4K NVidia Encoder Large PNG Artifacts and/or Locked Renders

ccscotty wrote on 10/5/2020, 11:56 PM

I've noticed this issue in VP15 and it still exists in VP18 (build 334) after one test render now that I have that version. The render will have visual artifacts when showing the PNG images, or the render will get stuck in the process so that I have to force the application to close. I haven't tried recently, but I'm pretty sure it happened with large JPEGs as well.

This doesn't happen with the MainConcept based encoder. I'm glad because it allows me to actually do 4K with this style of video, but it takes significantly longer to render with this one compared to the Nvidia based encoder.

This doesn't happen at 1080p with the NV renderer from what I recall of past projects.

I tried rendering the portion of the video that failed. I had two images that should display for ~3 seconds on a pair of tracks, resized with the picture-in-picture FX plugin so that they fit on the screen side-by-side at 4K. They are 6000x4000 PNG images (~35MB each). I noticed in the preview window as it was processing frames, one of the images was completely not showing. After the render finished it was garbled from the point it tried to switch from a video clip to displaying the PNGs and then stayed garbled while trying to show the PNGs.

Often I include sample images in videos. Resizing them with the crop tool to fit in the screen, fit in a portion of the screen, or fit and be sized to a portion of the screen (crop tool plus picture-in-picture FX so I can show a portion of the image). It's easier to simply use the full sized images so I can show viewers what it looks like fit to the screen or what it looks like at 100% (photography tech videos...)

Computer:

Windows 10 Pro (19041.508)
Intel i7-6700
32GB RAM
MSI GTX 1060 6GB graphic card
Latest Nvidia Studio drivers (456.38)
I edit on a pair of 500GB in RAID 0, this issue existed on a single SSD drive as well.

Custom encoder settings used:
Magix AVC/ACC MP4
Audio: 384 Kbps, 48,000 Hz, 16 Bit, Stereo, AAC
Video: 29.970 fps, 3840x2160 Progressive, YUV, 44 Mbps
Pixel Aspect Ratio: 1.000

UHD 3840x2160
Profile: High (single pass)
Frame rate: 29.970
Encoder mode: NV Encoder
Field order: progressive scan
Variable bit rate: maximum of 70,000,000 and average of 44,000,000
Preset: high quality
RC mode VBR
Project: rendering quality Best, Color space Rec.709, color range Limited (default)

Comments

JN- wrote on 10/6/2020, 3:09 AM

@ccscotty I previously found that corruption, or zero byte files occurs with certain Nvidia encoder settings.

The cutoff was ~ 70 Mbps, below which you might not have an issue. I always use a preset of HQ and a RC mode of Vbr HQ to avoid those issues, and I can then render up to very much higher Mbps values.

ccscotty wrote on 10/6/2020, 10:44 AM

@ccscotty I previously found that corruption, or zero byte files occurs with certain Nvidia encoder settings.

The cutoff was ~ 70 Mbps, below which you might not have an issue. I always use a preset of HQ and a RC mode of Vbr HQ to avoid those issues, and I can then render up to very much higher Mbps values.

Much appreciated. I'll have to try that out!

j-v wrote on 10/6/2020, 11:19 AM

@ccscotty
Do you use default settings for the Options/Preferences or did you change settings, if yess which ones?
And are you able to show here the settings at Options/Preferences/File I/O?

ccscotty wrote on 10/7/2020, 5:25 PM

@ccscotty
Do you use default settings for the Options/Preferences or did you change settings, if yess which ones?
And are you able to show here the settings at Options/Preferences/File I/O?

I haven't changed anything in Options/Preferences/File I/O. I'm using none of the legacy options. GPU settings are all default.

The one thing I do have is the video preview RAM buffer set at 1024 instead of 200. I'd think that's unrelated to exporting videos.

From my experience, this appears to be a long standing issue with the NV encoder at higher bitrates and large images. I haven't experimented with JN's settings yet, but it sounds like he got around the issue partly.

j-v wrote on 10/8/2020, 4:12 AM

video preview RAM buffer set at 1024 instead of 200. I'd think that's unrelated to exporting video

Do you use that RAM preview from the Tools (Shift+B) very often?
If not try to set in Video Acceleration the amount to o and try again.