From 2ff480a3650079a50bac4c9bf538f788fbd4a424 Mon Sep 17 00:00:00 2001
From: Florian Moser <git@famoser.ch>
Date: Sun, 28 Mar 2021 21:38:39 +0200
Subject: [PATCH] Working on PDF course
---
pdf/css/remark.css | 4 +
pdf/image.pdf | 3 +
pdf/pdf.html | 193 +++++++++++++++++++++++++++++++++----
pdf/rectangle.pdf | 3 +
pdf/special_characters.pdf | 3 +
pdf/text.pdf | 3 +
6 files changed, 190 insertions(+), 19 deletions(-)
create mode 100644 pdf/image.pdf
create mode 100644 pdf/rectangle.pdf
create mode 100644 pdf/special_characters.pdf
create mode 100644 pdf/text.pdf
diff --git a/pdf/css/remark.css b/pdf/css/remark.css
index cdb2ed8..26103fd 100644
--- a/pdf/css/remark.css
+++ b/pdf/css/remark.css
@@ -36,3 +36,7 @@ table thead th {
border-bottom: 2px solid #dee2e6;
vertical-align: bottom;
}
+
+.space-3 {
+ margin-top: 5em
+}
\ No newline at end of file
diff --git a/pdf/image.pdf b/pdf/image.pdf
new file mode 100644
index 0000000..df91e0e
--- /dev/null
+++ b/pdf/image.pdf
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:7cb7c68d9d8490dbb8c319f7be1fe3a2992aecb15707a6662ae7210fb9ca5b2f
+size 1411
diff --git a/pdf/pdf.html b/pdf/pdf.html
index 20288e2..590d013 100644
--- a/pdf/pdf.html
+++ b/pdf/pdf.html
@@ -56,18 +56,16 @@ Acrobat Distiller (network version): 2495$
---
-# Releases
-
-| | Year | Industry | Notable features |
-| --- | :--- | :------- | :--------------- |
-| 1.0 | 1993 | Adobe | **text**, **images**, **pages**, **hyperlinks**, bookmarks |
-| 1.1 | 1994 | Tax | passwords, encryption, device-independent color |
-| 1.2 | 1996 | Printing | radio buttons, checkboxes, forms incl. import/export, mouse events, sound, **unicode**, color features |
-| 1.3 | 2000 | Printing | digital signatures, color spaces, JavaScript, embedded file streams, image utilities, **CIDFonts**, prepress support |
-| 1.4 | 2001 | | RC4 > 40bits, transparency, better forms, metadata, accessibility, page boundaries, printer marks, predefined CMaps |
-| 1.5 | 2003 | | jpeg, multimedia playback, better forms, public key encryption, permissions, view/hide layers, slideshow |
-| 1.6 | 2004 | | 3D, **OpenType**, SOAP over http, public key encryption improvements, color spaces |
-| 1.7 | 2006 | | 3D improvements, public key encryption improvements |
+| | Year | Industry | Notable features |
+| ---- | :--- | :------- | :--------------- |
+| v1.0 | 1993 | Adobe | **text**, **images**, **pages**, **hyperlinks**, bookmarks |
+| v1.1 | 1994 | Tax | passwords, encryption, device-independent color |
+| v1.2 | 1996 | Printing | radio buttons, checkboxes, forms incl. import/export, mouse events, sound, **unicode**, color features |
+| v1.3 | 2000 | Printing | digital signatures, color spaces, JavaScript, embedded file streams, image utilities, **CIDFonts**, prepress support |
+| v1.4 | 2001 | | RC4 > 40bits, transparency, better forms, metadata, accessibility, page boundaries, printer marks, predefined CMaps |
+| v1.5 | 2003 | | jpeg, multimedia playback, better forms, public key encryption, permissions, view/hide layers, slideshow |
+| v1.6 | 2004 | | 3D, **OpenType**, SOAP over http, public key encryption improvements, color spaces |
+| v1.7 | 2006 | | 3D improvements, public key encryption improvements |
*Version 1.7 is ISO 32000-1:2008.*
@@ -110,18 +108,175 @@ PDF/A Subversions:
# Why is it so popular?
Single purpose, which is archived:
-**It display content equally on all devices.**
+**It displays content equally on all devices.**
-Comparison to web:
-- Need to increase readability on smaller screens (font size, colors, spacing, ...)
-- Need to handle different aspect ratios
-- Optimize for less powerful devices
-- [Can I Use](https://caniuse.com/) tries to track browser inconsistencies
+<div class="space-3"></div>
+
+Comarison: How webpages deal with different devices:
+- Adapt font size, colors, spacing, ... to screen size
+- Adapt layout to aspect ratio / screen size
+- Remove or add elements depending on end device
+- Test on end devices and/or use resources such as [Can I Use](https://caniuse.com/)
+
+In short: Its painful and slow.
+
+---
+
+class: center, middle
+
+# The file format
+
+---
+
+# Tokens
+
+PDF is a text format. You can open any PDF in your text editor!
+
+Tokens:
+```html
+0 % Numbers
+Hello % Strings
+5 0 R % References (5 for the object number, 0 for its generation number, R for reference)
+[2 0 R] % Arrays
+<</Key /Value>> % Dictionaries
+Image % Names (any two with the same content are "equal")
+```
+
+Out of these tokens, the higher-level objects are composed
+- Dictionaries
+- Streams
---
-# The PDF format
+# Structure (1/2)
+
+Header (asserts PDF version and wether binary data is contained)
+```html
+%PDF-1.7
+%����
+```
+
+Body (contains the actual content)
+```html
+1 0 obj
+<</Type /Catalog /Pages 2 0 R>>
+endobj
+2 0 obj
+<</Type /Pages /Kids [3 0 R] /Count 1>>
+endobj
+% ...
+```
+
+---
+
+# Structure (2/2)
+
+Cross-Reference Table (CRT) (contains the binary offset of objects)
+```html
+xref
+0 8
+0000000000 65535 f
+0000000015 00000 n
+0000000062 00000 n
+% ...
+```
+
+Trailer (contains size of CRT and reader start points)
+```html
+trailer
+<</Size 8 /Root 1 0 R /Info 7 0 R>>
+startxref
+574
+%%EOF
+```
+
+---
+
+# Body
+
+```html
+1 0 obj
+<</Type /Catalog /Pages 2 0 R>>
+endobj
+2 0 obj
+<</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]>>
+endobj
+4 0 obj
+<</Font <</F 5 0 R>> /ProcSet [/PDF /Text]>>
+endobj
+5 0 obj
+<</Type /Font /Subtype /Type1 /BaseFont /Helvetica /Encoding /WinAnsiEncoding>>
+endobj
+6 0 obj
+<</Length 59>>
+stream
+BT 1 0 0 1 22 20 cm 1 w /F 12 Tf 14.4 TL (Hello world)Tj ET
+endstream
+endobj
+```
+
+---
+
+# Content
+
+Text (`w` = line width, `Tf` = font, `TL` = leading, `Tj` = text)
+```html
+stream
+BT 1 0 0 1 22 20 cm 1 w /F 12 Tf 14.4 TL (Hello world)Tj ET
+endstream
+```
+
+Drawing (`RG` = line color, `rg` = background color, `re` = rectangle, `b` = painting mode)
+```html
+stream
+1 0 0 1 40 20 cm 0.5 w 0.68 0.98 0.94 RG 0.67 0.8 0.73 rg 0 0 20 30 re b
+endstream
+```
+
+---
+
+# Image
+
+Stream with binary image data
+
+```html
+5 0 obj
+<</Length 570 /Type /XObject /Subtype /Image /Width 25 /Height 16 /Filter /DCTDecode /BitsPerComponent 8 /ColorSpace /DeviceRGB>>
+stream
+�����JFIF���������#�#�#�#�%�#�'�+�+�'�6�;�4�;�6�P�J�C�C�J�P�z�W�]�W�]�W�z���s���s�s���s����������������%��������%S
+ S�oo������#�#�#�#�%�#�'�+�+�'�6�;�4�;�6�P�J�C�C�J�P�z�W�]�W�]�W�z���s���s�s���s����������������%��������%S
+ S�oo����������"��������������������������̊ �N�������������������������k���������������������������"������������"CRSb�����?� �`W�F�X�6�G�Qy&IXFĪ��V�to������������������A���?�zе]������������������Q���?�S�����
+endstream
+endobj
+```
+
+Print image (`Do` = print referenced image)
+```html
+6 0 obj
+<</Length 28>>
+stream
+20 0 0 20 20 20 cm 1 w /I Do
+endstream
+endobj
+```
+
+---
+
+# Supporting unicode
+
+`WinAnsiEncoding` is a single byte encoding; so are the other default encodings.
+
+What if I need a character not contained in these standard encodings (like chinese characters)?
+
+Steps:
+- Embedd font which supports character as stream
+- Declare encoding of text (PDF) onto glyphs (font)
+- Declare meta data (widths of characters, ...)
+=> Requires deep knowledge about font
---
diff --git a/pdf/rectangle.pdf b/pdf/rectangle.pdf
new file mode 100644
index 0000000..ab73c13
--- /dev/null
+++ b/pdf/rectangle.pdf
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:a36378ab20ce0579de369f809130f2b7af192870bfeef01486c6b91e192ed3df
+size 786
diff --git a/pdf/special_characters.pdf b/pdf/special_characters.pdf
new file mode 100644
index 0000000..38fefd8
--- /dev/null
+++ b/pdf/special_characters.pdf
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:fb4219346e7aff1c1f04369def800cfd88dcce46a4ac6d4f5e5ed308051e9ab8
+size 7531
diff --git a/pdf/text.pdf b/pdf/text.pdf
new file mode 100644
index 0000000..76d3afd
--- /dev/null
+++ b/pdf/text.pdf
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:ee782f47771c1a0d6cafcf4a08c8c628b41fe3ff29704db5124a5e21ca802eaa
+size 806
--
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