How to go from sketch to HTML5 canvas

0. Create sketch using paper and pen. (Pigma Micron 01 ink on 100 gsm paper in this case)
1. Take photo of sketch. (Using a Google Nexus S phone in this case)
2. Crop image, size it, and save it as a bitmap. (Paint.NET in this case)
3. Convert BMP format to SVG using potrace

@echo off
rem Batch file for automating SVG from BMP

if not "%~x1"==".bmp" goto :MustBeBitmap

mkbitmap -f 2 -s 1 -t 0.48 -o "%~n1.pnm" %1

potrace --svg -o "%~n1.svg" "%~n1.pnm"

goto :eof

:MustBeBitmap
echo You must provide a bitmap file (.bmp)