Description
Map local image coordinates to a supplied canvas frame.
IIIF-related selectors describe image regions, canvas coordinates and media intervals. A local arithmetic helper can use a restricted syntax or rounding convention while a full IIIF request must satisfy the API and server behavior.
Map local image coordinates to a supplied canvas frame.
When to use this tool
Use IIIF Canvas Coordinate Origin Shift when checking the stated image-region, scaling or media-range convention.
How to use the tool and how it works
- Enter x, y, originX, originY, scale. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read canvasX, canvasY. Use the output convention below.
Map local image coordinates to a supplied canvas frame. Require positive scale; canvasX = originX+x*scale and canvasY similarly.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| x | X | Required. Finite number. |
| y | Y | Required. Finite number. |
| originX | Origin X | Required. Finite number. |
| originY | Origin Y | Required. Finite number. |
| scale | Supplied scale multiplier; units must make the transformed coordinates compatible. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| canvasX | Canvas X | Required. Finite number. |
| canvasY | Canvas Y | Required. Finite number. |
{
"input": {
"x": 10,
"y": 20,
"originX": 100,
"originY": 200,
"scale": 0.5
},
"output": {
"canvasX": 105,
"canvasY": 210
}
}Limitations and assumptions
- This applies translation and uniform scaling only; no manifest, rotation or canvas bounds are validated.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use a conforming IIIF client and actual manifest or image information for complete request validation and resource access.
References
Similar or alternative tools
- IIIF Range One Canvas Duration Term
Return source and playback durations for one canvas range.
- IIIF Region Area Share
Return an in-image rectangle's area fraction.