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-rw-r--r--src/audio_core/codec.cpp77
1 files changed, 0 insertions, 77 deletions
diff --git a/src/audio_core/codec.cpp b/src/audio_core/codec.cpp
deleted file mode 100644
index 868b7a173..000000000
--- a/src/audio_core/codec.cpp
+++ /dev/null
@@ -1,77 +0,0 @@
-// SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-#include <algorithm>
-
-#include "audio_core/codec.h"
-
-namespace AudioCore::Codec {
-
-std::vector<s16> DecodeADPCM(const u8* const data, std::size_t size, const ADPCM_Coeff& coeff,
- ADPCMState& state) {
- // GC-ADPCM with scale factor and variable coefficients.
- // Frames are 8 bytes long containing 14 samples each.
- // Samples are 4 bits (one nibble) long.
-
- constexpr std::size_t FRAME_LEN = 8;
- constexpr std::size_t SAMPLES_PER_FRAME = 14;
- static constexpr std::array<int, 16> SIGNED_NIBBLES{
- 0, 1, 2, 3, 4, 5, 6, 7, -8, -7, -6, -5, -4, -3, -2, -1,
- };
-
- const std::size_t sample_count = (size / FRAME_LEN) * SAMPLES_PER_FRAME;
- const std::size_t ret_size =
- sample_count % 2 == 0 ? sample_count : sample_count + 1; // Ensure multiple of two.
- std::vector<s16> ret(ret_size);
-
- int yn1 = state.yn1, yn2 = state.yn2;
-
- const std::size_t NUM_FRAMES =
- (sample_count + (SAMPLES_PER_FRAME - 1)) / SAMPLES_PER_FRAME; // Round up.
- for (std::size_t framei = 0; framei < NUM_FRAMES; framei++) {
- const int frame_header = data[framei * FRAME_LEN];
- const int scale = 1 << (frame_header & 0xF);
- const int idx = (frame_header >> 4) & 0x7;
-
- // Coefficients are fixed point with 11 bits fractional part.
- const int coef1 = coeff[idx * 2 + 0];
- const int coef2 = coeff[idx * 2 + 1];
-
- // Decodes an audio sample. One nibble produces one sample.
- const auto decode_sample = [&](const int nibble) -> s16 {
- const int xn = nibble * scale;
- // We first transform everything into 11 bit fixed point, perform the second order
- // digital filter, then transform back.
- // 0x400 == 0.5 in 11 bit fixed point.
- // Filter: y[n] = x[n] + 0.5 + c1 * y[n-1] + c2 * y[n-2]
- int val = ((xn << 11) + 0x400 + coef1 * yn1 + coef2 * yn2) >> 11;
- // Clamp to output range.
- val = std::clamp<s32>(val, -32768, 32767);
- // Advance output feedback.
- yn2 = yn1;
- yn1 = val;
- return static_cast<s16>(val);
- };
-
- std::size_t outputi = framei * SAMPLES_PER_FRAME;
- std::size_t datai = framei * FRAME_LEN + 1;
- for (std::size_t i = 0; i < SAMPLES_PER_FRAME && outputi < sample_count; i += 2) {
- const s16 sample1 = decode_sample(SIGNED_NIBBLES[data[datai] >> 4]);
- ret[outputi] = sample1;
- outputi++;
-
- const s16 sample2 = decode_sample(SIGNED_NIBBLES[data[datai] & 0xF]);
- ret[outputi] = sample2;
- outputi++;
-
- datai++;
- }
- }
-
- state.yn1 = static_cast<s16>(yn1);
- state.yn2 = static_cast<s16>(yn2);
-
- return ret;
-}
-
-} // namespace AudioCore::Codec