[FFmpeg-user] Benefits from Chroma Upsampling v4l2 8bit 422 to 10bit 422 FFV1 backup?

[Terje J. Hanssen]

Den 22.05.2025 08:53, skrev Carl Zwanzig:
> On 5/20/2025 4:15 PM, Terje J. Hanssen wrote:
>> And yes, I agree. I didn't tell that I actually have a legacy pretty 
>> good TBC (built in a Videonics MX-1 videomixer)
>
> That's really a consumer product, not a professional one (and not 
> broadcast quality). If you can get your hands on one, look for 
> DPS/For-A/Sony/Tektronix. Or use a scan converter like a Folsom 
> ImagePro, that'll do the TBC job along with the A/D and has enough 
> adjustments.
>
> That aside, if you're after "good enough", that's fine; but please 
> don't equate that to "best quality". (I will acknowledge that S-VHS 
> is/was not a high-quality media to start, so there's definitely a 
> point of diminishing returns here.)

OK, neither professional video media  nor equipments; rather I am after 
"best practical and possible" backup quality out of my available 
footages and equipments/devices.

My 15 years or 150 hours+ analogue video footages were recorded since 
1992 using Sony TR-805/-808/-2000 Hi8 camcorders and Panasonic FS-200 
SVHS VCR (and later on additional 10 years digital HDV since 2007). So I 
am also curious to recover how well or bad the analog recordings have 
preserved on tapes during these 30 years +/-.

Well, MX-1 made for composite and S-video, was targeted at video (hobby) 
enthusiasts. TBC and "Broadcast quality" are referred from the MX-1 
specifications (manual and Video primer):

    VIDEO PERFORMANCE
    Meets FCC broadcast specifications.
    Digital conversion: 13.5 MHz, 4:2:2, 8-bit
    quantization, 4 X subcarrier oversampling.
    Dual-field infinite-window time base corrector.
    Time base meets RS-170A standard.
    Compatible with all NTSC videos sources and
    tape formats. (PAL version available.)
    Gain: Unity.
    S/N Ratio: 56 dB
    Resolution: 5.0 MHz

    "Many consumer-level digital products work at lower sampling rates,
    with fewer bits per pixel  and a 4:1:1 ratio, reducing the amount of
    information captured. The NTSC's version of the MX-1 delivers a
    broadcast quality picture with 14.318 MHz, 8-bit 4:2:2 sampling. The
    PAL version of the product uses 17,72 MHz sampling."

While my refurbished Hi8 and S-VHS VCRs (Sony EV-S880E and Panasonic 
NV-HS1000EG) have a "line based TBC", in my experience only the MX-1 TBC 
effectively managed to correct especially jump, waver or flagging 
problems from a slippery Hi8 tape type recorded with the early Sony 
TR-805/808 camcorder's tape drive train.


But to keep on the initial target and question;

No one  has so far commented on the results described in the referred 
article 8bit 422 to 10bit 422 upsampling with temporal noise filtering. 
While the mentioned Net Video filter doesn't look to be available for 
FFmpeg, maybe nlmeans or HQDN3D could make similar effects?
https://www.eoshd.com/comments/topic/26710-8bit-%E2%86%92-10bit-video-with-temporal-noise-filtering-stunning-results/


Terje J. H