mirror of
https://github.com/Ryujinx/Ryujinx.git
synced 2024-08-20 15:48:43 +02:00
79 lines
1.7 KiB
C#
79 lines
1.7 KiB
C#
using System.IO;
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namespace Ryujinx.Graphics.VDec
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{
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class H264BitStreamWriter : BitStreamWriter
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{
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public H264BitStreamWriter(Stream baseStream) : base(baseStream) { }
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public void WriteU(int value, int valueSize)
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{
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WriteBits(value, valueSize);
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}
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public void WriteSe(int value)
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{
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WriteExpGolombCodedInt(value);
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}
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public void WriteUe(int value)
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{
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WriteExpGolombCodedUInt((uint)value);
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}
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public void End()
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{
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WriteBit(true);
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Flush();
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}
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private void WriteExpGolombCodedInt(int value)
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{
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int sign = value <= 0 ? 0 : 1;
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if (value < 0)
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{
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value = -value;
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}
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value = (value << 1) - sign;
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WriteExpGolombCodedUInt((uint)value);
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}
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private void WriteExpGolombCodedUInt(uint value)
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{
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int size = 32 - CountLeadingZeros((int)value + 1);
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WriteBits(1, size);
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value -= (1u << (size - 1)) - 1;
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WriteBits((int)value, size - 1);
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}
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private static readonly byte[] ClzNibbleTbl = { 4, 3, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 };
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private static int CountLeadingZeros(int value)
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{
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if (value == 0)
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{
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return 32;
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}
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int nibbleIdx = 32;
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int preCount, count = 0;
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do
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{
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nibbleIdx -= 4;
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preCount = ClzNibbleTbl[(value >> nibbleIdx) & 0b1111];
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count += preCount;
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}
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while (preCount == 4);
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return count;
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}
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}
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} |