Ned Freed wrote:
Thanks, but now I am lost. Why is this a 'video' stream and not a 'text' stream, then?
Presumably because the intent is to display this as video. The rules for what can fit under video are pretty loose; this is certainly an acceptable use of the video top-level type. Text, OTOH, is usually thought of as a series of lines and not as a stream of characters.
My (incorrect) understanding was that video was an unacceptable choice due to SDP constraints. Without that constraint I would have been pushing for this to go under video from the beginning.
You are correct it is not SDP that limits the usage, the question is what the right type is. 3GPP Timed text is clearly text and it is displayed as lines. However it also has connections to video by being specified to placed as an overlay in a specific part of the video display. In addition certain of the modifiers create video-like modifications of the text strings. Especially the karaoke modifier that repaint the characters with a time dependent speed. So it is text, but with a twist. My opinion is that this still is text and many streams will be possible to display on a text only device. You can could in fact make a stock ticker that receives this format. Cheers Magnus Westerlund Multimedia Technologies, Ericsson Research EAB/TVA/A ---------------------------------------------------------------------- Ericsson AB | Phone +46 8 4048287 Torshamsgatan 23 | Fax +46 8 7575550 S-164 80 Stockholm, Sweden | mailto: magnus.westerlund@ericsson.com