 on and off.

GPU On

GPU Off

Project Here

* I observed a levels shift between the two output PNGs.

* When I put the two pictures back into Photoshop and display actual pixels, I do observe a "sharper" picture in the PNG from having GPU On. Look at the perforations in the seats.

Is your test for sharpness qualitative or do you have a quantitative measurement?

NickHope wrote on 3/7/2015, 11:43 AM

Thanks very much John.

I noticed on the histogram first, and then by eyeballing the preview. The historgram gets "wider" each end, as is normal for sharpening.

I'll submit a bug report.

TheHappyFriar wrote on 3/7/2015, 7:12 PM

SCS might not be able to do anything. Different GPU's do things differently and it could be your model is doing this itself and has nothing to do with Vegas.

NickHope wrote on 3/8/2015, 12:55 AM

@TheHappyFriar With respect, I'm not sure that's entirely true. My AMD and Nvidia GPUs are giving almost exactly the same result. At the very least I believe SCS should be able to make it so that zero sharpening actually gives zero sharpening regardless of the GPU setting.

For me, leaving GPU acceleration on now is a total non-starter for this reason because I am sharpening most of my footage and I need a consistent result, and sometimes a very slight amount of sharpening that isn't possible if GPU acceleration is on.

I did a more precise test by putting a generated media checkerboard on a 1920x1080p timeline. The dark squares are 0.3, 0.3, 0.3 and the pale squares are 0.7, 0.7, 0.7. I added sharpening with a value of zero. Here are the results. The difference between GPU-accelerated and non-GPU-accelerated is actually quite dramatic.

Sharpening with no GPU
Sharpening with Nvidia acceleration
Sharpening with AMD acceleration

Unlike the GPU-related Photoshop layers bug that I reported, I have verified that this bug does get rendered into the output files, rather than being just a preview bug.

TheHappyFriar wrote on 3/8/2015, 7:46 AM

Before I posted a reply I wanted to recreate the project on my computer but the checkerboard only lets me type in integers from 0-255 for the values. What are the values you're using?

wwjd wrote on 3/8/2015, 10:53 AM

I've noticed the "Zero Sharpen Effect" ever since VP11, but didn't realize it was created by GPU. Actually, most of the time, my GPU is off, and ZSE still occurs SOMETIMES and not always. For some reason, seems to occur LESS with my GH4 4K footage. I too noticed it visually, and even easier noticing the video scopes changed when popping Sharpen on and off repeatedly.
I'll be watching this thread as info develops here.

paul_w wrote on 3/8/2015, 11:07 AM

Since v11 and the introduction of GPU code, there have been a few problems with differences between CPU and GPU filters not behaving the same. Most errors got reported and fixed, it looks like this one didn't. I would just report the issue and let them fix it.

NormanPCN wrote on 3/8/2015, 3:48 PM

I am able to duplicate this report on my AMD 7950 setup using the checkerboard example shown.

One can report the problem and pray it gets fixed but I have my doubts given the HSL effect having been broken since VP12, GPU mode, AMD/Nvidia both.

NickHope wrote on 3/9/2015, 12:18 AM

TheHappyFriar, sounds like you're on a pre-VP12 version? The values don't really matter. I chose them arbitrarily. But they equate to 76.5,76.5,76.5 and 178.5,178.5,178.5.

I have reported the problem so let's see.

NormanPCN, thanks for alerting me to that HSL problem. I'll go test it and report it myself if I can reproduce it.

NickHope wrote on 4/7/2015, 2:30 AM

VP13.0 build 444 still has this bug.

NickHope wrote on 4/25/2015, 3:26 AM

I received a reply from SCS today that includes this:

"This is a known issue and is being considered. Thank you for reporting this issue and providing your system information."

MSmart wrote on 4/25/2015, 6:19 PM

For me, leaving GPU acceleration on now is a total non-starter for this reason because I am sharpening most of my footage and I need a consistent result,

Have you tried using robwood's method of using the Unsharp Mask?

Last post here:
http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=857169

NickHope wrote on 4/26/2015, 1:16 AM

Thanks MSmart. I haven't tried that but I will give it a go on my next project.

NickHope wrote on 9/20/2016, 3:00 AM

This bug is fixed in VEGAS Pro 14.0 (Build 161). Thanks!

[ Edit: But there's a new sharpening bug: https://www.vegascreativesoftware.info/us/forum/vp14-bug-minimum-vegas-sharpen-0-001-gives-way-too-much-sharpening--103981/ ]