How to fix the color problem in the idx / sub file?

How to fix the color problem in the idx / sub file?

Sometimes, even the trick of changing the palette:

palette: 000000, 000000, 000000, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, ffffff, 000000

 in idx file, there are still problem in the subtitle. Using SubResync in VobSub, some of the subtitle, some of subtitle look ugly:




To fix this:

1. With subresync, save the final.idx / final.sub as DVDMaestro format.
   
   　
2. You will see final.son, final.spf (palette) and some bitmaps.
   
   　
3. Open the bitmap file, you will see something like this:
   
   
   Open it with image editor (e.g. GIMP)  it is noted it is a bitmap with 16 color palette.
   But only 4 of color palette entries are used.
   
   　
   
   The 4 colors are: 0x0000ff00 (blue), 0xff000000 (red), 0x00000000 (black) and 0xffffff00 (white)
   
   We are using this color palette for the subtitle. This color palette must be saved in final.spf.
   
   With notepad, save the following to a text file final.spf.xxd:
   
   0000000: 0000 ff00 ff00 0000 0000 0000 ffff ff00 ................
   0000010: ffff ff00 ffff ff00 ffff ff00 ffff ff00 ................
   0000020: ffff ff00 ffff ff00 ffff ff00 ffff ff00 ................
   0000030: ffff ff00 ffff ff00 ffff ff00 ffff ff00 ................
   
   Using xxd (link) to convert it to final.spf.
   
   xxd -r < final.spf.xxd > final.spf
   　
4. Fix the final.son  so that the color palette is fixed.
   　

   st_format 2 Display_Start non_forced TV_Type PAL Tape_Type NON_DROP Pixel_Area (0 573) Directory . Subtitle final Display_Area (0 2 719 575) Contrast (15 15 15 0) SP_NUMBER START END FILE_NAME Color (1 3 0 9) Contrast (4 15 0 15) 0001 00:03:02:12 00:03:05:02 final_0001.bmp Color (12 15 0 9) Contrast (15 15 0 15) 0002 00:03:05:05 00:03:07:08 final_0002.bmp Color (12 2 0 14) 0003 00:03:07:10 00:03:11:08 final_0003.bmp Color (1 3 0 9) Contrast (4 15 0 15) 0004 00:03:11:16 00:03:14:11 final_0004.bmp Color (3 2 0 3) Contrast (15 15 0 15) 0005 00:03:15:05 00:03:17:07 final_0005.bmp Color (9 2 0 15) 0006 00:03:17:10 00:03:21:01 final_0006.bmp Color (1 3 0 9) Contrast (4 15 0 15) 0007 00:03:21:03 00:03:23:03 final_0007.bmp

   
   The lines in red above caused the wrong subtitle used. So modify it to something like:
   　

   st_format 2 Display_Start non_forced TV_Type PAL Tape_Type NON_DROP Pixel_Area (0 573) Directory . Subtitle final-2 Display_Area (0 2 719 575) Contrast (15 15 0 15) Color (1 2 0 3) SP_NUMBER START END FILE_NAME 0001 00:03:02:12 00:03:05:02 final-2_0001.bmp 0002 00:03:05:05 00:03:07:08 final-2_0002.bmp 0003 00:03:07:10 00:03:11:08 final-2_0003.bmp 0004 00:03:11:16 00:03:14:11 final-2_0004.bmp 0005 00:03:15:05 00:03:17:07 final-2_0005.bmp 0006 00:03:17:10 00:03:21:01 final-2_0006.bmp 0007 00:03:21:03 00:03:23:03 final-2_0007.bmp 0008 00:03:23:08 00:03:27:00 final-2_0008.bmp 0009 00:03:27:12 00:03:29:13 final-2_0009.bmp 0010 00:03:29:15 00:03:30:23 final-2_0010.bmp 0011 00:03:37:06 00:03:40:14 final-2_0011.bmp 0012 00:03:40:16 00:03:41:21 final-2_0012.bmp 0013 00:03:44:09 00:03:47:06 final-2_0013.bmp 0014 00:03:47:09 00:03:50:01 final-2_0014.bmp 0015 00:03:50:02 00:03:51:02 final-2_0015.bmp 0016 00:03:51:04 00:03:53:08 final-2_0016.bmp ...

   Note: index 0 is the transparent color.
   
   

5. Download SON2VOBSUB. Open the final.son. Change the height to 576.
   
   
   
   Click Convert.
   　
6. Reopen final.idx with subresync. The subtitle is fixed.