1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
using Ryujinx.Audio.Renderer.Dsp.State;
using Ryujinx.Common.Logging;
using System;
using System.Diagnostics;
using System.Runtime.CompilerServices;
namespace Ryujinx.Audio.Renderer.Dsp
{
public static class AdpcmHelper
{
private const int FixedPointPrecision = 11;
private const int SamplesPerFrame = 14;
private const int NibblesPerFrame = SamplesPerFrame + 2;
private const int BytesPerFrame = 8;
#pragma warning disable IDE0051 // Remove unused private member
private const int BitsPerFrame = BytesPerFrame * 8;
#pragma warning restore IDE0051
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static uint GetAdpcmDataSize(int sampleCount)
{
Debug.Assert(sampleCount >= 0);
int frames = sampleCount / SamplesPerFrame;
int extraSize = 0;
if ((sampleCount % SamplesPerFrame) != 0)
{
extraSize = (sampleCount % SamplesPerFrame) / 2 + 1 + (sampleCount % 2);
}
return (uint)(BytesPerFrame * frames + extraSize);
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int GetAdpcmOffsetFromSampleOffset(int sampleOffset)
{
Debug.Assert(sampleOffset >= 0);
return GetNibblesFromSampleCount(sampleOffset) / 2;
}
public static int NibbleToSample(int nibble)
{
int frames = nibble / NibblesPerFrame;
int extraNibbles = nibble % NibblesPerFrame;
int samples = SamplesPerFrame * frames;
return samples + extraNibbles - 2;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int GetNibblesFromSampleCount(int sampleCount)
{
byte headerSize = 0;
if ((sampleCount % SamplesPerFrame) != 0)
{
headerSize = 2;
}
return sampleCount % SamplesPerFrame + NibblesPerFrame * (sampleCount / SamplesPerFrame) + headerSize;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static short Saturate(int value)
{
if (value > short.MaxValue)
{
value = short.MaxValue;
}
if (value < short.MinValue)
{
value = short.MinValue;
}
return (short)value;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static short GetCoefficientAtIndex(ReadOnlySpan<short> coefficients, int index)
{
if ((uint)index > (uint)coefficients.Length)
{
Logger.Error?.Print(LogClass.AudioRenderer, $"Out of bound read for coefficient at index {index}");
return 0;
}
return coefficients[index];
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int Decode(Span<short> output, ReadOnlySpan<byte> input, int startSampleOffset, int endSampleOffset, int offset, int count, ReadOnlySpan<short> coefficients, ref AdpcmLoopContext loopContext)
{
if (input.IsEmpty || endSampleOffset < startSampleOffset)
{
return 0;
}
byte predScale = (byte)loopContext.PredScale;
byte scale = (byte)(predScale & 0xF);
byte coefficientIndex = (byte)((predScale >> 4) & 0xF);
short history0 = loopContext.History0;
short history1 = loopContext.History1;
short coefficient0 = GetCoefficientAtIndex(coefficients, coefficientIndex * 2 + 0);
short coefficient1 = GetCoefficientAtIndex(coefficients, coefficientIndex * 2 + 1);
int decodedCount = Math.Min(count, endSampleOffset - startSampleOffset - offset);
int nibbles = GetNibblesFromSampleCount(offset + startSampleOffset);
int remaining = decodedCount;
int outputBufferIndex = 0;
int inputIndex = 0;
ReadOnlySpan<byte> targetInput;
targetInput = input[(nibbles / 2)..];
while (remaining > 0)
{
int samplesCount;
if (((uint)nibbles % NibblesPerFrame) == 0)
{
predScale = targetInput[inputIndex++];
scale = (byte)(predScale & 0xF);
coefficientIndex = (byte)((predScale >> 4) & 0xF);
coefficient0 = GetCoefficientAtIndex(coefficients, coefficientIndex * 2);
coefficient1 = GetCoefficientAtIndex(coefficients, coefficientIndex * 2 + 1);
nibbles += 2;
samplesCount = Math.Min(remaining, SamplesPerFrame);
}
else
{
samplesCount = 1;
}
int scaleFixedPoint = FixedPointHelper.ToFixed(1.0f, FixedPointPrecision) << scale;
if (samplesCount < SamplesPerFrame)
{
for (int i = 0; i < samplesCount; i++)
{
int value = targetInput[inputIndex];
int sample;
if ((nibbles & 1) != 0)
{
sample = (value << 28) >> 28;
inputIndex++;
}
else
{
sample = (value << 24) >> 28;
}
nibbles++;
int prediction = coefficient0 * history0 + coefficient1 * history1;
sample = FixedPointHelper.RoundUpAndToInt(sample * scaleFixedPoint + prediction, FixedPointPrecision);
short saturatedSample = Saturate(sample);
history1 = history0;
history0 = saturatedSample;
output[outputBufferIndex++] = saturatedSample;
remaining--;
}
}
else
{
for (int i = 0; i < SamplesPerFrame / 2; i++)
{
int value = targetInput[inputIndex];
int sample0;
int sample1;
sample0 = (value << 24) >> 28;
sample1 = (value << 28) >> 28;
inputIndex++;
int prediction0 = coefficient0 * history0 + coefficient1 * history1;
sample0 = FixedPointHelper.RoundUpAndToInt(sample0 * scaleFixedPoint + prediction0, FixedPointPrecision);
short saturatedSample0 = Saturate(sample0);
int prediction1 = coefficient0 * saturatedSample0 + coefficient1 * history0;
sample1 = FixedPointHelper.RoundUpAndToInt(sample1 * scaleFixedPoint + prediction1, FixedPointPrecision);
short saturatedSample1 = Saturate(sample1);
history1 = saturatedSample0;
history0 = saturatedSample1;
output[outputBufferIndex++] = saturatedSample0;
output[outputBufferIndex++] = saturatedSample1;
}
nibbles += SamplesPerFrame;
remaining -= SamplesPerFrame;
}
}
loopContext.PredScale = predScale;
loopContext.History0 = history0;
loopContext.History1 = history1;
return decodedCount;
}
}
}
|
