SubtitleEdit/libse/SubtitleFormats/AribB24Decoder.cs
2016-07-27 19:24:22 +02:00

193 lines
6.6 KiB
C#

using System.Text;
namespace Nikse.SubtitleEdit.Core.SubtitleFormats
{
/// <summary>
/// ARIB B24 decoding
/// See https://github.com/johnoneil/arib/blob/master/analysis/analysis.txt + https://github.com/johnoneil/arib/blob/master/docs/arib_std_b-24_v5.2-E1_Data_Coding_for_Digital_Broadcast.pdf
/// </summary>
public static class AribB24Decoder
{
private static readonly Encoding EncodingKanji = Encoding.GetEncoding("ISO-2022-JP");
public static string AribToString(byte[] buffer, int index, int length)
{
int end = index + length;
if (end > buffer.Length)
end = buffer.Length;
var sb = new StringBuilder();
int pos = index;
while (pos < end)
{
var b = buffer[pos++];
if (b == 0x09) // Tab (09)
{
sb.Append("\t");
}
else if (b == 0x0d && pos < end && buffer[pos] == 0x0a) // Carriage Return/Line Feed (0D0A)
{
sb.AppendLine();
pos++;
}
else if (b <= 0x1f) // C0
{
ParseC0ControlSet(sb, b, ref pos, buffer);
}
else if (b == 0x20) // SP - Space character
{
sb.Append(" ");
}
else if (b >= 0x21 && b <= 0x7e) // GL - Graphic-set left
{
ParseGlArea(sb, b, ref pos, buffer);
}
else if (b == 0x7f) // DEL - Delete character
{
}
else if (b >= 0x80 && b <= 0x9f) // C1
{
ParseC1ControlSet(sb, b, ref pos, buffer);
}
else if (b >= 0xc0) // GR - Graphic-set right
{
ParseGrArea(sb, b, ref pos, buffer);
}
}
return sb.ToString();
}
private static void ParseC0ControlSet(StringBuilder sb, byte b, ref int pos, byte[] buffer)
{
switch (b)
{
case 0x07: // BEL - Bell
break;
case 0x08: // APB - Active position backward
break;
case 0x09: // APF - Active position forward
break;
case 0x0a: // APD - Active position down
break;
case 0x0b: // APU - Active position up
break;
case 0x0c: // CS - Clear screen
break;
case 0x0d: // APR - Active position return
break;
case 0x0e: // LS1 - Locking shift 1
break;
case 0x0f: // LS0 - Locking shift 0
break;
case 0x16: // PAPF - Parameterized active position forward
break;
case 0x18: // CAN - Cancel
break;
case 0x19: // SS2 - Single shift 2
break;
case 0x1b: // ESC - Escape
break;
case 0x1c: // APS - Active position set
break;
case 0x1d: // SS3 - Single shift 3
break;
case 0x1e: // RS - Record separator
break;
case 0x1f: // US - Unit separator
break;
}
}
private static void ParseC1ControlSet(StringBuilder sb, byte b, ref int pos, byte[] buffer)
{
switch (b)
{
case 0x80: // BKF - Black Foreground
break;
case 0x81: // RDF - Red Foreground
break;
case 0x82: // GRF - Green Foreground
break;
case 0x83: // YLF - Yellow Foreground
break;
case 0x84: // BLF - Blue Foreground
break;
case 0x85: // MGF - Magenta Foreground
break;
case 0x86: // CNF - Cyan Foreground
break;
case 0x87: // WHF - White Foreground
break;
case 0x88: // SSZ - Small Size
break;
case 0x89: // MSZ - Middle Size
break;
case 0x8a: // NSZ - Normal Size
break;
case 0x8b: // SZX - Character Size Controls
b = buffer[pos++];
//SZX 06 / 0 : Tiny size (0x60)
//SZX 04 / 1 : Double height (0x41)
//SZX 04 / 4 : Double width (0x44)
//SZX 04 / 5 : Double height and width (0x45)
//SZX 06 / 11 : Special 1 (0x6b)
//SZX 06 / 4 : Special 2 (0x64)
break;
case 0x90: // = COL - Colour Controls
b = buffer[pos++];
if (b == 0x20)
{
pos++;
}
break;
case 0x91: // LC - Flashing control
break;
case 0x92: // DC - Conceal Display Controls
break;
case 0x93: // OL - Pattern Polarity Controls
break;
case 0x94: // MM - Writing Mode Modification
break;
case 0x95: // MACRO - Macro Command
break;
case 0x97: // HLC - Highlight Character Block
break;
case 0x98: // RPC - Repeat Character
break;
case 0x99: // SPL - Stop Lining
break;
case 0x9a: // STL - Start Lining
break;
case 0x9b: // CSI - Control Sequence Introducer
break;
case 0x9d: // TIME - Time Controls
break;
}
}
private static void ParseGlArea(StringBuilder sb, byte b, ref int pos, byte[] buffer)
{
sb.Append(GetKanjiChar(b, buffer[pos++]));
}
private static void ParseGrArea(StringBuilder sb, byte b, ref int pos, byte[] buffer)
{
sb.Append(GetKanjiChar(b, buffer[pos++]));
}
private static string GetKanjiChar(byte b1, byte b2)
{
return EncodingKanji.GetString(new byte[] { 0x1B, 0x24, 0x40, b1, b2, 0x1B, 0x28, 0x4A });
}
}
}