vbr.h

00001 /* Copyright (C) 2002 Jean-Marc Valin */
00002 /**
00003    @file vbr.h
00004    @brief Variable Bit-Rate (VBR) related routines
00005 */
00006 /*
00007    Redistribution and use in source and binary forms, with or without
00008    modification, are permitted provided that the following conditions
00009    are met:
00010    
00011    - Redistributions of source code must retain the above copyright
00012    notice, this list of conditions and the following disclaimer.
00013    
00014    - Redistributions in binary form must reproduce the above copyright
00015    notice, this list of conditions and the following disclaimer in the
00016    documentation and/or other materials provided with the distribution.
00017    
00018    - Neither the name of the Xiph.org Foundation nor the names of its
00019    contributors may be used to endorse or promote products derived from
00020    this software without specific prior written permission.
00021    
00022    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00023    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00024    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
00025    A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
00026    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00027    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
00028    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
00029    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
00030    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
00031    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00032    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00033 
00034 */
00035 
00036 
00037 #ifndef VBR_H
00038 #define VBR_H
00039 
00040 #include "misc.h"
00041 
00042 #define VBR_MEMORY_SIZE 5
00043 
00044 extern const float vbr_nb_thresh[9][11];
00045 extern const float vbr_hb_thresh[5][11];
00046 extern const float vbr_uhb_thresh[2][11];
00047 
00048 /** VBR state. */
00049 typedef struct VBRState {
00050    float energy_alpha;
00051    float average_energy;
00052    float last_energy;
00053    float last_log_energy[VBR_MEMORY_SIZE];
00054    float accum_sum;
00055    float last_pitch_coef;
00056    float soft_pitch;
00057    float last_quality;
00058    float noise_level;
00059    float noise_accum;
00060    float noise_accum_count;
00061    int   consec_noise;
00062 } VBRState;
00063 
00064 void vbr_init(VBRState *vbr);
00065 
00066 float vbr_analysis(VBRState *vbr, spx_word16_t *sig, int len, int pitch, float pitch_coef);
00067 
00068 void vbr_destroy(VBRState *vbr);
00069 
00070 #endif