added wma decoder

Originally committed as revision 1090 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 1339 insertions, 0 deletions

diff --git a/libavcodec/wmadec.c b/libavcodec/wmadec.c
new file mode 100644
index 0000000000..da8707f07b
--- /dev/null
+++ b/libavcodec/wmadec.c
@@ -0,0 +1,1339 @@
+/*
+ * WMA compatible decoder
+ * Copyright (c) 2002 The FFmpeg Project.
+ *
+ * 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 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "avcodec.h"
+#include "dsputil.h"
+
+//#define DEBUG_PARAMS
+//#define DEBUG_TRACE
+
+/* size of blocks */
+#define BLOCK_MIN_BITS 7
+#define BLOCK_MAX_BITS 11
+#define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
+
+#define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
+
+/* XXX: find exact max size */
+#define HIGH_BAND_MAX_SIZE 16
+
+#define NB_LSP_COEFS 10
+
+/* XXX: is it a suitable value ? */
+#define MAX_CODED_SUPERFRAME_SIZE 4096
+
+#define MAX_CHANNELS 2
+
+#define NOISE_TAB_SIZE 8192
+
+#define LSP_POW_BITS 7
+
+typedef struct WMADecodeContext {
+    GetBitContext gb;
+    int sample_rate;
+    int nb_channels;
+    int bit_rate;
+    int version; /* 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) */
+    int block_align;
+    int use_bit_reservoir;
+    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 */
+    int byte_offset_bits;
+    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 */
+    int exponent_high_sizes[BLOCK_NB_SIZES];
+    int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE]; 
+    VLC hgain_vlc;
+    
+    /* coded values in high bands */
+    int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
+    int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
+
+    /* there are two possible tables for spectral coefficients */
+    VLC coef_vlc[2];
+    uint16_t *run_table[2];
+    uint16_t *level_table[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 */
+    /* 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_num; /* block number in current frame */
+    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 */
+    float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
+    float max_exponent[MAX_CHANNELS];
+    int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
+    float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
+    MDCTContext mdct_ctx[BLOCK_NB_SIZES];
+    float *windows[BLOCK_NB_SIZES];
+    FFTSample mdct_tmp[BLOCK_MAX_SIZE]; /* temporary storage for imdct */
+    /* output buffer for one frame and the last for IMDCT windowing */
+    float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
+    /* last frame info */
+    uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
+    int last_bitoffset;
+    int last_superframe_len;
+    float noise_table[NOISE_TAB_SIZE];
+    int noise_index;
+    float noise_mult; /* XXX: suppress that and integrate it in the noise array */
+    /* lsp_to_curve tables */
+    float lsp_cos_table[BLOCK_MAX_SIZE];
+    float lsp_pow_e_table[256];
+    float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
+    float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
+} WMADecodeContext;
+
+typedef struct CoefVLCTable {
+    int n; /* total number of codes */
+    const uint32_t *huffcodes; /* VLC bit values */
+    const uint8_t *huffbits;   /* VLC bit size */
+    const uint16_t *levels; /* table to build run/level tables */
+} CoefVLCTable;
+
+static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len);
+
+#include "wmadata.h"
+
+#ifdef DEBUG_TRACE
+
+int frame_count;
+
+static FILE *flog;
+
+void trace(const char *fmt, ...)
+{
+    va_list ap;
+    
+
+    if (!flog) {
+        flog = fopen("/tmp/out.log", "w");
+        setlinebuf(flog);
+    }
+
+    va_start(ap, fmt);
+    vfprintf(flog, fmt, ap);
+    va_end(ap);
+}
+
+#define get_bits(s, n) get_bits_trace(s, n)
+#define get_vlc(s, vlc) get_vlc_trace(s, vlc)
+
+unsigned int get_bits_trace(GetBitContext *s, int n)
+{
+    unsigned int val;
+    val = (get_bits)(s, n);
+    trace("get_bits(%d) : 0x%x\n", n, val);
+    return val;
+}
+
+static int get_vlc_trace(GetBitContext *s, VLC *vlc)
+{
+    int code;
+    code = (get_vlc)(s, vlc);
+    trace("get_vlc() : %d\n", code);
+    return code;
+}
+
+static void dump_shorts(const char *name, const short *tab, int n)
+{
+    int i;
+
+    trace("%s[%d]:\n", name, n);
+    for(i=0;i<n;i++) {
+        if ((i & 7) == 0)
+            trace("%4d: ", i);
+        trace(" %5d.0", tab[i]);
+        if ((i & 7) == 7)
+            trace("\n");
+    }
+}
+
+static void dump_floats(const char *name, int prec, const float *tab, int n)
+{
+    int i;
+
+    trace("%s[%d]:\n", name, n);
+    for(i=0;i<n;i++) {
+        if ((i & 7) == 0)
+            trace("%4d: ", i);
+        trace(" %8.*f", prec, tab[i]);
+        if ((i & 7) == 7)
+            trace("\n");
+    }
+    if ((i & 7) != 0)
+        trace("\n");
+}
+
+#else
+
+#define trace(fmt, ...)
+
+#endif
+
+/* XXX: use same run/length optimization as mpeg decoders */
+static void init_coef_vlc(VLC *vlc, 
+                          uint16_t **prun_table, uint16_t **plevel_table,
+                          const CoefVLCTable *vlc_table)
+{
+    int n = vlc_table->n;
+    const uint8_t *table_bits = vlc_table->huffbits;
+    const uint32_t *table_codes = vlc_table->huffcodes;
+    const uint16_t *levels_table = vlc_table->levels;
+    uint16_t *run_table, *level_table;
+    const uint16_t *p;
+    int i, l, j, level;
+
+    init_vlc(vlc, 9, n, table_bits, 1, 1, table_codes, 4, 4);
+
+    run_table = malloc(n * sizeof(uint16_t));
+    level_table = malloc(n * sizeof(uint16_t));
+    p = levels_table;
+    i = 2;
+    level = 1;
+    while (i < n) {
+        l = *p++;
+        for(j=0;j<l;j++) {
+            run_table[i] = j;
+            level_table[i] = level;
+            i++;
+        }
+        level++;
+    }
+    *prun_table = run_table;
+    *plevel_table = level_table;
+}
+
+static int wma_decode_init(AVCodecContext * avctx)
+{
+    WMADecodeContext *s = avctx->priv_data;
+    int i, flags1, flags2;
+    float *window;
+    uint8_t *extradata;
+    float bps1, high_freq, bps;
+    int sample_rate1;
+    int coef_vlc_table;
+    
+    s->sample_rate = avctx->sample_rate;
+    s->nb_channels = avctx->channels;
+    s->bit_rate = avctx->bit_rate;
+    s->block_align = avctx->block_align;
+
+    if (avctx->codec_id == CODEC_ID_WMAV1) {
+        s->version = 1;
+    } else {
+        s->version = 2;
+    }
+    
+    /* extract flag infos */
+    flags1 = 0;
+    flags2 = 0;
+    extradata = avctx->extradata;
+    if (s->version == 1 && avctx->extradata_size >= 4) {
+        flags1 = extradata[0] | (extradata[1] << 8);
+        flags2 = extradata[2] | (extradata[3] << 8);
+    } else if (s->version == 2 && avctx->extradata_size >= 6) {
+        flags1 = extradata[0] | (extradata[1] << 8) | 
+            (extradata[2] << 16) | (extradata[3] << 24);
+        flags2 = extradata[4] | (extradata[5] << 8);
+    }
+    s->use_exp_vlc = flags2 & 0x0001;
+    s->use_bit_reservoir = flags2 & 0x0002;
+    s->use_variable_block_len = flags2 & 0x0004;
+
+    /* compute MDCT block size */
+    if (s->sample_rate <= 16000) {
+        s->frame_len_bits = 9;
+    } else if (s->sample_rate <= 32000) {
+        s->frame_len_bits = 10;
+    } else {
+        s->frame_len_bits = 11;
+    }
+    s->frame_len = 1 << s->frame_len_bits;
+    if (s->use_variable_block_len) {
+        s->nb_block_sizes = s->frame_len_bits - BLOCK_MIN_BITS + 1;
+    } else {
+        s->nb_block_sizes = 1;
+    }
+
+    /* init rate dependant parameters */
+    s->use_noise_coding = 1;
+    high_freq = s->sample_rate * 0.5;
+
+    /* if version 2, then the rates are normalized */
+    sample_rate1 = s->sample_rate;
+    if (s->version == 2) {
+        if (sample_rate1 >= 44100) 
+            sample_rate1 = 44100;
+        else if (sample_rate1 >= 22050) 
+            sample_rate1 = 22050;
+        else if (sample_rate1 >= 16000) 
+            sample_rate1 = 16000;
+        else if (sample_rate1 >= 11025) 
+            sample_rate1 = 11025;
+        else if (sample_rate1 >= 8000) 
+            sample_rate1 = 8000;
+    }
+
+    bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
+    s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0)) + 2;
+
+    /* compute high frequency value and choose if noise coding should
+       be activated */
+    bps1 = bps;
+    if (s->nb_channels == 2)
+        bps1 = bps * 1.6;
+    if (sample_rate1 == 44100) {
+        if (bps1 >= 0.61)
+            s->use_noise_coding = 0;
+        else
+            high_freq = high_freq * 0.4;
+    } else if (sample_rate1 == 22050) {
+        if (bps1 >= 1.16)
+            s->use_noise_coding = 0;
+        else if (bps1 >= 0.72) 
+            high_freq = high_freq * 0.7;
+        else
+            high_freq = high_freq * 0.6;
+    } else if (sample_rate1 == 16000) {
+        if (bps > 0.5)
+            high_freq = high_freq * 0.5;
+        else
+            high_freq = high_freq * 0.3;
+    } else if (sample_rate1 == 11025) {
+        high_freq = high_freq * 0.7;
+    } else if (sample_rate1 == 8000) {
+        if (bps <= 0.625) {
+            high_freq = high_freq * 0.5;
+        } else if (bps > 0.75) {
+            s->use_noise_coding = 0;
+        } else {
+            high_freq = high_freq * 0.65;
+        }
+    } else {
+        if (bps >= 0.8) {
+            high_freq = high_freq * 0.75;
+        } else if (bps >= 0.6) {
+            high_freq = high_freq * 0.6;
+        } else {
+            high_freq = high_freq * 0.5;
+        }
+    }
+#ifdef DEBUG_PARAMS
+    printf("flags1=0x%x flags2=0x%x\n", flags1, flags2);
+    printf("version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
+           s->version, s->nb_channels, s->sample_rate, s->bit_rate, 
+           s->block_align);
+    printf("bps=%f bps1=%f high_freq=%f bitoffset=%d\n", 
+           bps, bps1, high_freq, s->byte_offset_bits);
+    printf("use_noise_coding=%d use_exp_vlc=%d\n",
+           s->use_noise_coding, s->use_exp_vlc);
+#endif
+
+    /* compute the scale factor band sizes for each MDCT block size */
+    {
+        int a, b, pos, lpos, k, block_len, i, j, n;
+        const uint8_t *table;
+        
+        if (s->version == 1) {
+            s->coefs_start = 3;
+        } else {
+            s->coefs_start = 0;
+        }
+        for(k = 0; k < s->nb_block_sizes; k++) {
+            block_len = s->frame_len >> k;
+
+            if (s->version == 1) {
+                lpos = 0;
+                for(i=0;i<25;i++) {
+                    a = wma_critical_freqs[i];
+                    b = s->sample_rate;
+                    pos = ((block_len * 2 * a)  + (b >> 1)) / b;
+                    if (pos > block_len) 
+                        pos = block_len;
+                    s->exponent_bands[0][i] = pos - lpos;
+                    if (pos >= block_len) {
+                        i++;
+                        break;
+                    }
+                    lpos = pos;
+                }
+                s->exponent_sizes[0] = i;
+            } else {
+                /* hardcoded tables */
+                table = NULL;
+                a = s->frame_len_bits - BLOCK_MIN_BITS - k;
+                if (a < 3) {
+                    if (s->sample_rate >= 44100)
+                        table = exponent_band_44100[a];
+                    else if (s->sample_rate >= 32000)
+                        table = exponent_band_32000[a];
+                    else if (s->sample_rate >= 22050)
+                        table = exponent_band_22050[a];
+                }
+                if (table) {
+                    n = *table++;
+                    for(i=0;i<n;i++)
+                        s->exponent_bands[k][i] = table[i];
+                    s->exponent_sizes[k] = n;
+                } else {
+                    j = 0;
+                    lpos = 0;
+                    for(i=0;i<25;i++) {
+                        a = wma_critical_freqs[i];
+                        b = s->sample_rate;
+                        pos = ((block_len * 2 * a)  + (b << 1)) / (4 * b);
+                        pos <<= 2;
+                        if (pos > block_len) 
+                            pos = block_len;
+                        if (pos > lpos)
+                            s->exponent_bands[k][j++] = pos - lpos;
+                        if (pos >= block_len)
+                            break;
+                        lpos = pos;
+                    }
+                    s->exponent_sizes[k] = j;
+                }
+            }
+
+            /* max number of coefs */
+            s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
+            /* high freq computation */
+            s->high_band_start[k] = (int)((block_len * 2 * high_freq) / 
+                                          s->sample_rate + 0.5);
+            n = s->exponent_sizes[k];
+            j = 0;
+            pos = 0;
+            for(i=0;i<n;i++) {
+                int start, end;
+                start = pos;
+                pos += s->exponent_bands[k][i];
+                end = pos;
+                if (start < s->high_band_start[k])
+                    start = s->high_band_start[k];
+                if (end > s->coefs_end[k])
+                    end = s->coefs_end[k];
+                if (end > start)
+                    s->exponent_high_bands[k][j++] = end - start;
+            }
+            s->exponent_high_sizes[k] = j;
+#if 0
+            trace("%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
+                  s->frame_len >> k, 
+                  s->coefs_end[k],
+                  s->high_band_start[k],
+                  s->exponent_high_sizes[k]);
+            for(j=0;j<s->exponent_high_sizes[k];j++)
+                trace(" %d", s->exponent_high_bands[k][j]);
+            trace("\n");
+#endif
+        }
+    }
+
+#ifdef DEBUG_TRACE
+    {
+        int i, j;
+        for(i = 0; i < s->nb_block_sizes; i++) {
+            trace("%5d: n=%2d:", 
+                   s->frame_len >> i, 
+                   s->exponent_sizes[i]);
+            for(j=0;j<s->exponent_sizes[i];j++)
+                trace(" %d", s->exponent_bands[i][j]);
+            trace("\n");
+        }
+    }
+#endif
+
+    /* init MDCT */
+    for(i = 0; i < s->nb_block_sizes; i++)
+        mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1);
+    
+    /* init MDCT windows : simple sinus window */
+    for(i = 0; i < s->nb_block_sizes; i++) {
+        int n, j;
+        float alpha;
+        n = 1 << (s->frame_len_bits - i);
+        window = av_malloc(sizeof(float) * n);
+        alpha = M_PI / (2.0 * n);
+        for(j=0;j<n;j++) {
+            window[n - j - 1] = sin((j + 0.5) * alpha);
+        }
+        s->windows[i] = window;
+    }
+
+    s->reset_block_lengths = 1;
+    
+    if (s->use_noise_coding) {
+
+        /* init the noise generator */
+        if (s->use_exp_vlc)
+            s->noise_mult = 0.02;
+        else
+            s->noise_mult = 0.04;
+               
+#if defined(DEBUG_TRACE)
+        for(i=0;i<NOISE_TAB_SIZE;i++)
+            s->noise_table[i] = 1.0 * s->noise_mult;
+#else
+        {
+            unsigned int seed;
+            float norm;
+            seed = 1;
+            norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
+            for(i=0;i<NOISE_TAB_SIZE;i++) {
+                seed = seed * 314159 + 1;
+                s->noise_table[i] = (float)((int)seed) * norm;
+            }
+        }
+#endif
+        init_vlc(&s->hgain_vlc, 9, sizeof(hgain_huffbits), 
+                 hgain_huffbits, 1, 1,
+                 hgain_huffcodes, 2, 2);
+    }
+
+    if (s->use_exp_vlc) {
+        init_vlc(&s->exp_vlc, 9, sizeof(scale_huffbits), 
+                 scale_huffbits, 1, 1,
+                 scale_huffcodes, 4, 4);
+    } else {
+        wma_lsp_to_curve_init(s, s->frame_len);
+    }
+
+    /* choose the VLC tables for the coefficients */
+    coef_vlc_table = 2;
+    if (s->sample_rate >= 32000) {
+        if (bps1 < 0.72)
+            coef_vlc_table = 0;
+        else if (bps1 < 1.16)
+            coef_vlc_table = 1;
+    }
+
+    init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
+                  &coef_vlcs[coef_vlc_table * 2]);
+    init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
+                  &coef_vlcs[coef_vlc_table * 2 + 1]);
+    return 0;
+}
+
+/* interpolate values for a bigger or smaller block. The block must
+   have multiple sizes */
+static void interpolate_array(float *scale, int old_size, int new_size)
+{
+    int i, j, jincr, k;
+    float v;
+
+    if (new_size > old_size) {
+        jincr = new_size / old_size;
+        j = new_size;
+        for(i = old_size - 1; i >=0; i--) {
+            v = scale[i];
+            k = jincr;
+            do {
+                scale[--j] = v;
+            } while (--k);
+        }
+    } else if (new_size < old_size) {
+        j = 0;
+        jincr = old_size / new_size;
+        for(i = 0; i < new_size; i++) {
+            scale[i] = scale[j];
+            j += jincr;
+        }
+    }
+}
+
+/* compute x^-0.25 with an exponent and mantissa table. We use linear
+   interpolation to reduce the mantissa table size at a small speed
+   expense (linear interpolation approximately doubles the number of
+   bits of precision). */
+static inline float pow_m1_4(WMADecodeContext *s, float x)
+{
+    union {
+        float f;
+        unsigned int v;
+    } u, t;
+    unsigned int e, m;
+    float a, b;
+
+    u.f = x;
+    e = u.v >> 23;
+    m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
+    /* build interpolation scale: 1 <= t < 2. */
+    t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
+    a = s->lsp_pow_m_table1[m];
+    b = s->lsp_pow_m_table2[m];
+    return s->lsp_pow_e_table[e] * (a + b * t.f);
+}
+
+static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len)
+{  
+    float wdel, a, b;
+    int i, e, m;
+
+    wdel = M_PI / frame_len;
+    for(i=0;i<frame_len;i++)
+        s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
+
+    /* tables for x^-0.25 computation */
+    for(i=0;i<256;i++) {
+        e = i - 126;
+        s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
+    }
+
+    /* NOTE: these two tables are needed to avoid two operations in
+       pow_m1_4 */
+    b = 1.0;
+    for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
+        m = (1 << LSP_POW_BITS) + i;
+        a = (float)m * (0.5 / (1 << LSP_POW_BITS));
+        a = pow(a, -0.25);
+        s->lsp_pow_m_table1[i] = 2 * a - b;
+        s->lsp_pow_m_table2[i] = b - a;
+        b = a;
+    }
+#if 0
+    for(i=1;i<20;i++) {
+        float v, r1, r2;
+        v = 5.0 / i;
+        r1 = pow_m1_4(s, v);
+        r2 = pow(v,-0.25);
+        printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1);
+    }
+#endif
+}
+
+/* NOTE: We use the same code as Vorbis here */
+/* XXX: optimize it further with SSE/3Dnow */
+static void wma_lsp_to_curve(WMADecodeContext *s, 
+                             float *out, float *val_max_ptr, 
+                             int n, float *lsp)
+{
+    int i, j;
+    float p, q, w, v, val_max;
+
+    val_max = 0;
+    for(i=0;i<n;i++) {
+        p = 0.5f;
+        q = 0.5f;
+        w = s->lsp_cos_table[i];
+        for(j=1;j<NB_LSP_COEFS;j+=2){
+            q *= w - lsp[j - 1];
+            p *= w - lsp[j];
+        }
+        p *= p * (2.0f - w);
+        q *= q * (2.0f + w);
+        v = p + q;
+        v = pow_m1_4(s, v);
+        if (v > val_max)
+            val_max = v;
+        out[i] = v;
+    }
+    *val_max_ptr = val_max;
+}
+
+/* decode exponents coded with LSP coefficients (same idea as Vorbis) */
+static void decode_exp_lsp(WMADecodeContext *s, int ch)
+{
+    float lsp_coefs[NB_LSP_COEFS];
+    int val, i;
+
+    for(i = 0; i < NB_LSP_COEFS; i++) {
+        if (i == 0 || i >= 8)
+            val = get_bits(&s->gb, 3);
+        else
+            val = get_bits(&s->gb, 4);
+        lsp_coefs[i] = lsp_codebook[i][val];
+    }
+
+    wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
+                     s->block_len, lsp_coefs);
+}
+
+/* decode exponents coded with VLC codes */
+static int decode_exp_vlc(WMADecodeContext *s, int ch)
+{
+    int last_exp, n, code;
+    const uint16_t *ptr, *band_ptr;
+    float v, *q, max_scale, *q_end;
+    
+    band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
+    ptr = band_ptr;
+    q = s->exponents[ch];
+    q_end = q + s->block_len;
+    max_scale = 0;
+    if (s->version == 1) {
+        last_exp = get_bits(&s->gb, 5) + 10;
+        /* XXX: use a table */
+        v = pow(10, last_exp * (1.0 / 16.0));
+        max_scale = v;
+        n = *ptr++;
+        do {
+            *q++ = v;
+        } while (--n);
+    }
+    last_exp = 36;
+    while (q < q_end) {
+        code = get_vlc(&s->gb, &s->exp_vlc);
+        if (code < 0)
+            return -1;
+        /* NOTE: this offset is the same as MPEG4 AAC ! */
+        last_exp += code - 60;
+        /* XXX: use a table */
+        v = pow(10, last_exp * (1.0 / 16.0));
+        if (v > max_scale)
+            max_scale = v;
+        n = *ptr++;
+        do {
+            *q++ = v;
+        } while (--n);
+    }
+    s->max_exponent[ch] = max_scale;
+    return 0;
+}
+
+/* return 0 if OK. return 1 if last block of frame. return -1 if
+   unrecorrable error. */
+static int wma_decode_block(WMADecodeContext *s)
+{
+    int n, v, a, ch, code, bsize;
+    int coef_nb_bits, total_gain, parse_exponents;
+    float window[BLOCK_MAX_SIZE * 2];
+    int nb_coefs[MAX_CHANNELS];
+    float mdct_norm;
+
+    trace("***decode_block: %d:%d\n", frame_count - 1, s->block_num);
+
+    /* compute current block length */
+    if (s->use_variable_block_len) {
+        n = av_log2(s->nb_block_sizes - 1) + 1;
+    
+        if (s->reset_block_lengths) {
+            s->reset_block_lengths = 0;
+            v = get_bits(&s->gb, n);
+            if (v >= s->nb_block_sizes)
+                return -1;
+            s->prev_block_len_bits = s->frame_len_bits - v;
+            v = get_bits(&s->gb, n);
+            if (v >= s->nb_block_sizes)
+                return -1;
+            s->block_len_bits = s->frame_len_bits - v;
+        } else {
+            /* update block lengths */
+            s->prev_block_len_bits = s->block_len_bits;
+            s->block_len_bits = s->next_block_len_bits;
+        }
+        v = get_bits(&s->gb, n);
+        if (v >= s->nb_block_sizes)
+            return -1;
+        s->next_block_len_bits = s->frame_len_bits - v;
+    } else {
+        /* fixed block len */
+        s->next_block_len_bits = s->frame_len_bits;
+        s->prev_block_len_bits = s->frame_len_bits;
+        s->block_len_bits = s->frame_len_bits;
+    }
+
+    /* now check if the block length is coherent with the frame length */
+    s->block_len = 1 << s->block_len_bits;
+    if ((s->block_pos + s->block_len) > s->frame_len)
+        return -1;
+
+    if (s->nb_channels == 2) {
+        s->ms_stereo = get_bits(&s->gb, 1);
+    }
+    v = 0;
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        a = get_bits(&s->gb, 1);
+        s->channel_coded[ch] = a;
+        v |= a;
+    }
+    /* if no channel coded, no need to go further */
+    /* XXX: fix potential framing problems */
+    if (!v)
+        goto next;
+
+    bsize = s->frame_len_bits - s->block_len_bits;
+
+    /* read total gain and extract corresponding number of bits for
+       coef escape coding */
+    total_gain = 1;
+    for(;;) {
+        a = get_bits(&s->gb, 7);
+        total_gain += a;
+        if (a != 127)
+            break;
+    }
+    
+    if (total_gain < 15)
+        coef_nb_bits = 13;
+    else if (total_gain < 32)
+        coef_nb_bits = 12;
+    else if (total_gain < 40)
+        coef_nb_bits = 11;
+    else if (total_gain < 45)
+        coef_nb_bits = 10;
+    else
+        coef_nb_bits = 9;
+
+    /* compute number of coefficients */
+    n = s->coefs_end[bsize] - s->coefs_start;
+    for(ch = 0; ch < s->nb_channels; ch++)
+        nb_coefs[ch] = n;
+
+    /* complex coding */
+    if (s->use_noise_coding) {
+
+        for(ch = 0; ch < s->nb_channels; ch++) {
+            if (s->channel_coded[ch]) {
+                int i, n, a;
+                n = s->exponent_high_sizes[bsize];
+                for(i=0;i<n;i++) {
+                    a = get_bits(&s->gb, 1);
+                    s->high_band_coded[ch][i] = a;
+                    /* if noise coding, the coefficients are not transmitted */
+                    if (a)
+                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
+                }
+            }
+        }
+        for(ch = 0; ch < s->nb_channels; ch++) {
+            if (s->channel_coded[ch]) {
+                int i, n, val, code;
+
+                n = s->exponent_high_sizes[bsize];
+                val = (int)0x80000000;
+                for(i=0;i<n;i++) {
+                    if (s->high_band_coded[ch][i]) {
+                        if (val == (int)0x80000000) {
+                            val = get_bits(&s->gb, 7) - 19;
+                        } else {
+                            code = get_vlc(&s->gb, &s->hgain_vlc);
+                            if (code < 0)
+                                return -1;
+                            val += code - 18;
+                        }
+                        s->high_band_values[ch][i] = val;
+                    }
+                }
+            }
+        }
+    }
+           
+    /* exposant can be interpolated in short blocks. */
+    parse_exponents = 1;
+    if (s->block_len_bits != s->frame_len_bits) {
+        parse_exponents = get_bits(&s->gb, 1);
+    }
+    
+    if (parse_exponents) {
+        for(ch = 0; ch < s->nb_channels; ch++) {
+            if (s->channel_coded[ch]) {
+                if (s->use_exp_vlc) {
+                    if (decode_exp_vlc(s, ch) < 0)
+                        return -1;
+                } else {
+                    decode_exp_lsp(s, ch);
+                }
+            }
+        }
+    } else {
+        for(ch = 0; ch < s->nb_channels; ch++) {
+            if (s->channel_coded[ch]) {
+                interpolate_array(s->exponents[ch], 1 << s->prev_block_len_bits, 
+                                  s->block_len);
+            }
+        }
+    }
+
+    /* parse spectral coefficients : just RLE encoding */
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            VLC *coef_vlc;
+            int level, run, sign, tindex;
+            int16_t *ptr, *eptr;
+            const int16_t *level_table, *run_table;
+
+            /* special VLC tables are used for ms stereo because
+               there is potentially less energy there */
+            tindex = (ch == 1 && s->ms_stereo);
+            coef_vlc = &s->coef_vlc[tindex];
+            run_table = s->run_table[tindex];
+            level_table = s->level_table[tindex];
+            /* XXX: optimize */
+            ptr = &s->coefs1[ch][0];
+            eptr = ptr + nb_coefs[ch];
+            memset(ptr, 0, s->block_len * sizeof(int16_t));
+            for(;;) {
+                code = get_vlc(&s->gb, coef_vlc);
+                if (code < 0)
+                    return -1;
+                if (code == 1) {
+                    /* EOB */
+                    break;
+                } else if (code == 0) {
+                    /* escape */
+                    level = get_bits(&s->gb, coef_nb_bits);
+                    /* NOTE: this is rather suboptimal. reading
+                       block_len_bits would be better */
+                    run = get_bits(&s->gb, s->frame_len_bits);
+                } else {
+                    /* normal code */
+                    run = run_table[code];
+                    level = level_table[code];
+                }
+                sign = get_bits(&s->gb, 1);
+                if (!sign)
+                    level = -level;
+                ptr += run;
+                if (ptr >= eptr)
+                    return -1;
+                *ptr++ = level;
+                /* NOTE: EOB can be omitted */
+                if (ptr >= eptr)
+                    break;
+            }
+        }
+        if (s->version == 1 && s->nb_channels >= 2) {
+            align_get_bits(&s->gb);
+        }
+    }
+     
+    /* normalize */
+    {
+        int n4 = s->block_len / 2;
+        mdct_norm = 1.0 / (float)n4;
+        if (s->version == 1) {
+            mdct_norm *= sqrt(n4);
+        }
+    }
+
+    /* finally compute the MDCT coefficients */
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            int16_t *coefs1;
+            float *coefs, *exponents, mult, mult1, noise, *exp_ptr;
+            int i, j, n, n1, last_high_band;
+            float exp_power[HIGH_BAND_MAX_SIZE];
+
+            coefs1 = s->coefs1[ch];
+            exponents = s->exponents[ch];
+            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
+            mult *= mdct_norm;
+            coefs = s->coefs[ch];
+            if (s->use_noise_coding) {
+                mult1 = mult;
+                /* very low freqs : noise */
+                for(i = 0;i < s->coefs_start; i++) {
+                    *coefs++ = s->noise_table[s->noise_index] * (*exponents++) * mult1;
+                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
+                }
+                
+                n1 = s->exponent_high_sizes[bsize];
+
+                /* compute power of high bands */
+                exp_ptr = exponents + 
+                    s->high_band_start[bsize] - 
+                    s->coefs_start;
+                last_high_band = 0; /* avoid warning */
+                for(j=0;j<n1;j++) {
+                    n = s->exponent_high_bands[s->frame_len_bits - 
+                                              s->block_len_bits][j];
+                    if (s->high_band_coded[ch][j]) {
+                        float e2, v;
+                        e2 = 0;
+                        for(i = 0;i < n; i++) {
+                            v = exp_ptr[i];
+                            e2 += v * v;
+                        }
+                        exp_power[j] = e2 / n;
+                        last_high_band = j;
+                        trace("%d: power=%f (%d)\n", j, exp_power[j], n);
+                    }
+                    exp_ptr += n;
+                }
+
+                /* main freqs and high freqs */
+                for(j=-1;j<n1;j++) {
+                    if (j < 0) {
+                        n = s->high_band_start[bsize] - 
+                            s->coefs_start;
+                    } else {
+                        n = s->exponent_high_bands[s->frame_len_bits - 
+                                                  s->block_len_bits][j];
+                    }
+                    if (j >= 0 && s->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, s->high_band_values[ch][j] * 0.05);
+                        mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
+                        mult1 *= mdct_norm;
+                        for(i = 0;i < n; i++) {
+                            noise = s->noise_table[s->noise_index];
+                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
+                            *coefs++ = (*exponents++) * noise * mult1;
+                        }
+                    } else {
+                        /* coded values + small noise */
+                        for(i = 0;i < n; i++) {
+                            noise = s->noise_table[s->noise_index];
+                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
+                            *coefs++ = ((*coefs1++) + noise) * (*exponents++) * mult;
+                        }
+                    }
+                }
+
+                /* very high freqs : noise */
+                n = s->block_len - s->coefs_end[bsize];
+                mult1 = mult * exponents[-1];
+                for(i = 0; i < n; i++) {
+                    *coefs++ = s->noise_table[s->noise_index] * mult1;
+                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
+                }
+            } else {
+                /* XXX: optimize more */
+                for(i = 0;i < s->coefs_start; i++)
+                    *coefs++ = 0.0;
+                n = nb_coefs[ch];
+                for(i = 0;i < n; i++) {
+                    *coefs++ = coefs1[i] * exponents[i] * mult;
+                }
+                n = s->block_len - s->coefs_end[bsize];
+                for(i = 0;i < n; i++)
+                    *coefs++ = 0.0;
+            }
+        }
+    }
+
+#ifdef DEBUG_TRACE
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            dump_floats("exponents", 3, s->exponents[ch], s->block_len);
+            dump_floats("coefs", 1, s->coefs[ch], s->block_len);
+        }
+    }
+#endif
+    
+    if (s->ms_stereo && s->channel_coded[1]) {
+        float a, b;
+        int i;
+
+        /* nominal case for ms stereo: we do it before mdct */
+        /* no need to optimize this case because it should almost
+           never happen */
+        if (!s->channel_coded[0]) {
+#ifdef DEBUG_TRACE
+            trace("rare ms-stereo case happened\n");
+#endif
+            memset(s->coefs[0], 0, sizeof(float) * s->block_len);
+            s->channel_coded[0] = 1;
+        }
+        
+        for(i = 0; i < s->block_len; i++) {
+            a = s->coefs[0][i];
+            b = s->coefs[1][i];
+            s->coefs[0][i] = a + b;
+            s->coefs[1][i] = a - b;
+        }
+    }
+
+    /* build the window : we ensure that when the windows overlap
+       their squared sum is always 1 (MDCT reconstruction rule) */
+    /* XXX: merge with output */
+    {
+        int i, next_block_len, block_len, prev_block_len, n;
+        float *wptr;
+
+        block_len = s->block_len;
+        prev_block_len = 1 << s->prev_block_len_bits;
+        next_block_len = 1 << s->next_block_len_bits;
+
+        /* right part */
+        wptr = window + block_len;
+        if (block_len <= next_block_len) {
+            for(i=0;i<block_len;i++)
+                *wptr++ = s->windows[bsize][i];
+        } else {
+            /* overlap */
+            n = (block_len / 2) - (next_block_len / 2);
+            for(i=0;i<n;i++)
+                *wptr++ = 1.0;
+            for(i=0;i<next_block_len;i++)
+                *wptr++ = s->windows[s->frame_len_bits - s->next_block_len_bits][i];
+            for(i=0;i<n;i++)
+                *wptr++ = 0.0;
+        }
+
+        /* left part */
+        wptr = window + block_len;
+        if (block_len <= prev_block_len) {
+            for(i=0;i<block_len;i++)
+                *--wptr = s->windows[bsize][i];
+        } else {
+            /* overlap */
+            n = (block_len / 2) - (prev_block_len / 2);
+            for(i=0;i<n;i++)
+                *--wptr = 1.0;
+            for(i=0;i<prev_block_len;i++)
+                *--wptr = s->windows[s->frame_len_bits - s->prev_block_len_bits][i];
+            for(i=0;i<n;i++)
+                *--wptr = 0.0;
+        }
+    }
+
+    
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        if (s->channel_coded[ch]) {
+            FFTSample output[BLOCK_MAX_SIZE * 2];
+            float *ptr;
+            int i, n4, index, n;
+
+            n = s->block_len;
+            n4 = s->block_len / 2;
+            imdct_calc(&s->mdct_ctx[bsize], 
+                       output, s->coefs[ch], s->mdct_tmp);
+
+            /* XXX: optimize all that by build the window and
+               multipying/adding at the same time */
+            /* multiply by the window */
+            for(i=0;i<n * 2;i++) {
+                output[i] *= window[i];
+            }
+
+            /* add in the frame */
+            index = (s->frame_len / 2) + s->block_pos - n4;
+            ptr = &s->frame_out[ch][index];
+            for(i=0;i<n * 2;i++) {
+                *ptr += output[i];
+                ptr++;
+            }
+
+            /* specific fast case for ms-stereo : add to second
+               channel if it is not coded */
+            if (s->ms_stereo && !s->channel_coded[1]) {
+                ptr = &s->frame_out[1][index];
+                for(i=0;i<n * 2;i++) {
+                    *ptr += output[i];
+                    ptr++;
+                }
+            }
+        }
+    }
+ next:
+    /* update block number */
+    s->block_num++;
+    s->block_pos += s->block_len;
+    if (s->block_pos >= s->frame_len)
+        return 1;
+    else
+        return 0;
+}
+
+/* decode a frame of frame_len samples */
+static int wma_decode_frame(WMADecodeContext *s, int16_t *samples)
+{
+    int ret, i, n, a, ch, incr;
+    int16_t *ptr;
+    float *iptr;
+
+    trace("***decode_frame: %d size=%d\n", frame_count++, s->frame_len);
+
+    /* read each block */
+    s->block_num = 0;
+    s->block_pos = 0;
+    for(;;) {
+        ret = wma_decode_block(s);
+        if (ret < 0) 
+            return -1;
+        if (ret)
+            break;
+    }
+
+    /* convert frame to integer */
+    n = s->frame_len;
+    incr = s->nb_channels;
+    for(ch = 0; ch < s->nb_channels; ch++) {
+        ptr = samples + ch;
+        iptr = s->frame_out[ch];
+
+        for(i=0;i<n;i++) {
+            a = lrint(*iptr++);
+            if (a > 32767)
+                a = 32767;
+            else if (a < -32768)
+                a = -32768;
+            *ptr = a;
+            ptr += incr;
+        }
+        /* prepare for next block */
+        memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
+                s->frame_len * sizeof(float));
+        /* XXX: suppress this */
+        memset(&s->frame_out[ch][s->frame_len], 0, 
+               s->frame_len * sizeof(float));
+    }
+
+#ifdef DEBUG_TRACE
+    dump_shorts("samples", samples, n * s->nb_channels);
+#endif
+    return 0;
+}
+
+static int wma_decode_superframe(AVCodecContext *avctx, 
+                                 void *data, int *data_size,
+                                 UINT8 *buf, int buf_size)
+{
+    WMADecodeContext *s = avctx->priv_data;
+    int nb_frames, bit_offset, i, pos, len;
+    uint8_t *q;
+    int16_t *samples;
+    
+    trace("***decode_superframe:\n");
+
+    samples = data;
+
+    init_get_bits(&s->gb, buf, buf_size);
+    
+    if (s->use_bit_reservoir) {
+        /* read super frame header */
+        get_bits(&s->gb, 4); /* super frame index */
+        nb_frames = get_bits(&s->gb, 4) - 1;
+
+        bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
+
+        if (s->last_superframe_len > 0) {
+            //        printf("skip=%d\n", s->last_bitoffset);
+            /* add bit_offset bits to last frame */
+            if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) > 
+                MAX_CODED_SUPERFRAME_SIZE)
+                return -1;
+            q = s->last_superframe + s->last_superframe_len;
+            len = bit_offset;
+            while (len > 0) {
+                *q++ = (get_bits)(&s->gb, 8);
+                len -= 8;
+            }
+            if (len > 0) {
+                *q++ = (get_bits)(&s->gb, len) << (8 - len);
+            }
+            
+            /* XXX: bit_offset bits into last frame */
+            init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE);
+            /* skip unused bits */
+            if (s->last_bitoffset > 0)
+                skip_bits(&s->gb, s->last_bitoffset);
+            /* this frame is stored in the last superframe and in the
+               current one */
+            if (wma_decode_frame(s, samples) < 0)
+                return -1;
+            samples += s->nb_channels * s->frame_len;
+        }
+
+        /* read each frame starting from bit_offset */
+        pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
+        init_get_bits(&s->gb, buf + (pos >> 3), MAX_CODED_SUPERFRAME_SIZE - (pos >> 3));
+        len = pos & 7;
+        if (len > 0)
+            skip_bits(&s->gb, len);
+    
+        s->reset_block_lengths = 1;
+        for(i=0;i<nb_frames;i++) {
+            if (wma_decode_frame(s, samples) < 0)
+                return -1;
+            samples += s->nb_channels * s->frame_len;
+        }
+
+        /* we copy the end of the frame in the last frame buffer */
+        pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
+        s->last_bitoffset = pos & 7;
+        pos >>= 3;
+        len = buf_size - pos;
+        if (len > MAX_CODED_SUPERFRAME_SIZE) {
+            return -1;
+        }
+        s->last_superframe_len = len;
+        memcpy(s->last_superframe, buf + pos, len);
+    } else {
+        /* single frame decode */
+        if (wma_decode_frame(s, samples) < 0)
+            return -1;
+        samples += s->nb_channels * s->frame_len;
+    }
+    *data_size = (int8_t *)samples - (int8_t *)data;
+    return s->block_align;
+}
+
+static int wma_decode_end(AVCodecContext *avctx)
+{
+    WMADecodeContext *s = avctx->priv_data;
+    int i;
+
+    for(i = 0; i < s->nb_block_sizes; i++)
+        mdct_end(&s->mdct_ctx[i]);
+    for(i = 0; i < s->nb_block_sizes; i++)
+        av_free(s->windows[i]);
+
+    if (s->use_exp_vlc) {
+        free_vlc(&s->exp_vlc);
+    }
+    if (s->use_noise_coding) {
+        free_vlc(&s->hgain_vlc);
+    }
+    for(i = 0;i < 2; i++) {
+        free_vlc(&s->coef_vlc[i]);
+        av_free(s->run_table[i]);
+        av_free(s->level_table[i]);
+    }
+    
+    return 0;
+}
+
+AVCodec wmav1_decoder =
+{
+    "wmav1",
+    CODEC_TYPE_AUDIO,
+    CODEC_ID_WMAV1,
+    sizeof(WMADecodeContext),
+    wma_decode_init,
+    NULL,
+    wma_decode_end,
+    wma_decode_superframe,
+};
+
+AVCodec wmav2_decoder =
+{
+    "wmav2",
+    CODEC_TYPE_AUDIO,
+    CODEC_ID_WMAV2,
+    sizeof(WMADecodeContext),
+    wma_decode_init,
+    NULL,
+    wma_decode_end,
+    wma_decode_superframe,
+};