Sonic Classic Collection/Technical information
From Sonic Retro
Revision as of 19:15, 25 January 2021 by Ccawley2011 (talk | contribs) (Created page with "{{back}}Category:Technical information {{sub-stub}} '''''TODO:''''' * Move emulation information from the main page * More information about screensGame_eu.dat and Game.p...")
Revision as of 19:15, 25 January 2021 by Ccawley2011 (talk | contribs) (Created page with "{{back}}Category:Technical information {{sub-stub}} '''''TODO:''''' * Move emulation information from the main page * More information about screensGame_eu.dat and Game.p...")
- Back to: Sonic Classic Collection.
|
This teeny-tiny article needs some work. You can help Sonic Retro by expanding it. |
TODO:
- Move emulation information from the main page
- More information about screensGame_eu.dat and Game.pak
- Document any modifications made to the Mega Drive ROMs
- Full list of tracks from the .mods files?
Music and Sound effects
Rather than emulating the Mega Drive audio hardware, all of the music and sound effects are pre-recorded and stored in .mods files. These can be unpacked using this QuickBMS script.
The file format consists of a 32-bit integer containing the number of sound effects or tracks, followed by an array of 32-bit integers, each containing a pointer to a structure containing information about the particular sound. If a pointer is identical to the following pointer, then that pointer is for an empty sound, and should be ignored. The structure uses the following structure:
| Offset | Type | Description |
|---|---|---|
| 0 | 4 Bytes | Length of the sound in bytes, including this header. |
| 4 | 4 Bytes | Number of bytes from the end to be looped. |
| 8 | 2 Bytes | Sample rate. |
| A | 6 Bytes | Unknown. |
The audio data follows immediately after this header, using the IMA ADPCM codec described here.
References
| Sonic Classic Collection | |
|---|---|
|
Manuals |
|
