Record VHS-video using an O2?

trycoon

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Aug 30, 2021
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Hi, I just inherited a bunch of old VHS-tapes and looking for a way to digitalize them for the future to come. Instead of buying a USB gadget for my PC I was hoping to be able to use my 300MHz R12000 O2 with Media module to do this. But I need some hands-on suggestions on how to do this best. If I only could capture the video in PAL (720x568) in a MPEG2-format (?), then I could transfer it to my PC for postprocessing and H264 encoding and so forth.

What software should I use on my O2 and what settings? I have Adobe Premiere on the O2, would it do? What CODEC should I use to make use of the hardware MPEG-encoder in the Media module?
 

Jan

Member
May 26, 2022
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If you only want to save these old tapes to the digital domain, I suggest the use of a (good) USB video digitizer to do the job.

But just for fun, I did it with a test video last year - just to see, what the old lady could do.
I used Adobe Premieres capturing function for the job. It suited me better than the capture function from IRIX.
I think, I used only RAW video but I’m not quite sure about that.
After the capturing was done, I transferred the video to my DiskStation via NFS and tried to play it on Windows with MPC-BE, which worked well. It was even recognized as SGI video stream :).
The quality was as bad as expected with VHS, so don’t put your hopes too high…
 
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trycoon

New member
Aug 30, 2021
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If you only want to save these old tapes to the digital domain, I suggest the use of a (good) USB video digitizer to do the job.

But just for fun, I did it with a test video last year - just to see, what the old lady could do.
I used Adobe Premieres capturing function for the job. It suited me better than the capture function from IRIX.
I think, I used only RAW video but I’m not quite sure about that.
After the capturing was done, I transferred the video to my DiskStation via NFS and tried to play it on Windows with MPC-BE, which worked well. It was even recognized as SGI video stream :).
The quality was as bad as expected with VHS, so don’t put your hopes too high…
Yes, I guess I could buy one of those video digitizers, but I tought that a old-tech O2 would be good enough for a old-tech VHS. A VHS-tape has low resolution and crappy quality(!!!) with todays standards, can a modern digitizer realy make any difference? I mean it can't provide more pixels than there where in the original, unless added with interpolation or fancy AI. But you suggest using a RAW SGI-format intead of Indeo-video, Quicktime, MJPEG (and the other ones I can't remember)? An hour of uncompressed video will take some time to transfer over a 100Mbps network, and can the harddisks handle the bandwidths required for capturing in RAW-format unless using RAID-0? I tought the hardware supported CODECs in the O2 could help with this, to cut down the bitrate to the disks, then I can re-encode on my PC to get a more modern and compact format.

More suggestions are more than weilcome! :)

// Henrik
 

Jan

Member
May 26, 2022
47
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Germany
I’m not quite sure. It’s just a guess. But it’s obviously more convenient to use modern stuff.
And regarding the format: as I wrote, I’m not quite sure, what I chose that day. It could have been M-JPEG :unsure: , so the VICE ASIC had something to do…
I did capture a music video with only a few minutes duration. The file had a few hundred MB, I think.
Just do some tests on your own with the different codecs.
 

trycoon

New member
Aug 30, 2021
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Sweden
After testing Media recorder I can say that recording PAL (720x576) is not possible with my O2, the CPU is at a constants 90%, frame drops are substantional. Capturing at 352x288 works great, but quality is much poorer.
I read something interesting, "mediarecorder doesn't use dmrecord" (http://www.sgidepot.co.uk/ice.html), I don't know if that translates to that Media recorder does not use the ICE-acceleration or just that it does'nt use the dmrecord commandline program?

Next up I'm going to test recording from CLI instead of the Media recorder or Adobe Premiere GUI:
Code:
dmrecord -p video,device=mvp,comp=jpeg,engine=ice,brate=30000000 -p audio,channels=2 video.mv
Useful links:
 

mapesdhs

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Jul 23, 2020
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Edinburgh, Scotland, UK.
www.sgidepot.co.uk
trycoon wrote:
> After testing Media recorder I can say that recording PAL (720x576) is not possible with my O2, ...

It can, but you need to use the right settings: QT, 2-field SGI JPEG, constant bitrate (disk based 3MB/sec).

However, MR is flakey. It works better with dmrecord.


> recorder does not use the ICE-acceleration or just that it does'nt use the dmrecord commandline program?

The latter; it does use ICE but it's not simply calling dmrecord. There's a weird mix of relationships between the various libs, command line tools and GUI tools, especially how MovieMaker works.

I have done successful capture with MediaRecorder, including from VHS (TBC helps or something to clean up the signal), but something about how its interface works makes the process of choosing the settings a bit klunky. It probably works better with Premiere, though I've never tried it. Or one could use Avid perhaps; I did this long ago but I think it was with AV2. It worked ok with no frame drop, but the general responsiveness was much better with an Octane (I was comparing an R12K/400 O2 AV2 to an R12K/400 Octane MXE DIGVID).

Recently I did some experiments with MovieMaker/Premiere and DV format files; O2 fared rather well compared to other SGIs, especially for playback, though of course Octane, Fuel, etc. have an edge for file loading. However, export times are a much larger proportion of a typical job, so O2 wins overall despite slower loading times, and it's the only SGI that offers solid real-time playback (or there's Cosmo of course for Indy, Indigo2 and MGRAS Octane, but that's less flexible and expensive, though Cosmo is supremely reliable with dmrecord). Other systems must use different libs though (which on non-O2 systems seem to chew a lot of RAM with MovieMaker, while also exhibiting some curious errors sometimes), and I suspect (at least for DV) the libs on O2 used by MovieMaker are not the same libs used by Premiere. Am working on a longer writeup atm to add to my site.

Using an O2 for capture is certainly fun, but I do have a USB dongle I use aswell which works very nicely, or sometimes a Cosmo2 I2 which copes with noisy signals very well. Funny thing though, the simple editing tool supplied with the USB dongle looks and is used in a remarkably similar manner to MovieMaker, and is thus very intuitive.

I do of course use a PC for final format conversion to h264/h265 (NVEnc with a 1080 Ti, which can smash through SD material so long as one has a decent enough CPU to feed it, more cores being relevant; I use a 5700X).

Ian.
 
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