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libavcodec/wmaprodec.c

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00001 /*
00002  * Wmapro compatible decoder
00003  * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
00004  * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
00005  *
00006  * This file is part of Libav.
00007  *
00008  * Libav is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * Libav is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with Libav; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00089 #include "libavutil/intfloat.h"
00090 #include "libavutil/intreadwrite.h"
00091 #include "avcodec.h"
00092 #include "internal.h"
00093 #include "get_bits.h"
00094 #include "put_bits.h"
00095 #include "wmaprodata.h"
00096 #include "dsputil.h"
00097 #include "fmtconvert.h"
00098 #include "sinewin.h"
00099 #include "wma.h"
00100 
00102 #define WMAPRO_MAX_CHANNELS    8                             ///< max number of handled channels
00103 #define MAX_SUBFRAMES  32                                    ///< max number of subframes per channel
00104 #define MAX_BANDS      29                                    ///< max number of scale factor bands
00105 #define MAX_FRAMESIZE  32768                                 ///< maximum compressed frame size
00106 
00107 #define WMAPRO_BLOCK_MIN_BITS  6                                           ///< log2 of min block size
00108 #define WMAPRO_BLOCK_MAX_BITS 12                                           ///< log2 of max block size
00109 #define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS)                 ///< maximum block size
00110 #define WMAPRO_BLOCK_SIZES    (WMAPRO_BLOCK_MAX_BITS - WMAPRO_BLOCK_MIN_BITS + 1) ///< possible block sizes
00111 
00112 
00113 #define VLCBITS            9
00114 #define SCALEVLCBITS       8
00115 #define VEC4MAXDEPTH    ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
00116 #define VEC2MAXDEPTH    ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
00117 #define VEC1MAXDEPTH    ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
00118 #define SCALEMAXDEPTH   ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
00119 #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
00120 
00121 static VLC              sf_vlc;           
00122 static VLC              sf_rl_vlc;        
00123 static VLC              vec4_vlc;         
00124 static VLC              vec2_vlc;         
00125 static VLC              vec1_vlc;         
00126 static VLC              coef_vlc[2];      
00127 static float            sin64[33];        
00128 
00132 typedef struct {
00133     int16_t  prev_block_len;                          
00134     uint8_t  transmit_coefs;
00135     uint8_t  num_subframes;
00136     uint16_t subframe_len[MAX_SUBFRAMES];             
00137     uint16_t subframe_offset[MAX_SUBFRAMES];          
00138     uint8_t  cur_subframe;                            
00139     uint16_t decoded_samples;                         
00140     uint8_t  grouped;                                 
00141     int      quant_step;                              
00142     int8_t   reuse_sf;                                
00143     int8_t   scale_factor_step;                       
00144     int      max_scale_factor;                        
00145     int      saved_scale_factors[2][MAX_BANDS];       
00146     int8_t   scale_factor_idx;                        
00147     int*     scale_factors;                           
00148     uint8_t  table_idx;                               
00149     float*   coeffs;                                  
00150     uint16_t num_vec_coeffs;                          
00151     DECLARE_ALIGNED(32, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; 
00152 } WMAProChannelCtx;
00153 
00157 typedef struct {
00158     uint8_t num_channels;                                     
00159     int8_t  transform;                                        
00160     int8_t  transform_band[MAX_BANDS];                        
00161     float   decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
00162     float*  channel_data[WMAPRO_MAX_CHANNELS];                
00163 } WMAProChannelGrp;
00164 
00168 typedef struct WMAProDecodeCtx {
00169     /* generic decoder variables */
00170     AVCodecContext*  avctx;                         
00171     AVFrame          frame;                         
00172     DSPContext       dsp;                           
00173     FmtConvertContext fmt_conv;
00174     uint8_t          frame_data[MAX_FRAMESIZE +
00175                       FF_INPUT_BUFFER_PADDING_SIZE];
00176     PutBitContext    pb;                            
00177     FFTContext       mdct_ctx[WMAPRO_BLOCK_SIZES];  
00178     DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; 
00179     float*           windows[WMAPRO_BLOCK_SIZES];   
00180 
00181     /* frame size dependent frame information (set during initialization) */
00182     uint32_t         decode_flags;                  
00183     uint8_t          len_prefix;                    
00184     uint8_t          dynamic_range_compression;     
00185     uint8_t          bits_per_sample;               
00186     uint16_t         samples_per_frame;             
00187     uint16_t         log2_frame_size;
00188     int8_t           num_channels;                  
00189     int8_t           lfe_channel;                   
00190     uint8_t          max_num_subframes;
00191     uint8_t          subframe_len_bits;             
00192     uint8_t          max_subframe_len_bit;          
00193     uint16_t         min_samples_per_subframe;
00194     int8_t           num_sfb[WMAPRO_BLOCK_SIZES];   
00195     int16_t          sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS];                    
00196     int8_t           sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; 
00197     int16_t          subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; 
00198 
00199     /* packet decode state */
00200     GetBitContext    pgb;                           
00201     int              next_packet_start;             
00202     uint8_t          packet_offset;                 
00203     uint8_t          packet_sequence_number;        
00204     int              num_saved_bits;                
00205     int              frame_offset;                  
00206     int              subframe_offset;               
00207     uint8_t          packet_loss;                   
00208     uint8_t          packet_done;                   
00209 
00210     /* frame decode state */
00211     uint32_t         frame_num;                     
00212     GetBitContext    gb;                            
00213     int              buf_bit_size;                  
00214     uint8_t          drc_gain;                      
00215     int8_t           skip_frame;                    
00216     int8_t           parsed_all_subframes;          
00217 
00218     /* subframe/block decode state */
00219     int16_t          subframe_len;                  
00220     int8_t           channels_for_cur_subframe;     
00221     int8_t           channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS];
00222     int8_t           num_bands;                     
00223     int8_t           transmit_num_vec_coeffs;       
00224     int16_t*         cur_sfb_offsets;               
00225     uint8_t          table_idx;                     
00226     int8_t           esc_len;                       
00227 
00228     uint8_t          num_chgroups;                  
00229     WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS];  
00230 
00231     WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS];  
00232 } WMAProDecodeCtx;
00233 
00234 
00239 static void av_cold dump_context(WMAProDecodeCtx *s)
00240 {
00241 #define PRINT(a, b)     av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
00242 #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
00243 
00244     PRINT("ed sample bit depth", s->bits_per_sample);
00245     PRINT_HEX("ed decode flags", s->decode_flags);
00246     PRINT("samples per frame",   s->samples_per_frame);
00247     PRINT("log2 frame size",     s->log2_frame_size);
00248     PRINT("max num subframes",   s->max_num_subframes);
00249     PRINT("len prefix",          s->len_prefix);
00250     PRINT("num channels",        s->num_channels);
00251 }
00252 
00258 static av_cold int decode_end(AVCodecContext *avctx)
00259 {
00260     WMAProDecodeCtx *s = avctx->priv_data;
00261     int i;
00262 
00263     for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
00264         ff_mdct_end(&s->mdct_ctx[i]);
00265 
00266     return 0;
00267 }
00268 
00274 static av_cold int decode_init(AVCodecContext *avctx)
00275 {
00276     WMAProDecodeCtx *s = avctx->priv_data;
00277     uint8_t *edata_ptr = avctx->extradata;
00278     unsigned int channel_mask;
00279     int i;
00280     int log2_max_num_subframes;
00281     int num_possible_block_sizes;
00282 
00283     s->avctx = avctx;
00284     dsputil_init(&s->dsp, avctx);
00285     ff_fmt_convert_init(&s->fmt_conv, avctx);
00286     init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
00287 
00288     avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
00289 
00290     if (avctx->extradata_size >= 18) {
00291         s->decode_flags    = AV_RL16(edata_ptr+14);
00292         channel_mask       = AV_RL32(edata_ptr+2);
00293         s->bits_per_sample = AV_RL16(edata_ptr);
00295         for (i = 0; i < avctx->extradata_size; i++)
00296             av_dlog(avctx, "[%x] ", avctx->extradata[i]);
00297         av_dlog(avctx, "\n");
00298 
00299     } else {
00300         av_log_ask_for_sample(avctx, "Unknown extradata size\n");
00301         return AVERROR_INVALIDDATA;
00302     }
00303 
00305     s->log2_frame_size = av_log2(avctx->block_align) + 4;
00306 
00308     s->skip_frame  = 1; /* skip first frame */
00309     s->packet_loss = 1;
00310     s->len_prefix  = (s->decode_flags & 0x40);
00311 
00313     s->samples_per_frame = 1 << ff_wma_get_frame_len_bits(avctx->sample_rate,
00314                                                           3, s->decode_flags);
00315 
00317     log2_max_num_subframes       = ((s->decode_flags & 0x38) >> 3);
00318     s->max_num_subframes         = 1 << log2_max_num_subframes;
00319     if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
00320         s->max_subframe_len_bit = 1;
00321     s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
00322 
00323     num_possible_block_sizes     = log2_max_num_subframes + 1;
00324     s->min_samples_per_subframe  = s->samples_per_frame / s->max_num_subframes;
00325     s->dynamic_range_compression = (s->decode_flags & 0x80);
00326 
00327     if (s->max_num_subframes > MAX_SUBFRAMES) {
00328         av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
00329                s->max_num_subframes);
00330         return AVERROR_INVALIDDATA;
00331     }
00332 
00333     if (s->avctx->sample_rate <= 0) {
00334         av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
00335         return AVERROR_INVALIDDATA;
00336     }
00337 
00338     s->num_channels = avctx->channels;
00339 
00340     if (s->num_channels < 0) {
00341         av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n", s->num_channels);
00342         return AVERROR_INVALIDDATA;
00343     } else if (s->num_channels > WMAPRO_MAX_CHANNELS) {
00344         av_log_ask_for_sample(avctx, "unsupported number of channels\n");
00345         return AVERROR_PATCHWELCOME;
00346     }
00347 
00349     for (i = 0; i < s->num_channels; i++)
00350         s->channel[i].prev_block_len = s->samples_per_frame;
00351 
00353     s->lfe_channel = -1;
00354 
00355     if (channel_mask & 8) {
00356         unsigned int mask;
00357         for (mask = 1; mask < 16; mask <<= 1) {
00358             if (channel_mask & mask)
00359                 ++s->lfe_channel;
00360         }
00361     }
00362 
00363     INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
00364                     scale_huffbits, 1, 1,
00365                     scale_huffcodes, 2, 2, 616);
00366 
00367     INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
00368                     scale_rl_huffbits, 1, 1,
00369                     scale_rl_huffcodes, 4, 4, 1406);
00370 
00371     INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
00372                     coef0_huffbits, 1, 1,
00373                     coef0_huffcodes, 4, 4, 2108);
00374 
00375     INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
00376                     coef1_huffbits, 1, 1,
00377                     coef1_huffcodes, 4, 4, 3912);
00378 
00379     INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
00380                     vec4_huffbits, 1, 1,
00381                     vec4_huffcodes, 2, 2, 604);
00382 
00383     INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
00384                     vec2_huffbits, 1, 1,
00385                     vec2_huffcodes, 2, 2, 562);
00386 
00387     INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
00388                     vec1_huffbits, 1, 1,
00389                     vec1_huffcodes, 2, 2, 562);
00390 
00393     for (i = 0; i < num_possible_block_sizes; i++) {
00394         int subframe_len = s->samples_per_frame >> i;
00395         int x;
00396         int band = 1;
00397 
00398         s->sfb_offsets[i][0] = 0;
00399 
00400         for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
00401             int offset = (subframe_len * 2 * critical_freq[x])
00402                           / s->avctx->sample_rate + 2;
00403             offset &= ~3;
00404             if (offset > s->sfb_offsets[i][band - 1])
00405                 s->sfb_offsets[i][band++] = offset;
00406         }
00407         s->sfb_offsets[i][band - 1] = subframe_len;
00408         s->num_sfb[i]               = band - 1;
00409     }
00410 
00411 
00417     for (i = 0; i < num_possible_block_sizes; i++) {
00418         int b;
00419         for (b = 0; b < s->num_sfb[i]; b++) {
00420             int x;
00421             int offset = ((s->sfb_offsets[i][b]
00422                            + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
00423             for (x = 0; x < num_possible_block_sizes; x++) {
00424                 int v = 0;
00425                 while (s->sfb_offsets[x][v + 1] << x < offset)
00426                     ++v;
00427                 s->sf_offsets[i][x][b] = v;
00428             }
00429         }
00430     }
00431 
00433     for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
00434         ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
00435                      1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
00436                      / (1 << (s->bits_per_sample - 1)));
00437 
00439     for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
00440         const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
00441         ff_init_ff_sine_windows(win_idx);
00442         s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
00443     }
00444 
00446     for (i = 0; i < num_possible_block_sizes; i++) {
00447         int block_size = s->samples_per_frame >> i;
00448         int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
00449                      / s->avctx->sample_rate;
00450         s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
00451     }
00452 
00454     for (i = 0; i < 33; i++)
00455         sin64[i] = sin(i*M_PI / 64.0);
00456 
00457     if (avctx->debug & FF_DEBUG_BITSTREAM)
00458         dump_context(s);
00459 
00460     avctx->channel_layout = channel_mask;
00461 
00462     avcodec_get_frame_defaults(&s->frame);
00463     avctx->coded_frame = &s->frame;
00464 
00465     return 0;
00466 }
00467 
00474 static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
00475 {
00476     int frame_len_shift = 0;
00477     int subframe_len;
00478 
00480     if (offset == s->samples_per_frame - s->min_samples_per_subframe)
00481         return s->min_samples_per_subframe;
00482 
00484     if (s->max_subframe_len_bit) {
00485         if (get_bits1(&s->gb))
00486             frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
00487     } else
00488         frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
00489 
00490     subframe_len = s->samples_per_frame >> frame_len_shift;
00491 
00493     if (subframe_len < s->min_samples_per_subframe ||
00494         subframe_len > s->samples_per_frame) {
00495         av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
00496                subframe_len);
00497         return AVERROR_INVALIDDATA;
00498     }
00499     return subframe_len;
00500 }
00501 
00522 static int decode_tilehdr(WMAProDecodeCtx *s)
00523 {
00524     uint16_t num_samples[WMAPRO_MAX_CHANNELS];        
00525     uint8_t  contains_subframe[WMAPRO_MAX_CHANNELS];  
00526     int channels_for_cur_subframe = s->num_channels;  
00527     int fixed_channel_layout = 0;                     
00528     int min_channel_len = 0;                          
00529     int c;
00530 
00531     /* Should never consume more than 3073 bits (256 iterations for the
00532      * while loop when always the minimum amount of 128 samples is substracted
00533      * from missing samples in the 8 channel case).
00534      * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS  + 4)
00535      */
00536 
00538     for (c = 0; c < s->num_channels; c++)
00539         s->channel[c].num_subframes = 0;
00540 
00541     memset(num_samples, 0, sizeof(num_samples));
00542 
00543     if (s->max_num_subframes == 1 || get_bits1(&s->gb))
00544         fixed_channel_layout = 1;
00545 
00547     do {
00548         int subframe_len;
00549 
00551         for (c = 0; c < s->num_channels; c++) {
00552             if (num_samples[c] == min_channel_len) {
00553                 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
00554                    (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
00555                     contains_subframe[c] = 1;
00556                 else
00557                     contains_subframe[c] = get_bits1(&s->gb);
00558             } else
00559                 contains_subframe[c] = 0;
00560         }
00561 
00563         if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
00564             return AVERROR_INVALIDDATA;
00565 
00567         min_channel_len += subframe_len;
00568         for (c = 0; c < s->num_channels; c++) {
00569             WMAProChannelCtx* chan = &s->channel[c];
00570 
00571             if (contains_subframe[c]) {
00572                 if (chan->num_subframes >= MAX_SUBFRAMES) {
00573                     av_log(s->avctx, AV_LOG_ERROR,
00574                            "broken frame: num subframes > 31\n");
00575                     return AVERROR_INVALIDDATA;
00576                 }
00577                 chan->subframe_len[chan->num_subframes] = subframe_len;
00578                 num_samples[c] += subframe_len;
00579                 ++chan->num_subframes;
00580                 if (num_samples[c] > s->samples_per_frame) {
00581                     av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
00582                            "channel len > samples_per_frame\n");
00583                     return AVERROR_INVALIDDATA;
00584                 }
00585             } else if (num_samples[c] <= min_channel_len) {
00586                 if (num_samples[c] < min_channel_len) {
00587                     channels_for_cur_subframe = 0;
00588                     min_channel_len = num_samples[c];
00589                 }
00590                 ++channels_for_cur_subframe;
00591             }
00592         }
00593     } while (min_channel_len < s->samples_per_frame);
00594 
00595     for (c = 0; c < s->num_channels; c++) {
00596         int i;
00597         int offset = 0;
00598         for (i = 0; i < s->channel[c].num_subframes; i++) {
00599             av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
00600                     " len %i\n", s->frame_num, c, i,
00601                     s->channel[c].subframe_len[i]);
00602             s->channel[c].subframe_offset[i] = offset;
00603             offset += s->channel[c].subframe_len[i];
00604         }
00605     }
00606 
00607     return 0;
00608 }
00609 
00615 static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
00616                                         WMAProChannelGrp *chgroup)
00617 {
00618     int i;
00619     int offset = 0;
00620     int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
00621     memset(chgroup->decorrelation_matrix, 0, s->num_channels *
00622            s->num_channels * sizeof(*chgroup->decorrelation_matrix));
00623 
00624     for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
00625         rotation_offset[i] = get_bits(&s->gb, 6);
00626 
00627     for (i = 0; i < chgroup->num_channels; i++)
00628         chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
00629             get_bits1(&s->gb) ? 1.0 : -1.0;
00630 
00631     for (i = 1; i < chgroup->num_channels; i++) {
00632         int x;
00633         for (x = 0; x < i; x++) {
00634             int y;
00635             for (y = 0; y < i + 1; y++) {
00636                 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
00637                 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
00638                 int n = rotation_offset[offset + x];
00639                 float sinv;
00640                 float cosv;
00641 
00642                 if (n < 32) {
00643                     sinv = sin64[n];
00644                     cosv = sin64[32 - n];
00645                 } else {
00646                     sinv =  sin64[64 -  n];
00647                     cosv = -sin64[n  - 32];
00648                 }
00649 
00650                 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
00651                                                (v1 * sinv) - (v2 * cosv);
00652                 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
00653                                                (v1 * cosv) + (v2 * sinv);
00654             }
00655         }
00656         offset += i;
00657     }
00658 }
00659 
00665 static int decode_channel_transform(WMAProDecodeCtx* s)
00666 {
00667     int i;
00668     /* should never consume more than 1921 bits for the 8 channel case
00669      * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
00670      * + MAX_CHANNELS + MAX_BANDS + 1)
00671      */
00672 
00674     s->num_chgroups = 0;
00675     if (s->num_channels > 1) {
00676         int remaining_channels = s->channels_for_cur_subframe;
00677 
00678         if (get_bits1(&s->gb)) {
00679             av_log_ask_for_sample(s->avctx,
00680                                   "unsupported channel transform bit\n");
00681             return AVERROR_INVALIDDATA;
00682         }
00683 
00684         for (s->num_chgroups = 0; remaining_channels &&
00685              s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
00686             WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
00687             float** channel_data = chgroup->channel_data;
00688             chgroup->num_channels = 0;
00689             chgroup->transform = 0;
00690 
00692             if (remaining_channels > 2) {
00693                 for (i = 0; i < s->channels_for_cur_subframe; i++) {
00694                     int channel_idx = s->channel_indexes_for_cur_subframe[i];
00695                     if (!s->channel[channel_idx].grouped
00696                         && get_bits1(&s->gb)) {
00697                         ++chgroup->num_channels;
00698                         s->channel[channel_idx].grouped = 1;
00699                         *channel_data++ = s->channel[channel_idx].coeffs;
00700                     }
00701                 }
00702             } else {
00703                 chgroup->num_channels = remaining_channels;
00704                 for (i = 0; i < s->channels_for_cur_subframe; i++) {
00705                     int channel_idx = s->channel_indexes_for_cur_subframe[i];
00706                     if (!s->channel[channel_idx].grouped)
00707                         *channel_data++ = s->channel[channel_idx].coeffs;
00708                     s->channel[channel_idx].grouped = 1;
00709                 }
00710             }
00711 
00713             if (chgroup->num_channels == 2) {
00714                 if (get_bits1(&s->gb)) {
00715                     if (get_bits1(&s->gb)) {
00716                         av_log_ask_for_sample(s->avctx,
00717                                               "unsupported channel transform type\n");
00718                     }
00719                 } else {
00720                     chgroup->transform = 1;
00721                     if (s->num_channels == 2) {
00722                         chgroup->decorrelation_matrix[0] =  1.0;
00723                         chgroup->decorrelation_matrix[1] = -1.0;
00724                         chgroup->decorrelation_matrix[2] =  1.0;
00725                         chgroup->decorrelation_matrix[3] =  1.0;
00726                     } else {
00728                         chgroup->decorrelation_matrix[0] =  0.70703125;
00729                         chgroup->decorrelation_matrix[1] = -0.70703125;
00730                         chgroup->decorrelation_matrix[2] =  0.70703125;
00731                         chgroup->decorrelation_matrix[3] =  0.70703125;
00732                     }
00733                 }
00734             } else if (chgroup->num_channels > 2) {
00735                 if (get_bits1(&s->gb)) {
00736                     chgroup->transform = 1;
00737                     if (get_bits1(&s->gb)) {
00738                         decode_decorrelation_matrix(s, chgroup);
00739                     } else {
00741                         if (chgroup->num_channels > 6) {
00742                             av_log_ask_for_sample(s->avctx,
00743                                                   "coupled channels > 6\n");
00744                         } else {
00745                             memcpy(chgroup->decorrelation_matrix,
00746                                    default_decorrelation[chgroup->num_channels],
00747                                    chgroup->num_channels * chgroup->num_channels *
00748                                    sizeof(*chgroup->decorrelation_matrix));
00749                         }
00750                     }
00751                 }
00752             }
00753 
00755             if (chgroup->transform) {
00756                 if (!get_bits1(&s->gb)) {
00757                     int i;
00759                     for (i = 0; i < s->num_bands; i++) {
00760                         chgroup->transform_band[i] = get_bits1(&s->gb);
00761                     }
00762                 } else {
00763                     memset(chgroup->transform_band, 1, s->num_bands);
00764                 }
00765             }
00766             remaining_channels -= chgroup->num_channels;
00767         }
00768     }
00769     return 0;
00770 }
00771 
00778 static int decode_coeffs(WMAProDecodeCtx *s, int c)
00779 {
00780     /* Integers 0..15 as single-precision floats.  The table saves a
00781        costly int to float conversion, and storing the values as
00782        integers allows fast sign-flipping. */
00783     static const uint32_t fval_tab[16] = {
00784         0x00000000, 0x3f800000, 0x40000000, 0x40400000,
00785         0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
00786         0x41000000, 0x41100000, 0x41200000, 0x41300000,
00787         0x41400000, 0x41500000, 0x41600000, 0x41700000,
00788     };
00789     int vlctable;
00790     VLC* vlc;
00791     WMAProChannelCtx* ci = &s->channel[c];
00792     int rl_mode = 0;
00793     int cur_coeff = 0;
00794     int num_zeros = 0;
00795     const uint16_t* run;
00796     const float* level;
00797 
00798     av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
00799 
00800     vlctable = get_bits1(&s->gb);
00801     vlc = &coef_vlc[vlctable];
00802 
00803     if (vlctable) {
00804         run = coef1_run;
00805         level = coef1_level;
00806     } else {
00807         run = coef0_run;
00808         level = coef0_level;
00809     }
00810 
00813     while ((s->transmit_num_vec_coeffs || !rl_mode) &&
00814            (cur_coeff + 3 < ci->num_vec_coeffs)) {
00815         uint32_t vals[4];
00816         int i;
00817         unsigned int idx;
00818 
00819         idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
00820 
00821         if (idx == HUFF_VEC4_SIZE - 1) {
00822             for (i = 0; i < 4; i += 2) {
00823                 idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
00824                 if (idx == HUFF_VEC2_SIZE - 1) {
00825                     uint32_t v0, v1;
00826                     v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
00827                     if (v0 == HUFF_VEC1_SIZE - 1)
00828                         v0 += ff_wma_get_large_val(&s->gb);
00829                     v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
00830                     if (v1 == HUFF_VEC1_SIZE - 1)
00831                         v1 += ff_wma_get_large_val(&s->gb);
00832                     vals[i  ] = av_float2int(v0);
00833                     vals[i+1] = av_float2int(v1);
00834                 } else {
00835                     vals[i]   = fval_tab[symbol_to_vec2[idx] >> 4 ];
00836                     vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
00837                 }
00838             }
00839         } else {
00840             vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12      ];
00841             vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
00842             vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
00843             vals[3] = fval_tab[ symbol_to_vec4[idx]       & 0xF];
00844         }
00845 
00847         for (i = 0; i < 4; i++) {
00848             if (vals[i]) {
00849                 uint32_t sign = get_bits1(&s->gb) - 1;
00850                 AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
00851                 num_zeros = 0;
00852             } else {
00853                 ci->coeffs[cur_coeff] = 0;
00856                 rl_mode |= (++num_zeros > s->subframe_len >> 8);
00857             }
00858             ++cur_coeff;
00859         }
00860     }
00861 
00863     if (cur_coeff < s->subframe_len) {
00864         memset(&ci->coeffs[cur_coeff], 0,
00865                sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
00866         if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
00867                                     level, run, 1, ci->coeffs,
00868                                     cur_coeff, s->subframe_len,
00869                                     s->subframe_len, s->esc_len, 0))
00870             return AVERROR_INVALIDDATA;
00871     }
00872 
00873     return 0;
00874 }
00875 
00881 static int decode_scale_factors(WMAProDecodeCtx* s)
00882 {
00883     int i;
00884 
00889     for (i = 0; i < s->channels_for_cur_subframe; i++) {
00890         int c = s->channel_indexes_for_cur_subframe[i];
00891         int* sf;
00892         int* sf_end;
00893         s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
00894         sf_end = s->channel[c].scale_factors + s->num_bands;
00895 
00901         if (s->channel[c].reuse_sf) {
00902             const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
00903             int b;
00904             for (b = 0; b < s->num_bands; b++)
00905                 s->channel[c].scale_factors[b] =
00906                     s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
00907         }
00908 
00909         if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
00910 
00911             if (!s->channel[c].reuse_sf) {
00912                 int val;
00914                 s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
00915                 val = 45 / s->channel[c].scale_factor_step;
00916                 for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
00917                     val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
00918                     *sf = val;
00919                 }
00920             } else {
00921                 int i;
00923                 for (i = 0; i < s->num_bands; i++) {
00924                     int idx;
00925                     int skip;
00926                     int val;
00927                     int sign;
00928 
00929                     idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
00930 
00931                     if (!idx) {
00932                         uint32_t code = get_bits(&s->gb, 14);
00933                         val  =  code >> 6;
00934                         sign = (code & 1) - 1;
00935                         skip = (code & 0x3f) >> 1;
00936                     } else if (idx == 1) {
00937                         break;
00938                     } else {
00939                         skip = scale_rl_run[idx];
00940                         val  = scale_rl_level[idx];
00941                         sign = get_bits1(&s->gb)-1;
00942                     }
00943 
00944                     i += skip;
00945                     if (i >= s->num_bands) {
00946                         av_log(s->avctx, AV_LOG_ERROR,
00947                                "invalid scale factor coding\n");
00948                         return AVERROR_INVALIDDATA;
00949                     }
00950                     s->channel[c].scale_factors[i] += (val ^ sign) - sign;
00951                 }
00952             }
00954             s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
00955             s->channel[c].table_idx = s->table_idx;
00956             s->channel[c].reuse_sf  = 1;
00957         }
00958 
00960         s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
00961         for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
00962             s->channel[c].max_scale_factor =
00963                 FFMAX(s->channel[c].max_scale_factor, *sf);
00964         }
00965 
00966     }
00967     return 0;
00968 }
00969 
00974 static void inverse_channel_transform(WMAProDecodeCtx *s)
00975 {
00976     int i;
00977 
00978     for (i = 0; i < s->num_chgroups; i++) {
00979         if (s->chgroup[i].transform) {
00980             float data[WMAPRO_MAX_CHANNELS];
00981             const int num_channels = s->chgroup[i].num_channels;
00982             float** ch_data = s->chgroup[i].channel_data;
00983             float** ch_end = ch_data + num_channels;
00984             const int8_t* tb = s->chgroup[i].transform_band;
00985             int16_t* sfb;
00986 
00988             for (sfb = s->cur_sfb_offsets;
00989                  sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
00990                 int y;
00991                 if (*tb++ == 1) {
00993                     for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
00994                         const float* mat = s->chgroup[i].decorrelation_matrix;
00995                         const float* data_end = data + num_channels;
00996                         float* data_ptr = data;
00997                         float** ch;
00998 
00999                         for (ch = ch_data; ch < ch_end; ch++)
01000                             *data_ptr++ = (*ch)[y];
01001 
01002                         for (ch = ch_data; ch < ch_end; ch++) {
01003                             float sum = 0;
01004                             data_ptr = data;
01005                             while (data_ptr < data_end)
01006                                 sum += *data_ptr++ * *mat++;
01007 
01008                             (*ch)[y] = sum;
01009                         }
01010                     }
01011                 } else if (s->num_channels == 2) {
01012                     int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
01013                     s->dsp.vector_fmul_scalar(ch_data[0] + sfb[0],
01014                                               ch_data[0] + sfb[0],
01015                                               181.0 / 128, len);
01016                     s->dsp.vector_fmul_scalar(ch_data[1] + sfb[0],
01017                                               ch_data[1] + sfb[0],
01018                                               181.0 / 128, len);
01019                 }
01020             }
01021         }
01022     }
01023 }
01024 
01029 static void wmapro_window(WMAProDecodeCtx *s)
01030 {
01031     int i;
01032     for (i = 0; i < s->channels_for_cur_subframe; i++) {
01033         int c = s->channel_indexes_for_cur_subframe[i];
01034         float* window;
01035         int winlen = s->channel[c].prev_block_len;
01036         float* start = s->channel[c].coeffs - (winlen >> 1);
01037 
01038         if (s->subframe_len < winlen) {
01039             start += (winlen - s->subframe_len) >> 1;
01040             winlen = s->subframe_len;
01041         }
01042 
01043         window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
01044 
01045         winlen >>= 1;
01046 
01047         s->dsp.vector_fmul_window(start, start, start + winlen,
01048                                   window, winlen);
01049 
01050         s->channel[c].prev_block_len = s->subframe_len;
01051     }
01052 }
01053 
01059 static int decode_subframe(WMAProDecodeCtx *s)
01060 {
01061     int offset = s->samples_per_frame;
01062     int subframe_len = s->samples_per_frame;
01063     int i;
01064     int total_samples   = s->samples_per_frame * s->num_channels;
01065     int transmit_coeffs = 0;
01066     int cur_subwoofer_cutoff;
01067 
01068     s->subframe_offset = get_bits_count(&s->gb);
01069 
01074     for (i = 0; i < s->num_channels; i++) {
01075         s->channel[i].grouped = 0;
01076         if (offset > s->channel[i].decoded_samples) {
01077             offset = s->channel[i].decoded_samples;
01078             subframe_len =
01079                 s->channel[i].subframe_len[s->channel[i].cur_subframe];
01080         }
01081     }
01082 
01083     av_dlog(s->avctx,
01084             "processing subframe with offset %i len %i\n", offset, subframe_len);
01085 
01087     s->channels_for_cur_subframe = 0;
01088     for (i = 0; i < s->num_channels; i++) {
01089         const int cur_subframe = s->channel[i].cur_subframe;
01091         total_samples -= s->channel[i].decoded_samples;
01092 
01094         if (offset == s->channel[i].decoded_samples &&
01095             subframe_len == s->channel[i].subframe_len[cur_subframe]) {
01096             total_samples -= s->channel[i].subframe_len[cur_subframe];
01097             s->channel[i].decoded_samples +=
01098                 s->channel[i].subframe_len[cur_subframe];
01099             s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
01100             ++s->channels_for_cur_subframe;
01101         }
01102     }
01103 
01106     if (!total_samples)
01107         s->parsed_all_subframes = 1;
01108 
01109 
01110     av_dlog(s->avctx, "subframe is part of %i channels\n",
01111             s->channels_for_cur_subframe);
01112 
01114     s->table_idx         = av_log2(s->samples_per_frame/subframe_len);
01115     s->num_bands         = s->num_sfb[s->table_idx];
01116     s->cur_sfb_offsets   = s->sfb_offsets[s->table_idx];
01117     cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
01118 
01120     for (i = 0; i < s->channels_for_cur_subframe; i++) {
01121         int c = s->channel_indexes_for_cur_subframe[i];
01122 
01123         s->channel[c].coeffs = &s->channel[c].out[(s->samples_per_frame >> 1)
01124                                                   + offset];
01125     }
01126 
01127     s->subframe_len = subframe_len;
01128     s->esc_len = av_log2(s->subframe_len - 1) + 1;
01129 
01131     if (get_bits1(&s->gb)) {
01132         int num_fill_bits;
01133         if (!(num_fill_bits = get_bits(&s->gb, 2))) {
01134             int len = get_bits(&s->gb, 4);
01135             num_fill_bits = get_bits(&s->gb, len) + 1;
01136         }
01137 
01138         if (num_fill_bits >= 0) {
01139             if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
01140                 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
01141                 return AVERROR_INVALIDDATA;
01142             }
01143 
01144             skip_bits_long(&s->gb, num_fill_bits);
01145         }
01146     }
01147 
01149     if (get_bits1(&s->gb)) {
01150         av_log_ask_for_sample(s->avctx, "reserved bit set\n");
01151         return AVERROR_INVALIDDATA;
01152     }
01153 
01154 
01155     if (decode_channel_transform(s) < 0)
01156         return AVERROR_INVALIDDATA;
01157 
01158 
01159     for (i = 0; i < s->channels_for_cur_subframe; i++) {
01160         int c = s->channel_indexes_for_cur_subframe[i];
01161         if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
01162             transmit_coeffs = 1;
01163     }
01164 
01165     if (transmit_coeffs) {
01166         int step;
01167         int quant_step = 90 * s->bits_per_sample >> 4;
01168 
01170         if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
01171             int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
01172             for (i = 0; i < s->channels_for_cur_subframe; i++) {
01173                 int c = s->channel_indexes_for_cur_subframe[i];
01174                 int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
01175                 if (num_vec_coeffs > WMAPRO_BLOCK_MAX_SIZE) {
01176                     av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
01177                     return AVERROR_INVALIDDATA;
01178                 }
01179                 s->channel[c].num_vec_coeffs = num_vec_coeffs;
01180             }
01181         } else {
01182             for (i = 0; i < s->channels_for_cur_subframe; i++) {
01183                 int c = s->channel_indexes_for_cur_subframe[i];
01184                 s->channel[c].num_vec_coeffs = s->subframe_len;
01185             }
01186         }
01188         step = get_sbits(&s->gb, 6);
01189         quant_step += step;
01190         if (step == -32 || step == 31) {
01191             const int sign = (step == 31) - 1;
01192             int quant = 0;
01193             while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
01194                    (step = get_bits(&s->gb, 5)) == 31) {
01195                 quant += 31;
01196             }
01197             quant_step += ((quant + step) ^ sign) - sign;
01198         }
01199         if (quant_step < 0) {
01200             av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
01201         }
01202 
01205         if (s->channels_for_cur_subframe == 1) {
01206             s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
01207         } else {
01208             int modifier_len = get_bits(&s->gb, 3);
01209             for (i = 0; i < s->channels_for_cur_subframe; i++) {
01210                 int c = s->channel_indexes_for_cur_subframe[i];
01211                 s->channel[c].quant_step = quant_step;
01212                 if (get_bits1(&s->gb)) {
01213                     if (modifier_len) {
01214                         s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
01215                     } else
01216                         ++s->channel[c].quant_step;
01217                 }
01218             }
01219         }
01220 
01222         if (decode_scale_factors(s) < 0)
01223             return AVERROR_INVALIDDATA;
01224     }
01225 
01226     av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
01227             get_bits_count(&s->gb) - s->subframe_offset);
01228 
01230     for (i = 0; i < s->channels_for_cur_subframe; i++) {
01231         int c = s->channel_indexes_for_cur_subframe[i];
01232         if (s->channel[c].transmit_coefs &&
01233             get_bits_count(&s->gb) < s->num_saved_bits) {
01234             decode_coeffs(s, c);
01235         } else
01236             memset(s->channel[c].coeffs, 0,
01237                    sizeof(*s->channel[c].coeffs) * subframe_len);
01238     }
01239 
01240     av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
01241             get_bits_count(&s->gb) - s->subframe_offset);
01242 
01243     if (transmit_coeffs) {
01244         FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
01246         inverse_channel_transform(s);
01247         for (i = 0; i < s->channels_for_cur_subframe; i++) {
01248             int c = s->channel_indexes_for_cur_subframe[i];
01249             const int* sf = s->channel[c].scale_factors;
01250             int b;
01251 
01252             if (c == s->lfe_channel)
01253                 memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
01254                        (subframe_len - cur_subwoofer_cutoff));
01255 
01257             for (b = 0; b < s->num_bands; b++) {
01258                 const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
01259                 const int exp = s->channel[c].quant_step -
01260                             (s->channel[c].max_scale_factor - *sf++) *
01261                             s->channel[c].scale_factor_step;
01262                 const float quant = pow(10.0, exp / 20.0);
01263                 int start = s->cur_sfb_offsets[b];
01264                 s->dsp.vector_fmul_scalar(s->tmp + start,
01265                                           s->channel[c].coeffs + start,
01266                                           quant, end - start);
01267             }
01268 
01270             mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
01271         }
01272     }
01273 
01275     wmapro_window(s);
01276 
01278     for (i = 0; i < s->channels_for_cur_subframe; i++) {
01279         int c = s->channel_indexes_for_cur_subframe[i];
01280         if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
01281             av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
01282             return AVERROR_INVALIDDATA;
01283         }
01284         ++s->channel[c].cur_subframe;
01285     }
01286 
01287     return 0;
01288 }
01289 
01296 static int decode_frame(WMAProDecodeCtx *s, int *got_frame_ptr)
01297 {
01298     AVCodecContext *avctx = s->avctx;
01299     GetBitContext* gb = &s->gb;
01300     int more_frames = 0;
01301     int len = 0;
01302     int i, ret;
01303     const float *out_ptr[WMAPRO_MAX_CHANNELS];
01304     float *samples;
01305 
01307     if (s->len_prefix)
01308         len = get_bits(gb, s->log2_frame_size);
01309 
01310     av_dlog(s->avctx, "decoding frame with length %x\n", len);
01311 
01313     if (decode_tilehdr(s)) {
01314         s->packet_loss = 1;
01315         return 0;
01316     }
01317 
01319     if (s->num_channels > 1 && get_bits1(gb)) {
01320         if (get_bits1(gb)) {
01321             for (i = 0; i < s->num_channels * s->num_channels; i++)
01322                 skip_bits(gb, 4);
01323         }
01324     }
01325 
01327     if (s->dynamic_range_compression) {
01328         s->drc_gain = get_bits(gb, 8);
01329         av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
01330     }
01331 
01334     if (get_bits1(gb)) {
01335         int av_unused skip;
01336 
01338         if (get_bits1(gb)) {
01339             skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
01340             av_dlog(s->avctx, "start skip: %i\n", skip);
01341         }
01342 
01344         if (get_bits1(gb)) {
01345             skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
01346             av_dlog(s->avctx, "end skip: %i\n", skip);
01347         }
01348 
01349     }
01350 
01351     av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
01352             get_bits_count(gb) - s->frame_offset);
01353 
01355     s->parsed_all_subframes = 0;
01356     for (i = 0; i < s->num_channels; i++) {
01357         s->channel[i].decoded_samples = 0;
01358         s->channel[i].cur_subframe    = 0;
01359         s->channel[i].reuse_sf        = 0;
01360     }
01361 
01363     while (!s->parsed_all_subframes) {
01364         if (decode_subframe(s) < 0) {
01365             s->packet_loss = 1;
01366             return 0;
01367         }
01368     }
01369 
01370     /* get output buffer */
01371     s->frame.nb_samples = s->samples_per_frame;
01372     if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
01373         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
01374         s->packet_loss = 1;
01375         return 0;
01376     }
01377     samples = (float *)s->frame.data[0];
01378 
01380     for (i = 0; i < s->num_channels; i++)
01381         out_ptr[i] = s->channel[i].out;
01382     s->fmt_conv.float_interleave(samples, out_ptr, s->samples_per_frame,
01383                                  s->num_channels);
01384 
01385     for (i = 0; i < s->num_channels; i++) {
01387         memcpy(&s->channel[i].out[0],
01388                &s->channel[i].out[s->samples_per_frame],
01389                s->samples_per_frame * sizeof(*s->channel[i].out) >> 1);
01390     }
01391 
01392     if (s->skip_frame) {
01393         s->skip_frame = 0;
01394         *got_frame_ptr = 0;
01395     } else {
01396         *got_frame_ptr = 1;
01397     }
01398 
01399     if (s->len_prefix) {
01400         if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
01402             av_log(s->avctx, AV_LOG_ERROR,
01403                    "frame[%i] would have to skip %i bits\n", s->frame_num,
01404                    len - (get_bits_count(gb) - s->frame_offset) - 1);
01405             s->packet_loss = 1;
01406             return 0;
01407         }
01408 
01410         skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
01411     } else {
01412         while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
01413         }
01414     }
01415 
01417     more_frames = get_bits1(gb);
01418 
01419     ++s->frame_num;
01420     return more_frames;
01421 }
01422 
01429 static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
01430 {
01431     return s->buf_bit_size - get_bits_count(gb);
01432 }
01433 
01441 static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
01442                       int append)
01443 {
01444     int buflen;
01445 
01450     if (!append) {
01451         s->frame_offset = get_bits_count(gb) & 7;
01452         s->num_saved_bits = s->frame_offset;
01453         init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
01454     }
01455 
01456     buflen = (s->num_saved_bits + len + 8) >> 3;
01457 
01458     if (len <= 0 || buflen > MAX_FRAMESIZE) {
01459         av_log_ask_for_sample(s->avctx, "input buffer too small\n");
01460         s->packet_loss = 1;
01461         return;
01462     }
01463 
01464     s->num_saved_bits += len;
01465     if (!append) {
01466         avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
01467                      s->num_saved_bits);
01468     } else {
01469         int align = 8 - (get_bits_count(gb) & 7);
01470         align = FFMIN(align, len);
01471         put_bits(&s->pb, align, get_bits(gb, align));
01472         len -= align;
01473         avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
01474     }
01475     skip_bits_long(gb, len);
01476 
01477     {
01478         PutBitContext tmp = s->pb;
01479         flush_put_bits(&tmp);
01480     }
01481 
01482     init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
01483     skip_bits(&s->gb, s->frame_offset);
01484 }
01485 
01494 static int decode_packet(AVCodecContext *avctx, void *data,
01495                          int *got_frame_ptr, AVPacket* avpkt)
01496 {
01497     WMAProDecodeCtx *s = avctx->priv_data;
01498     GetBitContext* gb  = &s->pgb;
01499     const uint8_t* buf = avpkt->data;
01500     int buf_size       = avpkt->size;
01501     int num_bits_prev_frame;
01502     int packet_sequence_number;
01503 
01504     *got_frame_ptr = 0;
01505 
01506     if (s->packet_done || s->packet_loss) {
01507         s->packet_done = 0;
01508 
01510         if (buf_size < avctx->block_align)
01511             return 0;
01512 
01513         s->next_packet_start = buf_size - avctx->block_align;
01514         buf_size = avctx->block_align;
01515         s->buf_bit_size = buf_size << 3;
01516 
01518         init_get_bits(gb, buf, s->buf_bit_size);
01519         packet_sequence_number = get_bits(gb, 4);
01520         skip_bits(gb, 2);
01521 
01523         num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
01524         av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
01525                 num_bits_prev_frame);
01526 
01528         if (!s->packet_loss &&
01529             ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
01530             s->packet_loss = 1;
01531             av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
01532                    s->packet_sequence_number, packet_sequence_number);
01533         }
01534         s->packet_sequence_number = packet_sequence_number;
01535 
01536         if (num_bits_prev_frame > 0) {
01537             int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
01538             if (num_bits_prev_frame >= remaining_packet_bits) {
01539                 num_bits_prev_frame = remaining_packet_bits;
01540                 s->packet_done = 1;
01541             }
01542 
01545             save_bits(s, gb, num_bits_prev_frame, 1);
01546             av_dlog(avctx, "accumulated %x bits of frame data\n",
01547                     s->num_saved_bits - s->frame_offset);
01548 
01550             if (!s->packet_loss)
01551                 decode_frame(s, got_frame_ptr);
01552         } else if (s->num_saved_bits - s->frame_offset) {
01553             av_dlog(avctx, "ignoring %x previously saved bits\n",
01554                     s->num_saved_bits - s->frame_offset);
01555         }
01556 
01557         if (s->packet_loss) {
01561             s->num_saved_bits = 0;
01562             s->packet_loss = 0;
01563         }
01564 
01565     } else {
01566         int frame_size;
01567         s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
01568         init_get_bits(gb, avpkt->data, s->buf_bit_size);
01569         skip_bits(gb, s->packet_offset);
01570         if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
01571             (frame_size = show_bits(gb, s->log2_frame_size)) &&
01572             frame_size <= remaining_bits(s, gb)) {
01573             save_bits(s, gb, frame_size, 0);
01574             s->packet_done = !decode_frame(s, got_frame_ptr);
01575         } else if (!s->len_prefix
01576                    && s->num_saved_bits > get_bits_count(&s->gb)) {
01584             s->packet_done = !decode_frame(s, got_frame_ptr);
01585         } else
01586             s->packet_done = 1;
01587     }
01588 
01589     if (s->packet_done && !s->packet_loss &&
01590         remaining_bits(s, gb) > 0) {
01593         save_bits(s, gb, remaining_bits(s, gb), 0);
01594     }
01595 
01596     s->packet_offset = get_bits_count(gb) & 7;
01597     if (s->packet_loss)
01598         return AVERROR_INVALIDDATA;
01599 
01600     if (*got_frame_ptr)
01601         *(AVFrame *)data = s->frame;
01602 
01603     return get_bits_count(gb) >> 3;
01604 }
01605 
01610 static void flush(AVCodecContext *avctx)
01611 {
01612     WMAProDecodeCtx *s = avctx->priv_data;
01613     int i;
01616     for (i = 0; i < s->num_channels; i++)
01617         memset(s->channel[i].out, 0, s->samples_per_frame *
01618                sizeof(*s->channel[i].out));
01619     s->packet_loss = 1;
01620 }
01621 
01622 
01626 AVCodec ff_wmapro_decoder = {
01627     .name           = "wmapro",
01628     .type           = AVMEDIA_TYPE_AUDIO,
01629     .id             = CODEC_ID_WMAPRO,
01630     .priv_data_size = sizeof(WMAProDecodeCtx),
01631     .init           = decode_init,
01632     .close          = decode_end,
01633     .decode         = decode_packet,
01634     .capabilities   = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
01635     .flush= flush,
01636     .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
01637 };
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