X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=wmadec_filter.c;h=49f69b54d7601168ef195c938ae800a229f5ba19;hp=d574df35d3a9da3a75f25bf0069f6e887b8b547e;hb=3010ef96e10cb15d423eef8f9802fbed78744393;hpb=2d58aec6b7de7fdad67518568a79632b1944ee90

diff --git a/wmadec_filter.c b/wmadec_filter.c
index d574df35..49f69b54 100644
--- a/wmadec_filter.c
+++ b/wmadec_filter.c
@@ -25,6 +25,7 @@
 #include <string.h>
 #include <regex.h>
 #include <sys/select.h>
+#include <stdbool.h>
 
 #include "para.h"
 #include "error.h"
@@ -32,6 +33,7 @@
 #include "ggo.h"
 #include "string.h"
 #include "sched.h"
+#include "buffer_tree.h"
 #include "filter.h"
 #include "bitstream.h"
 #include "imdct.h"
@@ -59,19 +61,25 @@
 #define LSP_POW_BITS 7
 
 struct private_wmadec_data {
+	/** Information contained in the audio file header. */
 	struct asf_header_info ahi;
 	struct getbit_context gb;
+	/** Whether to use the bit reservoir. */
 	int use_bit_reservoir;
+	/** Whether to use variable block length. */
 	int use_variable_block_len;
-	int use_exp_vlc;	///< exponent coding: 0 = lsp, 1 = vlc + delta
-	int use_noise_coding;	///< true if perceptual noise is added
+	/** Whether to use exponent coding. */
+	int use_exp_vlc;
+	/** Whether perceptual noise is added. */
+	int use_noise_coding;
 	int byte_offset_bits;
 	struct vlc exp_vlc;
 	int exponent_sizes[BLOCK_NB_SIZES];
 	uint16_t exponent_bands[BLOCK_NB_SIZES][25];
-	int high_band_start[BLOCK_NB_SIZES];	///< index of first coef in high band
-	int coefs_start;	///< first coded coef
-	int coefs_end[BLOCK_NB_SIZES];	///< max number of coded coefficients
+	/** The index of the first coef in high band. */
+	int high_band_start[BLOCK_NB_SIZES];
+	/** Maximal number of coded coefficients. */
+	int coefs_end[BLOCK_NB_SIZES];
 	int exponent_high_sizes[BLOCK_NB_SIZES];
 	int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
 	struct vlc hgain_vlc;
@@ -85,20 +93,31 @@ struct private_wmadec_data {
 	uint16_t *run_table[2];
 	uint16_t *level_table[2];
 	const struct coef_vlc_table *coef_vlcs[2];
-	/* frame info */
-	int frame_len;		///< frame length in samples
-	int frame_len_bits;	///< frame_len = 1 << frame_len_bits
-	int nb_block_sizes;	///< number of block sizes
+	/** Frame length in samples. */
+	int frame_len;
+	/** log2 of frame_len. */
+	int frame_len_bits;
+	/** Number of block sizes. */
+	int nb_block_sizes;
 	/* block info */
 	int reset_block_lengths;
-	int block_len_bits;	///< log2 of current block length
-	int next_block_len_bits;	///< log2 of next block length
-	int prev_block_len_bits;	///< log2 of prev block length
-	int block_len;		///< block length in samples
-	int block_pos;		///< current position in frame
-	uint8_t ms_stereo;	///< true if mid/side stereo mode
-	uint8_t channel_coded[MAX_CHANNELS];	///< true if channel is coded
-	int exponents_bsize[MAX_CHANNELS];	///< log2 ratio frame/exp. length
+	/** log2 of current block length. */
+	int block_len_bits;
+	/** log2 of next block length. */
+	int next_block_len_bits;
+	/** log2 of previous block length. */
+	int prev_block_len_bits;
+	/** Block length in samples. */
+	int block_len;
+	/** Current position in frame. */
+	int block_pos;
+	/** True if mid/side stereo mode. */
+	uint8_t ms_stereo;
+	/** True if channel is coded. */
+	uint8_t channel_coded[MAX_CHANNELS];
+	/** log2 ratio frame/exp. length. */
+	int exponents_bsize[MAX_CHANNELS];
+
 	float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
 	float max_exponent[MAX_CHANNELS];
 	int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
@@ -106,9 +125,9 @@ struct private_wmadec_data {
 	float output[BLOCK_MAX_SIZE * 2];
 	struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
 	float *windows[BLOCK_NB_SIZES];
-	/* output buffer for one frame and the last for IMDCT windowing */
+	/** Output buffer for one frame and the last for IMDCT windowing. */
 	float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
-	/* last frame info */
+	/** Last frame info. */
 	uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4];	/* padding added */
 	int last_bitoffset;
 	int last_superframe_len;
@@ -131,16 +150,17 @@ struct private_wmadec_data {
 #define VLCBITS 9
 #define VLCMAX ((22 + VLCBITS - 1) / VLCBITS)
 
-DECLARE_ALIGNED(16, float, ff_sine_128[128]);
-DECLARE_ALIGNED(16, float, ff_sine_256[256]);
-DECLARE_ALIGNED(16, float, ff_sine_512[512]);
-DECLARE_ALIGNED(16, float, ff_sine_1024[1024]);
-DECLARE_ALIGNED(16, float, ff_sine_2048[2048]);
-DECLARE_ALIGNED(16, float, ff_sine_4096[4096]);
+#define SINE_WINDOW(x) float sine_ ## x[x] __a_aligned(16)
+
+SINE_WINDOW(128);
+SINE_WINDOW(256);
+SINE_WINDOW(512);
+SINE_WINDOW(1024);
+SINE_WINDOW(2048);
+SINE_WINDOW(4096);
 
-static float *ff_sine_windows[6] = {
-	ff_sine_128, ff_sine_256, ff_sine_512, ff_sine_1024,
-	ff_sine_2048, ff_sine_4096
+static float *sine_windows[6] = {
+	sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
 };
 
 /* Generate a sine window. */
@@ -207,7 +227,6 @@ static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
 	int a, b, pos, lpos, k, block_len, i, j, n;
 	const uint8_t *table;
 
-	pwd->coefs_start = 0;
 	for (k = 0; k < pwd->nb_block_sizes; k++) {
 		block_len = pwd->frame_len >> k;
 
@@ -285,13 +304,12 @@ static int wma_init(struct private_wmadec_data *pwd)
 		return -E_WMA_BAD_PARAMS;
 
 	/* compute MDCT block size */
-	if (ahi->sample_rate <= 16000) {
+	if (ahi->sample_rate <= 16000)
 		pwd->frame_len_bits = 9;
-	} else if (ahi->sample_rate <= 22050) {
+	else if (ahi->sample_rate <= 22050)
 		pwd->frame_len_bits = 10;
-	} else {
+	else
 		pwd->frame_len_bits = 11;
-	}
 	pwd->frame_len = 1 << pwd->frame_len_bits;
 	if (pwd->use_variable_block_len) {
 		int nb_max, nb;
@@ -348,24 +366,22 @@ static int wma_init(struct private_wmadec_data *pwd)
 			high_freq = high_freq * 0.5;
 		else
 			high_freq = high_freq * 0.3;
-	} else if (sample_rate1 == 11025) {
+	} else if (sample_rate1 == 11025)
 		high_freq = high_freq * 0.7;
-	} else if (sample_rate1 == 8000) {
-		if (bps <= 0.625) {
+	else if (sample_rate1 == 8000) {
+		if (bps <= 0.625)
 			high_freq = high_freq * 0.5;
-		} else if (bps > 0.75) {
+		else if (bps > 0.75)
 			pwd->use_noise_coding = 0;
-		} else {
+		else
 			high_freq = high_freq * 0.65;
-		}
 	} else {
-		if (bps >= 0.8) {
+		if (bps >= 0.8)
 			high_freq = high_freq * 0.75;
-		} else if (bps >= 0.6) {
+		else if (bps >= 0.6)
 			high_freq = high_freq * 0.6;
-		} else {
+		else
 			high_freq = high_freq * 0.5;
-		}
 	}
 	PARA_INFO_LOG("channels=%d sample_rate=%d "
 		"bitrate=%d block_align=%d\n",
@@ -383,8 +399,8 @@ static int wma_init(struct private_wmadec_data *pwd)
 	for (i = 0; i < pwd->nb_block_sizes; i++) {
 		int n;
 		n = 1 << (pwd->frame_len_bits - i);
-		sine_window_init(ff_sine_windows[pwd->frame_len_bits - i - 7], n);
-		pwd->windows[i] = ff_sine_windows[pwd->frame_len_bits - i - 7];
+		sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
+		pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
 	}
 
 	pwd->reset_block_lengths = 1;
@@ -481,15 +497,15 @@ static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_dat
 	if (pwd->use_noise_coding) {
 		PARA_INFO_LOG("using noise coding\n");
 		init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
-			sizeof(ff_wma_hgain_huffbits), ff_wma_hgain_huffbits,
-			ff_wma_hgain_huffcodes, 2);
+			sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
+			wma_hgain_huffcodes, 2);
 	}
 
 	if (pwd->use_exp_vlc) {
 		PARA_INFO_LOG("using exp_vlc\n");
 		init_vlc(&pwd->exp_vlc, EXPVLCBITS,
-		sizeof(ff_wma_scale_huffbits), ff_wma_scale_huffbits,
-		ff_wma_scale_huffcodes, 4);
+		sizeof(wma_scale_huffbits), wma_scale_huffbits,
+		wma_scale_huffcodes, 4);
 	} else {
 		PARA_INFO_LOG("using curve\n");
 		wma_lsp_to_curve_init(pwd, pwd->frame_len);
@@ -560,7 +576,7 @@ static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
 			val = get_bits(&pwd->gb, 3);
 		else
 			val = get_bits(&pwd->gb, 4);
-		lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
+		lsp_coefs[i] = wma_lsp_codebook[i][val];
 	}
 
 	wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
@@ -584,7 +600,7 @@ static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
 	while (q < q_end) {
 		code = get_vlc(&pwd->gb, pwd->exp_vlc.table, EXPVLCBITS, EXPMAX);
 		if (code < 0)
-			return -1;
+			return code;
 		/* NOTE: this offset is the same as MPEG4 AAC ! */
 		last_exp += code - 60;
 		/* XXX: use a table */
@@ -677,16 +693,161 @@ static int wma_total_gain_to_bits(int total_gain)
 		return 9;
 }
 
+static int compute_high_band_values(struct private_wmadec_data *pwd,
+		int bsize, int nb_coefs[MAX_CHANNELS])
+{
+	int ch;
+
+	if (!pwd->use_noise_coding)
+		return 0;
+	for (ch = 0; ch < pwd->ahi.channels; ch++) {
+		int i, m, a;
+		if (!pwd->channel_coded[ch])
+			continue;
+		m = pwd->exponent_high_sizes[bsize];
+		for (i = 0; i < m; i++) {
+			a = get_bit(&pwd->gb);
+			pwd->high_band_coded[ch][i] = a;
+			if (!a)
+				continue;
+			nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
+		}
+	}
+	for (ch = 0; ch < pwd->ahi.channels; ch++) {
+		int i, n, val;
+		if (!pwd->channel_coded[ch])
+			continue;
+		n = pwd->exponent_high_sizes[bsize];
+		val = (int)0x80000000;
+		for (i = 0; i < n; i++) {
+			if (!pwd->high_band_coded[ch][i])
+				continue;
+			if (val == (int)0x80000000)
+				val = get_bits(&pwd->gb, 7) - 19;
+			else {
+				int code = get_vlc(&pwd->gb,
+					pwd->hgain_vlc.table, HGAINVLCBITS,
+					HGAINMAX);
+				if (code < 0)
+					return code;
+				val += code - 18;
+			}
+			pwd->high_band_values[ch][i] = val;
+		}
+	}
+	return 1;
+}
+
+static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
+		int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
+{
+	int ch;
+	float mdct_norm = 1.0 / (pwd->block_len / 2);
+
+	for (ch = 0; ch < pwd->ahi.channels; ch++) {
+		int16_t *coefs1;
+		float *coefs, *exponents, mult, mult1, noise;
+		int i, j, n, n1, last_high_band, esize;
+		float exp_power[HIGH_BAND_MAX_SIZE];
+
+		if (!pwd->channel_coded[ch])
+			continue;
+		coefs1 = pwd->coefs1[ch];
+		exponents = pwd->exponents[ch];
+		esize = pwd->exponents_bsize[ch];
+		mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
+		mult *= mdct_norm;
+		coefs = pwd->coefs[ch];
+		if (!pwd->use_noise_coding) {
+			/* XXX: optimize more */
+			n = nb_coefs[ch];
+			for (i = 0; i < n; i++)
+				*coefs++ = coefs1[i] *
+					exponents[i << bsize >> esize] * mult;
+			n = pwd->block_len - pwd->coefs_end[bsize];
+			for (i = 0; i < n; i++)
+				*coefs++ = 0.0;
+			continue;
+		}
+		mult1 = mult;
+		n1 = pwd->exponent_high_sizes[bsize];
+		/* compute power of high bands */
+		exponents = pwd->exponents[ch] +
+			(pwd->high_band_start[bsize] << bsize);
+		last_high_band = 0; /* avoid warning */
+		for (j = 0; j < n1; j++) {
+			n = pwd->exponent_high_bands[
+				pwd->frame_len_bits - pwd->block_len_bits][j];
+			if (pwd->high_band_coded[ch][j]) {
+				float e2, val;
+				e2 = 0;
+				for (i = 0; i < n; i++) {
+					val = exponents[i << bsize >> esize];
+					e2 += val * val;
+				}
+				exp_power[j] = e2 / n;
+				last_high_band = j;
+			}
+			exponents += n << bsize;
+		}
+		/* main freqs and high freqs */
+		exponents = pwd->exponents[ch];
+		for (j = -1; j < n1; j++) {
+			if (j < 0)
+				n = pwd->high_band_start[bsize];
+			else
+				n = pwd->exponent_high_bands[pwd->frame_len_bits
+					- pwd->block_len_bits][j];
+			if (j >= 0 && pwd->high_band_coded[ch][j]) {
+				/* use noise with specified power */
+				mult1 = sqrt(exp_power[j]
+					/ exp_power[last_high_band]);
+				/* XXX: use a table */
+				mult1 = mult1 * pow(10,
+					pwd->high_band_values[ch][j] * 0.05);
+				mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
+				mult1 *= mdct_norm;
+				for (i = 0; i < n; i++) {
+					noise = pwd->noise_table[pwd->noise_index];
+					pwd->noise_index = (pwd->noise_index + 1)
+						& (NOISE_TAB_SIZE - 1);
+					*coefs++ = noise * exponents[
+						i << bsize >> esize] * mult1;
+				}
+				exponents += n << bsize;
+			} else {
+				/* coded values + small noise */
+				for (i = 0; i < n; i++) {
+					noise = pwd->noise_table[pwd->noise_index];
+					pwd->noise_index = (pwd->noise_index + 1)
+						& (NOISE_TAB_SIZE - 1);
+					*coefs++ = ((*coefs1++) + noise) *
+						exponents[i << bsize >> esize]
+						* mult;
+				}
+				exponents += n << bsize;
+			}
+		}
+		/* very high freqs: noise */
+		n = pwd->block_len - pwd->coefs_end[bsize];
+		mult1 = mult * exponents[((-1 << bsize)) >> esize];
+		for (i = 0; i < n; i++) {
+			*coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
+			pwd->noise_index = (pwd->noise_index + 1)
+				& (NOISE_TAB_SIZE - 1);
+		}
+	}
+}
+
 /**
- * @return 0 if OK. 1 if last block of frame. return -1 if
- * unrecorrable error.
+ * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
+ * errors.
  */
 static int wma_decode_block(struct private_wmadec_data *pwd)
 {
-	int n, v, ch, code, bsize;
+	int ret, n, v, ch, code, bsize;
 	int coef_nb_bits, total_gain;
 	int nb_coefs[MAX_CHANNELS];
-	float mdct_norm;
 
 	/* compute current block length */
 	if (pwd->use_variable_block_len) {
@@ -696,11 +857,11 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 			pwd->reset_block_lengths = 0;
 			v = get_bits(&pwd->gb, n);
 			if (v >= pwd->nb_block_sizes)
-				return -1;
+				return -E_WMA_BLOCK_SIZE;
 			pwd->prev_block_len_bits = pwd->frame_len_bits - v;
 			v = get_bits(&pwd->gb, n);
 			if (v >= pwd->nb_block_sizes)
-				return -1;
+				return -E_WMA_BLOCK_SIZE;
 			pwd->block_len_bits = pwd->frame_len_bits - v;
 		} else {
 			/* update block lengths */
@@ -709,7 +870,7 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 		}
 		v = get_bits(&pwd->gb, n);
 		if (v >= pwd->nb_block_sizes)
-			return -1;
+			return -E_WMA_BLOCK_SIZE;
 		pwd->next_block_len_bits = pwd->frame_len_bits - v;
 	} else {
 		/* fixed block len */
@@ -739,8 +900,10 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 	if (!v)
 		goto next;
 
-	/* read total gain and extract corresponding number of bits for
-	   coef escape coding */
+	/*
+	 * Read total gain and extract corresponding number of bits for coef
+	 * escape coding.
+	 */
 	total_gain = 1;
 	for (;;) {
 		int a = get_bits(&pwd->gb, 7);
@@ -752,70 +915,24 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 	coef_nb_bits = wma_total_gain_to_bits(total_gain);
 
 	/* compute number of coefficients */
-	n = pwd->coefs_end[bsize] - pwd->coefs_start;
+	n = pwd->coefs_end[bsize];
 	for (ch = 0; ch < pwd->ahi.channels; ch++)
 		nb_coefs[ch] = n;
 
-	/* complex coding */
-	if (pwd->use_noise_coding) {
-		for (ch = 0; ch < pwd->ahi.channels; ch++) {
-			if (pwd->channel_coded[ch]) {
-				int i, m, a;
-				m = pwd->exponent_high_sizes[bsize];
-				for (i = 0; i < m; i++) {
-					a = get_bit(&pwd->gb);
-					pwd->high_band_coded[ch][i] = a;
-					/* if noise coding, the coefficients are not transmitted */
-					if (a)
-						nb_coefs[ch] -=
-						    pwd->
-						    exponent_high_bands[bsize]
-						    [i];
-				}
-			}
-		}
-		for (ch = 0; ch < pwd->ahi.channels; ch++) {
-			if (pwd->channel_coded[ch]) {
-				int i, val;
-
-				n = pwd->exponent_high_sizes[bsize];
-				val = (int) 0x80000000;
-				for (i = 0; i < n; i++) {
-					if (pwd->high_band_coded[ch][i]) {
-						if (val == (int) 0x80000000) {
-							val =
-							    get_bits(&pwd->gb,
-								     7) - 19;
-						} else {
-							code =
-							    get_vlc(&pwd->gb,
-								     pwd->
-								     hgain_vlc.
-								     table,
-								     HGAINVLCBITS,
-								     HGAINMAX);
-							if (code < 0)
-								return -1;
-							val += code - 18;
-						}
-						pwd->high_band_values[ch][i] =
-						    val;
-					}
-				}
-			}
-		}
-	}
+	ret = compute_high_band_values(pwd, bsize, nb_coefs);
+	if (ret < 0)
+		return ret;
 
 	/* exponents can be reused in short blocks. */
 	if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
 		for (ch = 0; ch < pwd->ahi.channels; ch++) {
 			if (pwd->channel_coded[ch]) {
 				if (pwd->use_exp_vlc) {
-					if (decode_exp_vlc(pwd, ch) < 0)
-						return -1;
-				} else {
+					ret = decode_exp_vlc(pwd, ch);
+					if (ret < 0)
+						return ret;
+				} else
 					decode_exp_lsp(pwd, ch);
-				}
 				pwd->exponents_bsize[ch] = bsize;
 			}
 		}
@@ -846,7 +963,7 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 			code = get_vlc(&pwd->gb, coef_vlc->table,
 				VLCBITS, VLCMAX);
 			if (code < 0)
-				return -1;
+				return code;
 			if (code == 1) /* EOB */
 				break;
 			if (code == 0) { /* escape */
@@ -869,172 +986,10 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 				break;
 		}
 	}
-
-	/* normalize */
-	{
-		int n4 = pwd->block_len / 2;
-		mdct_norm = 1.0 / (float) n4;
-	}
-
-	/* finally compute the MDCT coefficients */
-	for (ch = 0; ch < pwd->ahi.channels; ch++) {
-		if (pwd->channel_coded[ch]) {
-			int16_t *coefs1;
-			float *coefs, *exponents, mult, mult1, noise;
-			int i, j, n1, last_high_band, esize;
-			float exp_power[HIGH_BAND_MAX_SIZE];
-
-			coefs1 = pwd->coefs1[ch];
-			exponents = pwd->exponents[ch];
-			esize = pwd->exponents_bsize[ch];
-			mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
-			mult *= mdct_norm;
-			coefs = pwd->coefs[ch];
-			if (pwd->use_noise_coding) {
-				mult1 = mult;
-				/* very low freqs : noise */
-				for (i = 0; i < pwd->coefs_start; i++) {
-					*coefs++ =
-					    pwd->noise_table[pwd->noise_index] *
-					    exponents[i << bsize >> esize] *
-					    mult1;
-					pwd->noise_index =
-					    (pwd->noise_index +
-					     1) & (NOISE_TAB_SIZE - 1);
-				}
-
-				n1 = pwd->exponent_high_sizes[bsize];
-
-				/* compute power of high bands */
-				exponents = pwd->exponents[ch] +
-				    (pwd->high_band_start[bsize] << bsize);
-				last_high_band = 0;	/* avoid warning */
-				for (j = 0; j < n1; j++) {
-					n = pwd->exponent_high_bands[pwd->
-								   frame_len_bits
-								   -
-								   pwd->
-								   block_len_bits]
-					    [j];
-					if (pwd->high_band_coded[ch][j]) {
-						float e2, val;
-						e2 = 0;
-						for (i = 0; i < n; i++) {
-							val = exponents[i << bsize
-								      >> esize];
-							e2 += val * val;
-						}
-						exp_power[j] = e2 / n;
-						last_high_band = j;
-					}
-					exponents += n << bsize;
-				}
-
-				/* main freqs and high freqs */
-				exponents =
-				    pwd->exponents[ch] +
-				    (pwd->coefs_start << bsize);
-				for (j = -1; j < n1; j++) {
-					if (j < 0) {
-						n = pwd->high_band_start[bsize] -
-						    pwd->coefs_start;
-					} else {
-						n = pwd->exponent_high_bands[pwd->
-									   frame_len_bits
-									   -
-									   pwd->
-									   block_len_bits]
-						    [j];
-					}
-					if (j >= 0 && pwd->high_band_coded[ch][j]) {
-						/* use noise with specified power */
-						mult1 =
-						    sqrt(exp_power[j] /
-							 exp_power
-							 [last_high_band]);
-						/* XXX: use a table */
-						mult1 =
-						    mult1 * pow(10,
-								pwd->
-								high_band_values
-								[ch][j] * 0.05);
-						mult1 =
-						    mult1 /
-						    (pwd->max_exponent[ch] *
-						     pwd->noise_mult);
-						mult1 *= mdct_norm;
-						for (i = 0; i < n; i++) {
-							noise =
-							    pwd->noise_table[pwd->
-									   noise_index];
-							pwd->noise_index =
-							    (pwd->noise_index +
-							     1) &
-							    (NOISE_TAB_SIZE -
-							     1);
-							*coefs++ =
-							    noise *
-							    exponents[i << bsize
-								      >> esize]
-							    * mult1;
-						}
-						exponents += n << bsize;
-					} else {
-						/* coded values + small noise */
-						for (i = 0; i < n; i++) {
-							noise =
-							    pwd->noise_table[pwd->
-									   noise_index];
-							pwd->noise_index =
-							    (pwd->noise_index +
-							     1) &
-							    (NOISE_TAB_SIZE -
-							     1);
-							*coefs++ =
-							    ((*coefs1++) +
-							     noise) *
-							    exponents[i << bsize
-								      >> esize]
-							    * mult;
-						}
-						exponents += n << bsize;
-					}
-				}
-
-				/* very high freqs : noise */
-				n = pwd->block_len - pwd->coefs_end[bsize];
-				mult1 =
-				    mult * exponents[((-1 << bsize)) >> esize];
-				for (i = 0; i < n; i++) {
-					*coefs++ =
-					    pwd->noise_table[pwd->noise_index] *
-					    mult1;
-					pwd->noise_index =
-					    (pwd->noise_index +
-					     1) & (NOISE_TAB_SIZE - 1);
-				}
-			} else {
-				/* XXX: optimize more */
-				for (i = 0; i < pwd->coefs_start; i++)
-					*coefs++ = 0.0;
-				n = nb_coefs[ch];
-				for (i = 0; i < n; i++) {
-					*coefs++ =
-					    coefs1[i] *
-					    exponents[i << bsize >> esize] *
-					    mult;
-				}
-				n = pwd->block_len - pwd->coefs_end[bsize];
-				for (i = 0; i < n; i++)
-					*coefs++ = 0.0;
-			}
-		}
-	}
-
+	compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
 	if (pwd->ms_stereo && pwd->channel_coded[1]) {
 		float a, b;
 		int i;
-
 		/*
 		 * Nominal case for ms stereo: we do it before mdct.
 		 *
@@ -1053,7 +1008,6 @@ static int wma_decode_block(struct private_wmadec_data *pwd)
 			pwd->coefs[1][i] = a - b;
 		}
 	}
-
 next:
 	for (ch = 0; ch < pwd->ahi.channels; ch++) {
 		int n4, index;
@@ -1105,7 +1059,7 @@ static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
 	for (;;) {
 		ret = wma_decode_block(pwd);
 		if (ret < 0)
-			return -1;
+			return ret;
 		if (ret)
 			break;
 	}
@@ -1133,7 +1087,6 @@ static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
 {
 	int ret;
 	int16_t *samples;
-	static int frame_count;
 
 	if (buf_size == 0) {
 		pwd->last_superframe_len = 0;
@@ -1184,10 +1137,9 @@ static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
 			 * This frame is stored in the last superframe and in
 			 * the current one.
 			 */
-			ret = -E_WMA_DECODE;
-			if (wma_decode_frame(pwd, samples) < 0)
+			ret = wma_decode_frame(pwd, samples);
+			if (ret < 0)
 				goto fail;
-			frame_count++;
 			samples += pwd->ahi.channels * pwd->frame_len;
 		}
 
@@ -1201,10 +1153,9 @@ static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
 
 		pwd->reset_block_lengths = 1;
 		for (i = 0; i < nb_frames; i++) {
-			ret = -E_WMA_DECODE;
-			if (wma_decode_frame(pwd, samples) < 0)
+			ret = wma_decode_frame(pwd, samples);
+			if (ret < 0)
 				goto fail;
-			frame_count++;
 			samples += pwd->ahi.channels * pwd->frame_len;
 		}
 
@@ -1225,16 +1176,14 @@ static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
 		if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
 			goto fail;
 		/* single frame decode */
-		ret = -E_WMA_DECODE;
-		if (wma_decode_frame(pwd, samples) < 0)
+		ret = wma_decode_frame(pwd, samples);
+		if (ret < 0)
 			goto fail;
-		frame_count++;
 		samples += pwd->ahi.channels * pwd->frame_len;
 	}
-	PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
-		"outbytes: %d, eaten: %d\n",
-		frame_count, pwd->frame_len, pwd->block_len,
-		(int8_t *) samples - (int8_t *) data, pwd->ahi.block_align);
+	PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
+		pwd->frame_len, pwd->block_len,
+		(int)((int8_t *)samples - (int8_t *)data), pwd->ahi.block_align);
 	*data_size = (int8_t *)samples - (int8_t *)data;
 	return pwd->ahi.block_align;
 fail:
@@ -1243,14 +1192,107 @@ fail:
 	return ret;
 }
 
+static void wmadec_close(struct filter_node *fn)
+{
+	struct private_wmadec_data *pwd = fn->private_data;
+
+	if (!pwd)
+		return;
+	wmadec_cleanup(pwd);
+	free(fn->buf);
+	fn->buf = NULL;
+	free(fn->private_data);
+	fn->private_data = NULL;
+}
+
+static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
+{
+	struct filter_node *fn = btr_context(btrn);
+	struct private_wmadec_data *pwd = fn->private_data;
+
+	if (!strcmp(cmd, "samplerate")) {
+		if (pwd->ahi.sample_rate == 0)
+			return -ERRNO_TO_PARA_ERROR(ENAVAIL);
+		*result = make_message("%u", pwd->ahi.sample_rate);
+		return 1;
+	}
+	if (!strcmp(cmd, "channels")) {
+		if (pwd->ahi.channels == 0)
+			return -ERRNO_TO_PARA_ERROR(ENAVAIL);
+		*result = make_message("%u", pwd->ahi.channels);
+		return 1;
+	}
+	return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+}
+
+#define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
+
+static void wmadec_post_select(__a_unused struct sched *s, struct task *t)
+{
+	struct filter_node *fn = container_of(t, struct filter_node, task);
+	int ret, converted;
+	struct private_wmadec_data *pwd = fn->private_data;
+	struct btr_node *btrn = fn->btrn;
+	size_t len;
+	char *in;
+
+next_buffer:
+	converted = 0;
+	t->error = 0;
+	ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
+	if (ret < 0)
+		goto err;
+	if (ret == 0)
+		return;
+	btr_merge(btrn, fn->min_iqs);
+	len = btr_next_buffer(btrn, (char **)&in);
+	ret = -E_WMADEC_EOF;
+	if (len < fn->min_iqs)
+		goto err;
+	if (!pwd) {
+		ret = wma_decode_init(in, len, &pwd);
+		if (ret < 0)
+			goto err;
+		if (ret == 0) {
+			fn->min_iqs += 4096;
+			goto next_buffer;
+		}
+		fn->min_iqs = WMA_FRAME_SKIP + pwd->ahi.block_align;
+		fn->private_data = pwd;
+		converted = pwd->ahi.header_len;
+		goto success;
+	}
+	for (;;) {
+		char *out;
+		int out_size = WMA_OUTPUT_BUFFER_SIZE;
+		if (converted + fn->min_iqs > len)
+			break;
+		out = para_malloc(WMA_OUTPUT_BUFFER_SIZE);
+		ret = wma_decode_superframe(pwd, out,
+			&out_size, (uint8_t *)in + converted + WMA_FRAME_SKIP,
+			len - WMA_FRAME_SKIP);
+		if (ret < 0) {
+			free(out);
+			goto err;
+		}
+		btr_add_output(out, out_size, btrn);
+		converted += ret + WMA_FRAME_SKIP;
+	}
+success:
+	btr_consume(btrn, converted);
+	goto next_buffer;
+err:
+	assert(ret < 0);
+	t->error = ret;
+	btr_remove_node(btrn);
+}
+
 static ssize_t wmadec_convert(char *inbuffer, size_t len,
 		struct filter_node *fn)
 {
-	int ret, out_size = fn->bufsize - fn->loaded;
+	int ret, converted = 0;
 	struct private_wmadec_data *pwd = fn->private_data;
 
-	if (out_size < 128 * 1024)
-		return 0;
 	if (len <= WMA_FRAME_SKIP)
 		return 0;
 	if (!pwd) {
@@ -1262,29 +1304,22 @@ static ssize_t wmadec_convert(char *inbuffer, size_t len,
 		fn->fc->samplerate = pwd->ahi.sample_rate;
 		return pwd->ahi.header_len;
 	}
-	/* skip 31 bytes */
-	if (len <= WMA_FRAME_SKIP + pwd->ahi.block_align)
-		return 0;
-	ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
-		&out_size, (uint8_t *)inbuffer + WMA_FRAME_SKIP,
-		len - WMA_FRAME_SKIP);
-	if (ret < 0)
-		return ret;
-	fn->loaded += out_size;
-	return ret + WMA_FRAME_SKIP;
-}
-
-static void wmadec_close(struct filter_node *fn)
-{
-	struct private_wmadec_data *pwd = fn->private_data;
-
-	if (!pwd)
-		return;
-	wmadec_cleanup(pwd);
-	free(fn->buf);
-	fn->buf = NULL;
-	free(fn->private_data);
-	fn->private_data = NULL;
+	for (;;) {
+		int out_size;
+		if (converted + WMA_FRAME_SKIP + pwd->ahi.block_align > len)
+			break;
+		out_size = fn->bufsize - fn->loaded;
+		if (out_size < 128 * 1024)
+			break;
+		ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
+			&out_size, (uint8_t *)inbuffer + converted + WMA_FRAME_SKIP,
+			len - WMA_FRAME_SKIP);
+		if (ret < 0)
+			return ret;
+		fn->loaded += out_size;
+		converted += ret + WMA_FRAME_SKIP;
+	}
+	return converted;
 }
 
 static void wmadec_open(struct filter_node *fn)
@@ -1293,6 +1328,7 @@ static void wmadec_open(struct filter_node *fn)
 	fn->buf = para_malloc(fn->bufsize);
 	fn->private_data = NULL;
 	fn->loaded = 0;
+	fn->min_iqs = 4096;
 }
 
 /**
@@ -1305,4 +1341,7 @@ void wmadec_filter_init(struct filter *f)
 	f->open = wmadec_open;
 	f->close = wmadec_close;
 	f->convert = wmadec_convert;
+	f->execute = wmadec_execute;
+	f->pre_select = generic_filter_pre_select;
+	f->post_select = wmadec_post_select;
 }