/* * * Bluetooth low-complexity, subband codec (SBC) library * * Copyright (C) 2004-2009 Marcel Holtmann * Copyright (C) 2004-2005 Henryk Ploetz * Copyright (C) 2005-2006 Brad Midgley * * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #include #include #include #include "sbc.h" #include "sbc_math.h" #include "sbc_tables.h" #include "sbc_primitives.h" #include "sbc_primitives_mmx.h" #include "sbc_primitives_neon.h" /* * A reference C code of analysis filter with SIMD-friendly tables * reordering and code layout. This code can be used to develop platform * specific SIMD optimizations. Also it may be used as some kind of test * for compiler autovectorization capabilities (who knows, if the compiler * is very good at this stuff, hand optimized assembly may be not strictly * needed for some platform). * * Note: It is also possible to make a simple variant of analysis filter, * which needs only a single constants table without taking care about * even/odd cases. This simple variant of filter can be implemented without * input data permutation. The only thing that would be lost is the * possibility to use pairwise SIMD multiplications. But for some simple * CPU cores without SIMD extensions it can be useful. If anybody is * interested in implementing such variant of a filter, sourcecode from * bluez versions 4.26/4.27 can be used as a reference and the history of * the changes in git repository done around that time may be worth checking. */ static inline void sbc_analyze_four_simd(const int16_t *in, int32_t *out, const FIXED_T *consts) { FIXED_A t1[4]; FIXED_T t2[4]; int hop = 0; /* rounding coefficient */ t1[0] = t1[1] = t1[2] = t1[3] = (FIXED_A) 1 << (SBC_PROTO_FIXED4_SCALE - 1); /* low pass polyphase filter */ for (hop = 0; hop < 40; hop += 8) { t1[0] += (FIXED_A) in[hop] * consts[hop]; t1[0] += (FIXED_A) in[hop + 1] * consts[hop + 1]; t1[1] += (FIXED_A) in[hop + 2] * consts[hop + 2]; t1[1] += (FIXED_A) in[hop + 3] * consts[hop + 3]; t1[2] += (FIXED_A) in[hop + 4] * consts[hop + 4]; t1[2] += (FIXED_A) in[hop + 5] * consts[hop + 5]; t1[3] += (FIXED_A) in[hop + 6] * consts[hop + 6]; t1[3] += (FIXED_A) in[hop + 7] * consts[hop + 7]; } /* scaling */ t2[0] = t1[0] >> SBC_PROTO_FIXED4_SCALE; t2[1] = t1[1] >> SBC_PROTO_FIXED4_SCALE; t2[2] = t1[2] >> SBC_PROTO_FIXED4_SCALE; t2[3] = t1[3] >> SBC_PROTO_FIXED4_SCALE; /* do the cos transform */ t1[0] = (FIXED_A) t2[0] * consts[40 + 0]; t1[0] += (FIXED_A) t2[1] * consts[40 + 1]; t1[1] = (FIXED_A) t2[0] * consts[40 + 2]; t1[1] += (FIXED_A) t2[1] * consts[40 + 3]; t1[2] = (FIXED_A) t2[0] * consts[40 + 4]; t1[2] += (FIXED_A) t2[1] * consts[40 + 5]; t1[3] = (FIXED_A) t2[0] * consts[40 + 6]; t1[3] += (FIXED_A) t2[1] * consts[40 + 7]; t1[0] += (FIXED_A) t2[2] * consts[40 + 8]; t1[0] += (FIXED_A) t2[3] * consts[40 + 9]; t1[1] += (FIXED_A) t2[2] * consts[40 + 10]; t1[1] += (FIXED_A) t2[3] * consts[40 + 11]; t1[2] += (FIXED_A) t2[2] * consts[40 + 12]; t1[2] += (FIXED_A) t2[3] * consts[40 + 13]; t1[3] += (FIXED_A) t2[2] * consts[40 + 14]; t1[3] += (FIXED_A) t2[3] * consts[40 + 15]; out[0] = t1[0] >> (SBC_COS_TABLE_FIXED4_SCALE - SCALE_OUT_BITS); out[1] = t1[1] >> (SBC_COS_TABLE_FIXED4_SCALE - SCALE_OUT_BITS); out[2] = t1[2] >> (SBC_COS_TABLE_FIXED4_SCALE - SCALE_OUT_BITS); out[3] = t1[3] >> (SBC_COS_TABLE_FIXED4_SCALE - SCALE_OUT_BITS); } static inline void sbc_analyze_eight_simd(const int16_t *in, int32_t *out, const FIXED_T *consts) { FIXED_A t1[8]; FIXED_T t2[8]; int i, hop; /* rounding coefficient */ t1[0] = t1[1] = t1[2] = t1[3] = t1[4] = t1[5] = t1[6] = t1[7] = (FIXED_A) 1 << (SBC_PROTO_FIXED8_SCALE-1); /* low pass polyphase filter */ for (hop = 0; hop < 80; hop += 16) { t1[0] += (FIXED_A) in[hop] * consts[hop]; t1[0] += (FIXED_A) in[hop + 1] * consts[hop + 1]; t1[1] += (FIXED_A) in[hop + 2] * consts[hop + 2]; t1[1] += (FIXED_A) in[hop + 3] * consts[hop + 3]; t1[2] += (FIXED_A) in[hop + 4] * consts[hop + 4]; t1[2] += (FIXED_A) in[hop + 5] * consts[hop + 5]; t1[3] += (FIXED_A) in[hop + 6] * consts[hop + 6]; t1[3] += (FIXED_A) in[hop + 7] * consts[hop + 7]; t1[4] += (FIXED_A) in[hop + 8] * consts[hop + 8]; t1[4] += (FIXED_A) in[hop + 9] * consts[hop + 9]; t1[5] += (FIXED_A) in[hop + 10] * consts[hop + 10]; t1[5] += (FIXED_A) in[hop + 11] * consts[hop + 11]; t1[6] += (FIXED_A) in[hop + 12] * consts[hop + 12]; t1[6] += (FIXED_A) in[hop + 13] * consts[hop + 13]; t1[7] += (FIXED_A) in[hop + 14] * consts[hop + 14]; t1[7] += (FIXED_A) in[hop + 15] * consts[hop + 15]; } /* scaling */ t2[0] = t1[0] >> SBC_PROTO_FIXED8_SCALE; t2[1] = t1[1] >> SBC_PROTO_FIXED8_SCALE; t2[2] = t1[2] >> SBC_PROTO_FIXED8_SCALE; t2[3] = t1[3] >> SBC_PROTO_FIXED8_SCALE; t2[4] = t1[4] >> SBC_PROTO_FIXED8_SCALE; t2[5] = t1[5] >> SBC_PROTO_FIXED8_SCALE; t2[6] = t1[6] >> SBC_PROTO_FIXED8_SCALE; t2[7] = t1[7] >> SBC_PROTO_FIXED8_SCALE; /* do the cos transform */ t1[0] = t1[1] = t1[2] = t1[3] = t1[4] = t1[5] = t1[6] = t1[7] = 0; for (i = 0; i < 4; i++) { t1[0] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 0]; t1[0] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 1]; t1[1] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 2]; t1[1] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 3]; t1[2] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 4]; t1[2] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 5]; t1[3] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 6]; t1[3] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 7]; t1[4] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 8]; t1[4] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 9]; t1[5] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 10]; t1[5] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 11]; t1[6] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 12]; t1[6] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 13]; t1[7] += (FIXED_A) t2[i * 2 + 0] * consts[80 + i * 16 + 14]; t1[7] += (FIXED_A) t2[i * 2 + 1] * consts[80 + i * 16 + 15]; } for (i = 0; i < 8; i++) out[i] = t1[i] >> (SBC_COS_TABLE_FIXED8_SCALE - SCALE_OUT_BITS); } static inline void sbc_analyze_4b_4s_simd(int16_t *x, int32_t *out, int out_stride) { /* Analyze blocks */ sbc_analyze_four_simd(x + 12, out, analysis_consts_fixed4_simd_odd); out += out_stride; sbc_analyze_four_simd(x + 8, out, analysis_consts_fixed4_simd_even); out += out_stride; sbc_analyze_four_simd(x + 4, out, analysis_consts_fixed4_simd_odd); out += out_stride; sbc_analyze_four_simd(x + 0, out, analysis_consts_fixed4_simd_even); } static inline void sbc_analyze_4b_8s_simd(int16_t *x, int32_t *out, int out_stride) { /* Analyze blocks */ sbc_analyze_eight_simd(x + 24, out, analysis_consts_fixed8_simd_odd); out += out_stride; sbc_analyze_eight_simd(x + 16, out, analysis_consts_fixed8_simd_even); out += out_stride; sbc_analyze_eight_simd(x + 8, out, analysis_consts_fixed8_simd_odd); out += out_stride; sbc_analyze_eight_simd(x + 0, out, analysis_consts_fixed8_simd_even); } static inline int16_t unaligned16_be(const uint8_t *ptr) { return (int16_t) ((ptr[0] << 8) | ptr[1]); } static inline int16_t unaligned16_le(const uint8_t *ptr) { return (int16_t) (ptr[0] | (ptr[1] << 8)); } /* * Internal helper functions for input data processing. In order to get * optimal performance, it is important to have "nsamples", "nchannels" * and "big_endian" arguments used with this inline function as compile * time constants. */ static SBC_ALWAYS_INLINE int sbc_encoder_process_input_s4_internal( int position, const uint8_t *pcm, int16_t X[2][SBC_X_BUFFER_SIZE], int nsamples, int nchannels, int big_endian) { /* handle X buffer wraparound */ if (position < nsamples) { if (nchannels > 0) memcpy(&X[0][SBC_X_BUFFER_SIZE - 36], &X[0][position], 36 * sizeof(int16_t)); if (nchannels > 1) memcpy(&X[1][SBC_X_BUFFER_SIZE - 36], &X[1][position], 36 * sizeof(int16_t)); position = SBC_X_BUFFER_SIZE - 36; } #define PCM(i) (big_endian ? \ unaligned16_be(pcm + (i) * 2) : unaligned16_le(pcm + (i) * 2)) /* copy/permutate audio samples */ while ((nsamples -= 8) >= 0) { position -= 8; if (nchannels > 0) { int16_t *x = &X[0][position]; x[0] = PCM(0 + 7 * nchannels); x[1] = PCM(0 + 3 * nchannels); x[2] = PCM(0 + 6 * nchannels); x[3] = PCM(0 + 4 * nchannels); x[4] = PCM(0 + 0 * nchannels); x[5] = PCM(0 + 2 * nchannels); x[6] = PCM(0 + 1 * nchannels); x[7] = PCM(0 + 5 * nchannels); } if (nchannels > 1) { int16_t *x = &X[1][position]; x[0] = PCM(1 + 7 * nchannels); x[1] = PCM(1 + 3 * nchannels); x[2] = PCM(1 + 6 * nchannels); x[3] = PCM(1 + 4 * nchannels); x[4] = PCM(1 + 0 * nchannels); x[5] = PCM(1 + 2 * nchannels); x[6] = PCM(1 + 1 * nchannels); x[7] = PCM(1 + 5 * nchannels); } pcm += 16 * nchannels; } #undef PCM return position; } static SBC_ALWAYS_INLINE int sbc_encoder_process_input_s8_internal( int position, const uint8_t *pcm, int16_t X[2][SBC_X_BUFFER_SIZE], int nsamples, int nchannels, int big_endian) { /* handle X buffer wraparound */ if (position < nsamples) { if (nchannels > 0) memcpy(&X[0][SBC_X_BUFFER_SIZE - 72], &X[0][position], 72 * sizeof(int16_t)); if (nchannels > 1) memcpy(&X[1][SBC_X_BUFFER_SIZE - 72], &X[1][position], 72 * sizeof(int16_t)); position = SBC_X_BUFFER_SIZE - 72; } #define PCM(i) (big_endian ? \ unaligned16_be(pcm + (i) * 2) : unaligned16_le(pcm + (i) * 2)) /* copy/permutate audio samples */ while ((nsamples -= 16) >= 0) { position -= 16; if (nchannels > 0) { int16_t *x = &X[0][position]; x[0] = PCM(0 + 15 * nchannels); x[1] = PCM(0 + 7 * nchannels); x[2] = PCM(0 + 14 * nchannels); x[3] = PCM(0 + 8 * nchannels); x[4] = PCM(0 + 13 * nchannels); x[5] = PCM(0 + 9 * nchannels); x[6] = PCM(0 + 12 * nchannels); x[7] = PCM(0 + 10 * nchannels); x[8] = PCM(0 + 11 * nchannels); x[9] = PCM(0 + 3 * nchannels); x[10] = PCM(0 + 6 * nchannels); x[11] = PCM(0 + 0 * nchannels); x[12] = PCM(0 + 5 * nchannels); x[13] = PCM(0 + 1 * nchannels); x[14] = PCM(0 + 4 * nchannels); x[15] = PCM(0 + 2 * nchannels); } if (nchannels > 1) { int16_t *x = &X[1][position]; x[0] = PCM(1 + 15 * nchannels); x[1] = PCM(1 + 7 * nchannels); x[2] = PCM(1 + 14 * nchannels); x[3] = PCM(1 + 8 * nchannels); x[4] = PCM(1 + 13 * nchannels); x[5] = PCM(1 + 9 * nchannels); x[6] = PCM(1 + 12 * nchannels); x[7] = PCM(1 + 10 * nchannels); x[8] = PCM(1 + 11 * nchannels); x[9] = PCM(1 + 3 * nchannels); x[10] = PCM(1 + 6 * nchannels); x[11] = PCM(1 + 0 * nchannels); x[12] = PCM(1 + 5 * nchannels); x[13] = PCM(1 + 1 * nchannels); x[14] = PCM(1 + 4 * nchannels); x[15] = PCM(1 + 2 * nchannels); } pcm += 32 * nchannels; } #undef PCM return position; } /* * Input data processing functions. The data is endian converted if needed, * channels are deintrleaved and audio samples are reordered for use in * SIMD-friendly analysis filter function. The results are put into "X" * array, getting appended to the previous data (or it is better to say * prepended, as the buffer is filled from top to bottom). Old data is * discarded when neededed, but availability of (10 * nrof_subbands) * contiguous samples is always guaranteed for the input to the analysis * filter. This is achieved by copying a sufficient part of old data * to the top of the buffer on buffer wraparound. */ static int sbc_enc_process_input_4s_le(int position, const uint8_t *pcm, int16_t X[2][SBC_X_BUFFER_SIZE], int nsamples, int nchannels) { if (nchannels > 1) return sbc_encoder_process_input_s4_internal( position, pcm, X, nsamples, 2, 0); else return sbc_encoder_process_input_s4_internal( position, pcm, X, nsamples, 1, 0); } static int sbc_enc_process_input_4s_be(int position, const uint8_t *pcm, int16_t X[2][SBC_X_BUFFER_SIZE], int nsamples, int nchannels) { if (nchannels > 1) return sbc_encoder_process_input_s4_internal( position, pcm, X, nsamples, 2, 1); else return sbc_encoder_process_input_s4_internal( position, pcm, X, nsamples, 1, 1); } static int sbc_enc_process_input_8s_le(int position, const uint8_t *pcm, int16_t X[2][SBC_X_BUFFER_SIZE], int nsamples, int nchannels) { if (nchannels > 1) return sbc_encoder_process_input_s8_internal( position, pcm, X, nsamples, 2, 0); else return sbc_encoder_process_input_s8_internal( position, pcm, X, nsamples, 1, 0); } static int sbc_enc_process_input_8s_be(int position, const uint8_t *pcm, int16_t X[2][SBC_X_BUFFER_SIZE], int nsamples, int nchannels) { if (nchannels > 1) return sbc_encoder_process_input_s8_internal( position, pcm, X, nsamples, 2, 1); else return sbc_encoder_process_input_s8_internal( position, pcm, X, nsamples, 1, 1); } /* Supplementary function to count the number of leading zeros */ static inline int sbc_clz(uint32_t x) { #ifdef __GNUC__ return __builtin_clz(x); #else /* TODO: this should be replaced with something better if good * performance is wanted when using compilers other than gcc */ int cnt = 0; while (x) { cnt++; x >>= 1; } return 32 - cnt; #endif } static void sbc_calc_scalefactors( int32_t sb_sample_f[16][2][8], uint32_t scale_factor[2][8], int blocks, int channels, int subbands) { int ch, sb, blk; for (ch = 0; ch < channels; ch++) { for (sb = 0; sb < subbands; sb++) { uint32_t x = 1 << SCALE_OUT_BITS; for (blk = 0; blk < blocks; blk++) { int32_t tmp = fabs(sb_sample_f[blk][ch][sb]); if (tmp != 0) x |= tmp - 1; } scale_factor[ch][sb] = (31 - SCALE_OUT_BITS) - sbc_clz(x); } } } /* * Detect CPU features and setup function pointers */ void sbc_init_primitives(struct sbc_encoder_state *state) { /* Default implementation for analyze functions */ state->sbc_analyze_4b_4s = sbc_analyze_4b_4s_simd; state->sbc_analyze_4b_8s = sbc_analyze_4b_8s_simd; /* Default implementation for input reordering / deinterleaving */ state->sbc_enc_process_input_4s_le = sbc_enc_process_input_4s_le; state->sbc_enc_process_input_4s_be = sbc_enc_process_input_4s_be; state->sbc_enc_process_input_8s_le = sbc_enc_process_input_8s_le; state->sbc_enc_process_input_8s_be = sbc_enc_process_input_8s_be; /* Default implementation for scale factors calculation */ state->sbc_calc_scalefactors = sbc_calc_scalefactors; state->implementation_info = "Generic C"; /* X86/AMD64 optimizations */ #ifdef SBC_BUILD_WITH_MMX_SUPPORT sbc_init_primitives_mmx(state); #endif /* ARM optimizations */ #ifdef SBC_BUILD_WITH_NEON_SUPPORT sbc_init_primitives_neon(state); #endif }