ATSC Media Files
SignStream plays ATSC 1080i or 720p MPEG-2 Transport Stream files, the same standard digital media file used
by all broadcast TV stations, and is compatible with all ATSC HDTV tuners.
In basic terms, most MPEG-2 videos played on PCs are Program Streams, designed for playback on a device. An
MPEG-2 Transport Stream is similar, but is formatted to maintain signal integrity when sent over long distances.
Encoding ATSC Media Files
Most HDTV video production houses have studio-level software that formats digital media into ATSC streams
required by television broadcasters. Costs for conversion software range from expensive studio programs
(which include features not required for SignStream, such as inserting channel ID information), and low-cost
applications such as MPEG Encoder by MainConcept.
All ATSC files must use the extension
.trp
for playback. The modulator card can play 720p-format media, but
for smooth, seamless transitions in playback, all files should be in 1080i format.
To estimate hard drive storage needs, assume that every 10 GB will host 60 minutes of content.
MainConcept Reference MPEG Transcoder
The MainConcept Reference MPEG Transcoder is not included with SignStream, and is available for $450 from
www.mainconcept.com
, for Windows operating systems. Key features include:
•
Converts AVI, MPEG-2, QuickTime (video), and WMV video files. Graphics and vector based “video”
files, such as Flash, cannot be converted.
•
Encodes 1920 x 1080 (and smaller) digital video files into ATSC 1080i format. This means you can
convert 1280 x 720 and DVD-quality 16:9 (856 x 480) video files for use with SignStream. Generally
speaking, the lower-resolution formats work well for graphic presentations, less for pure video shows.
Ready-made 1080i and 720p presets, and instructions for converting files are available from the SignStream
Content page.
Contemporary Research
4 SignStream Installation and Operation