Add GIF ripping guide

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+rss = "How to make GIF files from videos"
+date = Date(2023, 03, 16)
+tags = ["fun", "recipe"]
++++
+
+# Artisanal GIF Ripping
+
+!!! note "Pronounciation"
+
+    /dʒɪf/ is the format, /ɡɪf/ is the handball club in Eskilstuna, Sweden.
+
+GIF, *the* graphics interchange format, is probably the most [inefficient]
+representation for animated images in quality/size that is widespread today.
+However, it does live up to its name, being also the most portable format
+for animated graphics exchange.  If a device has a color display
+and is connected to the Internet, tis likely to support GIF out of the box.
+
+Like with incandescent light bulbs, it'd be wasteful to have not switched
+to more efficient alternatives, though GIF still has its charms.  Not having
+to worry about codec compatibility is one thing, the nostalgia induced
+by the `.gif` file extension is another.  For years, I got an *Internet* folder
+full of those (along with still images and short videos) for offline viewing,
+shitposting and reaction.
+
+More recently, I [began][hyper] [to][milos] [make][grenade]
+[my][tron] [own][potato] [animated][xô] [images][nf]
+and take pride in them.  This tutorial will step-by-step
+lay out my process in cutting out a high-quality GIF
+from a video, so [you can be just like me][role model]!
+
+\toc
+
+## Decide on the Format
+
+> Just because you can doesn't mean that you should.
+
+Good things often don't come out of desire, but necessity.
+GIF is cool because tis portable, but plain text is even more portable.
+Multimedia weigh hundreds of kilobytes each, so they better best convey
+whatever information they're meant to communicate.  Don't replace
+the audio with a subtitle just so it can be an animated image.
+Don't loop anything longer than a few seconds.
+
+There is an old saying: if tis doing fine being a video, let it be a video!
+Videos don't need each frame to be perfect, and thus all the following steps
+can be done in a single ffmpeg command.  Work smart, even just for shitposting.
+
+## Extract Frames
+
+Open the source video in [mpv], seek then spam `.s` repeatedly.
+That's all, y waste time write lot word wen few word do trick?
+
+Aight, maybe there's a bit more to it.  Operating on the level of frames
+will allow you to skip redundant ones in case of misencoded sources
+or duplicate and reverse a subsequence for a closer-to-perfect loop,
+but really, there's not much to talk about.
+
+## Crop and Resize
+
+Ripping a GIF from a video is taking a sequence of frames out of context.
+Framing and some objects in the scene might not make sense in the target
+animated image.  Some also like to export videos with giant black bars
+just to fuck with us.  That's where cropping comes into play.  For measuring
+I use [GIMP], which doesn't seem to be the right tool for the job,
+so please let me know of anything lighter that has a ruler.
+
+In addition, videos from social media (and space-efficient movies)
+are heavily compressed and look pretty bad for their resolution.  Usually
+I have to shrink them down to two third or a half of their original width
+for them to look decently sharp.  When you have the geometry in mind,
+fire up [ImageMagick]:
+
+```sh
+crop="-crop ${w}x${h}+${dx}+${dy}"
+resize="-resize ${width}x${height}"
+parallel -i sh -c "convert $crop $resize"\
+' {} $(basename {} .jpg).png' -- mpv-shot*.jpg
+```
+
+In case you don't have [moreutils]/[GNU parallel],
+or if you are rocking a single-CPU machine, run:
+
+```sh
+mogrify $crop $resize -format png mpv-shot*.jpg
+```
+
+For resizing, image processing expert Nicolas Robidoux wrote
+a long article on [resampling filters].  Although I can't spot
+any distinction for this use case, it doesn't hurt to give it a read
+and play around with different options.
+
+![Pam stating that they are the same picture](/assets/same-picture.png)
+
+## Combine
+
+We are going to encode in best quality possible using [gifski].
+The reason we converted from JPEG to PNG earlier is that our precious encoder
+refuses to touch any other *image* format, and that mpv take screenshots
+in JPEG by default (you can [configure][mpv screenshot] it to write in
+lossless format but in my experience, the source videos are often too heavily
+compressed for it to make any difference).  Anyhow, invoking gifski
+is rather straightforward:
+
+```sh
+gifski -r $fps -Q 100 -o $name.gif mpv-shot*.png
+```
+
+Note that it optionally takes width and height as an argument
+and yield better quality than with pre-shrunken images,
+but at the cost of a significantly larger file size.  Choose wisely.
+
+[inefficient]: https://telegram.org/blog/gif-revolution
+[hyper]: https://nixnet.social/notice/A8VniqEBKfJvMc2dTE
+[milos]: https://nixnet.social/notice/A9gMc47yxgoTNDIa7U
+[grenade]: https://fe.disroot.org/notice/ANK2GqGxIdcDGBRAFU
+[tron]: https://nixnet.social/notice/AOhGjOUwKJmiEFNLkG
+[potato]: https://fe.disroot.org/notice/APhUh2H8radlKKIZGa
+[xô]: https://fe.disroot.org/notice/APhUh2H8radlKKIZGa
+[nf]: https://larkspur.one/notice/ATe4i9UvhxjiFvXprs
+[role model]: https://www.youtube.com/watch?v=TVMK2gQig4A
+[mpv]: https://mpv.io
+[GIMP]: https://www.gimp.org
+[ImageMagick]: https://imagemagick.org
+[moreutils]: https://joeyh.name/code/moreutils
+[GNU parallel]: https://www.gnu.org/software/parallel
+[resampling filters]: https://imagemagick.org/Usage/filter/nicolas
+[gifski]: https://gif.ski
+[mpv screenshot]: https://mpv.io/manual/master/#screenshot