)]}'
{
  "commit": "984734436d8f13fc44ca3f0f3d65e0d057d6fd20",
  "tree": "c73a2ac7047b86d5752ae234e7b6ff76a6af4912",
  "parents": [
    "a879b4e6d425e7ec26e6ed9f0ef3e84575a891d4"
  ],
  "author": {
    "name": "James Zern",
    "email": "jzern@google.com",
    "time": "Tue Nov 06 16:58:11 2012 -0800"
  },
  "committer": {
    "name": "James Zern",
    "email": "jzern@google.com",
    "time": "Tue Nov 06 23:06:44 2012 -0800"
  },
  "message": "Fix variance (signed integer) overflow\n\nIn the variance calculations the difference is summed and later squared.\nWhen the sum exceeds sqrt(2^31) the value is treated as a negative when\nit is shifted which gives incorrect results.\n\nTo fix this we force the multiplication to be unsigned.\n\nThe alternative fix is to shift sum down by 4 before multiplying.\nHowever that will reduce precision.\n\nFor 16x16 blocks the maximum sum is 65280 and sqrt(2^31) is 46340 (and\nchange).\n\nThis change is based on:\n1698234 Missed some variance casts\nfea3556 Fix variance overflow\n\nChange-Id: I2c61856cca9db54b9b81de83b4505ea81a050a0f\n",
  "tree_diff": [
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