@cornerstonejs/dicom-image-loader
Version:
Cornerstone Image Loader for DICOM WADO-URI and WADO-RS and Local file
48 lines (47 loc) • 2.38 kB
JavaScript
import unpackBinaryFrame from './unpackBinaryFrame';
function getUncompressedImageFrame(dataSet, frameIndex) {
const pixelDataElement = dataSet.elements.x7fe00010 || dataSet.elements.x7fe00008;
const bitsAllocated = dataSet.uint16('x00280100');
const rows = dataSet.uint16('x00280010');
const columns = dataSet.uint16('x00280011');
let samplesPerPixel = dataSet.uint16('x00280002');
const photometricInterpretation = dataSet.string('x00280004');
if (photometricInterpretation === 'YBR_FULL_422') {
samplesPerPixel = 2;
console.warn(`Using SamplesPerPixel of 2 for YBR_FULL_422 photometric interpretation.
See http://dicom.nema.org/medical/dicom/current/output/chtml/part03/sect_C.7.6.3.html for more information.`);
}
const pixelDataOffset = pixelDataElement.dataOffset;
const pixelsPerFrame = rows * columns * samplesPerPixel;
let frameOffset;
if (bitsAllocated === 8) {
frameOffset = pixelDataOffset + frameIndex * pixelsPerFrame;
if (frameOffset >= dataSet.byteArray.length) {
throw new Error('frame exceeds size of pixelData');
}
return new Uint8Array(dataSet.byteArray.buffer.slice(frameOffset, frameOffset + pixelsPerFrame));
}
else if (bitsAllocated === 16) {
frameOffset = pixelDataOffset + frameIndex * pixelsPerFrame * 2;
if (frameOffset >= dataSet.byteArray.length) {
throw new Error('frame exceeds size of pixelData');
}
return new Uint8Array(dataSet.byteArray.buffer.slice(frameOffset, frameOffset + pixelsPerFrame * 2));
}
else if (bitsAllocated === 1) {
frameOffset = pixelDataOffset + frameIndex * pixelsPerFrame * 0.125;
if (frameOffset >= dataSet.byteArray.length) {
throw new Error('frame exceeds size of pixelData');
}
return unpackBinaryFrame(dataSet.byteArray, frameOffset, pixelsPerFrame);
}
else if (bitsAllocated === 32) {
frameOffset = pixelDataOffset + frameIndex * pixelsPerFrame * 4;
if (frameOffset >= dataSet.byteArray.length) {
throw new Error('frame exceeds size of pixelData');
}
return new Uint8Array(dataSet.byteArray.buffer.slice(frameOffset, frameOffset + pixelsPerFrame * 4));
}
throw new Error('unsupported pixel format');
}
export default getUncompressedImageFrame;