General Exchange Format Explained

General Exchange Format
Extension:	.gxf
Mime:	application/gxf
Type Code:	"gxf "
Genre:	Container format
Container For:	audiovisual material

General eXchange Format (GXF) is a file exchange format for thetransfer of simple and compound clips between television program storage systems. It is a container format that can contain Motion JPEG (M-JPEG), MPEG, or DV-based video compression standards, with associated audio, time code, and user data that may include user-defined metadata.

GXF was developed by Grass Valley Group, then standardized by SMPTE as SMPTE 360M,^[1] and was extended in SMPTE RDD 14-2007^[2] to include high-definition video resolutions.

GXF has a fairly simple data model compared with SMPTE MXF container format since it should be used for file transfers and not as a storage format with no editing capabilities.^[3] SMPTE RDD 14-2007 is only 57 pages long, compared with many hundreds of pages for the MXF standards.

Applications and tools

Applications

• The FFmpeg multimedia converter and VLC media player free video player support GXF;
• theScribe LITE is a GXF player that also supports MXF.

Parser and checker

• Grassvalley offers a win32-based tool "tstream", for parsing GXF files and checking to ensure the contents conform to spec.

Tools

• GXF::SDK is a C++ [SDK] that implements the GXF standard to ease the reading, creation, sub-clipping, merge and rewrap of GXF files. It supports: MPEG video, DV, PCM, AC3 and Dolby E audio, Timecode, AFD, VBI and ANC;
• GXFDShowFilter is a DirectShow filter that enables Windows MediaPlayer and other DirectShow-based applications to play back GXF files.

Notes and References

1. http://store.smpte.org/product-p/smpte%200360-2009.htm SMPTE 360M
2. http://store.smpte.org/product-p/rdd%2014-2007.htm SMPTE RDD 14-2007
3. http://broadcastengineering.com/mag/broadcasting_file_interchange_formats/ File interchange formats