Merge branch 'documentation-updates'

* documentation-updates:
  DOCS: minor updates
  DOCS: describe the limiter used while mixing
  DOCS: add a few details describing the synchronization
  DOCS: update audiowmark help
  BUILD: include all files required to build documentation in EXTRA_DIST
  DOCS: document patchwork algorithm
Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

docs/Makefile.am

@@ -4,12 +4,16 @@ doc_DATA  = audiowmark.pdf audiowmark.html
 
 GRAPHVIZ_PY = graphviz.py
 
-audiowmark.pdf: audiowmark.md $(GRAPHVIZ_PY)
+EXTRA_DIST = audiowmark.md $(GRAPHVIZ_PY) example-spectrum.dat example-spectrum.gp
+
+audiowmark.pdf: audiowmark.md $(GRAPHVIZ_PY) example-spectrum.png
 	pandoc -F $(GRAPHVIZ_PY) -V papersize:a4 -V geometry:margin=2cm $< -o $@
 
-audiowmark.html: audiowmark.md $(GRAPHVIZ_PY)
+audiowmark.html: audiowmark.md $(GRAPHVIZ_PY) example-spectrum.png
 	pandoc -F $(GRAPHVIZ_PY) $< -o $@
 
+example-spectrum.png: example-spectrum.dat example-spectrum.gp
+	gnuplot example-spectrum.gp
 # DEPS: apt install -y python3-pygraphviz python3-pandocfilters
 
 clean:

docs/example-spectrum.dat

+1 10513 3
+2 13061 2
+3 11180 1
+4 8732 2
+5 13586 3
+6 14266 1
+7 14647 1
+8 7102 3
+9 16472 2
+10 6856 2
+11 13923 1
+12 16685 2
+13 16025 3
+14 16708 3
+15 11310 1
+16 16395 3

docs/example-spectrum.gp

+set terminal pngcairo size 800,450
+set output 'example-spectrum.png'
+
+# Set bar width
+set boxwidth 0.5
+set style fill solid border -1
+set linetype 1 lc rgb "#990000" lw 1
+set linetype 2 lc rgb "#009900" lw 1
+set linetype 3 lc rgb "#666666" lw 1
+
+set arrow from graph 0,1 to graph 0,1.1 filled
+set arrow from graph 1,0 to graph 1.1,0 filled
+set tmargin 5
+set rmargin 10
+set border 3
+set tics nomirror
+set noxtics
+set noytics
+set grid
+set ylabel "Magnitude"
+set xlabel "Frequency"
+
+# Set the range for y-axis
+set yrange [0:*]
+
+# Plot the data with different colors
+plot "example-spectrum.dat" using 1:2:3 with boxes lc variable notitle, \
+     "<grep '1$' example-spectrum.dat" u 1:2:(0):(1500) with vectors lc 1 notitle, \
+     "<grep '2$' example-spectrum.dat" u 1:($2+1500):(0):(-1500) with vectors lc 2 notitle