README.md: add img minification

1 files changed, 14 insertions, 0 deletions

diff --git a/README.md b/README.md
index 6a2c53a..42cf3cc 100644
--- a/README.md
+++ b/README.md
@@ -83,6 +83,16 @@ To serve this site locally:
 * `--disableFastRenderer` may be unnecessary, but the fast
   renderer cache was giving me grief while doing theme development.
 
+## Minify Images
+
+Notes:
+
+1. Use `svgmin` to shrink [SVGs][svg].
+2. Use `convert -quality 100 -define web:lossless=true foo.{png,webp}`
+   to compress existing PNGs as `webp`s.
+3. Use the `pe-figure` shortcode for progressive enhanced `figure` tags
+   with a fallback image.
+
 ## Deploy Site
 
 To clone site repo:
@@ -119,6 +129,8 @@ Includes the following shortcodes:
 * `table`: Enhanced [CSS][]-only table shortcode.  See
   [hugo-shortcode-table][].
 * `sup`: Superscript.
+* `pe-picture`: Progressive enhancement `picture` shortcode.
+* `pe-figure`: Progressive enhancement `figure` shortcode.
 
 `hugo-pt2021` is depends on the following:
 
@@ -164,3 +176,5 @@ The [Bulma][] [SASS][] is:
   "Scalable Vector Graphics"
 [hugo-shortcode-table]: https://github.com/pablotron/hugo-shortcode-table
   "CSS-only table shortcode for Hugo."
+[hugo-shortcode-pe]: https://github.com/pablotron/hugo-shortcode-pe
+  "Progressive enhancement picture and figure shortcodes for Hugo."