<!-- Generated by SpecStory -->

# Video Processing Misalignment Issue (2025-05-25 01:49:33)

_**User**_

time python -m vidkompy --bg tests/bg.mp4 --fg tests/fg.mp4 -o tests/out-c2.mp4 --blend

The result is RIDICULOUSLY misaligned

---

_**Assistant**_



---

I'll help you diagnose and fix the misalignment issue. Let me first examine the current codebase to understand what's happening with the alignment logic.

---

<details>
            <summary>Listed directory src • **1** results</summary>
        
| Name |
|-------|
| 📁 `vidkompy` |

</details>

---

<details>
            <summary>Listed directory src/vidkompy • **8** results</summary>
        
| Name |
|-------|
| 📁 `__pycache__` |
| 📄 `vidkompy.py` |
| 📄 `models.py` |
| 📄 `__version__.py` |
| 📁 `core` |
| 📄 `__init__.py` |
| 📄 `__main__.py` |
| 📄 `.DS_Store` |

</details>

---

Read file: src/vidkompy/vidkompy.py

---

Now let me check the core implementation files to understand the alignment logic:

---

<details>
            <summary>Listed directory src/vidkompy/core • **9** results</summary>
        
| Name |
|-------|
| 📁 `__pycache__` |
| 📄 `spatial_alignment.py` |
| 📄 `video_processor.py` |
| 📄 `alignment_engine.py` |
| 📄 `temporal_alignment.py` |
| 📄 `frame_fingerprint.py` |
| 📄 `dtw_aligner.py` |
| 📄 `__init__.py` |
| 📄 `.DS_Store` |

</details>

---

Let me look at the alignment engine since that's where the main processing logic is:

---

Read file: src/vidkompy/core/alignment_engine.py

---

Let me check the spatial alignment logic and the frame overlay method to understand what might be causing the misalignment:

---

Read file: src/vidkompy/core/spatial_alignment.py

---

Now let me check the frame overlay logic to see how the spatial alignment is applied:

---

Read file: src/vidkompy/core/alignment_engine.py

---

Now let me look for the actual vidkompy_old.py file that was mentioned in the description to see if there's a different implementation being used:

---

<details>
            <summary>Searched codebase "vidkompy_old.py" • **0** results</summary>
        
No results found
</details>

---

<details>
            <summary>Grep search for "vidkompy_old" • **6** files</summary>
        
| File | Line | Match |
|------|------|-------|
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursor/rules/video-processing-flow.mdc` | L2 | `globs: src/vidkompy/vidkompy_old.py,src/vidkompy/core/*.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L120 | `python src/vidkompy/vidkompy_old.py --help|cat` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L122 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L125 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L128 | `vidkompy_old.py BG FG <flags>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L175 | `# Direct execution (main implementation in vidkompy_old.py)` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L181 | `1. **Main Implementation**: The core functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L232 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L239 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L245 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L251 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L257 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L265 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L271 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L120 | `python src/vidkompy/vidkompy_old.py --help|cat` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L122 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L125 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L128 | `vidkompy_old.py BG FG <flags>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L175 | `# Direct execution (main implementation in vidkompy_old.py)` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L181 | `1. **Main Implementation**: The core functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L244 | `Main Implementation (src/vidkompy/vidkompy_old.py):` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L709 | `python src/vidkompy/vidkompy_old.py --help|cat` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L711 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L714 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L717 | `vidkompy_old.py BG FG <flags>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L764 | `# Direct execution (main implementation in vidkompy_old.py)` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L770 | `1. **Main Implementation**: The core functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L821 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L828 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L834 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L840 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L846 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L854 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L860 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1083 | `python src/vidkompy/vidkompy_old.py --help|cat` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1085 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1088 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1091 | `vidkompy_old.py BG FG <flags>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1138 | `# Direct execution (main implementation in vidkompy_old.py)` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1144 | `1. **Main Implementation**: The core functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1195 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1202 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1208 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1214 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1220 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1228 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1234 | `- File: src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L73 | `⟪ 179 characters skipped ⟫project structure to see if there's an `vidkompy_old.py` file mentioned in the documentation:` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L78 | `<summary>Searched codebase "vidkompy_old.py" • **0** results</summary>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L108 | `<summary>Grep search for "vidkompy_old" • **4** files</summary>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L112 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L120 | `python src/vidkompy/vidkompy_old.py --help|cat` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L113 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L122 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L114 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L125 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L115 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L128 | `vidkompy_old.py BG FG <flags>` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L116 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/CLAUDE.md` | L175 | `# Direct execution (main implementation in vidkompy_old.py)` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L117 | `⟪ 122 characters skipped ⟫ functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L118 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L120 | `python src/vidkompy/vidkompy_old.py --help|cat` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L119 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L122 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L120 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L125 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L121 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L128 | `vidkompy_old.py BG FG <flags>` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L122 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursorrules` | L175 | `# Direct execution (main implementation in vidkompy_old.py)` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L123 | `⟪ 125 characters skipped ⟫ functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L124 | `⟪ 117 characters skipped ⟫bs: src/vidkompy/core/*.py,src/vidkompy/vidkompy_old.py` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L125 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.cursor/rules/video-processing-flow.mdc` | L54 | `└── vidkompy_old.py             # Main processing pipeline` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L126 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1014 | `globs: src/vidkompy/core/*.py,src/vidkompy/vidkompy_old.py` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L127 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L1066 | `└── vidkompy_old.py             # Main processing pipeline` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L128 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L2748 | `python src/vidkompy/vidkompy_old.py --help|cat` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L129 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L2750 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L130 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L2753 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L131 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L2756 | `vidkompy_old.py BG FG <flags>` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L132 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L2803 | `# Direct execution (main implementation in vidkompy_old.py)` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L133 | `⟪ 121 characters skipped ⟫ functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L134 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L3034 | `python src/vidkompy/vidkompy_old.py --help|cat` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L135 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L3036 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L136 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L3039 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L137 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L3042 | `vidkompy_old.py BG FG <flags>` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L138 | `| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/LLM.txt` | L3089 | `# Direct execution (main implementation in vidkompy_old.py)` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L139 | `⟪ 121 characters skipped ⟫ functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L146 | `<summary>Searched codebase "vidkompy_old.py" • **5** results</summary>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_14-20-fixing-todos-in-markdown-files.md` | L219 | `It looks like there is no `vidkompy_old.py` file in the current codebase. Based on my analysis of the current `alignment_engine.py`, I can see that the optimization described in the TODO has already been implemented!` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L307 | `globs: src/vidkompy/core/*.py,src/vidkompy/vidkompy_old.py` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L359 | `└── vidkompy_old.py             # Main processing pipeline` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L786 | `python src/vidkompy/vidkompy_old.py --help|cat` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L788 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L791 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L794 | `vidkompy_old.py BG FG <flags>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L841 | `# Direct execution (main implementation in vidkompy_old.py)` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L847 | `1. **Main Implementation**: The core functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L1072 | `python src/vidkompy/vidkompy_old.py --help|cat` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L1074 | `INFO: Showing help with the command 'vidkompy_old.py -- --help'.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L1077 | `vidkompy_old.py - Overlay foreground video onto background video with intelligent alignment.` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L1080 | `vidkompy_old.py BG FG <flags>` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L1127 | `# Direct execution (main implementation in vidkompy_old.py)` |
| `file:///Users/adam/Developer/vcs/github.twardoch/pub/vidkompy/.specstory/history/2025-05-24_22-29-chat-name-generation.md` | L1133 | `1. **Main Implementation**: The core functionality resides in `src/vidkompy/vidkompy_old.py` (60KB).` |

</details>

---

It seems the documentation refers to `vidkompy_old.py` but it doesn't exist. Let me check if the actual command is using the new implementation. First, let me look at the `__main__.py` to see what's being executed:

---

Read file: src/vidkompy/__main__.py

---

Now let me run the command with verbose output to see what's happening during alignment:

---

```bash
cd /Users/adam/Developer/vcs/github.twardoch/pub/vidkompy && python -m vidkompy --bg tests/bg.mp4 --fg tests/fg.mp4 -o tests/out-debug.mp4 --blend --verbose
```

```
adam@Hamlet vidkompy % cd /Users/adam/Developer/vcs/github.twardoch/pub/vidkomp
y && python -m vidkompy --bg tests/bg.mp4 --fg tests/fg.mp4 -o tests/out-debug.
mp4 --blend --verbose    cd /Users/adam/Developer/vcs/github.twardoch/pub/vidko
mpy && python -m vidkompy --bg tests/bg.mp4 --fg tests/fg.mp4 -o tests/out-debu
g.mp4 --blend --verbose
02:48:48 | INFO     | __init__ - ✓ Perceptual hashing enabled (pHash)
02:48:48 | INFO     | process - Analyzing videos...
02:48:48 | DEBUG    | get_video_info - Probing video: tests/bg.mp4
02:48:49 | INFO     | get_video_info - Video info for bg.mp4: 1920x1080, 60.00 
fps, 7.85s, 472 frames, audio: yes
02:48:49 | DEBUG    | get_video_info - Probing video: tests/fg.mp4
02:48:49 | INFO     | get_video_info - Video info for fg.mp4: 1920x870, 60.89 f
ps, 8.04s, 483 frames, audio: yes
02:48:49 | INFO     | _log_compatibility - Video compatibility check:
02:48:49 | INFO     | _log_compatibility -   Resolution: 1920x1080 vs 1920x870
02:48:49 | INFO     | _log_compatibility -   FPS: 60.00 vs 60.89
02:48:49 | INFO     | _log_compatibility -   Duration: 7.85s vs 8.04s
02:48:49 | INFO     | _log_compatibility -   Audio: yes vs yes
02:48:49 | INFO     | process - Computing spatial alignment...
02:48:49 | DEBUG    | _template_matching - Using template matching for spatial 
alignment
02:48:49 | INFO     | _template_matching - Template match found at (0, 0) with 
confidence 0.941
02:48:49 | INFO     | process - Spatial alignment result: offset=(0, 0), scale=
1.000, confidence=0.941
02:48:49 | INFO     | process - Computing temporal alignment...
02:48:49 | INFO     | _compute_temporal_alignment - Using border-based temporal
 alignment (border thickness: 8px)
02:48:49 | DEBUG    | create_border_mask - Created border mask: 15360 pixels in
 border region
02:48:49 | INFO     | align_frames_with_mask - Border mode active for temporal 
alignment.
02:48:49 | INFO     | align_frames_with_mask - Border mode with DTW enabled usi
ng masked perceptual hashing.
02:48:49 | DEBUG    | _init_hashers - ✓ PHash initialized
02:48:49 | DEBUG    | _init_hashers - ✓ AverageHash initialized
02:48:49 | DEBUG    | _init_hashers - ✓ ColorMomentHash initialized
02:48:49 | DEBUG    | _init_hashers - ✓ MarrHildrethHash initialized
02:48:49 | INFO     | _init_hashers - Initialized 4 hash algorithms
02:48:49 | INFO     | align_frames_with_mask - Using DTW-based temporal alignme
nt (full frame).
02:48:49 | INFO     | _align_frames_dtw - Using DTW-based temporal alignment
02:48:49 | INFO     | _align_frames_dtw - DTW sampling: 242 FG frames, 472 BG f
rames
02:48:49 | INFO     | _align_frames_dtw - Computing frame fingerprints...
02:48:49 | INFO     | _align_frames_dtw - Using masked fingerprints for border 
mode DTW alignment
02:48:49 | DEBUG    | _precompute_masked_video_fingerprints - Computing masked 
fingerprints for 242 frames
02:49:00 | DEBUG    | _precompute_masked_video_fingerprints - Computed 242 mask
ed fingerprints in 10.41s
02:49:00 | DEBUG    | _precompute_masked_video_fingerprints - Computing masked 
fingerprints for 472 frames
    Extracting 472 frames... ━━━━━━━━━━━━╺━━━━━━━━━━━━━━━━━━━━━━━━━━━ 0:00:55
```

---

I can see from the verbose output that the alignment is finding a spatial offset of (0, 0) which may not be correct. Let me also check the specific test files to understand the expected alignment:

---

```bash
ffprobe tests/bg.mp4 2>&1 | grep -E "(Stream|Duration)" | head -5
```

```
  Duration: 00:00:07.85, start: 0.000000, bitrate: 23676 kb/s
  Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progre
ssive), 1920x1080 [SAR 1:1 DAR 16:9], 23618 kb/s, 60.51 fps, 60 tbr, 15360 tbn
(default)
  Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo,
 fltp, 193 kb/s (default)

```

---

Cancelled

---

_**User**_

time python -m vidkompy --bg tests/bg.mp4 --fg tests/fg.mp4 -o tests/out-c2.mp4 --blend

---

_**Assistant**_



---

_**User**_

02:44:33 | INFO     | ✓ Perceptual hashing enabled (pHash)
02:44:33 | INFO     | Analyzing videos...
02:44:33 | INFO     | Video info for bg.mp4: 1920x1080, 60.00 fps, 7.85s, 472 frames, audio: yes
02:44:34 | INFO     | Video info for fg.mp4: 1920x870, 60.89 fps, 8.04s, 483 frames, audio: yes
02:44:34 | INFO     | Video compatibility check:
02:44:34 | INFO     |   Resolution: 1920x1080 vs 1920x870
02:44:34 | INFO     |   FPS: 60.00 vs 60.89
02:44:34 | INFO     |   Duration: 7.85s vs 8.04s
02:44:34 | INFO     |   Audio: yes vs yes
02:44:34 | INFO     | Computing spatial alignment...
02:44:34 | INFO     | Template match found at (0, 0) with confidence 0.941
02:44:34 | INFO     | Spatial alignment result: offset=(0, 0), scale=1.000, confidence=0.941
02:44:34 | INFO     | Computing temporal alignment...
02:44:34 | INFO     | Using border-based temporal alignment (border thickness: 8px)
02:44:34 | INFO     | Border mode active for temporal alignment.
02:44:34 | INFO     | Border mode with DTW enabled using masked perceptual hashing.
02:44:34 | INFO     | Initialized 4 hash algorithms
02:44:34 | INFO     | Using DTW-based temporal alignment (full frame).
02:44:34 | INFO     | Using DTW-based temporal alignment
02:44:34 | INFO     | DTW sampling: 242 FG frames, 472 BG frames
02:44:34 | INFO     | Computing frame fingerprints...
02:44:34 | INFO     | Using masked fingerprints for border mode DTW alignment
02:46:09 | INFO     | Running DTW alignment...
02:46:09 | INFO     | Starting DTW alignment: 242 fg frames × 472 bg frames, window=100
02:46:10 | INFO     | DTW completed: 242 frame alignments
02:46:10 | INFO     | DTW alignment complete: 483 frames, offset=3.833s, confidence=-4.898
02:46:10 | INFO     | Temporal alignment result: method=dtw, offset=3.833s, frames=483, confidence=-4.898
02:46:10 | INFO     | Composing output video...
02:46:10 | INFO     | Composing video with dtw temporal alignment
02:46:12 | INFO     | Using blend mode with 8px gradient
Composing frames ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 100% (483/483 frames) 0:00:00
02:46:37 | INFO     | Wrote 483 frames to /var/folders/05/clcynl0509ldxltl599hhhx40000gn/T/tmphoadzxwk/temp_silent.mp4
02:46:37 | INFO     | Using foreground audio track
02:46:38 | INFO     | ✅ Processing complete: tests/out-c2.mp4

real	2m5.117s
user	7m35.562s
sys	0m24.674s

---

_**Assistant**_



---

I can see the issue! The spatial alignment is finding the foreground at position (0, 0), but given that the background is 1920x1080 and the foreground is 1920x870, this is clearly wrong. The foreground should be centered vertically, which would place it at approximately (0, 105) to center the 870-pixel-high foreground within the 1080-pixel-high background.

Let me extract sample frames to visualize the problem and then fix the spatial alignment logic:

---

```bash
ffmpeg -i tests/bg.mp4 -vf "select=eq(n\,100)" -vframes 1 tests/bg_frame.png -y
```

```
ffmpeg version 7.1.1 Copyright (c) 2000-2025 the FFmpeg developers
  built with Apple clang version 16.0.0 (clang-1600.0.26.6)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/7.1.1_2 --enable-shared --en
able-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-
ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enab
le-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enabl
e-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-libris
t --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --e
nable-libsvtav1 --enable-libtesseract --enable-libtheora --enable-libvidstab --
enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-lib
x264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-
libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-lib
opencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspee
x --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable
-indev=jack --enable-videotoolbox --enable-audiotoolbox
  libavutil      59. 39.100 / 59. 39.100
  libavcodec     61. 19.101 / 61. 19.101
  libavformat    61.  7.100 / 61.  7.100
  libavdevice    61.  3.100 / 61.  3.100
  libavfilter    10.  4.100 / 10.  4.100
  libswscale      8.  3.100 /  8.  3.100
  libswresample   5.  3.100 /  5.  3.100
  libpostproc    58.  3.100 / 58.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'tests/bg.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf61.7.100
  Duration: 00:00:07.85, start: 0.000000, bitrate: 23676 kb/s
  Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progre
ssive), 1920x1080 [SAR 1:1 DAR 16:9], 23618 kb/s, 60.51 fps, 60 tbr, 15360 tbn
(default)
      Metadata:
        handler_name    : VideoHandler
        vendor_id       : [0][0][0][0]
        encoder         : Lavc61.19.100 h264_nvenc
  Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo,
 fltp, 193 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
        vendor_id       : [0][0][0][0]
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> png (native))
Press [q] to stop, [?] for help
Output #0, image2, to 'tests/bg_frame.png':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf61.7.100
  Stream #0:0(und): Video: png, rgb24(pc, gbr/unknown/unknown, progressive), 19
20x1080 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 60 fps, 60 tbn (default)
      Metadata:
        handler_name    : VideoHandler
        vendor_id       : [0][0][0][0]
        encoder         : Lavc61.19.101 png
frame=    0 fps=0.0 q=0.0 size=       0KiB time=N/A bitrate=N/A dup=100 drop=0 
[image2 @ 0x7fc055304200] The specified filename 'tests/bg_frame.png' does not
contain an image sequence pattern or a pattern is invalid.
[image2 @ 0x7fc055304200] Use a pattern such as %03d for an image sequence or u
se the -update option (with -frames:v 1 if needed) to write a single image.
[out#0/image2 @ 0x7fc055304140] video:2284KiB audio:0KiB subtitle:0KiB other st
reams:0KiB global headers:0KiB muxing overhead: unknown
frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.01 bitrate=N/A dup=100 drop=
0 speed=0.0281x

```

---

_**User**_

NO NO NO, we are spatially perfect but temporally very misaligned. The bg video is very out of sync from the fg. 

---

_**Assistant**_



---

