From 982d61b3faa3207f5e7c6dd9d0b7af408cd80a08 Mon Sep 17 00:00:00 2001
From: Natalia Portillo <claunia@claunia.com>
Date: Thu, 31 Jul 2025 21:36:10 +0100
Subject: [PATCH] [Specification] Add compression types appendix

---
 docs/spec/appendixes/compression.adoc | 18 ++++++++++++++++++
 docs/spec/spec.adoc                   |  6 +++++-
 2 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 docs/spec/appendixes/compression.adoc

diff --git a/docs/spec/appendixes/compression.adoc b/docs/spec/appendixes/compression.adoc
new file mode 100644
index 0000000..0608d07
--- /dev/null
+++ b/docs/spec/appendixes/compression.adoc
@@ -0,0 +1,18 @@
+[appendix]
+== Compression Types
+
+This apprendix lists all supported compression algorithms used within AaruFormat images.
+
+NOTE: Compression method definitions may evolve over time.
+For the latest and most accurate listing, refer to the `libaaruformat` source.
+
+[cols="1,5",options="header"]
+|===
+|Value
+|Algorithm
+
+|0 |None
+|1 |LZMA — stream prepended by 5 bytes of parameters
+|2 |FLAC
+|3 |LZMA after Claunia Subchannel Transform (see Appendix D) — stream prepended by 5 bytes of parameters
+|===
diff --git a/docs/spec/spec.adoc b/docs/spec/spec.adoc
index 17cec9b..403445c 100644
--- a/docs/spec/spec.adoc
+++ b/docs/spec/spec.adoc
@@ -126,4 +126,8 @@ include::appendixes/media_types.adoc[]
 
 <<<
 
-include::appendixes/data_types.adoc[]
\ No newline at end of file
+include::appendixes/data_types.adoc[]
+
+<<<
+
+include::appendixes/compression.adoc[]
\ No newline at end of file