Hi
Searching the forum 1st for an answer to my problem with sub formatting, came across a brief discussion of subs & CC... I thought I might add some additional info in case it helped anyone in the future.
In a nutshell, CC is stored as a separate binary stream in mpg2 video, with timing written to generic or open flags. Because there isn't a standard flag used (like for aspect), you run into problems with decoders --I believe ATSC & DVDs both follow common practice guidelines so not a big problem, but then you get into the ATI, Hauppauge, Microsoft ms formats etc. AFAIK embedding of CC in mpg2 is done during encoding, with an existing CC stream captured along with video, or through hardware to original content. Unfortunately I've encountered problems with DVD players CC display quitting within the 1st half hour or so of video, so for most applications subs on DVD are really an easier & more practical solution.
For those working with captured video for personal use etc., there are several tools/methods for converting CC to subs including SCC Tools. If/when you do have mpg2 that includes a CC stream recognizable by players, it's necessary to turn on CC in a DVDA DVD layout using something like IfoEdit . I can only tell you that ATI captured CC (in mpg2) is not in my experience compatible, but if your captured video is (like perhaps from a DVD recorder), as long as you don't re-encode the mpg2, run it through any Sony Media DVD software & turn on CC display afterwards in the created layout.
Again, just brief, general info: Subs are stored in a DVD layout as a separate, special video stream that only uses 4 colors, and functions as a switchable (on/off) overlay. As you might imagine, can do all sorts of things with this overlay track, limited mostly by available software. A sub track showing text starts out as text of course, then DVDA (or you can use a separate program) render the actual sub/overlay track. There are a fair number of programs available to work with subs, including moving the display in the frame, timing, OCR etc. While the .srt text sub file format is arguably the most popular, there are *Many*, but you can most always find a program to do the conversion into what the software you're using requires.
Just very general info to more or less supplement the old thread I found -- hope it helps someone.
mike
Searching the forum 1st for an answer to my problem with sub formatting, came across a brief discussion of subs & CC... I thought I might add some additional info in case it helped anyone in the future.
In a nutshell, CC is stored as a separate binary stream in mpg2 video, with timing written to generic or open flags. Because there isn't a standard flag used (like for aspect), you run into problems with decoders --I believe ATSC & DVDs both follow common practice guidelines so not a big problem, but then you get into the ATI, Hauppauge, Microsoft ms formats etc. AFAIK embedding of CC in mpg2 is done during encoding, with an existing CC stream captured along with video, or through hardware to original content. Unfortunately I've encountered problems with DVD players CC display quitting within the 1st half hour or so of video, so for most applications subs on DVD are really an easier & more practical solution.
For those working with captured video for personal use etc., there are several tools/methods for converting CC to subs including SCC Tools. If/when you do have mpg2 that includes a CC stream recognizable by players, it's necessary to turn on CC in a DVDA DVD layout using something like IfoEdit . I can only tell you that ATI captured CC (in mpg2) is not in my experience compatible, but if your captured video is (like perhaps from a DVD recorder), as long as you don't re-encode the mpg2, run it through any Sony Media DVD software & turn on CC display afterwards in the created layout.
Again, just brief, general info: Subs are stored in a DVD layout as a separate, special video stream that only uses 4 colors, and functions as a switchable (on/off) overlay. As you might imagine, can do all sorts of things with this overlay track, limited mostly by available software. A sub track showing text starts out as text of course, then DVDA (or you can use a separate program) render the actual sub/overlay track. There are a fair number of programs available to work with subs, including moving the display in the frame, timing, OCR etc. While the .srt text sub file format is arguably the most popular, there are *Many*, but you can most always find a program to do the conversion into what the software you're using requires.
Just very general info to more or less supplement the old thread I found -- hope it helps someone.
mike