Slide Scanner Microns Per Pixel Factor Tool

Description

Multiply positive baseMicronsPerPixel by positive downsample for levelMicronsPerPixel, then by nonnegative pixels for lengthMicrons.

Histology images and sections have pixel scales, physical dimensions, cutting indexes, and processing changes. Geometric arithmetic depends on those conventions and does not identify tissue or establish diagnostic adequacy.

Multiply positive baseMicronsPerPixel by positive downsample for levelMicronsPerPixel, then by nonnegative pixels for lengthMicrons.

When to use this tool

Use Slide Scanner Microns Per Pixel Factor when you need one explicit histology image-scale or section-geometry component.

How to use the tool and how it works

Enter baseMicronsPerPixel, downsample, pixels. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read levelMicronsPerPixel, lengthMicrons. Use the output convention below.

Multiply positive baseMicronsPerPixel by positive downsample for levelMicronsPerPixel, then by nonnegative pixels for lengthMicrons.^[1]

Input field	Meaning and units	Accepted input
baseMicronsPerPixel	Base Microns Per Pixel	Required. Finite number; strictly above 0.
downsample	Positive number of base-image pixels per output-level pixel.	Required. Finite number; strictly above 0.
pixels	Pixels	Required. Finite number; minimum 0.

Output field	Interpretation	Returned shape
levelMicronsPerPixel	Level Microns Per Pixel	Required. Finite number.
lengthMicrons	Length Microns	Required. Finite number.

json

{
  "input": {
    "baseMicronsPerPixel": 0.25,
    "downsample": 4,
    "pixels": 200
  },
  "output": {
    "levelMicronsPerPixel": 1,
    "lengthMicrons": 200
  }
}

Limitations and assumptions

Downsample is the ratio of base-image pixels to level pixels; no scanner calibration, image metadata, anisotropy, or actual object measurement is verified.
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

Verify calibration, section preparation, image registration, and the complete sampling protocol before interpreting tissue measurements.

References

Calculation and input contract: histology/slide-scanner-microns-per-pixel-factor — tool.io

Similar or alternative tools

Region Area Pixel Scale
Subtract excludedPixels within nonnegative integer pixelCount and multiply by positive xLengthPerPixel times yLengthPerPixel.
Histology Annotation Physical Area Term
Multiply nonnegative pixelArea by positive xMicronsPerPixel and yMicronsPerPixel for squareMicrons, then divide by one million for squareMillimeters.