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bnnm 2025-01-22 01:46:53 +01:00
parent 2928d402a0
commit e3f714b818
1 changed files with 6 additions and 6 deletions
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12
src/coding/libs/ka1a_dec.c
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@ -15,7 +15,7 @@
* OG code isn't too optimized though. * OG code isn't too optimized though.
* *
* Reverse engineered from exes, thanks to Kelebek1 and AceKombat for help and debugging. * Reverse engineered from exes, thanks to Kelebek1 and AceKombat for help and debugging.
* Output has been compared to memdumps and should be accurate with minor +-diffs. * Output has been compared to memdumps and should be accurate with minor +-diffs (vs MSVC 22 /O2).
* *
* Even though some parts can be simplified/optimized code tries to emulate what source code * Even though some parts can be simplified/optimized code tries to emulate what source code
* may look like, undoing unrolled/vectorized parts. Functions marked as 'inline' don't exist in * may look like, undoing unrolled/vectorized parts. Functions marked as 'inline' don't exist in
@ -147,7 +147,7 @@ static inline int unpack_get_bits(uint8_t* src, int* p_byte_pos, int* p_bit_pos,
// //
// Bands encode less coefs than dst may hold, so 'positions' are used to put coefs // Bands encode less coefs than dst may hold, so 'positions' are used to put coefs
// non-linearly, where unset indexes are 0 (dst must be memset before calling unpack frame). // non-linearly, where unset indexes are 0 (dst must be memset before calling unpack frame).
// dst should be 1024, though usually only lower 512 (max step is 390 + ((1<<7) - 1)). // dst should be 1024, though usually only lower 512 are used (max step is 390 + ((1<<7) - 1)).
static void unpack_frame(uint8_t* src, float* dst, int steps_size, void* unused, int bitrate_index) { static void unpack_frame(uint8_t* src, float* dst, int steps_size, void* unused, int bitrate_index) {
// copy coefs counts as they may be modified below // copy coefs counts as they may be modified below
@ -461,7 +461,7 @@ void transform_frame(void* unused1, float* src, float* dst, void* unused2, float
} }
// Reorder output (input buf may be reused as output here as there is no overlap). // Reorder output (input buf may be reused as output here as there is no overlap).
// Note that input is 512 coefs but output is 1024 samples (externally combined with samples) // Note that input is 512 coefs but output is 1024 samples (externally combined with prev samples)
int pos = 0; int pos = 0;
for (int i = 0; i < 128; i++) { for (int i = 0; i < 128; i++) {
dst[pos++] = real[128 + i]; dst[pos++] = real[128 + i];
@ -522,13 +522,13 @@ static void decode_frame(unsigned char* src, int tracks, int channels, float* ds
} }
} }
if (setup_flag) // MOD: expect only 1 block per call if (setup_flag) // OG MOD: changed to expect only 1 block per call
return; return;
// decode 'current block of frames' (writes 512 samples, plus setups 'prev' buf) // decode 'current block of frames' (writes 512 samples, plus setups 'prev' buf)
{ {
//uint8_t* src_block = &src[channels * tracks * frame_size]; // 2nd block in src in OG code //uint8_t* src_block = &src[channels * tracks * frame_size]; // 2nd block in src in OG code
uint8_t* src_block = &src[0]; // MOD: expect only 1 block per call uint8_t* src_block = &src[0]; // OG MOD: changed to expect only 1 block per call
for (int track = 0; track < tracks; track++) { for (int track = 0; track < tracks; track++) {
int frame_num = channels * track; int frame_num = channels * track;
@ -568,7 +568,7 @@ struct ka1a_handle_t {
// state // state
bool setup_flag; // next frame will be used as setup and won't output samples bool setup_flag; // next frame will be used as setup and won't output samples
float temp[1024 * 2]; // fft + coef buf float temp[1024 * 2]; // fft + spectrum coefs buf
float* prev; // at least samples * channels * tracks float* prev; // at least samples * channels * tracks
}; };