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@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:38cf564a75bcaad9c87d0de8f4d5f4572037bd2be510282dccb8c9b51c09bc38
+size 469552
diff --git a/pdf/images/max_page_size.png b/pdf/images/max_page_size.png
new file mode 100644
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+version https://git-lfs.github.com/spec/v1
+oid sha256:70056b7564b7a805df4ddb123d6b55d51e0a439b8cac375f478f0e647094c0db
+size 654891
diff --git a/pdf/pdf.html b/pdf/pdf.html
index 9f34d859223fb87e2859294c24497395da35e71e..f6a6f1fdbeb76fc11cc17cc08a059cc17ceb87c9 100644
--- a/pdf/pdf.html
+++ b/pdf/pdf.html
@@ -19,6 +19,38 @@ class: center, middle
 
 ---
 
+# Portable Document Format
+
+<img src="images/max_page_size.jpg" width="100%">
+
+Max page size of PDF: 381 km × 381 km
+
+
+---
+
+# Structure of this talk
+
+PDF introduction:
+- PDF history
+- PDF standards
+- PDF file format
+
+Text rendering:
+- PDF text display
+- TTF file format
+
+(My) new ideas:
+- PDF & TFF writer
+- Reflection
+
+---
+
+class: center, middle
+
+# PDF History and Standards
+
+---
+
 # PostScript
 
 Somewhat the predecessor of PDF, created by the same company, Adobe.  
@@ -112,8 +144,9 @@ PDF/A Subversions:
 Single purpose, which is archived:  
 **It displays content equally on all devices.**
 
-<img src="images/sizing.png" width="60%">
+<img src="images/sizing.png" width="50%">
 
+<hr/>
 Comparison: How webpages deal with different devices:
 - Adapt font size, colors, spacing, ... to screen size
 - Adapt layout to aspect ratio / screen size
@@ -214,7 +247,7 @@ endobj
 <</Type /Pages /Kids [3 0 R] /Count 1>>
 endobj
 3 0 obj
-<</Type /Page /Parent 2 0 R /Resources 4 0 R /MediaBox [0 0 210 297] /Contents [6 0 R]>>
+<</Type /Page /Parent 2 0 R /MediaBox [0 0 210 297] /Resources 4 0 R /Contents [6 0 R]>>
 endobj
 4 0 obj
 <</Font <</F 5 0 R>> /ProcSet [/PDF /Text]>>
@@ -294,6 +327,22 @@ class: center, middle
 
 <i>Or: What is the most complicated approach to "support" unicode?</i>
 
+---
+
+# Crashcourse encoding
+
+Character: Letters / numbers ("what you see"); like 2, a, A, {, $  
+Encoding: Defines how bits are mapped to characters
+
+| Character | UTF-8 Encoding | UTF-16 Encoding | (decimal)
+| :--- | :--- | :--- | :--- | :--- |
+| 2 | 0010 1000 | 0000 0000 0010 1000 | 32
+| a | 0011 1101 | 0000 0000 0011 1101 | 61
+| A | 0010 1001 | 0000 0000 0010 1001 | 41
+
+Unicode: Maps decimals to characters. *huge*: March 2020, 143,859 characters defined.
+
+
 ---
 
 # Text with default encoding / fonts