VP17: Rendering HLG 4k UHD file w/ Hardware Acc & SLI corrupts video

Teagan wrote on 8/18/2019, 5:25 PM

This is related to my previous bug report about the preview not working with this file type but rendering was not a focus of the problem. After rendering the file and ignoring the preview problem, when the hardware acceleration is enabled, I get horrible flashing (the same sudden shift when I set the project to 32 bit floating point (full range) from 8 bit pixel format) and long grey bars at the bottom left. If I turn off hardware acceleration the video renders without a problem, on both machines.

I am trying to render an HLG source file (exact info below) to HLG in the same color space and when I do this with a computer with SLI GTX 1080 graphics cards (2x), the output keeps flashing between 8 bit pixel format and 32 bit floating point (full range), with random parts of the video being either the former or the latter, even different parts in the same frame. On another computer with the same exact file and same settings in VP17, with hardware acceleration, it renders fine. The only major difference is SLI between the two PCs. I have tried the studio drivers but the same problem happens.

Render settings:

MAGIX HEVC/AAC MP4 > HLG 4K UHD 2160P 59.94 fps with color space set to Rec. 2020 HLG (1000 nits)

the problem still occurs when color space is set to Rec. 2020 ST2084 (1000 nits).

Disabling hardware acceleration allows both of those to render without any problem.

My PC build is:

Windows 10 x64 update 1903

i7-8700k @ 4.3Ghz

Nvidia GTX 1080 founders edition SLI (2x) Driver Version 431.60 (also tried studio 430.86)

32GB RAM @ 3600Mhz

Samsung 970 Evo M.2 NVME 512GB

Laptop that doesn't have the problem:

Windows 10 x64 update 1903

i7-9750h

RTX 2070 Driver version 431.60

32GB RAM

Samsung 970 Evo M.2 NVME 512GB

Camera: Panasonic AG-CX350

Setting: HDR HLG 10 bit BT.2020 with 4k HEVC 200Mb/s

General
Complete name           : C:\Users\[removed]
Format                      : MPEG-4
Format profile            : QuickTime
Codec ID                   : qt   2011.07 (qt  /pana)
File size                   : 133 MiB
Duration                   : 6 s 6 ms
Overall bit rate          : 186 Mb/s
Encoded date            : UTC 2019-06-06 00:14:37
Tagged date              : UTC 2019-06-06 00:14:37

ID                          : 1
Format                   : HEVC
Format/Info            : High Efficiency Video Coding
Format profile         : Main 10@L5.2@High
Codec ID                : hvc1
Codec ID/Info          : High Efficiency Video Coding
Duration                  : 6 s 6 ms
Bit rate                    : 184 Mb/s
Width                       : 3 840 pixels
Height                      : 2 160 pixels
Display aspect ratio    : 16:9
Frame rate mode         : Constant
Frame rate                  : 59.940 (60000/1001) FPS
Color space                 : YUV
Chroma subsampling   : 4:2:0
Bit depth                   : 10 bits
Bits/(Pixel*Frame)       : 0.369
Stream size                 : 131 MiB (99%)
Language                    : English
Encoded date              : UTC 2019-06-06 00:14:37
Tagged date                : UTC 2019-06-06 00:14:37
Color range                 : Limited
Color primaries             : BT.2020
Transfer characteristics : HLG
Matrix coefficients         : BT.2020 non-constant
Codec configuration box : hvcC

Audio
ID                          : 2
Format                   : PCM
Format settings      : Big / Signed
Codec ID                : lpcm
Duration                 : 6 s 6 ms
Bit rate mode          : Constant
Bit rate                   : 2 304 kb/s
Channel(s)              : 2 channels
Channel layout         : L R
Sampling rate         : 48.0 kHz
Bit depth                  : 24 bits
Stream size            : 1.65 MiB (1%)
Language                : English
Encoded date          : UTC 2019-06-06 00:14:37
Tagged date            : UTC 2019-06-06 00:14:37

Other
ID                          : 3
Type                        : Time code
Format                      : QuickTime TC
Duration                    : 6 s 6 ms
Time code of first frame    : 12:06:03;05
Time code, striped          : Yes
Title                       : A016
Language                    : English
Encoded date                : UTC 2019-06-06 00:14:37
Tagged date                 : UTC 2019-06-06 00:14:37
Bit rate mode               : CBR

Comments

fr0sty wrote on 8/18/2019, 11:39 PM

You've done a great job isolating the bug and reporting it, but to make sure the devs see it, and so they have a support ticket to follow up on (and a direct line of communication with you should they need it), please fill out this support form. I'd include a link to this thread so they can easily get more info that you have posted here.

https://support2.magix.com/customer/en/vegas/form

fr0sty wrote on 8/18/2019, 11:41 PM

One more bit of info I'd include here are the driver versions you are using for those GPUs.

Wolfgang S. wrote on 8/19/2019, 2:58 AM

The development team is aware that more then one GPU can cause problems in Vegas. Results in different effects - sometimes no GPU support, sometimes no rendering. I know that because I have both a Quadro and an AMD in my machine, for some specific reasons

Interesting to read that this is also true for SLI. Thank you for that interesting finding.

Wolfgang S. wrote on 8/19/2019, 3:00 AM

By the way, I would not run the compositing gamma as linear but in the video setting. Output is different and typically we use video due to our perception of our eyes.