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+# Reading old videos (vhs/hi8...)
+
+https://gleitz.info/forum/index.php?thread/47572-tutorial-hochwertiges-digitalisieren-von-analogen-vhs-videokassetten-und-andere/
+
+1. player (ideally original device used to create the hi8 cassette)
+2. s-video to scart adapter
+3. panasonic dvd/bluray player with hdmi out (ideally set to 480i/576i)
+4. hdmi splitter to remove protection
+5. capture card
+
+Lossless recording with virtualdub (version!)
+
+filter with vapoursynth (qtgmc [lower sharpening!], dering, dehalo)
+export to prores with ffmpeg (high quality, can be read by resolve even on linux)
+auto cut with davinci resolve
+export to DNxHR (similar to prores)
+compress and cut first frame with ffmpeg (x264/x265/av1, aac/opus)
+
+
+Encode:
+# -aspect is DAR 
+# PAR = DAR/SAR
+# PAR 4:3-PAL (ITU): 1150/1053
+# 1150/1053=x/(720/560)
+# x = 1150/819
+ffmpeg -ss 0.02 -i "2023-04-30_05-part2_00021612.mov" -aspect 1150:819 -pix_fmt yuv420p10le -c:v libsvtav1 -crf 24 -preset 5 -svtav1-params tune=0:film-grain=12 -c:a libopus -b:a 128k "2023-04-30_05-part2_00021612.mkv" -n
+
+
+---
+
+## Aspect ratios
+
+Original 720×576     5×4
+Should be stretched to 4×3
+
+Cropped and stretched appropriately (through the aspect ratio flag) the content ends up being approximately 7×5
+
+---
+
+
+I
+want to preserve data
+as it has fallen out of fashion, it's getting harder to properly watch old analog video and to properly view old analog photo slides.
+analog data degrades, so it should be digitized sooner than later, before the quality worsens noticeably.
+
+
+## hi8 (also applies to VHS etc.)
+dad used an old camcorder (TODO: branding?) manufactured by Sony, I believe.
+A lot of my childhood is recorded on it. Luckily we still have the camcorder it was recorded with, as well as a Panasonic Blu-Ray recorder for handling the conversion.
+hi8 is higher quality than VHS 
+
+### The digitization process
+
+### recording
+Blu-Ray recorder can't output interlaced at 576p
+bought damaged Panasonic DVD recorder off ebay
+ DVD drive was apperantly not working, but it fixed it self without me doint anything.
+ Front panel had bad contact, so the display and the IR Remote sometimes didn't work, but taking it apart and reassembling it fixed it.
+
+### filtering
+Filtering in vapoursynth (learned from the anime scene)
+
+Crop
+EdgeChromaFix(InputType=1, Sharpness=0.2) (to smooth and denoise it)
+qtgmc (don't overdo it)
+HQDeringmod
+FineDehalo
+
+TODO: vs script
+
+
+I use Fedora Linux, so I used [yuuno](https://yuuno.encode.moe/) in an archlinux docker container (→ github.com/nalsai/vapoursynth-yuuno-docker) for editing and testing my script. (This tag works nicely: https://github.com/nalsai/vapoursynth-yuuno-docker/pkgs/container/vapoursynth-yuuno/88321925?tag=sha-ecb25f9)
+And then ran it on all files via bash
+
+TODO: script
+
+
+### cutting
+
+- cutting clips
+Davinci Resolv auto scene detection
+two more issues:
+color is a bit rainbowy at the beginning (already present in source) 
+audio start and end are slightly delayed
+fixed both by cutting of the first 10 frames in the final encode with ffmpeg → see encoding
+
+### encoding
+
+encode
+TODO: full ffmpeg command
+gets quite small 2 to 3 Mbit/s
+
+### Problems
+- start and end of tapes have artifacts due to tension
+--> sometimes recorded those multiple times
+beginning always has one frame that is shifted downwards - not the same frame each time -> can be corrected by making multiple recordings and replacing the shifted frame with the same frame from another clip. (I did that once, but it's too much work to do it for every tape or to write a vapoursynth script to detect and fix it)
+- edges
+cropping (I actually cropped a couple more pixels on both sides but it looks perfectly clean now)
+- chroma on right edge 
+wrote custom script to extend the chroma
+TODO: vs script
+- Aspect ratio
+PAR (I give it to ffmpeg in the final encode)
+Could also interpolate for example high quality nnedi3 in vapoursynth
+TODO: ffmpeg parameter
+
+
+## Conclusion
+
+Actually pretty high quality
+method is cheap and better than transferring to DVD or grabbing directly with a cheap analog capture device. Panasonic conforms to norms capturing this way has no compression artifacts at all (until I convert it to prores for resolve) and even if you capture with lossy compression there much fewer artifacts than with other methods.  The hardest part is getting 
+Luckily the tapes were all still in great condition but as it's an analog format you always have to live with a couple of artifacts.