The final input data format is like this:
{
    "stack_trace": "CRASHED [EXCEPTION_BREAKPOINT @ 0x7fee53fa96d]\n#0 ...",    
    "chrome_version": "52.0.2729.0", 
    "customized_data": {
        "historic_metadata": [ 
            {"chrome_version": "52.0.2727.0", "cpm": 0.00082153819999999998}, 
            {"chrome_version": "52.0.2728.0", "cpm": 0.00094132109999999999},   
            {"chrome_version": "52.0.2729.0", "cpm": 0.00054054319999999995}
         ], 
        "channel": "canary"
    }, 
    "platform": "win", 
    "client_id": "fracas", 
    "signature": "[Out of Memory] content::`anonymous namespace'::CollectMemoryUsageAndDie", 
    "crash_identifiers": {
        "platform": "win", 
        "chrome_version": "52.0.2729.0", 
        "process_type": "renderer", 
        "channel": "canary", 
        "signature": "[Out of Memory] content::`anonymous namespace'::CollectMemoryUsageAndDie"
    }
}

Final output data format is like this:
{
  "crash_identifiers": {
    "platform": "win",
    "chrome_version": "51.0.2695.1",
    "process_type": "renderer",
    "channel": "canary",
    "signature": "blink::FramePainter::paintContents"
  },
  "client_id": "fracas",
  "result": {
    "found": true,
    "suspected_project": "chromium",
    "suspected_cls": [
      {
        "reason": "1. Top frame changed is frame #0 (score: 1)\n2. Minimum distance to crashed line is 0 (score: 1)\nChanged file api.cc crashed in run (#0), func2 (#3)",
        "project_path": "third_party/pdfium",
        "time": "2015-08-17 03:38:16",
        "author": "who@chromium.org",
        "url": "https://chromium.googlesource.com/chromium/src/+/commit-hash",
        "project_name": "pdfium",
        "codereview_url": "https://codereview.chromium.org/issue-number",
        "confidence": 0.6,
        "revision": "commit-hash"
      }
    ],
    "suspected_components": [
      "Blink>Paint"
    ]
  }
}