{
  "analysis": "The output is even larger now. The issue is that I'm using absolute positioning for every single change. I need to be smarter about choosing between EL+rewrite and partial updates. Let me calculate the optimal threshold.",
  "plan": "Calculate the optimal threshold for EL+rewrite vs partial updates and implement it properly.",
  "commands": [
    {
      "keystrokes": "python3 << 'EOF'\nimport struct\n\nwith open('/app/frames.tza', 'rb') as f:\n    f.read(4)\n    w, h = struct.unpack('<HH', f.read(4))\n    n_frames, max_bytes = struct.unpack('<II', f.read(8))\n    frames = [f.read(w*h) for _ in range(n_frames)]\n\ndef find_runs(changes):\n    runs = []\n    if not changes:\n        return runs\n    run_start = changes[0]\n    run_end = changes[0]\n    for c in changes[1:]:\n        if c == run_end + 1:\n            run_end = c\n        else:\n            runs.append((run_start, run_end))\n            run_start = run_end = c\n    runs.append((run_start, run_end))\n    return runs\n\n# Calculate optimal threshold\ndef pos_cost(r, c):\n    return 3 + len(str(r)) + 1 + len(str(c))\n\n# For a row at position r:\n# EL+rewrite: pos_cost(r+1, 1) + 4 + w\n# Partial: sum(pos_cost(r+1, start+1) + run_len for each run)\n\ndef cost_erase(r):\n    return pos_cost(r+1, 1) + 4 + w\n\ndef cost_partial(r, changes):\n    runs = find_runs(changes)\n    return sum(pos_cost(r+1, start+1) + (end-start+1) for start, end in runs)\n\n# Test with row 2 from frame 7 (30 changes, 2 runs)\ni = 7\nr = 13\nprev_row = frames[i-1][r*w:(r+1)*w]\ncurr_row = frames[i][r*w:(r+1)*w]\nchanges = [c for c in range(w) if prev_row[c] != curr_row[c]]\nprint(f'Row {r}: {len(changes)} changes')\nprint(f'  Erase cost: {cost_erase(r)}')\nprint(f'  Partial cost: {cost_partial(r, changes)}')\n\n# Find the crossover threshold\nprint(f'\\nFor row {r}:')\nprint(f'  Erase cost: {cost_erase(r)}')\nprint(f'  Cost per change position + 1 char: ~{pos_cost(r+1, 10) + 1}')\nprint(f'  Crossover at ~{cost_erase(r) // (pos_cost(r+1, 10) + 1)} changes')\nEOF\n",
      "duration": 3.0
    }
  ]
}