Voukoder render has pixleated frames around some event transitions

dxdy wrote on 6/10/2021, 2:25 PM

I have been getting a strange error in MP4s rendered with Voukoder. (Before I go any further, I LOVE Voukoder, beautiful images, small files.)

The symptom is a brief pixelated image in the rendered file at the point the timeline transitions from one event to the next one. But it only happens about one time in 10 or 15. (There are no Vegas transitions applied; this refers to the point on the timeline where one event abuts another.)

The events are Canon MXF files from a Canon XF300, 1920 x 1080, 60p, at 50Mbps. There can be 20 events on a timeline. The events are all butted up against each other, there are no gaps.

There is the video track, and above it 3 other tracks, one with a simple legacy text that says "7 PM" with clear background, one with a single empty event with a timecode running, and one with song titles and performers' names in a Vegas Credit Roll.

VEGAS White balance FX is applied to all events.

Vegas version 18, build 527. Computer AMD Ryzen 3900X 12-core processor at 4GHz not overclocked. 8 GB memory. Source files are on an SSD. Vegas program is on a different SSD. Render output goes on an internal HDD. Running this template with these files, CPU load is over 90% and sometimes hits 100%. NVIDIA GPU is loafing.

Voukoder version 7, template: "Video: project default, Audio: project default"
"Audio: 0 Hz, 0 Channel
Video: Project Frame Rate, Project Frame Size
Pixel Aspect Ratio: 1.000"
(Note: there is audio in both the source and the rendered output, and the audio is working properly.)

The error does not occur with the Magix mp4 encoder.

I have also posted this on the Voukoder forum.


Medianinfo for input files:
General
Complete name                     : L:\Coppelia2021\CopelliaSat7pm\AA1516\AA151602.MXF
Format                                   : MXF
Commercial name                  : XDCAM HD422
Format version                       : 1.2
Format profile                         : OP-1a
Format settings                       : Closed / Complete
File size                                : 1.91 GiB
Duration                                 : 5 min 13 s
Overall bit rate                         : 52.2 Mb/s
Encoded date                          : 2021-06-05 20:09:55.000
Writing application                  : CANON XF300 1.00

Video
ID                                       : 2
Format                                   : MPEG Video
Commercial name                 : XDCAM HD422
Format version                      : Version 2
Format profile                         : 4:2:2@High
Format settings                      : CustomMatrix / BVOP
Format settings, BVOP          : Yes
Format settings, Matrix          : Custom
Format settings, GOP             : M=3, N=15
Format settings, wrapping mode           : Frame
Codec ID                                 : 0D01030102046001-0401020201040300
Duration                                 : 5 min 13 s
Bit rate mode                           : Constant
Bit rate                                 : 50.0 Mb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                  : 16:9
Frame rate                               : 29.970 (30000/1001) FPS
Standard                                 : Component
Color space                             : YUV
Chroma subsampling              : 4:2:2
Bit depth                                : 8 bits
Scan type                                : Progressive
Compression mode                 : Lossy
Bits/(Pixel*Frame)                    : 0.805
Stream size                              : 1.83 GiB (96%)
Color range                              : Limited
Color primaries                         : BT.709
Transfer characteristics             : BT.709
Matrix coefficients                      : BT.709

Audio #1
ID                                       : 3
Format                                   : PCM
Format settings                          : Little
Format settings, wrapping mode           : Frame (AES)
Codec ID                                 : 0D01030102060300
Duration                                 : 5 min 13 s
Bit rate mode                            : Constant
Bit rate                                 : 768 kb/s
Channel(s)                               : 1 channel
Sampling rate                            : 48.0 kHz
Frame rate                               : 29.970 FPS (1601.6 SPF)
Bit depth                                : 16 bits
Stream size                              : 28.7 MiB (1%)
Locked                                   : Yes

Audio #2
ID                                       : 4
Format                                   : PCM
Format settings                          : Little
Format settings, wrapping mode           : Frame (AES)
Codec ID                                 : 0D01030102060300
Duration                                 : 5 min 13 s
Bit rate mode                            : Constant
Bit rate                                 : 768 kb/s
Channel(s)                               : 1 channel
Sampling rate                            : 48.0 kHz
Frame rate                               : 29.970 FPS (1601.6 SPF)
Bit depth                                : 16 bits
Stream size                              : 28.7 MiB (1%)
Locked                                   : Yes

Other #1
ID                                       : 1-Material
Type                                     : Time code
Format                                   : MXF TC
Frame rate                               : 29.970 (30000/1001) FPS
Time code of first frame                 : 09:31:09;18
Time code settings                       : Material Package
Time code, striped                       : Yes

Other #2
ID                                       : 1-Source
Type                                     : Time code
Format                                   : MXF TC
Frame rate                               : 29.970 (30000/1001) FPS
Time code of first frame                 : 09:31:09;18
Time code settings                       : Source Package
Time code, striped                       : Yes

Other #3
Type                                     : Time code
Format                                   : SMPTE TC
Muxing mode                              : SDTI
Frame rate                               : 29.970 (30000/1001) FPS
Time code of first frame                 : 09:31:09;18

Comments

Musicvid wrote on 6/10/2021, 6:16 PM

Post MedIaInfo for the Voukoder output file.

dxdy wrote on 6/10/2021, 7:01 PM

Here it is:

Medianfo for output files:
General
Complete name                            : G:\Render\Coppelia2021_2pm\Copellia2021Sat2pmDraft2.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/avc1/mp41)
File size                                : 2.74 GiB
Duration                                 : 1 h 31 min
Overall bit rate mode                    : Variable
Overall bit rate                         : 4 301 kb/s
Writing application                      : Voukoder (VEGAS)

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4
Format settings                          : CABAC / 4 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 4 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 1 h 31 min
Bit rate                                 : 4 165 kb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 29.970 (30000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.067
Stream size                              : 2.66 GiB (97%)
Writing library                          : x264 core 157 r2981 b5bc5d6
Encoding settings                        : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=34 / lookahead_threads=5 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=23.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Codec configuration box                  : avcC

Audio
ID                                       : 2
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Codec ID                                 : mp4a-40-2
Duration                                 : 1 h 31 min
Duration_LastFrame                       : -20 ms
Bit rate mode                            : Variable
Bit rate                                 : 128 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                              : 83.1 MiB (3%)
Default                                  : Yes
Alternate group                          : 1


M

Musicvid wrote on 6/10/2021, 7:44 PM

In the Voukoder x264 Video Options, try crf=20 instead of 23. This will cause a bigger file.

If that doesn't clear it up completely, set vbv-maxrate and vbv-bufsize as shown. This will raise your effective minimum bitrate without hurting peak motion.

 

 

dxdy wrote on 6/11/2021, 8:53 AM

Aha! I will give it a try. Thank you.

Howard-Vigorita wrote on 6/11/2021, 1:37 PM

@dxdy I've experienced that exact issue with mxf footage from my xf305 with Magix render templates. I don't think it's a Voukoder issue. In my case it only occurred on the camera clip splits on the timeline and only in a random manner more than a half hour into continuous shoots with splits every 5 minutes. My theory is that it's a Vegas buffer management issue. In any event, my cure has been to glue all the camera splits into one long clip using the ffmpeg concat filter. I think HOS has a similar facility which you might prefer if you don't have ffmpeg installed somewhere on your search path.

I thought I posted the ffmpeg solution once before but apparently not. It's a 2-step process. First I drop a copy of this windows batch file I call "mfx_list.cmd" into the folder holding the MFX camera clips to join together and double-click on it to run it:

(for %%i in (*.mxf) do @echo file '%%i') | sort > mxf_list.txt

It creates a file named "my_list.txt" that you can edit with notepad in case there are clips in the folder you don't want glued into the output file.

Then I drop a copy of this windows batch file into the same folder and run it. I call it "mxf_cat.cmd":

ffmpeg -f concat -i mxf_list.txt -c:v copy -c:a copy -map 0:v:0 -map 0:a:0 -map 0:a:1 mxf_cat.mxf

It reads the text-file list and emits a glued clip named "mxf_cat.mxf". Note that this script is specific to my xf305's mxf format that contains 2 mono audio streams for L and R. I see from your mediainfo yours is the same.

dxdy wrote on 6/12/2021, 7:06 AM

Howard-Vigorita: Thank you. You have described my conditions exactly. To support your thoughts about a Vegas buffer, if I go to the camera clip split that gave me a problem, set a region around it of several minutes, render it with same settings, the problem does not occur. This pixelation is a recent development. I have been using the XF300 for years, merely copying the MXF files off the card and onto an internal SSD, and then dragging them into Vegas. I have enough fussy users that they would have complained loudly and not a single one has.

Howard-Vigorita wrote on 6/12/2021, 1:38 PM

Fwiw, I first started seeing the problem in VP17, but only for continuous shoots over around a half hour. Got into the practice for a while of playing through the boundaries where clips abut and dropping markers where they show pixelation... which actually seem to be pixels from a partial frame elsewhere in the project which is why I think it's a buffer thing. Playing through the markers before doing a render makes it go away. Joining the clips has worked better for me with the added benefit that Vegas behaves better in multicam edit without clip splits. So does the v18 grading panel which is clip-oriented.

Btw, I just studied your mediainfo more closely and notice that your Voukoder render converts to 420 color... makes a smaller file but throws away the actual color depth captured by your camera. It's triple ccd sensor array which captures full rgb, albeit down-converting it to 422, is what makes that camera so special. Cameras these days tend to only have a single 420 sensor and get phony-422 by up-converting.

dxdy wrote on 6/14/2021, 12:32 PM

Howard-Vigorita, thank you again. Do you know if there is a way to keep it from downgrading from 422 to 420? The tiny files are great for drafts, but for the final I would like the best I can get.

RogerS wrote on 6/14/2021, 12:48 PM

If it's the final render I think 420 is the most appropriate for delivery. If you want a pristine master, render to ProRes, too.

Howard-Vigorita wrote on 6/14/2021, 3:09 PM

@dxdy To keep your 422 in the render with AVC using Voukoder you need to choose the x264 (ffmpeg lib) encoder. It's in the Pixel Format drop-down at the top. The x265 lib also has it. As mentioned above, all the ProRes formats are 422 too. If you go through all the pain of editing 422 (it's bigger, can't be decoded in hardware, and its slower to render, even to 420 in hardware)... you might as well deliver the fruits of your labor.

dxdy wrote on 6/16/2021, 6:24 PM

I wonder if the 422 input format is contributing to the buffer issue.