Frame skipping/duplication in rendered video

Cantersoft wrote on 3/28/2020, 9:00 PM

Hello,

I made a post about a rendering issue a couple months ago, but it seems a video of the problem would explain it better:

Basically, I wanted to replace part of my project with a rendered version of itself to save CPU. After I render the video, there's always a black frame at the beginning, and random frames throughout the post-rendered video are in the wrong positions.

To demonstrate this, I aligned the prerendered and post-rendered videos on separate tracks, and set the opacity of the prerendered video to 50%. If the videos were exactly the same, there wouldn't be any ghosting (visible frame difference).

For referencing purposes, here is my original request for help: https://www.vegascreativesoftware.info/us/forum/random-insertion-of-duplicate-frames-in-rendered-mp4-file--118691/

Details

Software: Vegas Pro 14.0
Processor: Intel Core i7 8th Gen
Graphics Card: Intel UHD Graphics 620
Operating System: Windows 10

Project framerate: 23.976
Rendering framerate: 23.976
Resampling: disabled on all video events and in project settings
Video format: mp4

The source footage is an animated video.

Source video: https://mega.nz/#!DRIhRQCI!HrIwSEYHCB4UAr3F0Gw99IXYn3aHr9-Ng3e9Nwm5xfc

Mediainfo report of source video:

General
Complete name                            : G:\FiM\S1\My Little Pony FiM - 1.16 - Sonic Rainboom.mp4
Format                                   : MPEG-4
Format profile                           : Base Media / Version 2
Codec ID                                 : mp42 (mp42/mp41)
File size                                : 936 MiB
Duration                                 : 22 min 2 s
Overall bit rate mode                    : Variable
Overall bit rate                         : 5 937 kb/s
Encoded date                             : UTC 2013-01-08 20:45:42
Tagged date                              : UTC 2013-01-08 20:45:42
TIM                                      : 00:00:00:00
TSC                                      : 2997
TSZ                                      : 125Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L5.1
Format settings                          : CABAC / 3 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 3 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 22 min 2 s
Bit rate                                 : 5 612 kb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 23.976 (23976/1000) FPS
Original frame rate                      : 23.976 (24000/1001) FPS
Standard                                 : NTSC
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.113
Stream size                              : 885 MiB (95%)
Language                                 : English
Encoded date                             : UTC 2013-01-08 20:45:42
Tagged date                              : UTC 2013-01-08 20:45:42
Color range                              : Limited
Color primaries                          : BT.709
Transfer characteristics                 : BT.709
Matrix coefficients                      : BT.709
Codec configuration box                  : avcCAudio
ID                                       : 2
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Codec ID                                 : mp4a-40-2
Duration                                 : 22 min 2 s
Source duration                          : 22 min 2 s
Bit rate mode                            : Variable
Bit rate                                 : 317 kb/s
Maximum bit rate                         : 417 kb/s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 46.875 FPS (1024 SPF)
Compression mode                         : Lossy
Stream size                              : 50.0 MiB (5%)
Source stream size                       : 50.0 MiB (5%)
Language                                 : English
Encoded date                             : UTC 2013-01-08 20:45:42
Tagged date                              : UTC 2013-01-08 20:45:42

Project properties:

Source file properties:

General
  Name: My Little Pony FiM - 1.16 - Sonic Rainboom.mp4
  Folder: G:\FiM\S1
  Type: AVC
  Size: 958.42 MB (981,422,726 bytes)
  Created: Monday, July 29, 2019, 10:50:12 AM
  Modified: Thursday, May 16, 2019, 3:37:20 PM
  Accessed: Saturday, March 28, 2020, 12:00:00 AM
  Attributes: ArchiveStreams
  Video: 00:22:02.364, 23.976 fps progressive, 1920x1080x12, AVC
  Audio: 00:22:02.364, 48,000 Hz, Stereo, AACACID information
  ACID chunk: no
  Stretch chunk: no
  Stretch list: no
  Stretch info2: no
  Beat markers: no
  Detected beats: noOther metadata
  Regions/markers: no
  Command markers: noMedia manager
  Media tags: noPlug-In
  Name: compoundplug.dll
  Folder: C:\Program Files\VEGAS\VEGAS Pro 14.0\FileIO Plug-Ins\compoundplug
  Format: AVC
  Version: Version 14.0 (Build 161) 64-bit
  Company: MAGIX Computer Products Intl. Co.

Render settings:

Comments

fr0sty wrote on 3/29/2020, 12:56 AM

Try using the Magix AVC codec and see if you have the same issues. If updating your GPU driver does not help, just as a test I would download the demo of Vegas 17 and render using it (that will also open up new GPU rendering options with Magix AVC that will go much faster and will likely be more reliable, the Sony AVC GPU acceleration is very dated.) Using more modern versions of Vegas, you will also have access to intel quicksync (assuming your CPU has it, which a quick glance shows the 8th gen i7's in fact do have it), which is another type of GPU acceleration that has proven to be quite fast in Vegas, especially when paired with another AMD or Nvidia GPU (one does timeline acceleration, the other decoding and rendering acceleration). That also brings up another reason to consider the upgrade, 17 also offers hardware video decoding for AVC and HEVC formats, which can lead to massive performance boosts while editing.

The only restriction on the demo is you can only render 2 minutes at a time, but that should be more than enough for you to tell if the issue persists in the newer versions.

j-v wrote on 3/29/2020, 3:39 AM

@fr0sty

Try using the Magix AVC codec and see if you have the same issues.

Vegas 14 has no Magix AVC, only MC AVC and Sony AVC for his goal.

fifonik wrote on 3/29/2020, 5:58 AM

Have you tried to find what causing the issue: the project or the encoder? You can try to create a new project, put single file onto timeline and render it. Then add rendered file in the same project (as you did) and check it out.

I'm asking as when I compared encoders I have not found such issue with Sony AVC. However, I have not done it in VP14.

BTW, I think your file IS VFR (Variable Frame Rate):

Frame rate mode                          : Constant 
Frame rate                               : 23.976 (23976/1000) FPS 
Original frame rate                      : 23.976 (24000/1001) FPS

Have you noticed Nums/Dens are different: 23976/1000 vs 24000/1001. MediaInfo rounding it out and shows as 23.976 in both casest.

vkmast wrote on 3/29/2020, 7:28 AM

@j-v fr0sty suggested downloading "the demo of Vegas 17 and render using it (that will also open up new GPU rendering options with Magix AVC" (if you go past the first sentence).

j-v wrote on 3/29/2020, 8:24 AM

(if you go past the first sentence).

Yess , but his first advice is to use the Magix codec ( that is not in the version OP has)
After that came a second suggestion to update the GPU driver and if that does not help than the third suggestion to try the upgrade to VPro 17 that has indeed the different options for Magix rendertemplates for AVC , I also always use.

Cantersoft wrote on 3/29/2020, 8:36 PM

@fifonik

I made a new project and tried rendering the source file from there. I have the same issue. I think it might be a problem with the codec then. Perhaps it wouldn't be too much trouble to try and upgrade to Vegas 17.

On the other hand, I didn't realize the source was VFR. So if this is an issue with the media itself, would I have any guarantee that upgrading would resolve the frame skipping/duplicating problem?

fr0sty wrote on 3/29/2020, 8:42 PM

Best way to tell is to download the free VP17 demo and try it out.

fifonik wrote on 3/29/2020, 9:38 PM

If this is really the VFR file, upgrading VP will not solve the issue. VP cannot render VFR file.

Unfortunately, I do not know if the file you have is VFR. Mediainfo framerate detection is really tricky and I personally never worked with 23.976 fps medias so do not even know what Mediainfo should display. May be this is absolutely correct output for such files.

I hope some other people who have such files can check it and let you know.

I'd try to find file that is CFR and test with it.

Also, you can try to follow wwaag's suggestions about using Happy Otter Import Assist to find duplicates and check for VFR that he just posted in this VFR related thread.

fr0sty wrote on 3/29/2020, 10:01 PM

VP cannot render VFR, but more recent versions of Vegas have been able to properly render VFR to a CFR file.

fifonik wrote on 3/30/2020, 2:17 AM

BTW, have you tried to enable resample? I do not know how VP work with VFR when resample is disabled.

Cantersoft wrote on 3/30/2020, 11:28 PM

@fr0sty

@fifonik

I tried using the Vegas 17 Magix AVC codec. It sort of simplified the issue-- no black frames, but the rendered video duplicates and reinserts frame 11, lengthening the video by one frame.

And using enable resample didn't seem to change anything either....

Cantersoft wrote on 3/30/2020, 11:45 PM

Moreover, I also tested with my original project in V17 again, and I guess since it has more editing there's even more wrong frames. Basically the same issue as before, just slightly not as bad.

Cantersoft wrote on 3/31/2020, 12:39 AM

Okay, I did find a solution, although it was a bit tedious. I rendered the video into an image sequence, and then re-imported the image sequence at as close of a still image length to 1/23.976 Vegas would allow, then I rerendered the image sequence into an mp4 file from Vegas and finally I reimported the mp4 into the timeline and deleted the image sequence. Unfortunately, some frames at the end of the re-rerendered video got truncated from the render, but it was only like four so it was fixable. Ugh Vegas is rather buggy in general.