private byte[] GetSubImageBuffer(RunLengthTwoParts twoPartBuffer, NikseBitmap nbmp, Paragraph p, ContentAlignment alignment, Point?overridePosition)
{
var ms = new MemoryStream();
// sup picture data size
WriteEndianWord(twoPartBuffer.Length + 34, ms);
// first display control sequence table address
int startDisplayControlSequenceTableAddress = twoPartBuffer.Length + 4;
WriteEndianWord(startDisplayControlSequenceTableAddress, ms);
// Write image
const int imageTopFieldDataAddress = 4;
ms.Write(twoPartBuffer.Buffer1, 0, twoPartBuffer.Buffer1.Length);
int imageBottomFieldDataAddress = 4 + twoPartBuffer.Buffer1.Length;
ms.Write(twoPartBuffer.Buffer2, 0, twoPartBuffer.Buffer2.Length);
// Write zero delay
ms.WriteByte(0);
ms.WriteByte(0);
// next display control sequence table address (use current is last)
WriteEndianWord(startDisplayControlSequenceTableAddress + 24, ms); // start of display control sequence table address
// Control command start
ms.WriteByte(p.Forced ? (byte)0 : (byte)1);
// Control command 3 = SetColor
WriteColors(ms); // 3 bytes
// Control command 4 = SetContrast
WriteContrast(ms); // 3 bytes
// Control command 5 = SetDisplayArea
WriteDisplayArea(ms, nbmp, alignment, overridePosition); // 7 bytes
// Control command 6 = SetPixelDataAddress
WritePixelDataAddress(ms, imageTopFieldDataAddress, imageBottomFieldDataAddress); // 5 bytes
// Control command exit
ms.WriteByte(255); // 1 byte
// Control Sequence Table
// Write delay - subtitle duration
WriteEndianWord(Convert.ToInt32(p.Duration.TotalMilliseconds * 90.0) >> 10, ms);
// next display control sequence table address (use current is last)
WriteEndianWord(startDisplayControlSequenceTableAddress + 24, ms); // start of display control sequence table address
// Control command 2 = StopDisplay
ms.WriteByte(2);
// extra byte - for compatibility with gpac/MP4BOX
ms.WriteByte(255); // 1 byte
return(ms.ToArray());
}
private byte[] GetSubImageBuffer(RunLengthTwoParts twoPartBuffer, NikseBitmap nbmp, Paragraph p, ContentAlignment alignment)
{
var ms = new MemoryStream();
// sup picture datasize
WriteEndianWord(twoPartBuffer.Length + 34, ms);
// first display control sequence table address
int startDisplayControlSequenceTableAddress = twoPartBuffer.Length + 4;
WriteEndianWord(startDisplayControlSequenceTableAddress, ms);
// Write image
const int imageTopFieldDataAddress = 4;
ms.Write(twoPartBuffer.Buffer1, 0, twoPartBuffer.Buffer1.Length);
int imageBottomFieldDataAddress = 4 + twoPartBuffer.Buffer1.Length;
ms.Write(twoPartBuffer.Buffer2, 0, twoPartBuffer.Buffer2.Length);
// Write zero delay
ms.WriteByte(0);
ms.WriteByte(0);
// next display control sequence table address (use current is last)
WriteEndianWord(startDisplayControlSequenceTableAddress + 24, ms); // start of display control sequence table address
// Control command start
if (p.Forced)
ms.WriteByte(0); // ForcedStartDisplay==0
else
ms.WriteByte(1); // StartDisplay==1
// Control command 3 = SetColor
WriteColors(ms); // 3 bytes
// Control command 4 = SetContrast
WriteContrast(ms); // 3 bytes
// Control command 5 = SetDisplayArea
WriteDisplayArea(ms, nbmp, alignment); // 7 bytes
// Control command 6 = SetPixelDataAddress
WritePixelDataAddress(ms, imageTopFieldDataAddress, imageBottomFieldDataAddress); // 5 bytes
// Control command exit
ms.WriteByte(255); // 1 byte
// Control Sequence Table
// Write delay - subtitle duration
WriteEndianWord(Convert.ToInt32(p.Duration.TotalMilliseconds * 90.0 - 1023) >> 10, ms);
// next display control sequence table address (use current is last)
WriteEndianWord(startDisplayControlSequenceTableAddress + 24, ms); // start of display control sequence table address
// Control command 2 = StopDisplay
ms.WriteByte(2);
// extra byte - for compatability with gpac/MP4BOX
ms.WriteByte(255); // 1 byte
return ms.ToArray();
}
