Den 22.05.2025 05:37, skrev Andrew Randrianasulu:
you
пн, 19 мая 2025 г., 15:55 Terje J. Hanssen <terjejhans...@gmail.com>:
My first backup generation of my PAL Analog S-video footages on tapes
was digitized to SD 576i50 DV25 with 8-bit 4:2:0 color depth and
25 Mb/s
video bit rate.
IMO playback from DV25 backup files visually lack some brightness and
colors compared with native playback from S-video tapes.
Now I am testing another backup method with purpose of best practical
video quality using ffmpeg to encode lossless compressed FFV1.mkv
files:
Analog video camera/player --> S-video/HDMI converter -->
HDMI/USB3
capture card --> v4l2 --> ffmpeg/ FFV1.mkv
10-Bit 4:2:2 Video is recommended for Analog Tape Transfer due to
color
shades and branding
https://www.archivalworks.com/blog/10-bit-video-transfer
Well, my ms2130 HDMI/USB3 video capture card
while looking around for "something else" I noted this thread talks
about patching firmware on ms2130 device to disable sharpening and get
unclipped (full range) YUV values.
Not that it should matter for cassette video source, but for VGA
capture it apparently mattered:
https://68kmla.org/bb/index.php?threads/decent-video-capture-for-30.49954/
If anyone want to test this route do not forgot to back up original
firmware first!
Thank you for the tip, which I have noticed for a possible attempt,
later on.
I looked at the two (TV) test pictures, before and after fw patching,
but I couldn't discover any visual differences(?)
https://github.com/steve-m/ms2130_patcher?tab=readme-ov-file#macrosiliconultrasemi-ms2130-firmware-patcher
"patching firmware on ms2130 device to disable sharpening and get
unclipped (full range) YUV values."
Not sure what this really mean, but I expect this will still be 8-bit
color depth(?)
IMO it is safest to follow the idiom "if it ain't broke, don't fix it".
https://www.cnx-software.com/2022/11/07/ms2130-based-4k-hdmi-to-usb-3-0-video-capture-dongle-sells-for-19/
ffmpeg -hide_banner -f v4l2 (from case 1)
Input
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
Output
Stream #0:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p(tv, progressive)
That is, I will keep 8-bit 422 through the whole workflow, via first TBC
rectification (MX-1).
The A/D converter is probably specified using maximum 10-bit 1.62 MSPS
sampling.
My purpose and device environment as a reference, was mostly discussed
in a topic back in 2023:
[FFmpeg-user] Capture HDV and S-Video from tape via HDMI-USB to 422 FFV1
https://www.mail-archive.com/ffmpeg-user@ffmpeg.org/msg33225.html
The real new topic meant this time, was my curiosity when I discovered
this post on reddit
Upsampling by Denoising 8-bit footage into 10-bit? : r/colorists
https://www.reddit.com/r/colorists/comments/fo5oez/denoising_8bit_footage_into_10bit/
Terje J. H
achieves YUYV2 or 8-bit
4:2:2, which is not 10-bit but yet twice as much color info compared
with DV25 4:2:0.
Q1
Therefore my question here if it yet may be
Benefits from Chroma "Upsampling" v4l2 8bit 422 to 10bit 422
FFV1
backup?
While some say this is fake upsampling like filling 8-bit data in a
10-bit container, other say this may be beneficial with temporal
noise
filtering
https://www.eoshd.com/comments/topic/26710-8bit-%E2%86%92-10bit-video-with-temporal-noise-filtering-stunning-results/
Q2
So let me hear if this may be applied with some ffmpeg denoising
filters
like time base correcting, tape grain or snow?
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