Readout Pixel Size Calculator
Actual readout acquiredpixelmm=encodedFOV/acquired matrix count, not interpolation reconstructed matrix or slice geometry.
Description
Acquired readout pixel size is encoded field of view divided by the acquired readout matrix count.
Acquired readout pixel size is encoded field of view divided by the acquired readout matrix count.1
This tool calculates nominal millimeters per pixel without using an interpolated reconstruction matrix.
When to use Readout Pixel Size Calculator
This tool calculates nominal millimeters per pixel without using an interpolated reconstruction matrix.
How to use Readout Pixel Size Calculator and how it works
- Prepare encoded field of view mm, acquired encoding matrix count, using the input definitions and matching units below.
- Enter the required fields and run Readout Pixel Size Calculator.
- Read result.value using the units, signs and ordering explained below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualEncodedFieldOfViewMm | Actual Encoded Field Of View Mm. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| actualAcquiredEncodingMatrixCount | Actual acquired direction-specific encoding count, not an interpolated reconstruction count. | number | Required; integer 1–1000000; finite; other constraints below |
Require positive encoded field of view in mm and acquired encoding matrix count integer 1–1000000. Divide field of view by acquired count and return nominal pixel mm in the direction named by the tool. The reconstruction/interpolation count is not substituted and other voxel dimensions are not inferred.
pixelMm=encodedFovMm/acquiredEncodingCount Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Geometric side or pixel length in millimeters. | number |
{
"input": {
"actualEncodedFieldOfViewMm": 200,
"actualAcquiredEncodingMatrixCount": 100
},
"output": {
"result": {
"value": 2
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Voxel Volume Calculator for a complementary operation: Rectangular voxel volume combines readout size, phase size and actual slice thickness.
Use Isotropic Voxel Size Calculator for a complementary operation: An equivalent isotropic side length is the cube root of a voxel volume.
References
-
Readout Pixel Size Calculator — tool.io
Similar or alternative tools
- Voxel Volume Calculator
Rectangular voxel volume combines readout size, phase size and actual slice thickness.
- Isotropic Voxel Size Calculator
An equivalent isotropic side length is the cube root of a voxel volume.