Google Summer of Code 2018 - Add support for DTMB countries
Add support for DTMB countries
DTMB is the Chinese TV standard, adopted by other countries such as Cuba. We still don't know much about it. Due to this, your proposal must include:
a) A link to the relevant standard documents. We don't know if they exist in English. If they don't but you speak the language they are in, that's fine. If you locate the documents but they require payment (as is often the case for technical specifications) send us a link to buy and we'll allocate organization funds to purchase them.
b) Some TV samples. Or, if you cannot get them directly, an explanation of how you will get them, for example by purchasing a capture card that is known to be compatible (send us an exact link), plugging it to an antenna or dish, etc, that you have access to (detail), etc.
In short, this is an "adventure" task. We'll go all the way with the student that tries it, but we want to make sure the chances of success are reasonable.
This is what we (think we) know so far: DTMB regulates the physical transmission standard (signals, frequencies, etc). It seems to be available (for purchase) here.
The reason Cuba is interesting is that their subtitles will have Latin characters, which will make life a lot easier for most team members. Also, the Cuban government has a good website about their TV regulations.
Apparently the subtitles themselves follow the European DVB standard. We can see that in this document from the Hong Kong regulatory body which says:
Subtitles: Receivers shall include provisions to decode and display subtitles conforming to ETSI EN 300 743.
The Cuban government says the same thing:
That document (in English) says: The Brand and Model TV Set is intended for the reception of DTMB Digital Terrestrial Television in 6MHz bandwidth, according to the specifications GB 20600-2006.
DVB subtitles (ETSI EN 300 743) -- The DUT must support DVB subtitles (ETSI EN 300 743).
Important: Since Chinese is by far the most extended language among DTMB countries, its support is essential. We have some preliminary support for it, but whatever is missing you will need to add. This applies in particular to the .srt writer. Since .srt is text based, you need to OCR the bitmaps. This is already done but almost untested for Chinese. Don't assume it's going to work. Probably not. Give yourself time in your proposal for this.
Related GitHub Issues Extract subtitles in a Chinese newscast
Take a look at this page.