digitalFAQ.com Forum

digitalFAQ.com Forum (https://www.digitalfaq.com/forum/)
-   Capture, Record, Transfer (https://www.digitalfaq.com/forum/video-capture/)
-   -   DV vs. SDI based video capture workflow ? (https://www.digitalfaq.com/forum/video-capture/12778-dv-vs-sdi.html)

mrwassen 05-18-2022 04:10 PM

DV vs. SDI based video capture workflow ?
 
Hi guys,

I was hoping to get some feedback on 2 video capture workflow options which I have available and have described below. The subject of the workflow are various PAL home movie tapes belonging to friends and family. I will later be doing some NTSC too, but for now I am focusing on PAL.

I realize the 7500 does not have an onboard TBC, so I plan to get hold of a 7860 in the near future which does.

I also have a ADVC-110 available which does a nice job, but am unable to regulate audio volume on the device, hence using the ADVC-3000 which I picked up some years ago at a reasonable price. (The tapes have a wide variety of audio levels and it is nice to be able to calibrate this).

DV Option
=========
JVC HR-S7500EK >
<S-video / RCA audio>
ADVC-3000 >
<DV2 4 pin>
PCIe Firewire card
Capture software = Scenalizer (>avi)
Post capture editing = Vegas Pro v.16
Render mp4 / h264

Decklink Option
===============
JVC HR-S7500EK >
<S-video / RCA audio>
ADVC-3000 >
<SDI output via BNC cable>
Blackmagic DeckLink Mini Recorder 4K PCIe Card
Capture software = OBS studio (>mkv)
Post capture editing = Vegas Pro v.16
Render mp4 / h264

Also, any thoughts on the value of using ADVC-3000 vs the ADVC-110? The quality coming out of the 3000 seems really good but I have not really done any direct compares with the 110 output as of yet.

Any advice/ideas/guidance would be much welcome.

Thanks

Dennis

latreche34 05-18-2022 10:24 PM

I've been in a lookout for an ADVC-3000 to add to my equipment for years I've yet to find one for a reasonable price, Anyway make sure the ADVC-3000 is used in analog to SDI mode, no DV crap. Also make sure your SDI interface (the BM decklink) is capable of SMPTE 259M-C rec.601, that's the right standard for digital video signal originated from analog video sources, not 480p or some other weird HD/4K settings, Don't use OBS, use MediaExpress and output YUV2 8bit lossless AVI, encode later.

Alternatively if the decklink has a Y/C analog input try it instead of the ADVC-3000 and compare the two results, though it will not have a frame TBC like the ADVC-3000.

I'm not sure about Vegas pro, I don't use such software.

You don't need the ADVC-110.

mrwassen 05-19-2022 12:52 AM

3 Attachment(s)
Hi Latreche,

Thanks for your input, this is helpful. I have attached my ADVC-3000 and BM Media Express Setup. I don't see the exact options you listed in the BM Media Express, but I tried to get as close as possible.

The display on the ADVC-3000 regarding the video side of things is not very clear, but the connection is S-video from VCR to ADVC-3000 and RCA audio from the VCR to "unbalanced" audio in (channel 1 and 2) on the 3000. The output from the 3000 is SDI port to the BM Decklink card using a BNC cable.

The reason I have avoided the BM Media Express software is that there is no way to time limit the capture, so even with my beefy SSD partition I could run out of space if I leave the capture unattended (to get some z's for example). (OBS does have that feature and supports the card as source input.).

I would like to keep the 3000 in the equation as it seems to eliminate or at least limit audio out of sync conditions which often seem to occur when capturing mediocre material with jumpy sequences etc.

Just out of curiosity (bearing in mind that I am relatively new to all of this), could you please provide a few bullets on your concerns with going the DV route?

Thanks in advance,

Dennis

hodgey 05-19-2022 04:05 AM

If BM express doesn't allow the needed functionality (also I don't get why it still doesn't allow use of windows codecs or at least prores like on macos), amarectv or virtualdub may work. Alternatively one can use ffmpeg but that may be a bit clunky (I think there are some other open source BM card specific softwares too but can't find it right now.)

If you use OBS you have to be really careful with color space and resolution settings to avoid any unwanted conversions and it messing with the image at least. Capturing

latreche34 05-19-2022 04:29 AM

Quote:

Originally Posted by mrwassen (Post 84830)
Thanks for your input, this is helpful. I have attached my ADVC-3000 and BM Media Express Setup. I don't see the exact options you listed in the BM Media Express, but I tried to get as close as possible.

625i/50 AVI YUV 4:2:2 10bit 270 Mbit/s when carried over SDI is exactly SMPTE 259M-C, The reason to capture 8bit is that script software don't work with 8bit files, if you use NLE you can go 10bit.

Quote:

Originally Posted by mrwassen (Post 84830)
The reason I have avoided the BM Media Express software is that there is no way to time limit the capture, so even with my beefy SSD partition I could run out of space if I leave the capture unattended (to get some z's for example). (OBS does have that feature and supports the card as source input.).

Even if you enable "stop capture if dropped frames are detected"? This should take care of it when the tape reaches the end, Unless the TBC inside the ADVC-3000 keeps supplying a clean frame sync signal even with no video. Otherwise just use vdub or AmarecTV.

Quote:

Originally Posted by mrwassen (Post 84830)
I would like to keep the 3000 in the equation as it seems to eliminate or at least limit audio out of sync conditions which often seem to occur when capturing mediocre material with jumpy sequences etc.

Yes, because it has a full frame TBC.

Quote:

Originally Posted by mrwassen (Post 84830)
Just out of curiosity (bearing in mind that I am relatively new to all of this), could you please provide a few bullets on your concerns with going the DV route?

DV is lossy and have half the chroma info for both NTSC (horizontally) and PAL/SECAM (vertically) compared to 4:2:2, And when converted to h.264 or any modern codec that's another loss you will have to deal with, AVI 4:2:2 is as lossless as you can get from an analog video source.

dpalomaki 05-19-2022 07:40 AM

Quote:

...but am unable to regulate audio volume on the device...
Adding a modest cost audio mixer is an approach to solving this.

The DV signal has adequate bandwidth (frequency response) to capture the resolution of VHS/S-VHS/Video8/Hi8 including the color under recording output (which is very crippled). However, it uses lossy compression and that results in issues for subsequent restoration, especially with home videos that typically have a lot of noise that waste bits in the compression scheme.

RobustReviews 05-19-2022 10:52 AM

SDI is great, and often overlooked.

We do use DV sometimes for domestic videos, PAL is perfectly passable and still considerably better than most cheapo methods - NTSC looks pretty dire though.

When you account for the placebo of knowing about the lossy compression, A/B with DV vs. AN Other capture methods with PAL isn't tremendously noticeable. It's not as good, but it's not the huge casm encountered with DV-NTSC captures.

Decent DV units with PAL can look perfectly adequate, are they the best? No, are they cheap enough and practical - yes. They're still an order better than cheap USB sticks or no-name cards though.

SDI is my preferred route at the moment, but they're all tools in the box.

lordsmurf 05-19-2022 12:21 PM

Quote:

Originally Posted by cafecafe (Post 84823)
Hfrom globalmediapro

You have to be really careful with GMP. Very often, what they advertise/claim to have, and what they actually have, is not the same thing. Ask questions. If they don't know, don't buy.

Quote:

Originally Posted by RobustReviews (Post 84841)
When you account for the placebo of knowing about the lossy compression, A/B with DV vs. AN Other capture methods with PAL isn't tremendously noticeable. It's not as good, but it's not the huge casm encountered with DV-NTSC captures.

The main betrayer is always blocks.

Slight fuzzy image, due to chroma smearing, but it can be tolerable like DVDs. The ingest quality matters, source tape matters. Make or break. It's more obvious as screen size increases, such as viewed on typical large HDTV.

Colors can be hot, on both PAL and NTSC. Chroma processing is often to blame. Saturation is not pumped, but it can seem that way. NTSC colors are cooked, but the PAL is more nuanced.

PAL and NTSC both have a "DV look" to them, what was referred to as a "digital look" before Youtube/etc existed.

RobustReviews 05-19-2022 12:59 PM

Quote:

Originally Posted by lordsmurf (Post 84843)
The main betrayer is always blocks.

Slight fuzzy image, due to chroma smearing, but it can be tolerable like DVDs. The ingest quality matters, source tape matters. Make or break. It's more obvious as screen size increases, such as viewed on typical large HDTV.

Colors can be hot, on both PAL and NTSC. Chroma processing is often to blame. Saturation is not pumped, but it can seem that way. NTSC colors are cooked, but the PAL is more nuanced.

PAL and NTSC both have a "DV look" to them, what was referred to as a "digital look" before Youtube/etc existed.

You're not wrong, I stand by that it's far from unacceptable with PAL though. Most digitised video in my opinion looks digitised to one degree or another? Do you agree?

The below shouldn't be conflated with what is technically correct, and is simply descriptive:

The majority of our work for domestic customers is being transcoded to downloaded for mobile devices though, the small screen for us is technically our target. More customers now request stream/transcode options as opposed to straight files as having the videos 'to hand' on a mobile device or tablet is actually more useful for them than watching in the living room. 40% of our domestic customers in the first quarter of 2022 solely wanted mobile streaming options.

That's a sample of one business in one market, however. I have an ET bill to prove where most of our media is being consumed. Here at least, 'big screen' living room viewing is boomer behaviour, I don't know how it's going in the US but broadcast television (which I know is not the same) but as a broad pattern under-30s here consume little broadcast TV. I can't really draw a parallel between the age of customers and the media they're consuming it on as even some very mature customers are more concerned with having their precious memories on their smartphone than consuming in front of the TV.

These are very broad statements, but for the non-enthusiast or professional I wonder if we've crossed the line with this, and it's actually going to make less sense to worry about large screen quality in the next few years?

I've dubbed cassettes for the car this afternoon though, so diff'rent strokes 'n' all.

TL;DR - Customers who watch converted videotape on 'actual' televisions are diminishing by our sales information.


To 'circle back' as one famous US press secretary likes to say, give the 110 a go for comparison, they're far from a bad little unit if you accept their limitations.

lordsmurf 05-19-2022 01:49 PM

Quote:

Originally Posted by RobustReviews (Post 84844)
You're not wrong, I stand by that it's far from unacceptable with PAL though. Most digitised video in my opinion looks digitised to one degree or another? Do you agree?

Usually, yes. Some more than others. Most more than not. It takes multiple factors colliding just right to look still look analog.

Quote:

More customers now request stream/transcode options as opposed to straight files as having the videos 'to hand' on a mobile device or tablet is actually more useful for them than watching in the living room. 40% of our domestic customers in the first quarter of 2022 solely wanted mobile streaming options.
Interesting. Most of ours are lossless requests. Maybe lossless + deimterlaced streaming copy for immediate watching, while they continue to edit, restore, and otherwise process their final copies. The MKV version helps with their project, easy preview. But quite a few are business level customers: archives, indy filmmakers, etc. Though home users, too.

Quote:

'big screen' living room viewing is boomer behaviour, I don't know how it's going in the US
I always cringe when I see that term. My response is always "alright kid". (I'm GenX, don't call me a Boomer. And we invented attitude, you little welp. :laugh:)

I guess that's just your customer demographic? As you Brits would say, you seem to have a lot of mouthy prats as customers, if that's really the words they use.

Quote:

but broadcast television (which I know is not the same) but as a broad pattern under-30s here consume little broadcast TV. I can't really draw a parallel between the age of customers and the media they're consuming it on as even some very mature customers are more concerned with having their precious memories on their smartphone than consuming in front of the TV.
That is interesting. I think this is a case of stereotypes being accurate. "Fat lazy Americans" = couch potatoes = sit and watch TV. After all, we invented the term "Netflix and chill".

Around here, it's mostly only the youngest (and non-customer) Tiktok/Z generation that watches phones. And they will probably grow out of that, as eyesight fails you as early as 30s, definitely by 40s.

Audio also matters to many. I sometimes watch stuff on my tablet, but not anything long, as even the "good" speakers on my higher-end Samsung tablet suck compared to my TV, or even our non-work computer.

UK may especially have a gripe about TV, due to BBC. Taxes, social politics, etc. I can see that having done damage to the TV viewership in the past decade.

But Europeans in general seem to be more mobile, have less stuff. So TV in the pocket. I can see it. I don't think that translate to USA/Canada/Mexico, Japan, Australia/NZ.

Quote:

These are very broad statements, but for the non-enthusiast or professional I wonder if we've crossed the line with this, and it's actually going to make less sense to worry about large screen quality in the next few years?
I don't think so, no. Attitude changes with age, especially regrets about doing something cheap and lazy. The young'uns may be fine with a crap conversion of grandma's wedding VHS tape, but we they get married, or want to show it to their kids, that's when the regret will seep in. But not everybody is like that, not now, even less in the future. You also have to think about things like documentaries, and filmmakers are forever having trouble getting good sources, or having to restore junk as best as possible. It's not pretty.

RobustReviews 05-19-2022 02:00 PM

Quote:

Originally Posted by lordsmurf (Post 84847)
Usually, yes. Some more than others. Most more than not. It takes multiple factors colliding just right to look still look analog.

Quote:

Alright kid.
That's a perfect and very common greeting from one individual to another in Manchester. I had to read that twice as it didn't fit in the context I read it. Other places may use "hello" or "hi". Manchester, "alright kid" is a perfect informal way to great a friend or acquaintance :D

"Alright our kid" may be reserved for a younger relation or close friend, there's a distinction!

dpalomaki 05-19-2022 02:25 PM

[soapbox] Quality conversion of VHS and other home formats are for those interested in history - in past events. And my observation is that it continues to diminish among the younger segments of the population. "Boomers' if you will were more interested in fine things, like china, crystal, silver flat ware, quality furniture, grandma's antique stuff, etc. The children of boomers have much less interest in it. And even less as you look at the even younger.

Example: 20 years ago a school group I support produced a video yearbook on VHS. About 70% of the members families paid $25 for a VHS tape shot of S-VHS/Hi8, edited to S-VHS and copied to VHS. In 2019 (the last pre-COVID year) maybe 50% picked-up their free DVD that was shot and edited in HD before conversion to DVD. Only a few wanted a free Blu-ray. This year it looks like a HD MP4 file download (shrunk to 3600 kbps) will be the favorite out pacing Blu-ray and DVD by a 2:1 margin.

The desire for high quality conversion is a niche market/demand these days. Few takes the time or energy required to appreciate quality stuff. The exception is large screens for sports and adult entertainment. People will say it looks nice, and then ignore what it takes to get there.

On audio, hearing loss among the old is a give, and among the young concert goers argues that ear buds and small screen players meet their quality needs. IMHO the participants here do not accurately reflect the viewers at large. [/soapbox]

lordsmurf 05-19-2022 02:50 PM

Quote:

Originally Posted by dpalomaki (Post 84849)
IMHO the participants here do not accurately reflect the viewers at large.

While not the "at large" masses, it's still a large segment of society that expects quality.

Why? Complaining is still a popular pastime, both legit and non-legit. On one end is the silly "VHS to HD" crowed that can never be pleased, due to obvious reasons (that they apparently cannot fathom more often than not). And on the other is the "why is it __" (insert actual error here). That bangs the drum to seek better -- as it should.

Ironically it's generally males that seek quality of video, and females are not interested, sometimes even trying to dissuade the male from partaking in the quality task. With other things, it's usually opposite, women nagging men for better. Why? Probably due to technical requirements. Stereotypes exists for a reason, and women dislike tech more than not. "Boy toys", as they often say. Obviously this isn't always accurate, nor necessarily even a majority. But certainly a plurality.

Interesting discussion in this thread. :)

dpalomaki 05-19-2022 03:06 PM

Quote:

While not the "at large" masses, it's still a large segment of society that expects quality.
Even if only 1% care about quality, 1% of the US population is well over 3 million people.

I've heard of women who want "Boy toys," not to be confused with "boy's toys." :woot:

It is the learning curve as much as any other barrier; both finding out there are better options, and then how to acquire and use them effectively. I may enjoy a good vocal, but I cannot carry a tune in a bucket (unless it is on tape/disc).

lordsmurf 05-19-2022 04:12 PM

Quote:

Originally Posted by dpalomaki (Post 84856)
not to be confused with "boy's toys." :woot:

:laugh:

Quote:

It is the learning curve as much as any other barrier; both finding out there are better options, and then how to acquire and use them effectively. I may enjoy a good vocal, but I cannot carry a tune in a bucket
Not even with a bucket here. It spills all over the floor, must clean it up with a mop. :oops:

latreche34 05-20-2022 12:19 AM

It must be something very different between the Britains and Americans, Colin a well known youtube member who does video capturing for a living in the UK did mention to me in several occasions that his customers prefer DV, Here in the US even if DV is the best they wouldn't know what to do with a 13GB an hour files anyway, so a re-encode to h.264 is a must which defeats the purpose of using DV in the first place.

mrwassen 05-20-2022 01:21 AM

Thanks for your feedback and other entertaining aspects of this thread :-)

Based on the feedback and more testing, the workflow is shaping up as follows:

JVC HR-S7860EK >
S-video / RCA audio >
ADVC-3000 >
SDI output via BNC cable >
Blackmagic DeckLink Mini Recorder 4K PCIe Card >
Lossless capture to .avi - software TBD (see below) >
Post capture editing = Vegas Pro v.16 >
Render mp4 / h264

So the open question is capture software, I have looked at/tried the following:

Virtualdub (tried both 32 and 64 bit)
=====================================
No matter how I configure this, the captured audio gets crackly and messed up - I must be doing something wrong as this software presumably is mainstream in the video capture community. (Any suggestions welcome)

Blackmagic Media Express
==================
Works ok but no timer (and I have some pretty bad footage where frames drop so I can't always turn on the "stop capture at frame drop" option). Also, when importing the AVI to Vegas Pro 16, no audio track shows up. I tried to research the missing codec without luck. Windows media player and other players recognize the audio. I am sure that this could be overcome with some intermediary remuxing using ffmpeg or similar, but I was hoping to minimize workflow steps where possible.

Amarec
======
Is probably fine, but I was hoping to avoid the $30 codec license fee :-)

OBS
===
While I realize that some have concerns about capturing with OBS, I was able to find out that OBS does support a lossless option: selecting Settings / Recording / Recording Quality = "Lossless Quality, Tremendously Large File Size" the capture produces an AVI file with the following codecs:

Stream 0
Codec: Ut Video (ULH0)
Type: Video
Video resolution: 720x576
Buffer dimensions: 720x576
Frame rate: 60
Decoded format: Planar 4:2:0 YUV
Orientation: Top left
Color space: ITU-R BT.709 Range

Stream 1
Codec: araw
Type: Audio
Channels: Stereo
Sample rate: 48000 Hz
Bits per sample: 16

This site lists lossless capture options: https://streamguides.gg/2021/06/how-to-capture-raw-or-lossless-video-in-obs-studio/

Does the above mentioned capability to capture lossless in OBS address the concerns raised by latreche and hodgey?

Thanks again for such a great forum.

Dennis

latreche34 05-20-2022 02:28 AM

In vdub you have to turn off audio monitoring, It's a well known issue of vdub that never got addressed. To monitor audio it is better to use an external monitor anyway, Does the ADVC-3000 have line out?
AmarecTV should be able to capture lossless without any codec needed.

lollo2 05-20-2022 04:11 AM

Quote:

Amarec
======
Is probably fine, but I was hoping to avoid the $30 codec license fee :-)
Use version 3.10, no AmarecTV own codec needed https://www.videohelp.com/software/AmaRecTV, then use the lossless codec you prefer

themaster1 05-20-2022 06:33 AM

Quote:

Originally Posted by mrwassen (Post 84865)
OBS
===
While I realize that some have concerns about capturing with OBS, I was able to find out that OBS does support a lossless option: selecting Settings / Recording / Recording Quality = "Lossless Quality, Tremendously Large File Size" the capture produces an AVI file with the following codecs:

Isn't OBS a screen recorder ? I wouldn't use that software but rather one that can tap directly from the card

lordsmurf 05-20-2022 06:43 AM

Quote:

Originally Posted by themaster1 (Post 84874)
Isn't OBS a screen recorder ? I wouldn't use that software but rather one that can tap directly from the card

Correct. OBS taps into the OS preview, or the graphics output screen -- not the direct driver for the card. It was designed as a streaming screen recording software, not capturing.

Screen (or preview) recording can have problems.

You could actually already do this with VirtualDub, and even with Windows XP, using Microsoft drivers. VirtualDub natively has the feature as well, screen recording, but it's rarely useful or mentioned. It never worked well, aside from a quasi AIW setup, since the AIW was actually piped through the graphics as well, so it worked fine.

Hushpower 05-20-2022 07:26 AM

2 Attachment(s)
Quote:

Isn't OBS a screen recorder ? I wouldn't use that software but rather one that can tap directly from the card
Quote:

Correct. OBS taps into the OS preview, or the graphics output screen -- not the direct driver for the card. It was designed as a streaming screen recording software, not capturing.
Why then does it show the attached capture cards to choose from for video capture? Given that every video editor under the sun can capture from the cards, why not OBS, when it clearly also has that feature/selection?

lordsmurf 05-20-2022 07:30 AM

I've not looked at OBS since last year, did something change? It does appear so. However, is it actually taking the card output, connecting to the driver, or just interfacing with the output preview?

And it now allows lossless recording?

mrwassen 05-20-2022 07:48 AM

Quote:

Isn't OBS a screen recorder ? I wouldn't use that software but rather one that can tap directly from the card
It has a capture mode similar to other capture utilities and supports the decklink card, I havent had any issues with it.

Quote:

In vdub you have to turn off audio monitoring, It's a well known issue of vdub that never got addressed.
I went through the vdub guide posted on this site in a fair amount of detail, but could not find anything about turning off monitoring. Could you please clarify how this is done?

The guide is here: http://www.digitalfaq.com/forum/video-capture/7427-capturing-virtualdub-settings.html

Quote:

To monitor audio it is better to use an external monitor anyway, Does the ADVC-3000 have line out?
Yes it has a set of red/white RCA monitor outputs.

mrwassen 05-20-2022 08:02 AM

1 Attachment(s)
Quote:

However, is it actually taking the card output, connecting to the driver, or just interfacing with the output preview?
Hmmm I wouldn't know how to determine this technically, all I can say is that it seems so.

Quote:

And it now allows lossless recording?
Yes, in Settings / Output / Recording / Recording Quality when "Lossless Quality" is selected the capture is written to a AVI file - see attached screenshot.

hodgey 05-20-2022 08:02 AM

OBS does capture from the same stuff as virtualdub can, though as it's designed around mixing stuff on a video surface rather than outputting the data from the card directly, you have to be very careful with the video settings to avoid it messing with the video.

Quote:

Originally Posted by mrwassen (Post 84865)
Stream 0
Codec: Ut Video (ULH0)
Type: Video
Video resolution: 720x576
Buffer dimensions: 720x576
Frame rate: 60
Decoded format: Planar 4:2:0 YUV
Orientation: Top left
Color space: ITU-R BT.709 Range

Those settings are not correct. Is it PAL or NTSC?
PAL should be 720x576 and 25fps,
NTSC should be 720x480 and 29.97... fps (NOT 30)
any other frame rate will result in dropped or inserted frames to compensate.
Color space should be ITU-R BT.601, not BT.709 (that is for HD video.).
Decoded format: Should be some variant of 4:2:2 YUV, not 4:2:0 (which will mess with the color since the video is interlaced)
Important that these things are correct both in OBS settings and for the video codec used, it's not guaranteed to match.

lollo2 05-20-2022 08:07 AM

Quote:

OBS does capture from the same stuff as virtualdub can, though as it's designed around mixing stuff on a video surface rather than outputting the data from the card directly, you have to be very careful with the video settings to avoid it messing with the video.
And this is why!

lordsmurf 05-20-2022 08:10 AM

Quote:

Originally Posted by hodgey (Post 84882)
OBS does capture from the same stuff as virtualdub can, though as it's designed around mixing stuff on a video surface rather than outputting the data from the card directly, you have to be very careful with the video settings to avoid it messing with the video.

An easy tell is always digital-only artifacts, such as screen tearing.

I get rather tired of hearing comments like "it seemed fine to me", but it wasn't picked over in detail, to actually see if there are intermittent errors. Too many people act as if certain errors will be immediately observable, and jump out of the screen and slap them in the face. Errors can be random, and pernicious. You'll only see them when you see them. And it's often long after the capture was done, sometimes years later. (A lot of people capture 100 family videos, and don't even watch 1 of them until all 100 are done. Bad form, sloppy science.) After you notice, especially if it's cyclical, you'll be annoyed by it. This is why so many people are recapturing video. The 2000s was failed first attempt, 2010s/2020s is 2nd try. Happens all the time. Those base-on-nothing "fine" comments mislead newbies far too often, usually a case of newbies misleading newbies (blind leading blind).

mrwassen 05-20-2022 10:11 AM

Quote:

I get rather tired of hearing comments like "it seemed fine to me", but it wasn't picked over in detail, to actually see if there are intermittent errors. Too many people act as if certain errors will be immediately observable
Yes, I do admit to be a clueless soul trying to figure this stuff out, however

Quote:

"it seemed fine to me"
means that as clueless as I am, I actually viewed the captured footage carefully but saw no signs of anomalies (however I have no other way of checking than visual review).

BTW, could somebody please help with this question?

Quote:

Quote:
In vdub you have to turn off audio monitoring, It's a well known issue of vdub that never got addressed.

I went through the vdub guide posted on this site in a fair amount of detail, but could not find anything about turning off monitoring. Could you please clarify how this is done?

latreche34 05-20-2022 10:31 AM

Go to audio tab, uncheck audio playback.

mrwassen 05-20-2022 12:58 PM

1 Attachment(s)
Quote:

Go to audio tab, uncheck audio playback.
Sorry to persist on this, but I did already have that unchecked. I have attached a file showing screenshots of all audio related settings.

Any other ideas? (I can post a very short sample of avi is that helps)

latreche34 05-21-2022 12:36 AM

vdub may not work properly with a pro capture device, I personally never got vdub to capture properly but MediaExpress works flawlessly, We are talking 270Mb/s in 10bit, 8bit slightly lower, but still a more lean app like MediaExpress or AmarecTV is the way to go, vdub is filled with plugins, filters, options and settings and even with audio monitoring turned off it could choke on 270Mb/s.

mrwassen 05-21-2022 01:17 AM

Thanks for your reply.

After playing around with vdub and AmarecTV I decided to stick with MediaExpress. The only remaining issue I had was that when I imported the resulting lossless AVI file into Vegas Pro, it would not recognize the audio track. To get around this I came up with the following ffmpeg conversion syntax based on googling/reading of the ffmpeg documentation:

ffmpeg -i input.avi -acodec pcm_s16le -vcodec copy output.avi

This will essentially copy the lossless video without modification and convert the audio to a standard that Vegas Pro will recognize.

I thus end up with a lossless AVI file (PAL) which exactly matches hodgey's specs:

720x576
25fps,
Decoded format: 4:2:2 YUV

So I think I am good to go.

I thank everyone on this forum for their input in the process and their patience with my beginner questions - it has been a steep but rewarding learning curve.

Dennis

RobustReviews 05-21-2022 05:28 AM

Quote:

Originally Posted by hodgey (Post 84882)
OBS does capture from the same stuff as virtualdub can, though as it's designed around mixing stuff on a video surface rather than outputting the data from the card directly, you have to be very careful with the video settings to avoid it messing with the video.

Yes, I've raised this few times too when LS and others repeat that it's only screen capturing software. I don't especially like OBS, but it does direct capture from hardware, I've even linked the source code showing this. OBS has been able to do this for a very long time.

Personally, I don't use it, I don't like it for video capture, but it can make a perfectly good job of it if you dial in the right settings. It's certainly not its forté, but it's demonstrably incorrect to just say it's only capable of screen recording.

If individuals like it and get the results they like, then crack on in my opinion.

There are a lot of purity tests set by some individuals in this community. It's quite amusing to watch sometimes.

themaster1 05-21-2022 06:57 AM

I'm tryin' OBS right now, seems like it can "tap" into the ouput of my hdmi card. The encoding options are limited though (NVenc or x264), and aac 320 for audio, not quite enough. No deinterlacing filter that i can see aswell or infos on dropped frames. I don't think it's adapted for our purpose

RobustReviews 05-21-2022 07:12 AM

Quote:

Originally Posted by themaster1 (Post 84900)
I'm tryin' OBS right now, seem like it can tap into the ouput of my hdmi card. The encoding options are limited though (NVenc or x264), and aac 320 for audio, not quite enough

I can't speak as to compatability with your card.

From an audio perspective 320 AAC is complete overkill for any domestic videotape though, don't be put off at that, you can comfortably capture all information at far lower rates than that. 320 is usually reserved for other purposes, AAC 128 will comfortably digitise VHS audio.

lordsmurf 05-21-2022 10:08 AM

128 AAC is too low for this purpose.

Let's go back to AC3 for a moment.
- 192 was the minimum, noticeably compressed (unless your speakers and hearing was lousy).
- 224 was the standard low for high quality source, no noises, mild compression detected in some sources.
- 256 was the standard high for most decent or quality audio, no noticeable compression
- 384 was required for audio with noises, such as hiss, ie most consumer analog videotapes, even with audio NR/restore/processing.

Those are stereo values. 6-channel doesn't equate, due to more channel, but also less actual audio in the channel. But still, baseline for 6-channel was 384, up to 512.

Now comes AAC.

It essentially moved the numbers down by 2 spots.

So, in AAC:
- 96 is the low minimum, noticeably compressed (unless your speakers and hearing is lousy)
- 128 was the high minimum, less noticeable, but still noticeable at times
- 160 was the standard low for high quality, some sources can cause oddities and loss
- 192 is the standard high for high quality -- or low for low quality, with oddities/loss
- 224 or even 256 is usually needed to properly process noisy audio from video tapes, mostly so you can distinguish the audio noise from the audio high.

With AAC, NR/restore is suggested to remove the noise as much as possible, but it still cannot be 100% filters out, and you don't want noise to blend with the highs.

The compression issue with AAC is not the same as AC3. With AC3, there was the traditional "digital sound" to the audio, as values reduced. But AAC is more like H.264. PEG-2 gave you blocks and mosquito noise, while H.264 just blurs and mushes. AAC with a low bitrate starts to mush the audio, and it can gets harder and harder to distinguish sounds. If you have XM radio, the worst MLB off-game audio is a good example of this. (Note that the MLB is really low bitrate stream, so it's far below what you'd get from AAC 128.) So 128 doesn't "sound digital", but it definitely mushes frequencies together.

AAC is far more complex than AC3, because it has multiple profiles, and actually is not constrained to bitrates like 128, but could be 125, 130, 132, etc. But that's another issues as well, in the decoder expectations.

Using Fraunhofer is probably one of the most important aspects.

I could go on, but out of time.

FYI, this isn't my opinion. This is the sort of collected data that I had access to when I worked for studios. But some of this is so commonly known that "the scene" also uses this in widely accepted audio specs by contributing members.

NOTE: You should not be capturing audio directly to AAC.

latreche34 05-21-2022 04:41 PM

Quote:

Originally Posted by mrwassen (Post 84896)
The only remaining issue I had was that when I imported the resulting lossless AVI file into Vegas Pro, it would not recognize the audio track. To get around this I came up with the following ffmpeg conversion syntax based on googling/reading of the ffmpeg documentation:

ffmpeg -i input.avi -acodec pcm_s16le -vcodec copy output.avi

This will essentially copy the lossless video without modification and convert the audio to a standard that Vegas Pro will recognize.

What audio MediaExpress spits out? Mine outputs PCM 48Khz 24Bit, If this is indeed your output I don't see why Vegas would not recognize it.

On a side note, If you already know how to use script commends why don't you just use ffmpeg and QTGMC to do pretty much anything needs to be done post capture? NLE is a pain in the a$$.

mrwassen 05-22-2022 01:54 AM

1 Attachment(s)
Quote:

What audio MediaExpress spits out? Mine outputs PCM 48Khz 24Bit, If this is indeed your output I don't see why Vegas would not recognize it.
Mine spits out the same audio = PCM 48Khz 24Bit, however as mentioned when added to the Vegas Pro timeline, only the video track shows up. After converting the audio to something like PCM 48Khz 16Bit, the audio track also appears - not sure why, maybe a missing codec on my PC?.

Quote:

On a side note, If you already know how to use script commends why don't you just use ffmpeg and QTGMC to do pretty much anything needs to be done post capture? NLE is a pain in the a$$.
Agree that it can be a bit painful, my use is very limited, and if not needed I will just use ffmpeg. Here are a couple of situations where it comes in handy:

1) Really bad video footage with noisy transitions and dropped frames (where the capture stops). This ends up creating a number of AVI files. I put these on the timeline, trim off the noise and render as a single mp4.

2) Precious but real crappy footage recorded on cameras which are faulty, e.g. missing a color, I can sometimes improve on these using some of the FX filters, Neat video etc. (although the basic tenet of my coversion is to intervene as little as possible with effects/editing /filtering etc.)

-- merged --

In the interest of "vindicating" OBS's reputation as a "screen recorder only", I spent some time time trying to replicate the lossless capture achieved using the Blackmagic Media Express software (v. 3.8) using OBS Studio (v.27.2.4).

OBS has an advanced output option which allows for specifying custom ffmpeg style arguments which provide much more control over the capture parameters than the standard options. I believe the results came quite close - I have documented the comparison results in the attached PDF in detail.

I am not saying it is recommended to use OBS over Media Express - it is quite true as pointed out by several forum members that OBS has many more options/moving parts and it would be quite easy to mess up the transfer if any of the key option selections are incorrect. Media Express on the other hand has very limited options, and thus less room for error.

But I thought it would be an interesting exercise nonetheless.

A synchronized side-by-side full viewing of both clips using Kinovea did not reveal any obvious visual differences, but then again it is early days for me and I might have missed something a trained eye would detect.

I would be interested in hearing opinions on whether the resulting video characteristics are comparable, and/or any thoughts on how they might differ significantly - in short would OBS configured in this manner be an acceptable replacement?

latreche34 05-22-2022 03:08 AM

When you capture multiple segments with MediaExpress the easiest, quickest and most lossless way to trim them or merge them is vdub2, You don't even have to select the files one by one, MExp names files in incremental numbers, So you only need to load the first file to vdub2 and then go to file/append video segment and vdub load all the files in the same file name matrix. They will all be loaded in the timeline as one large file and from there do your editing and output the file without transcoding, You can also output to HuffYUV for almost third the size with lossless compression. You just have to make a folder for each tape or capture to avoid automatically loading files from previous captures.


All times are GMT -5. The time now is 03:32 AM

Site design, images and content © 2002-2022 The Digital FAQ, www.digitalFAQ.com
Forum Software by vBulletin · Copyright © 2022 Jelsoft Enterprises Ltd.