Capture Codec Setting, Crushed Black Levels, Histogram use

[Smells_Like_Feet]

I've struggled over the years understanding how to properly capture VHS footage and convert it into dvd compliant video without crushing black levels. Please see my basic work flow below and confirm or correct my errors:

Capture Hardware = Hauppauge WinTV-HVR-2250
OS = Windows 10
Video Source = Commercial NTSC VHS
Playback Device = JVC DVHS HM-DH40000U

Capture Software = VirtualDub2 64bit
Codec used: UtVideo T2 YUV422 BT.601 VCM
Codec Settings: 720 x 480 YUY2 YUV 4:2: interleaved

Basic workflow:
1. Scan the video for a short portion and attempt to adjust the capture LEVELS within VDub utilizing the built-in histogram.
2. Capture files and monitor for dropped frames
3. Import captured video into Vegas Pro 17.
4. Apply black mask to hide lower scan lines
5. Apply filters (usually just NEAT video filter)
6. Output video to mpeg2 @ 720 x 480

Specific questions:
1. When working in Vegas, if I review the video with the VEGAS built in Histogram, should I engage the setting "7.5 IRE Setup" (default is off)? How about the setting "Studio RGB" (default is on)?
2. I'm concerned that there are some color space conversion issues with my capture method. It seems that everything looks pretty good within the Vegas preview window, but when I export my finished video, the black levels become crushed. Is there anything I'm doing that could be a likely cause of crushed black levels?
3. Regarding the imported video, I've noticed that I need to set my video properties Pixel Aspect Ratio to .9091 (NTSC DV) or else the image is distorted slightly. Does this make sense? I'm not working with a DV camera.


Thanks for looking and any advice you can give.

- Smells_Like_Feet

[Eric-jan]

You should mention your PC hardware, which is also very important.
do you capture files to SSD m.2 storage ?

[Smells_Like_Feet]

Thanks for the suggestion. My PC rig is a recently completed build:

AMD Ryzen 3950X
MSI Prestige X570 Creators Motherboard
System Drive: Samsung 970 EVO PLUS SSD m.2
Storage Drive (Capture Drive): White label WD 10TB (SATA 6)
RAM: 64 GB GSKILL


Any suggestions is appreciated.

[poisondeathray]

This is very likely a user / Vegas issue

You have to read up on Computer RGB and Studio RGB with vegas. Many of the articles are from Sony vegas, but they should still apply. Look up Glenn Chan and Sony Vegas


The short version - Normally, vegas treats YUV assets from typical sources as "Studio RGB" . Studio RGB is it's default operation .

But most "lossless" YUV codecs get converted to computer RGB range instead of studio RGB range. The difference is a contrast expansion for computer RGB. You want to be looking at waveform, not the histogram. It's easier to see what is going on. This is why things look clipped on both ends

=> A workaround if you are using this type of workflow is to apply a levels preset before you export, Computer RGB to Studio RGB preset

1. When working in Vegas, if I review the video with the VEGAS built in Histogram, should I engage the setting "7.5 IRE Setup" (default is off)? How about the setting "Studio RGB"
(default is on)?

Normally no for 7.5IRE , Normally yes for Studio RGB

2. I'm concerned that there are some color space conversion issues with my capture method. It seems that everything looks pretty good within the Vegas preview window, but when I export my finished video, the black levels become crushed. Is there anything I'm doing that could be a likely cause of crushed black levels?

see above; it's just the way vegas handles certain formats and the settings you are using

3. Regarding the imported video, I've noticed that I need to set my video properties Pixel Aspect Ratio to .9091 (NTSC DV) or else the image is distorted slightly. Does this make sense? I'm not working with a DV camera.

Yes, it was from VHS .

[Smells_Like_Feet]

Thanks.

Should I apply the Levels filter preset Computer RGB to Studio RGB first the filter chain or at the end? Will it affect the way the Neat Video filter works?

I love this hobby, but there is so much technical know-how required.

[TimA-C]

Are there any capture codecs that he could use that Vegas handles better?

[poisondeathray]

Thanks.

Should I apply the Levels filter preset Computer RGB to Studio RGB first the filter chain or at the end? Will it affect the way the Neat Video filter works?

I love this hobby, but there is so much technical know-how required.

It partially depends on how you have your project and display(s) set up, whether or not you have mixed assets; but it should be ok eitherway

I don't use neat in vegas, but it should be ok

It's easy enough to test - just render out a 5 second loop region to verify

But if your capture had actual usable data (not noise or useless data) < Y=16 , or > Y=235 , it would be better to use magicyuv (see below) . There is a chance you could salvage some of the data . But if you captured at correct levels in the first place, it's unlikely to make a significant difference .

Are there any capture codecs that he could use that Vegas handles better?

For lossless codecs - magicyuv with the "full range yuv" option checkmarked . That's what I would use in vegas . This gets treated as "studio RGB" in vegas

[TimA-C]

Thanks PoisonDeathRay (I'm sure there must be a story behind your choice of screen name!). Do you know, can he use the free version (v1.2?) of magicyuv or would he need to purchase one of the later versions?

[poisondeathray]

Thanks PoisonDeathRay (I'm sure there must be a story behind your choice of screen name!). Do you know, can he use the free version (v1.2?) of magicyuv or would he need to purchase one of the later versions?

free version works ok for this