Subtitling System

STM, the Multilingual Subtitling System

The STM system, a low cost multilingual subtitling system, allows each cable head ends to choose the subtitling language for their region, for instance, spanish, portuguese, english or french. The four language data is sent with the video signal, recovered at the destination where subtitles in the selected language are inserted in the cable customer video signal.

The solution implemented sends eight bytes of information per video frame. A special message packet numbering scheme is used to detect potential data losses. This effectively implements a one way communication channel with the following characteristics:

approx. 240 bytes per second capacity
8 bit CRC error checking
packet numbering for data loss detection
packet repeated on even/odd field

The components of the STM system are:

The STM Editor and the µSTM/P used to produce the multilingual subtitle files.
The STM Encoder and the µSTM/E used for multilingual subtitle encoding
The µSTM used to remotely decode and display the multilingual subtitles.

The STM system is in use by SETTE Ltd since november 97 for TV5 South America and U.S.A. subtitling requirements.

Detailed description (PDF) available soon

Subtitling equipment

The µSTM family

µSTM Multilingual SubTitling System Decoder
µSTM/E Multilingual SubTitling System Encoder
µSTM/P Multilingual SubTitling System Producer
µSTM/GC Multifont Character Generator with VITC reader
reader

The µCC family

µCCI Close Caption Encoder
µCCR Close Caption Reader/Decoder

Subtitling software

ORESME Word + Multimedia based Subtitle Editor
ERNST Environment for the Redaction of News SubTitles
STM Editor Multilingual Subtitle Editor
STM Encoder Multilingual Subtitle Encoder