1. Motivation

1. I'm a programmer by trade.
2. Looked at the code I wrote in past.
3. "What the #$%& was I thinking!?"
4. Wanted to dissect my own brain.

2. Two Ways

1. Make a time machine.
   or...
2. Record everything and retrieve them later.
   - Code, monologue and reaction.

Issues of Record Everything

• Coding sessions are long.
  (Data size: 50GB for 8hrs. = non issue!)
• Painful to find a right spot from hours of recording.

Proposed Method

• A way to trace back from the finished source code to the moment it was written.
• Demo!

3. What We Did

• Built a system that records a programmer's environment (Screencap + Webcam) during coding.
• Provides mappings from source code to video.
• Optionally, provides emotion analysis.
  (via external API)

System Overview

4. Problem

• Source codes are often moved/removed/copied.
• 1-to-1 mapping doesn't exist!
  Text:

  int a=456123;
  

  Actual keystrokes:
  b = 1 2 3 4 5 6 C-a i n t Space C-f C-h a C-e ; C-b C-b C-b C-b M-d M-b C-y

Algorithm

• Input 1: k_i ∈ K (Keystrokes)
• Input 2: t_j ∈ T (Text)
• Output: M = {k_i → t_j}

Algorithm (cont'd)

1. Unique sequence k_i and t_j should be matched.
2. Consecutive keystrokes are likely to appear as consecutive characters.
3. By grouping keystroke/text pairs, we'll get a longer unique sequence.

5. Implementation

• Keylogger (Win32 and Mac).
• Sequence matcher.
• HTML5 video player.

  Code: https://github.com/euske/codecam/

6. Experiments

1. Project Euler #89
2. Make an HTML5 game
3. Advent of Code 2017 - Day 18

• Precision: 71%
• Recall: 21% (copy-and-paste not recorded!)

Sample output

7. Emotion Analysis (Optional)

• Feed facial images to Microsoft Emotion API.
• Gives probabilities for each image:
  "happiness", "anger", "contempt", "disgust", "fear", "sadness", "surprise" or "neutral".
• Problem: mostly recognized as "neutral" or "happiness".

8. Conclusions

• Built a system that captures programmer's reaction.
  - Emotionless most of time.
  - Any emotion = notable.
  
• Demonstrated its usefulness.
  - This is the future!

9. Comments from Reviewers

1. "Why not make an IDE plugin?"
   - Applicable to any editor/IDE.
   - We could record interactions outside the editor.
2. "Filming everything is not acceptable."
   - Programmers should be held responsible.
   - Hawthone effect?
3. "This is better suited to education!"
   - We're working on it!