Supported formats
Supported formats: every DICOM file, disc and archive Ossidex opens
Ossidex opens standard DICOM files (with or without the .dcm extension), DICOMDIR discs, Enhanced multi-frame CT and MR, and NIfTI volumes, compressed with any common transfer syntax — JPEG 2000, HTJ2K, JPEG Lossless, JPEG-LS, JPEG or RLE. It also unpacks ZIP, RAR, 7z, TAR/GZ and ISO archives, including password-protected ones.
File formats
| Format | Supported | Notes |
|---|---|---|
| DICOM Part 10 (.dcm, .dicom, no extension) | Yes | CT, CBCT, MR, CR/DX/IO/PX X-ray, multi-frame |
| DICOMDIR (disc index) | Yes | Used when valid; the folder is scanned directly when it is incomplete |
| Enhanced multi-frame CT / MR | Yes | Per-frame geometry and calibration kept |
| DICOM without preamble or UIDs | Yes | Recovered where the data allows |
| NIfTI-1 (.nii, .nii.gz) | Yes | Label maps and masks as toggleable layers |
| DICOM SEG, RTSTRUCT, GSPS, SR, Encapsulated PDF | Partly | Kept with the study; display depends on object type |
| JPEG / PDF / HEIF files inside a study folder | Yes | Kept with the study they came with |
| Vendor project files (e.g. Invivo .inv/.apj) | No | Export standard DICOM from the vendor software |
| STL / OBJ surface models | No | Not a mesh viewer |
Compression (transfer syntaxes)
| Codec | Supported |
|---|---|
| Uncompressed, implicit and explicit VR | Yes |
| JPEG Baseline / Extended | Yes |
| JPEG Lossless | Yes |
| JPEG-LS | Yes |
| JPEG 2000 | Yes |
| HTJ2K | Yes |
| RLE Lossless | Yes |
Archives and containers
| Container | Supported | Notes |
|---|---|---|
| ZIP | Yes | Archives inside archives are unpacked too |
| RAR, RAR5, multi-volume RAR | Yes | Select all parts or the folder |
| 7z | Yes | |
| TAR, GZ, TGZ | Yes | |
| ISO / IMG disc images | Yes | |
| Password-protected archives | Yes | Password is asked only for genuinely encrypted archives |
| Self-extracting .exe archives | No | Extract on a computer first |
Modalities
CT, dental CBCT, MRI (including multi-series studies and 4D series split into volumes), X-ray (CR, DX), dental panoramic (PX), intraoral (IO) and cephalometric images. Multi-frame series play as cine in 2D.
If a study does not open, here is what to check — and write to support@ossidex.com: new disc layouts get added regularly.
Format guides
What is a DICOM file? The medical imaging format explained
DICOM is the standard file format for medical images like CT, MRI and X-ray. What is inside a DICOM file, how studies and series work, and how to open one.
DICOMDIR: what it is and how to open it on iPhone, iPad or PC
A DICOMDIR is the index file on a medical imaging disc. Learn what it contains, why it sometimes fails, and how to open the whole disc on iPhone or iPad.
DCM file viewer: what a .dcm file is and how to open it on any device
What a .dcm file is, which DCM viewer to use on Windows, Mac, a browser or iPad, why one file shows one image, and how to convert DCM to JPG safely.
Enhanced multi-frame DICOM (CT and MR) on iPhone and iPad
Enhanced CT and MR store a whole series in one multi-frame DICOM file. How Ossidex reads per-frame geometry, calibration and 4D series on iPhone and iPad.
NIfTI viewer for iPhone and iPad: open .nii and .nii.gz files
Open NIfTI-1 volumes (.nii, .nii.gz) on iPhone and iPad with Ossidex: correct orientation, MPR and 3D, label maps and segmentation masks as layers.
Open DICOM in ZIP, RAR, 7z or ISO archives on iPhone and iPad
Ossidex unpacks DICOM studies from ZIP, RAR (incl. multi-volume), 7z, TAR/GZ and ISO disc images — including password-protected archives — on iPhone and iPad.
Frequently asked questions
Can Ossidex open .dcm files?
Yes — and DICOM files without any extension, which is common on discs.
Can it open a whole CD?
Yes. Copy the disc folder to the device and import the folder; Ossidex reads the DICOMDIR or scans every file.
Does it open JPEG 2000 compressed DICOM?
Yes, including HTJ2K.
Sources
Related pages
Open a DICOM CD on iPhone or iPad
Open a CT, MRI or CBCT disc from a hospital or dental clinic on iPhone or iPad: copy the disc folder, import it in Ossidex, and skip the Windows viewer.
Cloud-link import: providers and limits
Which share links Ossidex imports — Google Drive, Dropbox, OneDrive, iCloud Drive, WeTransfer, Yandex Disk, Mail.ru — how downloads resume, what won’t work.
How Ossidex reads and renders DICOM on iPhone and iPad
How Ossidex decodes DICOM, JPEG 2000 and HTJ2K, rebuilds volumes for MPR and 3D, and renders them with Metal on iPhone and iPad — all on the device.
Study won’t open: fixes
Fixes for DICOM studies that will not open: incomplete downloads, only the viewer copied, proprietary files, password archives, portal links, memory.