Here is a simple ruby script that I used to get author, lines added, lines removed, and commit count from git. It does not cover commits over time.
Note that I have a trick where it ignores any commit that adds/removes more than 10,000 lines because I assume that this is a code import of some sort, feel free to modify the logic for your needs. You can put the below into a file called gitstats-simple.rb and then run
git log --numstat --pretty='%an' | ruby gitstats-simple.rb
contents of gitstats-simple.rb
#!/usr/bin/ruby
# takes the output of this on stdin: git log --numstat --prety='%an'
map = Hash.new{|h,k| h[k] = [0,0,0]}
who = nil
memo = nil
STDIN.read.split("\n").each do |line|
parts = line.split
next if parts.size == 0
if parts[0].match(/[a-z]+/)
if who && memo[0] + memo[1] < 2000
map[who][0] += memo[0]
map[who][1] += memo[1]
map[who][2] += 1
end
who = parts[0]
memo = [0,0]
next
end
if who
memo[0]+=line[0].to_i
memo[1]+=parts[1].to_i
end
end
puts map.to_a.map{|x| [x[0], x[1][0], x[1][1], x[1][2]]}.sort_by{|x| -x[1] - x[2]}.map{|x|x.inspect.gsub("[", "").gsub("]","")}.join("\n")