MGV

MGLV is a video format for MSXgl.

Format

Header

Offset	Size	Desc.	Value
0x0000	3	Signature	"MGV"
0x0003	1	Flag	7 6 5 4 3 2 1 0 │ │ └──┴──┴──┴── File format version (0-15) │ └────────────── Segment size (0: 8 KB, 1: 16 KB) └─────────────────────── Include video format data (4 bytes)
(0x0004)	1	Video format - Image	7 6 5 4 3 2 1 0 │ │ │ └──┴──┴──┴── Screen mode (0-15) │ │ └───────────────── Screen width (0: 256 px, 1: 512 px) └──┴──────────────────── Bit per pixel (0: 1-bit, 1: 2-bit, 2: 4-bit, 3: 8-bit) Screen mode: 0: Text 1 (Screen 0 width 40, 40x27) 1: Graphic 1 (Screen 1, 32x27) 2: Graphic 2 (Screen 2, 32x27) 3: Multi Color (Screen 3, 64x53) 4: Text 2 (Screen 0 width 80, 80x27) 5: Graphic 3 (Screen 4, 32x27) 6: Graphic 4 (Screen 5, 256x212, 16 colors) 7: Graphic 5 (Screen 6, 512x212, 4 colors) 6: Graphic 6 (Screen 7, 512x212, 16 colors) 7: Graphic 7 (Screen 8, 256x212, 256 colors) 8: Graphic 7 + YJK + YAE (Screen 10, 256x212, X colors) 9: Graphic 7 + YJK (Screen 12, 256x212, X colors) 10: Graphic 3 mirrored 0000 (undocumented) 11: Graphic 3 mirrored 0101 (undocumented) 12: Graphic 3 mirrored 0022 (undocumented)
(0x0005)	1	Video format - Replay	7 6 5 4 3 2 1 0 │ │ └──┴──┴──┴── Frame skip (0-15) │ └──────────────────── Loop (0: No, 1: Yes) └─────────────────────── Frequency (0: 50 Hz, 1: 60 Hz) At 50 Hz, a frame skip of 1 means 25 fps. At 60 Hz, a frame skip of 5 means 10 fps.
(0x0006)	1	Video format - Width	1-256 (or 2-512 for Screen mode 6 and 7)
(0x0007)	1	Video format - Height	1-256

Commands

Cmd	Options	Desc.
00		End of data
01		End of segment (increment segment index and reset data pointer)
02		End of line
x3		Switch to table x: 0: Pattern table (default) 1: Color table (screen mode 1, 2 and 3) 2: Layout table (tile based modes)
n4		Skip n bytes (1-15)
05	nn	Skip nn bytes (1-255)
06	nnnn	Skip nnnn bytes (1-65535)
07		Skip a frame / End of frame
n8	vv	Fill n bytes (1-15) with vv value
09	vv,nn	Fill nn bytes (1-255) with vv value
0A	vv,nnnn	Fill nnnn bytes (1-65535) with vv value
0B	vv	Fill a full frame with vv value
nC	vv[n]	Copy n bytes (1-15) from vv[n] data table
0D	nn,vv[nn]	Copy nn bytes (1-255) from vv[nn] data table
0E	nnnn,vv[nnnn]	Copy nnnn bytes (1-65535) from vv[nnnn] data table
0F	vv[]	Copy a full frame from data table (raw frame)

Extension

.MGLV (for Windows/Linux) or .MGV (for MSX-DOS)

Change log

• Version 1.0 (2024/02/12)
  • Original version (File format version 0)