Description
Return maximum centered aspect-compatible crop dimensions and retained area.
Artwork measurements distinguish physical dimensions, projected regions and scale conventions. Length, area and volume change with different powers of a scale, while frame overlaps and crop geometry depend on which boundaries were measured. A numerical fit does not identify an artwork or establish its historical interpretation.
Return maximum centered aspect-compatible crop dimensions and retained area.
When to use this tool
Use Painting Canvas Aspect Reframing Gap when checking the stated artwork dimension, crop, frame or scale relation.
How to use the tool and how it works
- Enter width, height, targetRatio. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read currentRatio, cropWidth, cropHeight, retainedAreaFraction. Use the output convention below.
Return maximum centered aspect-compatible crop dimensions and retained area. Require width/height/targetRatio > 0; cropWidth = min(width,height*ratio), cropHeight = min(height,width/ratio), retained fraction divides crop area by original.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| width | Width | Required. Finite number; strictly above 0. |
| height | Height | Required. Finite number; strictly above 0. |
| targetRatio | Target Ratio | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| currentRatio | Current Ratio | Required. Finite number. |
| cropWidth | Crop Width | Required. Finite number. |
| cropHeight | Crop Height | Required. Finite number. |
| retainedAreaFraction | Ideal centered crop area divided by original area; does not crop an image. | Required. Finite number. |
{
"input": {
"width": 60,
"height": 40,
"targetRatio": 1
},
"output": {
"currentRatio": 1.5,
"cropWidth": 40,
"cropHeight": 40,
"retainedAreaFraction": 0.6666666666666666
}
}Limitations and assumptions
- This assumes axis-aligned cropping without rotation; composition, object identity and appropriate reframing are not evaluated.
- 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
Inspect the original object, measured boundaries and appropriate complete geometry or catalog record for physical or historical conclusions.
References
Similar or alternative tools
- Painted Panel Join Width Fraction
Return panel join-width total and share.
- Mural Register Height Proportion
Return mural register-height fraction and target-height gap.