/// <summary>
/// parse an PDS packet which contain palette info
/// </summary>
/// <param name="buffer">Buffer of raw byte data, starting right after segment</param>
/// <param name="segment">object containing info about the current segment</param>
/// <param name="pic">SubPicture object containing info about the current caption</param>
/// <param name="msg">reference to message string</param>
/// <returns>number of valid palette entries (-1 for fault)</returns>
private static int ParsePds(byte[] buffer, SupSegment segment, BluRaySupPicture pic, string[] msg)
{
int paletteId = buffer[0]; // 8bit palette ID (0..7)
// 8bit palette version number (incremented for each palette change)
int paletteUpdate = buffer[1];
if (pic.Palettes == null)
{
pic.Palettes = new List <List <PaletteInfo> >();
for (int i = 0; i < 8; i++)
{
pic.Palettes.Add(new List <PaletteInfo>());
}
}
if (paletteId > 7)
{
msg[0] = "Illegal palette id at offset " + ToolBox.ToHex(buffer, 0, 8);
return(-1);
}
List <PaletteInfo> al = pic.Palettes[paletteId];
if (al == null)
{
al = new List <PaletteInfo>();
}
PaletteInfo p = new PaletteInfo();
p.PaletteSize = (segment.Size - 2) / 5;
p.PaletteBuffer = new byte[p.PaletteSize * 5];
Buffer.BlockCopy(buffer, 2, p.PaletteBuffer, 0, p.PaletteSize * 5); // save palette buffer in palette object
al.Add(p);
msg[0] = "ID: " + paletteId + ", update: " + paletteUpdate + ", " + p.PaletteSize + " entries";
return(p.PaletteSize);
}
public PaletteInfo(PaletteInfo paletteInfo)
{
PaletteSize = paletteInfo.PaletteSize;
PaletteBuffer = new byte[paletteInfo.PaletteBuffer.Length];
Buffer.BlockCopy(paletteInfo.PaletteBuffer, 0, PaletteBuffer, 0, PaletteBuffer.Length);
}
/// <summary>
/// decode palette from the input stream
/// </summary>
/// <param name="pic">SubPicture object containing info about the current caption</param>
/// <returns>Palette object</returns>
public BluRaySupPalette DecodePalette(BluRaySupPalette defaultPalette)
{
BluRaySupPicture pic = this;
bool fadeOut = false;
if (pic.Palettes.Count == 0 || pic.ObjectIdImage.PaletteId >= pic.Palettes.Count)
{
System.Diagnostics.Debug.Print("Palette not found in objectID=" + pic.ObjectId + " PaletteId=" + pic.ObjectIdImage.PaletteId + "!");
if (defaultPalette == null)
{
return(new BluRaySupPalette(256, Core.UsesBt601()));
}
else
{
return(new BluRaySupPalette(defaultPalette));
}
}
List <PaletteInfo> pl = pic.Palettes[pic.ObjectIdImage.PaletteId];
BluRaySupPalette palette = new BluRaySupPalette(256, Core.UsesBt601());
// by definition, index 0xff is always completely transparent
// also all entries must be fully transparent after initialization
for (int j = 0; j < pl.Count; j++)
{
PaletteInfo p = pl[j];
int index = 0;
for (int i = 0; i < p.PaletteSize; i++)
{
// each palette entry consists of 5 bytes
int palIndex = p.PaletteBuffer[index];
int y = p.PaletteBuffer[++index];
int cr, cb;
if (Core.GetSwapCrCb())
{
cb = p.PaletteBuffer[++index];
cr = p.PaletteBuffer[++index];
}
else
{
cr = p.PaletteBuffer[++index];
cb = p.PaletteBuffer[++index];
}
int alpha = p.PaletteBuffer[++index];
int alphaOld = palette.GetAlpha(palIndex);
// avoid fading out
if (alpha >= alphaOld || alpha == 0)
{
if (alpha < Core.GetAlphaCrop())
{// to not mess with scaling algorithms, make transparent color black
y = 16;
cr = 128;
cb = 128;
}
palette.SetAlpha(palIndex, alpha);
}
else
{
fadeOut = true;
}
palette.SetYCbCr(palIndex, y, cb, cr);
index++;
}
}
if (fadeOut)
{
System.Diagnostics.Debug.Print("fade out detected -> patched palette\n");
}
return(palette);
}