LFE_NO_ENTROPY_CODING: added no entropy coding in LFE (47c25bda) · Commits · IVAS Codec Public Collaboration / IVAS Codec

lib_com/options.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -155,9 +155,9 @@
		#define FIX_I68_MC_REVERB_FOR_514 /* Fix HRTF processing for Jot reverb in case of 5.1.4 input format */
		#define FIX_I54_LS_CONVERSION /* FhG: fix incorrect downmix matrix for 5_1_4 to 5_1_2 and upmix matrix for 7_1 to 7_1_4 */
		#define FIX_I25_FBE_FB_BITS /* issue 25: properly skip reading of TBE FB bits when decoder output sampling rate is not 48 kHz */
		#define LFE_NO_ENTROPY_CODING /* issue 65: changes to add no entropy coding in LFE */
		#define ORDER_BITS_ADDITION /* issue 14: Transmit SBA order and planar bits at all bitrates */


		/* ################## End DEVELOPMENT switches ######################### */
		/* clang-format on */
		#endif

lib_dec/ivas_lfe_dec.c

+44 −7

Original line number	Diff line number	Diff line
		@@ -154,6 +154,10 @@ static int16_t ivas_lfe_dec_dequant(
		{
		int16_t shift_bits, i;
		int16_t quant_strategy;
		#ifdef LFE_NO_ENTROPY_CODING
		int16_t coding_strategy;
		int16_t base2_bit_size;
		#endif
		int16_t lfe_bits;
		int16_t all_zeros_dct;
		int16_t min_shift_bits;
		@@ -195,6 +199,23 @@ static int16_t ivas_lfe_dec_dequant(
		sign_bits[i] = get_next_indice( st0, 1 );
		}

		#ifdef LFE_NO_ENTROPY_CODING
		coding_strategy = get_next_indice( st0, 1 );

		if ( coding_strategy )
		{
		for ( iii = 0; iii < num_groups; iii++ )
		{
		base2_bit_size = hLFE->lfe_dec_indices_coeffs_tbl[quant_strategy][iii];
		for ( i = 0; i < 4; i++ )
		{
		abs_values[iii * 4 + i] = get_next_indice( st0, base2_bit_size );
		}
		}
		}
		else
		#endif
		{
		for ( iii = 0; iii < num_groups; iii++ )
		{
		extra_bits_read = 0;
		@@ -206,6 +227,7 @@ static int16_t ivas_lfe_dec_dequant(
		}
		ivas_ari_done_decoding_14bits_ext_1_lfe( st0, extra_bits_read );
		}
		}

		for ( i = 0; i < num_dct_coeffs; i++ )
		{
		@@ -342,6 +364,9 @@ ivas_error ivas_create_lfe_dec(
		const float *filt_coeff;
		LFE_DEC_HANDLE hLFE;
		float lfe_addl_delay_s;
		#ifdef LFE_NO_ENTROPY_CODING
		int16_t i, j;
		#endif

		low_pass_delay_dec_out = 0;
		block_offset_s = 0;
		@@ -441,6 +466,18 @@ ivas_error ivas_create_lfe_dec(
		hLFE->lfe_delay_buf = NULL;
		}

		#ifdef LFE_NO_ENTROPY_CODING
		/* Initialization base2 bits for each subgroup for no entropy coding */
		for ( i = 0; i < IVAS_MAX_NUM_QUANT_STRATS; i++ )
		{
		for ( j = 0; j < IVAS_MAX_NUM_DCT_COEF_GROUPS; j++ )
		{
		hLFE->lfe_dec_indices_coeffs_tbl[i][j] =
		(int16_t) ceilf( log2f( (float) ( ivas_lfe_num_ele_in_coder_models[i][j] + 1 ) ) );
		}
		}
		#endif

		*hLFE_out = hLFE;

		return IVAS_ERR_OK;

lib_dec/ivas_stat_dec.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -1862,6 +1862,9 @@ typedef struct ivas_lfe_dec_data_structure
		ivas_filters_process_state_t filter_state;
		LFE_WINDOW_HANDLE pWindow_state;
		const uint16_t *cum_freq_models[IVAS_MAX_NUM_QUANT_STRATS][IVAS_MAX_NUM_DCT_COEF_GROUPS];
		#ifdef LFE_NO_ENTROPY_CODING
		int16_t lfe_dec_indices_coeffs_tbl[IVAS_MAX_NUM_QUANT_STRATS][IVAS_MAX_NUM_DCT_COEF_GROUPS];
		#endif
		float lfe_block_delay_s;
		int16_t lfe_prior_buf_len;
		float *prior_out_buffer;

lib_enc/ivas_lfe_enc.c

+96 −0

Original line number	Diff line number	Diff line
		@@ -105,6 +105,13 @@ static void ivas_lfe_enc_quant(
		int16_t values[IVAS_LFE_MAX_NUM_DCT_COEFFS << 1];
		float temp_lfe_dct[IVAS_LFE_MAX_NUM_DCT_COEFFS];
		int16_t target_bits;
		#ifdef LFE_NO_ENTROPY_CODING
		int16_t base2_num_bits_tot;
		int16_t coding_strategy;
		int16_t bits_written_arith_enc;
		int16_t next_ind_pos_arith_enc;
		int16_t num_ele_per_grp = IVAS_LFE_NUM_COEFFS_IN_SUBGRP << 1;
		#endif

		target_bits = (int16_t) ( IVAS_LFE_BITRATE_5000 / FRAMES_PER_SEC );

		@@ -127,6 +134,9 @@ static void ivas_lfe_enc_quant(
		uint16_t all_zeros_dct;

		lfe_abs_sum = 0;
		#ifdef LFE_NO_ENTROPY_CODING
		coding_strategy = 0;
		#endif
		num_dct_pass_bins = ivas_lfe_num_dct_pass_bins_tbl[quant_strategy];
		max_of_vals = 0;
		num_groups = num_dct_pass_bins >> 1;
		@@ -236,8 +246,24 @@ static void ivas_lfe_enc_quant(
		push_next_indice( hBstr, write_bit, 1 );
		}

		#ifdef LFE_NO_ENTROPY_CODING
		bits_written_arith_enc = hBstr->nb_bits_tot;
		next_ind_pos_arith_enc = hBstr->next_ind;
		push_next_indice( hBstr, coding_strategy, 1 );
		base2_num_bits_tot = hBstr->nb_bits_tot - bits_written;
		#endif

		ivas_lfe_arith_coding( hLFE, hBstr, quant_strategy, values );

		#ifdef LFE_NO_ENTROPY_CODING
		for ( i = 0; i < num_groups; i++ )
		{
		int16_t base2_num_bits = hLFE->lfe_enc_indices_coeffs_tbl[quant_strategy][i];
		base2_num_bits_tot += ( num_ele_per_grp * base2_num_bits );
		}
		#endif

		#ifndef LFE_NO_ENTROPY_CODING
		if ( ( target_bits + IVAS_LFE_ID_BITS ) >= ( hBstr->nb_bits_tot - bits_written ) )
		{
		break;
		@@ -256,6 +282,61 @@ static void ivas_lfe_enc_quant(
		hBstr->next_ind = next_ind_pos;
		}
		}
		#else
		if ( ( base2_num_bits_tot ) < ( hBstr->nb_bits_tot - bits_written ) )
		{
		if ( quant_strategy == ( num_quant_strategies - 1 ) \|\| ( ( target_bits + IVAS_LFE_ID_BITS ) >= base2_num_bits_tot ) )
		{
		/* reset bits buffer and code the indices with base 2 coding */
		for ( j = hBstr->next_ind - 1; j >= next_ind_pos_arith_enc; j-- )
		{
		hBstr->ind_list[j].nb_bits = -1;
		}
		hBstr->nb_bits_tot = bits_written_arith_enc;
		hBstr->next_ind = next_ind_pos_arith_enc;
		coding_strategy = 1;
		push_next_indice( hBstr, coding_strategy, 1 );

		for ( i = 0; i < num_groups; i++ )
		{
		max_value = ivas_lfe_num_ele_in_coder_models[quant_strategy][i];
		int16_t base2_write_bits = hLFE->lfe_enc_indices_coeffs_tbl[quant_strategy][i];
		int16_t offset = 4 * i;

		for ( j = 0; j < num_ele_per_grp; j++ )
		{
		if ( values[j + offset] > max_value )
		{
		values[j + offset] = max_value;
		}
		push_next_indice( hBstr, values[j + offset], base2_write_bits );
		}
		}
		break;
		}
		}
		else
		{
		if ( ( target_bits + IVAS_LFE_ID_BITS ) >= ( hBstr->nb_bits_tot - bits_written ) )
		{
		break;
		}
		else
		{
		if ( quant_strategy < ( num_quant_strategies - 1 ) )
		{
		/* reset all indices that were already written - TODO: maybe better store them temporarily first and write at the very end? */
		for ( j = hBstr->next_ind - 1; j >= next_ind_pos; j-- )
		{
		hBstr->ind_list[j].nb_bits = -1;
		}

		hBstr->nb_bits_tot = bits_written;
		hBstr->next_ind = next_ind_pos;
		}
		}
		}
		#endif
		}

		/* bits spent for LFE coding */
		@@ -331,6 +412,9 @@ ivas_error ivas_create_lfe_enc(
		int16_t input_frame;
		LFE_ENC_HANDLE hLFE;
		const float *filt_coeff;
		#ifdef LFE_NO_ENTROPY_CODING
		int16_t i, j;
		#endif

		input_frame = (int16_t) ( input_Fs / FRAMES_PER_SEC );

		@@ -392,6 +476,18 @@ ivas_error ivas_create_lfe_enc(
		hLFE->cum_freq_models[1][2] = ivas_str_lfe_freq_models.entropy_coder_model_coarse_sg3;
		hLFE->cum_freq_models[1][3] = &ivas_str_lfe_freq_models.entropy_coder_model_coarse_sg4;

		#ifdef LFE_NO_ENTROPY_CODING
		/* Initialization base2 bits for each subgroup for no entropy coding */
		for ( i = 0; i < IVAS_MAX_NUM_QUANT_STRATS; i++ )
		{
		for ( j = 0; j < IVAS_MAX_NUM_DCT_COEF_GROUPS; j++ )
		{
		hLFE->lfe_enc_indices_coeffs_tbl[i][j] =
		(int16_t) ceilf( log2f( (float) ( ivas_lfe_num_ele_in_coder_models[i][j] + 1 ) ) );
		}
		}
		#endif

		*hLFE_out = hLFE;

		return IVAS_ERR_OK;

lib_enc/ivas_stat_enc.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -971,6 +971,9 @@ typedef struct ivas_lfe_enc_data_structure
		LFE_WINDOW_HANDLE pWindow_state;
		BSTR_ENC_HANDLE hBstr; /* pointer to encoder bitstream handle */
		const uint16_t *cum_freq_models[IVAS_MAX_NUM_QUANT_STRATS][IVAS_MAX_NUM_DCT_COEF_GROUPS];
		#ifdef LFE_NO_ENTROPY_CODING
		int16_t lfe_enc_indices_coeffs_tbl[IVAS_MAX_NUM_QUANT_STRATS][IVAS_MAX_NUM_DCT_COEF_GROUPS];
		#endif
		int16_t lfe_bits;
		float *old_wtda_audio;