Datasets:
license: apache-2.0
tags:
- pokemon
- sprites
- pixel-art
- gpt2
- ascii-encoding
pretty_name: GPokeT2 — Pokémon Sprite Dataset
size_categories:
- 10K<n<100K
task_categories:
- text-generation
🎮 GPokeT2 — Pokémon Sprite Dataset
Pokémon sprites from all mainline Gen 3 and Gen 4 games, encoded as ASCII token sequences and paired with rich metadata conditioning labels. Used to train GPokeT2.
| Pokemon sprite | ASCII representation | Train the model | ||
|---|---|---|---|---|
 |
-> |  |
-> | GPT2-Small |
📦 Source data
All sprites were sourced from Veekun, a community sprite repository. Metadata (types, generations, evolution chains) was gathered via PokéAPI.
| Generation | Game | Sprites |
|---|---|---|
| Gen 3 | Pokémon Emerald | 1 600 |
| Gen 3 | Pokémon FireRed / LeafGreen | 312 |
| Gen 3 | Pokémon Ruby / Sapphire | 837 |
| Gen 4 | Pokémon Diamond / Pearl | 2 528 |
| Gen 4 | Pokémon Platinum | 2 556 |
| Gen 4 | Pokémon HeartGold / SoulSilver | 2 560 |
| Total | 10 393 |
🔤 Pixel → ASCII encoding
Each 64×64 sprite is serialized as a flat sequence of ASCII characters. Each pixel is quantized to 4 levels per channel (R, G, B ∈ {0, 1, 2, 3}) and packed into a single character:
char = chr(R×16 + G×4 + B + 59) # 64 possible color chars
char = '~' # white / transparent pixel
This produces a vocabulary of 65 pixel tokens, plus 64 special row-marker tokens ([ROW_00]…[ROW_63]) that delimit each row. A full sprite is therefore a sequence of 64 rows × 64 pixels = 4 096 tokens.
The encoder lives in src/application/slv/pokedex/encoder/pokemon_encoder.py (PokemonEncoder).
🔁 Data augmentation
Each sprite is augmented to produce 12 variants:
| Technique | Factor | Description |
|---|---|---|
| Horizontal flip | ×2 | Pixel order reversed per row at the ASCII level |
| Color shift | ×6 | All 5 non-identity RGB channel permutations + original palette |
Both augmentations are independent and combined: 1 sprite → 2 flip variants × 6 color variants = 12 samples.
Final training set: ~124 700 sequences.
🏷️ Conditioning labels
Each sample carries the following metadata fields:
| Field | Values | Description |
|---|---|---|
type1 |
0–18 | Primary type (18 types + unknown) |
type2 |
0–19 | Secondary type (18 types + none + unknown) |
generation |
0–9 | Game generation (Gen I–IX + margin) |
evo_stage |
0–3 | Basic / Stage 1 / Stage 2 / other |
has_evolution |
0–1 | Whether the Pokémon can still evolve |
is_shiny |
0–1 | Normal vs. shiny palette |
color_shift |
0–5 | Which RGB permutation was applied |
pokemon_idx |
0–N | Unique Pokémon identity index |
Available types (index order):
0 ⬜ normal |
6 🥊 fighting |
12 🔮 psychic |
1 🔥 fire |
7 ☠️ poison |
13 🐛 bug |
2 💧 water |
8 🌍 ground |
14 🪨 rock |
3 ⚡ electric |
9 🌪️ flying |
15 👻 ghost |
4 🌿 grass |
10 🐉 dragon |
16 🌑 dark |
5 🧊 ice |
11 ⚙️ steel |
17 🧚 fairy |
🙏 Acknowledgements
Inspired by matthewRayfield/pokemon-gpt-2.