> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getlimina.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Processing DCM/DICOM Files

> This guide will get you started with DICOM deidentification.

<Badge color="yellow">Beta</Badge>

Limina supports scanning Digital Imaging and Communications in Medicine (DCM or DICOM) files for PII and creating de-identified or redacted copies. Limina’s supported entity types function across each file type, with localized variants of different **PII** (Personally Identifiable Information) entities, **PHI** (Protected Health Information) entities, and **PCI** (Payment Card Industry) entities being detected. Our [Supported Languages](/languages) and [Supported Entity Types](/entities) page provides a more detailed look.

## How DCM/DICOM Files Are Processed

DICOM files are processed as follows:

1. The DICOM file's contents which include images, metadata and other elements as described in the [DICOM file standard](https://www.dicomstandard.org/) are extracted.
2. Text components of the DICOM file, including supported properties and metadata are processed by Limina's text module, except for the fields listed below in constraints that are assumed to never contain PII. More information about sensitive fields in [DICOM files can be accessed here](https://dicom.nema.org/dicom/2013/output/chtml/part15/chapter_E.html).
3. Any image components of the DICOM file are processed by Limina's [image](/configuration-and-operations/working-with-files/processing-files/image) module. This process finds and masks any sensitive text, such as scan date and operator name. The scan itself, such as an MRI isn't altered.
4. A new DICOM file is constructed using the de-identified or redacted equivalents created in the steps above.

<Info>
  Graphical content where text is present will be OCRed and then redacted. You can configure the OCR System by setting it as an [Environment Variable](/configuration-and-operations/container-management/environment-variables) or sending it in the request object. Check out our [OCR Guide](/configuration-and-operations/working-with-files/processing-files/ocr-modes) to further understand the OCR modes and their usage.
</Info>

## Constraints

* Limina only supports DICOM files with 2D images, DICOM files containing 3D images or videos are not currently supported. Please split 3D images up into a series of 2D images for processing.
* The following metadata and parameters are assumed to never contain PII and are always passed through the output DICOM file:

  ```text Metadata & Parameters theme={"theme":"poimandres"}
  "AcquisitionNumber",
  "BitsAllocated",
  "BitsStored",
  "Columns",
  "ConvolutionKernel",
  "DataCollectionCenter",
  "DataCollectionCenterPatient",
  "DataCollectionDiameter",
  "DetectorBinning",
  "DistanceSourceToDirector",
  "DistanceSourceToPatient",
  "DistanceSourceToDetector",
  "Exposure",
  "ExposureTime",
  "FieldOfViewDimensions",
  "FieldOfViewShape",
  "FieldOfViewOrigin",
  "FilterType",
  "FrameOfReferenceUID",
  "FocalSpots",
  "GantryDetectorTilt",
  "GeneratorPower",
  "Grid",
  "HighBit",
  "ImageOrientationPatient",
  "ImagePositionPatient",
  "ImageType",
  "ImagerPixelSpacing",
  "InstanceCreationDate",
  "InstanceCreationTime",
  "InstanceNumber",
  "IrradiationEventUID",
  "KVP",
  "LargestImagePixelValue",
  "Modality",
  "NumberOfPhaseEncodingSteps",
  "NumberOfStudyRelatedInstances",
  "PhotometricInterpretation",
  "PixelData",
  "PixelPaddingValue",
  "PixelRepresentation",
  "PixelSpacing",
  "PositionReferenceIndicator",
  "ReconstructionDiameter",
  "ReconstructionTargetCenterPatient",
  "RescaleIntercept",
  "RescaleSlope",
  "RotationDirection",
  "Rows",
  "SOPClassUID",
  "SOPInstanceUID",
  "SamplesPerPixel",
  "ScanOptions",
  "SeriesInstanceUID",
  "SeriesNumber",
  "SliceLocation",
  "SliceThickness",
  "SmallestImagePixelValue",
  "SoftwareVersions",
  "SpatialResolution",
  "SpecificCharacterSet",
  "StudyInstanceUID",
  "TableHeight",
  "WindowCenter",
  "WindowWidth",
  "XRayTubeCurrent",
  "XRayTubeCurrentInuA"
  ```

## Support Matrix

|           | CPU Container | GPU Container | Community API | Professional API |
| --------- | ------------- | ------------- | ------------- | ---------------- |
| Supported | Yes           | Yes           | Up to 10 MiB  | No               |

## Sample Request

<Info>
  [Connect with one of our privacy experts](https://getlimina.ai/contact-us/?utm_source=docs\&utm_medium=website) to run this code.
</Info>

<CodeGroup>
  ```json Request Body wrap lines theme={"theme":"poimandres"}
  {
    "file": {
      "data": "<file_content_base64>",
      "content_type": "application/dicom"
    },
    "entity_detection": {
      "return_entity": true
    }
  }
  ```

  ```shell curl wrap lines theme={"theme":"poimandres"}
  echo '{
            "file": {"data": "'$(base64 -w 0 sample.dcm)'", 
            "content_type": "application/dicom"}, 
            "entity_detection": {"return_entity": "True"}
        }' \
  | curl --request POST --url 'https://api.private-ai.com/community/v4/process/files/base64' \
         -H 'Content-Type: application/json' \
         -H 'x-api-key: <YOUR KEY HERE>' \
         -d @- \
         | jq -r .processed_file \
         | base64 -d > 'sample.redacted.dcm'
  ```

  ```python python wrap lines theme={"theme":"poimandres"}
  import requests
  import base64

  file_url = "https://paidocumentation.blob.core.windows.net/$web/sample.dcm"
  filename_out = "/path/to/output/sample.redacted.dcm"
  file_content = requests.get(file_url).content
  file_content_base64 = base64.b64encode(file_content).decode("ascii")

  url = "https://api.private-ai.com/community/v4/process/files/base64"

  headers = {"Content-Type": "application/json", "x-api-key": "<INSERT API KEY>"}

  payload = {
    "file":{
      "data": file_content_base64,
      "content_type": "application/dicom",
    },
    "entity_detection": {
      "return_entity": True
    }
  }

  response = requests.post(url, json=payload, headers=headers)
  with open(filename_out, "wb") as f:
      f.write(base64.b64decode(response.json()["processed_file"]))
  ```

  ```python Python Client wrap lines theme={"theme":"poimandres"}
  from privateai_client import PAIClient
  from privateai_client.objects import request_objects
  import base64

  filename_in = "sample.dcm"
  filename_out = "sample.redacted.dcm"

  file_type= "application/dicom"
  client = PAIClient(url="https://api.private-ai.com/community/v4/", api_key="<YOUR API KEY>")

  with open(filename_in, "rb") as b64_file:
      file_data = base64.b64encode(b64_file.read())
      file_data = file_data.decode("ascii")

  file_obj = request_objects.file_obj(data=file_data, content_type=file_type)
  request_obj = request_objects.file_base64_obj(file=file_obj)
  resp = client.process_files_base64(request_object=request_obj)

  with open(filename_out, 'wb') as redacted_file:
      processed_file = resp.processed_file.encode("ascii")
      processed_file = base64.b64decode(processed_file, validate=True)
      redacted_file.write(processed_file)
  ```
</CodeGroup>

## Sample Response

```json Response wrap lines theme={"theme":"poimandres"}
{
  "processed_file": "Base64 Encoded File Content of the Redacted File",
  "processed_text": "string",
  "entities": "List[Entity]",
  "entities_present": true,
  "languages_detected": {"lang_1": 0.67, "lang_2": 0.74}
}
```