Method for reproducing text subtitle and text subtitle decoding system

• US 20050196146A1
• Filed: 10/05/2004
• Published: 09/08/2005
• Est. Priority Date: 02/10/2004
• Status: Abandoned Application

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Yoo, Jea Yong, Kim, Byung Jin, Seo, Kang Soo
• Application Number:
  US10/957,572
• Publication Number:
  US 20050196146A1
• Time in Patent Office: Days
• US Class Current: 386/244
• CPC Class Codes: G11B 2220/2541 Blu-ray discs; Blue laser DVR discs
• CPC Class Codes: G11B 27/10 Indexing; Addressing; Timing or synchronising; Measuring tape travel
• CPC Class Codes: G11B 27/322 used signal is digitally coded
• CPC Class Codes: H04N 9/8233 the additional signal being a character code signal

Abstract

A method for reproducing text subtitle streams and a text subtitle decoding system are disclosed. An entire subtitle text subtitle file designated in a playlist file and font files related to the subtitle text subtitle file are initially preloaded into a subtitle preloading buffer and a font preloading buffer, respectively, before starting playback of the playlist file. Thereafter, the playlist file is played back in order to reproduce at least one audio/video (AV) stream file further designated in the playlist file and the preloaded text subtitle file simultaneously.

Claims

1. A method of reproducing text subtitle streams recorded in an optical disc, the method comprising:

preloading an entire text subtitle file designated in a playlist file in a first buffer at once before starting playback of the playlist file; and

playing back the playlist file in order to reproduce at least one audio/video (AV) stream file designated in the playlist file and the preloaded text subtitle file simultaneously.

2. The method of claim 1, further comprising:

preloading font files related with the text subtitle file in a second buffer before starting the playback of the playlist file.

3. The method of claim 2, wherein information designating the font files is included in a clip information file corresponding to the text subtitle file.

4. The method of claim 2, wherein a size of the second buffer is in the range of 2 to 4 megabytes.

5. The method of claim 2, wherein a size of the second buffer is 4 megabytes when the font files includes at least one of Chinese, Japanese, and Korean (CJK) font files.

6. The method of claim 1, wherein the text subtitle file is recorded in the optical disc and exists as an independent stream file.

7. The method of claim 1, wherein a size of the first buffer is greater than or equal to a size of the text subtitle file.

8. The method of claim 1, wherein a size of the first buffer is greater than or equal to 0.5 megabytes.

9. The method of claim 1, wherein the text subtitle file is designated in a subplayitem included in the playlist file, and the at least one AV stream file is designated in at least one playitem included in the playlist file.

10. A method of reproducing text subtitle streams recorded in an optical disc, the method comprising:

preloading a plurality of text subtitle files in a first buffer at once before starting playback of a playlist file, the plurality of text subtitle files being designated in the playlist for multiple languages application;

playing back the playlist file in order to reproduce at least one audio/video (AV) stream file designated in the playlist file and one of the preloaded text subtitle files simultaneously.

11. The method of claim 10, further comprising:

preloading font files related with the plurality of text subtitle stream files in a second buffer at once before starting the playback of the playlist file.

12. The method of claim 11, wherein a size of the second buffer is greater than or equal to a combined size of the font files.

13. The method of claim 10, wherein a size of the first buffer is greater than or equal to a combined size of the plurality of text subtitle files.

14. A method of reproducing text subtitle streams recorded in an optical disc, the method comprising:

preloading an entire text subtitle file designated in a subplayitem in a first buffer at once before starting playback of a playlist file, the subplayitem being included in the playlist file; and

playing back the playlist file in order to reproduce at least one audio/video (AV) stream file designated in at least one playitem and the preloaded text subtitle file simultaneously, the at least one playitem being included in the playlist file.

15. The method of claim 14, further comprising:

preloading font files related with the text subtitle file in a second buffer before starting the playback of the playlist file.

16. A system for decoding text subtitle streams recorded in an optical disc, the decoding system comprising:

a subtitle preloading buffer configured to preload an entire text subtitle file at once before at least one audio/video (AV) stream file is reproduced, the text subtitle file and the at least one AV stream file being designated in a playlist file; and

a text subtitle decoder configured to decode the text subtitle file preloaded in the subtitle preloading buffer.

17. The decoding system of claim 16, further comprising:

a font preloading buffer configured to preload font files related with the text subtitle file at once before the at least one AV stream file is reproduced.

18. The decoding system of claim 17, wherein information designating the font files is included in a clip information file corresponding to the text subtitle file.

19. The decoding system of claim 17, wherein a size of the font preloading buffer is in the range of 2 to 4 megabytes.

20. The decoding system of claim 16, wherein the text subtitle file is recorded in the optical disc and exist as an independent stream file.

21. The decoding system of claim 16, wherein a size of the subtitle preloading buffer is greater than or equal to a combined size of the text subtitle file.

22. The decoding system of claim 16, wherein the text subtitle file is designated in a subplayitem included in the playlist file, and the at least one AV stream file is designated in at least one playitem included in the playlist file.

23. The decoding system of claim 16, further comprising:

a graphics plane configured to convert an output of the text subtitle decoder into displayable images; and

a color look up table configured to control colors and transparency levels of the displayable images.

24. The decoding system of claim 16, wherein the text subtitle decoder comprises:

a text subtitle processor configured to parse the preloaded text subtitle file into composition and rendering information and dialog text data;

a dialog composition buffer configured to store the composition and rendering information;

a dialog buffer configured to store the dialog text data;

a text renderer configured to render the dialog text data stored in the dialog buffer into a bitmap object according to the composition and rendering information stored in the dialog composition buffer; and

a bitmap object buffer storing the bitmap object.

25. A decoding system for decoding text subtitle streams recorded in an optical disc, the decoding system comprising:

a subtitle preloading buffer configured to preload a plurality of text subtitles files at once before at least one audio/video (AV) stream file designated in a playlist file is reproduced, the plurality of text subtitle files being designated in the playlist file for multiple languages application; and

a text subtitle decoder configured to decode one of the text subtitle files preloaded in the subtitle preloading buffer.

26. The decoding system of claim 25, further comprising:

a font preloading buffer configured to preload font files related with the plurality of text subtitle files at once before the at least one AV stream file is reproduced.

27. The decoding system of claim 26, wherein a size of the font preloading buffer is greater than or equal to a combined size of the font files.

28. The decoding system of claim 26, wherein the text subtitle decoder decodes one of the preloaded text subtitles files using the font files preloaded in the font preloading buffer.

29. The decoding system of claim 25, wherein a size of the subtitle preloading buffer is greater than or equal to a combined size of the plurality of text subtitle files.

30. A disc player for reproducing text subtitle streams recorded in an optical disc, the disc player comprising:

an audio decoding part configured to decode audio streams recorded in the disc;

a video decoding part configured to decode video streams recorded in the disc; and

a subtitle decoding part configured to preload an entire text subtitle file at once before at least one audio/video (AV) stream file is reproduced, and to decode the preloaded text subtitle file, the text subtitle file and the at least one AV stream file being designated in a playlist file.

31. The disc player of claim 30, wherein the subtitle decoding part comprises:

a subtitle preloading buffer configured to preload the entire text subtitle file at once before the at least one AV stream file is reproduced; and

a text subtitle decoder configured to decode the text subtitle file preloaded in the subtitle preloading buffer.

32. The disc player of claim 31, wherein the subtitle decoding part further comprises:

a font preloading buffer configured to preload font files related with the text subtitle file at once before the at least one AV stream file is reproduced.