Quantcast Bad image quality due to hardware? What can be solved digitally? - digitalFAQ Forum
Go Back    Forum > Digital Video > Video Project Help > Capture, Record, Transfer

Reply
 
LinkBack Thread Tools
  #1  
02-04-2020, 02:34 PM
CDM Uruguay CDM Uruguay is offline
Free Member
 
Join Date: Feb 2020
Posts: 2
Thanked 0 Times in 0 Posts
Hi everyone, this is a first post. Thanks in advance for your time and for everything that has already been written in this site, which is outstanding.

We're an archival institution and we're starting to work with VHS digitalization. Our current setup (not a decent one, I know) is the following:
- Panasonic NV-FJ610 PAL-N/NTSC VHS VCR
- Elgato video capture card
- HP laptop; Intel core i5; 8 GB RAM; Win 10 Pro 64 bits
- Virtualdub 1.10.4 capture software


Attached are two examples of recent captures.

I can see a lot of problems in the digitized material: horizontal lines (kind of "jagged" borders, interlace artifact?) that are more noticeable with movement; color (¿red?) "bursts" that are very noticeable in skin tone; some kind of chromatic aberration noticeable in the guitar frets; noisy shadows (in the background curtain), etc.

So, I would like to ask you:

1- What are those problems observed?
2- Which of those problems are hardware related and which are related to other motives (VHS condition, original recording/re-recording, etc)?
3- Finding proper hardware is not easy, and it is even more difficult in my country. So, can we improve the capture results in any way with our current setup? (We will keep searching for better hardware in the meantime).
4- Can we improve those results with digital processing?

Thanks again, and congratulations on your work.


Attached Files
File Type: 7z PAL-N VHS Virtualdub capture example 1.7z (71.04 MB, 7 downloads)
File Type: 7z PAL-N VHS Virtualdub capture example 2.7z (73.61 MB, 6 downloads)

Last edited by CDM Uruguay; 02-04-2020 at 03:17 PM.
Reply With Quote
Someday, 12:01 PM
admin's Avatar
Ads / Sponsors
 
Join Date: ∞
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
  #2  
02-04-2020, 03:56 PM
themaster1 themaster1 is offline
Free Member
 
Join Date: Feb 2011
Posts: 213
Thanked 37 Times in 32 Posts
note: for PAL-N VHS Virtualdub capture example 1.avi only, i haven't checked the other.

it looks like a combination of artifacts to me: 1) oversaturation , 2) chroma noise 3) Y/C crosstalk

A good site to assist you on video artifacts (with pictures examples and solutions) can be found HERE (AV Artifact Atlas)

the 1) & 2) can be fixed with an avisynth script (it'll not be better than a good TBC or dvd recorder imo)
For the 3) i think F1Quiver (avisynth filter) can fix that
Code:
AVISource("PAL-N VHS Virtualdub capture example 1.avi")
assumetff()
# REMOVE CHROMA NOISE  (SPATIAL AND TEMPORAL)
ConvertToYV16(interlaced=true)
orig=last
ev=orig.assumetff().separatefields().selecteven()
od=orig.assumetff().separatefields().selectodd()
ev
ue_chroma = UToY(ev).blur(0,1.5).binomialblur(5).ttempsmooth(maxr=6,lthresh=150, strength=6).KNLMeansCL(d=3,a=8,s=2,h=6)
ve_chroma = VToY(ev).blur(0,1.5).binomialblur(5).ttempsmooth(maxr=6,lthresh=150, strength=6).KNLMeansCL(d=3,a=8,s=2,h=6)
YToUV(ue_chroma, ve_chroma)
MergeLuma(ev)
ev_filtered=last
od
uo_chroma = UToY(od).blur(0,1.5).binomialblur(5).ttempsmooth(maxr=6,lthresh=150, strength=6).KNLMeansCL(d=3,a=8,s=2,h=6)
vo_chroma = VToY(od).blur(0,1.5).binomialblur(5).ttempsmooth(maxr=6,lthresh=150, strength=6).KNLMeansCL(d=3,a=8,s=2,h=6)
YToUV(uo_chroma, vo_chroma)
MergeLuma(od)
od_filtered=last
interleave(ev_filtered,od_filtered)
assumefieldbased().assumetff().weave()
converttoyv12(matrix="Rec601",interlaced=true)
tweak(sat=0.8,coring=false) # FIX OVERSATURATION
QTGMC( "fast", TR0=1, TR1=1, TR2=1, EdiThreads=4) #  TO DEINTERLACE
SelectEven() ##  TO DEINTERLACE / keep normal frame rate
before/after
Reply With Quote
  #3  
02-04-2020, 04:49 PM
traal traal is offline
Free Member
 
Join Date: Jan 2016
Posts: 70
Thanked 13 Times in 11 Posts
Some aggressive temporal smoothing would also help a lot.

I see some strange periodic horizontal noise, I wonder if the VCR needs to be recapped? There's also some horizontal jitter, you'll need a VCR with line TBC to fix that, unless again bad capacitors in your VCR are causing it. Could you try another VCR and see if you get the same results?
Reply With Quote
  #4  
02-04-2020, 05:59 PM
sanlyn sanlyn is offline
Premium Member
 
Join Date: Aug 2009
Location: N. Carolina and NY, USA
Posts: 3,565
Thanked 1,134 Times in 925 Posts
Thank you for the samples.

1. Your video samples have been converted to RGB32. If you had saved them properly as YUY2, they would each be less than 70 MB in size. See How to make lossless samples. If you are capturing to RGB32, please note that it's not recommended for VHS.

2. Don't waste time and money on Elgato. If you went to a website that suggested Elgato, don't go there any more.

3. Interlace artifacts? Do you mean interlace combing? Computer monitors and PC video editors don't deinterlace, PC media players do, and TV and set-top players.

4. Unless this is badly damaged tape or a poor player, you should not see chroma flicker, distorted color, herringbone noise, or dot crawl.

5. Over saturated red, orange, yellow. It can be fixed in post processing, but converting to RGB32 without proper YUV controls makes it look worse.

6. There's a lot of seriously bad horizontal ripple in the samples. If your player has a line tbc, it isn't doing anything. If you don't have a line tbc either built-in or as pass-thru, I'm afraid you're going to need one. A line-levl tbc is not optional with VHS. It's a basic requirement.

Cleaning up VHS captures should not be this much work.

I'm sorry to say I don 't have the slightest idea why your example #2 is monochrome.

Last edited by lordsmurf; 02-05-2020 at 11:47 PM. Reason: Cleaned up post, keep it courteous and professional.
Reply With Quote
  #5  
02-04-2020, 09:37 PM
msgohan msgohan is offline
Free Member
 
Join Date: Feb 2011
Location: Vancouver, Canada
Posts: 1,084
Thanked 235 Times in 207 Posts
I think a lot of these video issues could be fixed with an appropriate line TBC passthrough.

Audio
Clip 1: The clicks in the Hi-Fi audio are troublesome. The click at 0:05 happens at the same time as a video dropout, so I guess that's the cause of it.
Clip 2: Linear audio.

Quote:
Originally Posted by sanlyn View Post
I'm sorry to say I don 't have the slightest idea why your example #2 is monochrome.
I can't tell if this is a joke. Except for the blue logo @ top right, it's very, very under-saturated. But it's certainly in color.
Reply With Quote
  #6  
02-05-2020, 11:37 AM
josem84 josem84 is offline
Free Member
 
Join Date: Feb 2019
Posts: 101
Thanked 16 Times in 16 Posts
Quote:
Originally Posted by sanlyn View Post
3. Interlace artifacts? Do you mean interlace combing?
Do not assume that everybody posting on this site is a video pro...?
Not everybody knows what interlacing is...

Last edited by lordsmurf; 02-05-2020 at 11:47 PM. Reason: Cleaned up post, keep it courteous and professional.
Reply With Quote
The following users thank josem84 for this useful post: hodgey (02-05-2020)
  #7  
02-05-2020, 12:22 PM
sanlyn sanlyn is offline
Premium Member
 
Join Date: Aug 2009
Location: N. Carolina and NY, USA
Posts: 3,565
Thanked 1,134 Times in 925 Posts
Quote:
Originally Posted by josem84 View Post
not everybody knows what interlacing is...
Sorry for the misunderstanding.
Computers and PC monitors are 100% progressive hardware.
Many people are familiar with progressive PC's nature but sometimes forget to take notice of it.

An interlaced frame contains two different images from two instances in time. When the interlaced frame is played on a deinterlacing device, each frame is separated and is displayed at two different instances. On hardware that does not deinterlace, you will see both images at the same time in the same frame. The reason you don't usually see interlaced combing on internet websites like YouTube is because interlaced video isn't allowed on the internet because, for one thing, internet players can't deinterlace. The reason you sometimes do not see interlace combing when using a PC media player or DVD player is because many media players do properly deinterlace if they detect interlaced video.

If you don't understand interlacing, I can appreciate that. The internet has thousands of free websites that explain and illustrate it. Our original capture guide also explains it, in the article "Understanding Your Source".

Most readers here are not professionals, including myself.

Last edited by lordsmurf; 02-05-2020 at 11:47 PM. Reason: Cleaned up post, keep it courteous and professional.
Reply With Quote
  #8  
02-05-2020, 12:25 PM
josem84 josem84 is offline
Free Member
 
Join Date: Feb 2019
Posts: 101
Thanked 16 Times in 16 Posts
Quote:
Originally Posted by sanlyn View Post
If you don't understand interlacing,
I know what interlacing is... you should quote the OP and explain that to him.

Last edited by lordsmurf; 02-05-2020 at 11:47 PM. Reason: Cleaned up post, keep it courteous and professional.
Reply With Quote
  #9  
02-05-2020, 01:04 PM
sanlyn sanlyn is offline
Premium Member
 
Join Date: Aug 2009
Location: N. Carolina and NY, USA
Posts: 3,565
Thanked 1,134 Times in 925 Posts
Sorry, the way your post was written I assumed you didn't know what interlace was. If I mistook your meaning, I stand corrected. I think the OP can get more information from my post.
Reply With Quote
  #10  
02-05-2020, 01:17 PM
CDM Uruguay CDM Uruguay is offline
Free Member
 
Join Date: Feb 2020
Posts: 2
Thanked 0 Times in 0 Posts
Thanks "themaster1", "traal", "msgohan" and "josem84" for your promt and constructive responses.
Reply With Quote
  #11  
02-05-2020, 11:56 PM
admin's Avatar
admin admin is offline
Site Staff | Web Development
 
Join Date: Jul 2003
Posts: 4,364
Thanked 593 Times in 440 Posts
Quote:
Most readers here are not professionals, including myself.
BTW, the OP is a professional, it was literally his/her username:
CDM Uruguay (Centro Nacional de Documentación Musical Lauro Ayestarán), www.cdm.gub.uy

They apparently primarily deal with film sources. And are they are moving into VHS work, which is the reason for this thread.

And as such, he/she should be extended professional decorum. Unnecessary comments and banter have therefore been removed, those posts edited.

While disagreements on the site are fine, you must refrain from doing so with excessive snark.

Also remember that members ask questions because they do not know the answers. And this is why the forum is here. Questions (posts) are encouraged. After many years of Q&A, this site has literally become an FAQ for video/photo/web, as our name suggests (The Digital FAQ). Sometimes members even assume they know something, and must be corrected. All of this should happen within the confines of amicable discussions, not using words that chastise or mock. Certainly not with language that would make members feel unwelcome.

See also: Forum Rules

Thanks, and carry on.

- Did this site help you? Then upgrade to Premium Member and show your support!
- Also: Like Us on Facebook for special DVD/Blu-ray news and deals!
Reply With Quote
The following users thank admin for this useful post: BW37 (02-06-2020)
Reply




Tags
bad image quality, capture problems, elgato, virtualdub

Similar Threads
Thread Thread Starter Forum Replies Last Post
VCR PSU effect on image quality? HBB360 Video Hardware Repair 1 08-12-2019 05:31 PM
Image quality: Panasonic NV-HS1000 vs. NV-HS960B? heym56 General Discussion 7 02-21-2016 05:19 AM
Cruddy Image Quality with HD Camcorder in Low Light Stuations rocko Videography: Cameras, TVs and Players 4 11-21-2013 12:54 AM
Wanted: Any PAL compatible device to help image/picture quality (IQ/PQ) Mejnour Marketplace 0 01-10-2012 07:56 PM
Best BETA VCR for image quality? lordsmurf Capture, Record, Transfer 6 02-29-2008 04:30 AM

Thread Tools



 
All times are GMT -5. The time now is 01:55 AM