From 17c4648064adc1ec718ee5b31ab6f825455042fe Mon Sep 17 00:00:00 2001
From: Martin Thoma <info@martin-thoma.de>
Date: Sun, 24 Apr 2022 17:15:49 +0200
Subject: [PATCH] DOC: PDF feature/version support (#816)

---
 .github/workflows/github-ci.yaml |  6 ++++++
 docs/index.rst                   |  1 +
 docs/user/pdf-version-support.md | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 docs/user/pdf-version-support.md

diff --git a/.github/workflows/github-ci.yaml b/.github/workflows/github-ci.yaml
index 6fe34071a..a47241ed6 100644
--- a/.github/workflows/github-ci.yaml
+++ b/.github/workflows/github-ci.yaml
@@ -6,8 +6,14 @@ name: CI
 on:
   push:
     branches: [ main ]
+    paths-ignore:
+      - '**/*.md'
+      - '**/*.rst'
   pull_request:
     branches: [ main ]
+    paths-ignore:
+      - '**/*.md'
+      - '**/*.rst'
 
 jobs:
   tests:
diff --git a/docs/index.rst b/docs/index.rst
index 90db760e4..4884e960d 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -31,6 +31,7 @@ You can contribute to `PyPDF2 on Github <https://github.com/py-pdf/PyPDF2>`_.
    user/forms
    user/streaming-data
    user/file-size
+   user/pdf-version-support
 
 
 .. toctree::
diff --git a/docs/user/pdf-version-support.md b/docs/user/pdf-version-support.md
new file mode 100644
index 000000000..a588997ab
--- /dev/null
+++ b/docs/user/pdf-version-support.md
@@ -0,0 +1,32 @@
+# PDF Version Support
+
+PDF comes in the following versions:
+
+* 1993: 1.0
+* 1994: 1.1
+* 1996: 1.2
+* 1999: 1.3
+* 2001: 1.4
+* 2003: 1.5
+* 2004: 1.6
+* 2006 - 2012: 1.7, ISO 32000-1:2008
+* 2017: 2.0
+
+The general format didn't change, but new features got added. It can be that
+PyPDF2 can do the operations you want on PDF 2.0 files without fully supporting
+all features of PDF 2.0.
+
+## PDF Feature Support by PyPDF2
+
+| Feature                                 | PDF-Version | PyPDF2 Support |
+| --------------------------------------- | ----------- | -------------- |
+| Transparent Graphics                    | 1.4         | ?              |
+| CMaps                                   | 1.4         | ❌ [#201](https://github.com/py-pdf/PyPDF2/pull/201), [#464](https://github.com/py-pdf/PyPDF2/pull/464), [#805](https://github.com/py-pdf/PyPDF2/pull/805)   |
+| Object Streams                          | 1.5         | ?              |
+| Cross-reference Streams                 | 1.5         | ?              |
+| Optional Content Groups (OCGs) - Layers | 1.5         | ?              |
+| Content Stream Compression              | 1.5         | ?              |
+| AES Encryption                          | 1.6         | ❌ [#749](https://github.com/py-pdf/PyPDF2/pull/749)  |
+
+See [History of PDF](https://en.wikipedia.org/wiki/History_of_PDF) for more
+features.