JPEG_Info (changes)
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Programmer's SpriteExtend Reference Manuals
» Part 11 – Sound and Video?SWI Calls
» JPEG_InfoJPEG?
» JPEG SWI Calls
» JPEG_Info
JPEG_Info
(SWI &49980)
| Entry | |
|---|---|
| R0 | Flags: |
| Bit 0: Return dimensions | |
| Bit 1: Return SOF type | |
| Other bits reserved, should be zero | |
| R1 | Pointer to JPEG image in memory |
| R2 | Length of data (bytes) |
| Exit | |
|---|---|
| R0 | Flags: |
| Bit 0: Image is greyscale | |
| Bit 1: Transformed plots are not supported | |
| Bit 2: Pixel density is only a ratio | |
| Bits 3-6: SOF type (if requested) | |
| R2 | Width in pixels |
| R3 | Height in pixels |
| R4 | X pixel density |
| R5 | Y pixel density |
| R6 | Size of extra workspace needed to render |
| - | Other registers preserved |
Use
This call is used to read the attributes of a JPEG image held in memory.
See also
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