commit 5b4f601fc74a1ed607fb93fea7cabc4cc3a1f5ba
parent 3579773d924c2866f6a1663fc34c4d3694ac1df2
Author: Sebastiano Tronto <sebastiano@tronto.net>
Date: Mon, 6 Mar 2023 22:24:32 +0100
Resized images + blog post
Diffstat:
14 files changed, 94 insertions(+), 0 deletions(-)
diff --git a/src/blog/2022-09-10-netbooks/darkstar.jpg b/src/blog/2022-09-10-netbooks/darkstar.jpg
Binary files differ.
diff --git a/src/blog/2022-09-10-netbooks/final.jpg b/src/blog/2022-09-10-netbooks/final.jpg
Binary files differ.
diff --git a/src/blog/2022-09-10-netbooks/hd.jpg b/src/blog/2022-09-10-netbooks/hd.jpg
Binary files differ.
diff --git a/src/blog/2022-09-10-netbooks/scramble.jpg b/src/blog/2022-09-10-netbooks/scramble.jpg
Binary files differ.
diff --git a/src/blog/2022-12-30-blog-ready/pc-planner.jpg b/src/blog/2022-12-30-blog-ready/pc-planner.jpg
Binary files differ.
diff --git a/src/blog/2023-01-28-windows-desktop/settings.png b/src/blog/2023-01-28-windows-desktop/settings.png
Binary files differ.
diff --git a/src/blog/2023-01-28-windows-desktop/tiling.png b/src/blog/2023-01-28-windows-desktop/tiling.png
Binary files differ.
diff --git a/src/blog/2023-02-25-job-control/jobs-diagram.png b/src/blog/2023-02-25-job-control/jobs-diagram.png
Binary files differ.
diff --git a/src/blog/2023-03-06-resize-pictures/resize-pictures.md b/src/blog/2023-03-06-resize-pictures/resize-pictures.md
@@ -0,0 +1,86 @@
+# Resizing my website's pictures with ImageMagick and find(1)
+
+I have noticed that most of the pictures I have uploaded on this website
+are incredibly large:
+
+```
+$ du -h -d 1 sebastiano.tronto.net
+42M sebastiano.tronto.net/gemini
+42M sebastiano.tronto.net/http
+42M sebastiano.tronto.net/src
+100M sebastiano.tronto.net/.git
+225M sebastiano.tronto.net
+```
+
+Stupid modern phones and their multi-megapixel cameras!
+I definitely do not want my minimalist blog to waste your bandwidth,
+I have to fix this. I could just go through all my pictures and resize
+them with something like [gimp](https://www.gimp.org/) - there are like
+10 of them. But that's boring. Let's do it with the command line instead.
+
+## ImageMagick
+
+The obvious question is: how do we even edit an image file
+with the command line? Luckily, there is a tool for that:
+[ImageMagick](https://imagemagick.org/). This piece of software
+does a ton of things, and I do not use it very often. So I always
+need to look up what I want to do.
+
+One way to invoke ImageMagick is by calling the `convert` command,
+which can take a
+[`-resize`](https://imagemagick.org/script/command-line-options.php#resize)
+option, followed by a
+[`geometry`](https://imagemagick.org/script/command-line-processing.php#geometry)
+argument. After checking the online manual, I understood that the
+command I was looking for was:
+
+```
+$ convert picture.jpg -resize "750>" picture.jpg
+```
+
+which resizes `picture.jpg` by scaling it down to at most 750px width -
+keeping the ratio between width and height, and leaving it untouched if it
+is already smaller. The value 750 was chosen after a couple of attempts,
+it seems a good compromise between quality and size.
+
+And now I just have to do this for all the pictures. Of course, running
+the same command 10 times with a different argument is out of question.
+
+## find(1)
+
+*(No "man page reading club" this time, but don't
+worry, the series will be back soon.)*
+
+A standard UNIX command, [`find`](https://man.openbsd.org/find) allows
+you to scan a folder for files with certain properties (for example,
+a certain name pattern) and perform actions on them (for example,
+running a command). The OpenBSD and GNU versions of find have some
+differences, check your local manual page. The commands I use
+here have been tested on the GNU version, but should be standard.
+
+To look for file and simply print their name, we can use `-name`:
+
+```
+$ find src -name \*.jpg -or -name \*.png
+src/me.png
+src/favicon.png
+src/speedcubing/cubing.png
+src/blog/2023-01-28-windows-desktop/settings.png
+src/blog/2023-01-28-windows-desktop/tiling.png
+src/blog/2022-09-10-netbooks/darkstar.jpg
+src/blog/2022-09-10-netbooks/final.jpg
+src/blog/2022-09-10-netbooks/scramble.jpg
+src/blog/2022-09-10-netbooks/hd.jpg
+src/blog/2023-02-25-job-control/jobs-diagram.png
+src/blog/2022-12-30-blog-ready/pc-planner.jpg
+```
+
+Now we can use `-exec` to run a command on each of these files,
+using `{}` to refer to the file's name:
+
+```
+find src \( -name \*.jpg -or -name \*.png \) -exec convert {} -resize "750>" {} \;
+```
+
+We get a couple of warnings about grayscale images, but whatever.
+This seems to have worked.
diff --git a/src/blog/blog.md b/src/blog/blog.md
@@ -5,6 +5,7 @@
## 2023
+* 2023-03-06 [Resizing my website's pictures with ImageMagick and find(1)](2023-03-06-resize-pictures)
* 2023-02-25 [Job control: one shell is all you need](2023-02-25-job-control)
* 2023-01-28 [The year of the Windows desktop](2023-01-28-windows-desktop)
* 2023-01-11 [Aaron Swartz](2023-01-11-aaron-swartz)
diff --git a/src/blog/feed.xml b/src/blog/feed.xml
@@ -9,6 +9,13 @@ Thoughts about software, computers and whatever I feel like sharing
</description>
<item>
+<title>Resizing my website's pictures with ImageMagick and find(1)</title>
+<link>https://sebastiano.tronto.net/blog/2023-03-06-resize-pictures</link>
+<description>Resizing my website's pictures with ImageMagick and find(1)</description>
+<pubDate>2023-03-06</pubDate>
+</item>
+
+<item>
<title>Job control: one shell is all you need</title>
<link>https://sebastiano.tronto.net/blog/2023-02-25-job-control</link>
<description>Job control: one shell is all you need</description>
diff --git a/src/favicon.png b/src/favicon.png
Binary files differ.
diff --git a/src/me.png b/src/me.png
Binary files differ.
diff --git a/src/speedcubing/cubing.png b/src/speedcubing/cubing.png
Binary files differ.
