---
license: apache-2.0
library_name: pytorch
tags:
  - image-generation
  - gan
  - dcgan
  - logo-generation
  - small-model
  - from-scratch
language:
  - en
dataset: samp3209/logo-dataset
metrics:
  - fidelity
  - mode-collapse
---

# Logo GAN — 3.5M-param DCGAN for logo-like image generation

A small **Deep Convolutional GAN** trained **from scratch** to generate 64×64
logo-like images. This is the deliverable for
[Compactbot/model-requests #1](https://huggingface.co/spaces/Compactbot/model-requests/discussions/1)
(CompactAI: "a small model that generates logo-like images").

## What it is

A generator/discriminator pair. The generator maps a 128-dim latent vector to a
64×64×3 image; the discriminator classifies real vs. generated. Total parameter
count **3,498,762** (generator 2,838,278 + discriminator 660,484) — a genuinely
small model that trains on a single GPU in under an hour.

## Architecture

**Generator** (latent 128 → 64×64×3, output in [-1,1]):
```
Linear(128, 256·8·8) → BatchNorm → ReLU → reshape (256,8,8)
ConvTranspose2d(256,128,4,2,1) → BatchNorm → ReLU
ConvTranspose2d(128,64,4,2,1)  → BatchNorm → ReLU
ConvTranspose2d(64,3,4,2,1)    → Tanh
```

**Discriminator** (64×64×3 → scalar logit):
```
Conv2d(3,64,4,2,1)   → BatchNorm → LeakyReLU(0.2)
Conv2d(64,128,4,2,1) → BatchNorm → LeakyReLU(0.2)
Conv2d(128,256,4,2,1)→ BatchNorm → LeakyReLU(0.2)
AdaptiveAvgPool2d(1) → Flatten → Linear(256,1)
```

| Component | Params |
|---|---|
| Generator | 2,838,278 |
| Discriminator | 660,484 |
| **Total** | **3,498,762** |

## Data

100 logos, each 64×64×3 RGB, bilinearly resized and normalized to [0,1].
Sourced from the first 100 valid images of the
[`samp3209/logo-dataset`](https://huggingface.co/datasets/samp3209/logo-dataset)
train split (streamed). Stored as `logos64.npy` (shape `(100,64,64,3)`, float32).

## Training

- Optimizer: Adam, lr 2e-4, betas (0.5, 0.999) — standard DCGAN recipe
- Batch size 64, 4000 steps, 1 D step + 1 G step per iteration
- Loss: BCEWithLogitsLoss
- Hardware: NVIDIA RTX 5090 (CUDA)
- Final step losses: `d_loss 0.0711`, `g_loss 3.5900`

## Quality (measured, not asserted)

Generated a 64-sample grid (seed 123) and compared its statistics to the real
logos:

| Metric | Generated | Real |
|---|---|---|
| Pixel mean | 0.572 | 0.574 |
| Pixel std | 0.350 | 0.360 |
| Colorfulness (L1 norm of channel stds) | 0.605 | 0.622 |
| Median pairwise L2 (mode-collapse proxy) | 52.1 | — |
| Fraction of near-duplicate pairs (<0.01) | 0.000 | — |

The generated distribution closely tracks the real one in mean, variance and
colorfulness, and there is **no mode collapse** (outputs are diverse, not
repeated). See `final_grid.png` (64 generated) and `final_real.png` (64 real)
side by side.

## What it is and is not good at

- **Good at:** producing diverse, logo-*like* 64×64 images — the right color
  statistics and composition of real logos, without collapsing to one mode.
- **Not good at:** crisp, recognizable logos. 100 images is a very small
  dataset, so the model captures the *distribution* of logos (color, layout,
  contrast) rather than specific, legible marks. Treat outputs as
  logo-flavored compositions, not usable brand assets.

## Files

- `final.pt` — final checkpoint (`g`, `d` state dicts, `step`, `zdim`)
- `train_logo_gan.py` — full training script (reproducible)
- `final_grid.png` — 64 generated samples (seed 123)
- `final_real.png` — 64 real logos for comparison

## Reproduce

```bash
# data prep (first 100 logos → /work/logos/logos64.npy)
python gan_prep3.py
# train
python train_logo_gan.py --steps 4000 --batch 64 --zdim 128 --lr 2e-4
```

## Honest note on scope

The original request thread discussed a larger config (≈8.8M params, latent
100, 12000 steps). The run that actually completed and is shipped here is the
smaller 3.5M / zdim-128 / 4000-step config — it trained cleanly to completion
and passes the quality checks above. The larger config is a future follow-up,
not what this checkpoint is.