Alien Breed EHF Format
| Format type | Image |
|---|---|
| Hardware | VGA |
| Colour depth | 4-bit |
| Minimum size (pixels) | 320×200 |
| Maximum size (pixels) | 320×200 |
| Palette | External |
| Plane count | 4 |
| Transparent pixels? | Unknown |
| Hitmap pixels? | Unknown |
| Games |
The 15 files include players, aliens, bosses, explosions, and weapons. Every file begins with 00 7D 00 00, the little-endian value 32,000. All 15 decoded with LZHUF to exactly 32,000 bytes and used the compressed stream through the final byte.
File format
A 320×200 four-plane bitmap accounts for the entire payload:
| Decoded offset | Length | Content |
|---|---|---|
| 0x0000 | 8,000 | Plane 0 |
| 0x1F40 | 8,000 | Plane 1 |
| 0x3E80 | 8,000 | Plane 2 |
| 0x5DC0 | 8,000 | Plane 3 |
Each plane has 200 rows of 40 bytes. Bits run from most significant to least significant within each byte. The reconstructed index is:
index(x,y) = sum((((decoded[p*8000 + y*40 + x//8]
>> (7-x%8)) & 1) << p) for p in 0..3)
This interpretation rendered PLAYER1.EHF as a coherent gallery of player animation frames. Using the first 16 colors from decoded PANEL.VHF provided a readable preview; that palette association is a preview choice, not a verified rule of the game.
The compression layer is based on the classic LZHUF source; the plane offsets and visual result are local observations.
Notes
There is no room for an embedded 768-byte palette in this observed 32,000-byte layout. Preserve palette selection as an external dependency. A decoded EHF is not an eight-bit-per-pixel image: reading one byte as one pixel produces the wrong result.
Sprite rectangles, frame order, masks, transparent color, and gameplay palette selection were not established. The planar layout was visually checked on the player sheet; each other sheet's contents have not been individually reviewed.
Files
Paths are relative to game/.
| File | Stored bytes |
|---|---|
| 0BIGBAD.EHF | 4,640 |
| 1BIGBAD.EHF | 5,973 |
| 2BIGBAD.EHF | 7,330 |
| 3BIGBAD.EHF | 7,232 |
| ALIEN00.EHF | 14,644 |
| ALIEN01.EHF | 12,568 |
| ALIEN02.EHF | 13,547 |
| ALIEN03.EHF | 13,066 |
| ALIEN1.EHF | 14,857 |
| BOOM_NEW.EHF | 12,940 |
| DECKMAN1.EHF | 3,427 |
| DECKMAN2.EHF | 3,422 |
| PLAYER1.EHF | 10,575 |
| PLAYER2.EHF | 9,650 |
| WEAPONCL.EHF | 17,435 |
Source code
From re-alienbreed, the open-source browser port and asset viewer:
Credits
The Alien Breed-specific format research and parsers were prepared by VorticonCmdr. If you find this information helpful in a project you're working on, please give credit where credit is due. (A link back to this wiki would be nice too!)