ryujinx/Ryujinx.Graphics.Nvdec.H264/H264BitStreamWriter.cs
gdkchan 4d02a2d2c0
New NVDEC and VIC implementation (#1384)
* Initial NVDEC and VIC implementation

* Update FFmpeg.AutoGen to 4.3.0

* Add nvdec dependencies for Windows

* Unify some VP9 structures

* Rename VP9 structure fields

* Improvements to Video API

* XML docs for Common.Memory

* Remove now unused or redundant overloads from MemoryAccessor

* NVDEC UV surface read/write scalar paths

* Add FIXME comments about hacky things/stuff that will need to be fixed in the future

* Cleaned up VP9 memory allocation

* Remove some debug logs

* Rename some VP9 structs

* Remove unused struct

* No need to compile Ryujinx.Graphics.Host1x with unsafe anymore

* Name AsyncWorkQueue threads to make debugging easier

* Make Vp9PictureInfo a ref struct

* LayoutConverter no longer needs the depth argument (broken by rebase)

* Pooling of VP9 buffers, plus fix a memory leak on VP9

* Really wish VS could rename projects properly...

* Address feedback

* Remove using

* Catch OperationCanceledException

* Add licensing informations

* Add THIRDPARTY.md to release too

Co-authored-by: Thog <me@thog.eu>
2020-07-12 05:07:01 +02:00

121 lines
2.8 KiB
C#

using System;
using System.Numerics;
namespace Ryujinx.Graphics.Nvdec.H264
{
struct H264BitStreamWriter
{
private const int BufferSize = 8;
private readonly byte[] _workBuffer;
private int _offset;
private int _buffer;
private int _bufferPos;
public H264BitStreamWriter(byte[] workBuffer)
{
_workBuffer = workBuffer;
_offset = 0;
_buffer = 0;
_bufferPos = 0;
}
public void WriteBit(bool value)
{
WriteBits(value ? 1 : 0, 1);
}
public void WriteBits(int value, int valueSize)
{
int valuePos = 0;
int remaining = valueSize;
while (remaining > 0)
{
int copySize = remaining;
int free = GetFreeBufferBits();
if (copySize > free)
{
copySize = free;
}
int mask = (1 << copySize) - 1;
int srcShift = (valueSize - valuePos) - copySize;
int dstShift = (BufferSize - _bufferPos) - copySize;
_buffer |= ((value >> srcShift) & mask) << dstShift;
valuePos += copySize;
_bufferPos += copySize;
remaining -= copySize;
}
}
private int GetFreeBufferBits()
{
if (_bufferPos == BufferSize)
{
Flush();
}
return BufferSize - _bufferPos;
}
public void Flush()
{
if (_bufferPos != 0)
{
_workBuffer[_offset++] = (byte)_buffer;
_buffer = 0;
_bufferPos = 0;
}
}
public void End()
{
WriteBit(true);
Flush();
}
public Span<byte> AsSpan()
{
return new Span<byte>(_workBuffer).Slice(0, _offset);
}
public void WriteU(uint value, int valueSize) => WriteBits((int)value, valueSize);
public void WriteSe(int value) => WriteExpGolombCodedInt(value);
public void WriteUe(uint value) => WriteExpGolombCodedUInt(value);
private void WriteExpGolombCodedInt(int value)
{
int sign = value <= 0 ? 0 : 1;
if (value < 0)
{
value = -value;
}
value = (value << 1) - sign;
WriteExpGolombCodedUInt((uint)value);
}
private void WriteExpGolombCodedUInt(uint value)
{
int size = 32 - BitOperations.LeadingZeroCount(value + 1);
WriteBits(1, size);
value -= (1u << (size - 1)) - 1;
WriteBits((int)value, size - 1);
}
}
}