DICOM DirectShow Filters

DICOM DirectShow filters need to be registered before they can be used. They do not need to be copied into the system directory, but do need the LEADTOOLS Medical DLLs to work properly.

DICOM DirectShow DLLs

Feature	Filter/Interface(s)	Header	Comments	Help Files
DICOM File Reader	LTDicRd2.DLL DSKernel2.DLL	ILTDicRd2.h	Use the DICOM File Reader to stream the video data in any DICOM file. In addition, it makes it possible for any DirectShow-based media player to play video data in a DICOM file. The filter offers the ability to control the stream speed by changing the frame time. In addition to the basic stream and speed control functionality, the user can insert a user-defined external DICOM dataset and get access to the initialized dataset for use with other processes.	DICOM File Reader Help
DICOM File Writer	LTDicWrt2.DLLDSKernel2.DLL	ILTDicWrt2.h	Use the DICOM File Writer to add video data to a DICOM dataset. The filter has a built-in JPEG and JPEG2000 compressor so it can create JPEG or JPEG2000-compressed DICOM files. It can also be used in conjunction with the LEAD MPEG2 Multiplexer, LEAD MPEG2 Encoder or another MPEG-2 Encoder to create DICOM files with MPEG-2 compression (SD or HD). This filter can be used either as stand-alone or through the LEADTOOLS Medical toolkit. Even when used as stand-alone, the filter still requires redistributables from the Medical Imaging toolkit.	DICOM File Writer Help

DICOM File Reader

Registering the DICOM Reader Filter makes it possible to use any DirectShow-enabled player to automatically play DICOM files. The LEADTOOLS Multimedia toolkit can play DICOM files just like any other video file.

Access the DICOM Reader property page to change the playback rate. The property page can be brought up by the LEADTOOLS Multimedia toolkit using IltmmPlay::HasDialog.

The filter has a built-in JPEG2000 decompressor so it can read JPEG2000-compressed DICOM files. The filter needs the raster LFCMP filter in order to play JPEG-compressed DICOM files.

Some DICOM files are in 16-bit grayscale format. Such files can only be played if the LEAD Video RGB Converter Filter (LMVRGBXF.DLL) or the LEAD Color Space Converter (LMVYUVxf.DLL) is installed (but 8-bit or 24-bit DICOM files can be played without having these conversion filters installed).

Some DICOM files contain:

• MPEG2 Program streams, with MPEG2 Video and MPEG Audio compression. Playing these streams require either the LEAD MPEG Program Demultiplexer or the LEAD MPEG2 Transport Demultiplexer, plus the LEAD MPEG2 Decoder in order to play MPEG2 Program streams (the audio decoder is not necessary because Windows provides one).
• MPEG2 Transport streams with H264 Video and AC3 Audio compression. Playing these require the LEAD MPEG2 Transport Demultiplexer, plus the LEAD H264 Decoder, plus an AC3 audio decoder (LEAD does not provide an AC3 audio decoder).

For more information about the LEAD DICOM Reader Properties page, refer to the ILTDicRd Interface.

DICOM File Writer

DICOM files can contain MPEG2 Transport streams with H264 Video plus AC3 audio compression. To create these, you will need the LEAD MPEG2 Transport Multiplexer, LEAD H264 Encoder, and LEAD AC3 Encoder.

Key Features

Some of the key features for this filter include:

• Ability to create DICOM (SD or HD) files with both video and audio using the MPEG-2 compression. This feature requires using the LEAD MPEG-2 Encoder or another similar MPEG-2 encoder.
• Built-in JPEG compressor to create DICOM files with lossy and/or lossless JPEG compression.
• Built-in JPEG 2000 compressor to create DICOM files with lossy and/or lossless JPEG 2000 compression.
• Ability to add video data to either an existing DICOM file or create a new one from a set of predefined DICOM classes or IODs. Classes differ based on whether MPEG-2 compression is used. The following types of classes are supported by the filter:
• Supported DICOM classes when MPEG-2 compression is used:
• Secondary Capture Multi-Frame True Color Image Storage.
• Video Endoscopic Image Storage.
• Video Photographic Image Storage.
• Video Microscopic Image Storage.
• Supported DICOM classes when MPEG-2 compression is not used:
• Ultrasound Multi-frame Image Storage.
• X-Ray Radiofluoroscopic Image.
• X-Ray Angiographic Image Storage.
• Secondary Capture Multi-frame Grayscale Byte Image Storage.
• Secondary Capture Multi-frame Grayscale Word Image Storage.
• Secondary Capture Multi-Frame True Color Image Storage.
• Unknown Class.
• Can be used as a standalone DirectShow Filter, or programmatically from the LEADTOOLS Medical toolkit.
• Accepts two major DirectShow stream types: Video and stream.
• Accepts the following Video data subtypes:

• Accepts the following Stream data subtypes:

  • MPEG-2 Program

  • MPEG-2 Transport

Required Redistributables for the Medical Imaging Toolkit

DICOM DirectShow filters require the following raster DLLs in order to work properly:

DICOM DirectShow filters DLLs

• LTDICU.DLL
• LTKRNU.DLL
• LTDISU.DLL
• LTIMGCORU.DLL
• LTIMGUTLU.DLL
• LFCMPU.DLL (for playing/creating DICOM files with JPEG compression)

Licensing

The DICOM Filters included with the Multimedia evaluation toolkit are solely for evaluation purposes and may not be copied or distributed. Release versions of the DICOM DirectShow Filters are included with the LEADTOOLS Medical SDK. To obtain pricing and other licensing information for the LEADTOOLS DICOM filters, please contact oemsales@leadtools.com.