SCC Subtitle File Format

The SCC file format is used for subtitling as described in the CEA-608 specification for american closed captions standard. The following is important when using the SCC file format:

  • CEA-608 limits the number of characters per row to 32 so that not more than 32 characters per row are allowed in the SCC file format.
  • The only two frame rates that are supported are:
    • 29.97fps drop frame where the character ; is used between seconds and frames
    • 29.97fps non-drop frame where the character : is used between seconds and frames
  • The timecodes define when the following characters will start to be transmitted and only two characters can be transmitted within one video frame
  • Because mostly Pop-On captions are specified in SCC files this means that the last character of the subtitle will contain a special code to display the subtitle

The CEA-608 specification works in a way that two characters (bytes) are transported within one video frame and when all characters are transported a special character is sent to display the complete subtitle. Therefore the IN timecodes visible in the SCC file will not correspond to the IN timecodes visible in the subtitle file in FAB Subtitler. For every two bytes in the SCC file one frame has to be added to the timecode visible in the SCC file.

In CEA-608 the way to delete a subtitle is to send a special character to clear the screen and this character will have the OUT timecode from the subtitle file.

Example of a SCC file:

Scenarist_SCC V1.0

10:00:00;01	9420 9452 9452 97a1 97a1 d375 62f4 e9f4 ece5 2031 2020 ad20 52ef f720 3180 94f2 94f2 97a1 97a1 d375 62f4 e9f4 ece5 2031 2020 ad20 52ef f720 3280 942f

10:00:04;00	942c

10:00:05;03	9420 9452 9452 97a2 97a2 52ef f720 3120 ad20 d375 62f4 e9f4 ece5 2032 94f2 94f2 97a2 97a2 52ef f720 3220 ad20 d375 62f4 e9f4 ece5 2032 942f

10:00:09;00	942c

10:00:10;01	9420 9452 9452 97a1 97a1 d375 62f4 e9f4 ece5 20b3 2020 ad20 52ef f720 3180 94f2 94f2 97a1 97a1 d375 62f4 e9f4 ece5 20b3 2020 ad20 52ef f720 3280 942f

10:00:14;00	942c

10:00:15;03	9420 9452 9452 97a2 97a2 52ef f720 3120 ad20 d375 62f4 e9f4 ece5 2034 94f2 94f2 97a2 97a2 52ef f720 3220 ad20 d375 62f4 e9f4 ece5 2034 942f

10:00:19;00	942c

10:00:20;01	9420 9452 9452 97a1 97a1 d375 62f4 e9f4 ece5 20b5 2020 ad20 52ef f720 3180 94f2 94f2 97a1 97a1 d375 62f4 e9f4 ece5 20b5 2020 ad20 52ef f720 3280 942f

10:00:24;00	942c

Below is the same subtitle file in TTML format:

<?xml version="1.0" encoding="UTF-8"?>
<tt xmlns="http://www.w3.org/ns/ttml" xmlns:tt="http://www.w3.org/ns/ttml" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:ttp="http://www.w3.org/ns/ttml#parameter" xml:lang="et-EE" ttp:timeBase="smpte" ttp:frameRate="30" ttp:frameRateMultiplier="999 1000" ttp:dropMode="dropNTSC">
  <head>
    <styling>
      <style xml:id="normal" tts:color="#FFFFFF" tts:fontWeight="normal" tts:fontStyle="normal" tts:fontFamily="sansSerif" tts:fontSize="100%" />
    </styling>
    <layout>
      <region xml:id="top" tts:origin="0% 0%" tts:extent="100% 15%" tts:textAlign="center" tts:displayAlign="before" />
      <region xml:id="bottom" tts:origin="0% 85%" tts:extent="100% 15%" tts:textAlign="center" tts:displayAlign="after" />
    </layout>
  </head>
  <body style="normal" region="bottom">
    <div>
      <p begin="10:00:01:00" end="10:00:04:00">
        <span>Subtitle 1  - Row 1</span>
        <br />
        <span>Subtitle 1  - Row 2</span>
      </p>
      <p begin="10:00:06:00" end="10:00:09:00">
        <span>Row 1 - Subtitle 2</span>
        <br />
        <span>Row 2 - Subtitle 2</span>
      </p>
      <p begin="10:00:11:00" end="10:00:14:00">
        <span>Subtitle 3  - Row 1</span>
        <br />
        <span>Subtitle 3  - Row 2</span>
      </p>
      <p begin="10:00:16:00" end="10:00:19:00">
        <span>Row 1 - Subtitle 4</span>
        <br />
        <span>Row 2 - Subtitle 4</span>
      </p>
      <p begin="10:00:21:00" end="10:00:24:00">
        <span>Subtitle 5  - Row 1</span>
        <br />
        <span>Subtitle 5  - Row 2</span>
      </p>
    </div>
  </body>
</tt>

This page was last updated on 2022-07-05