/*
  * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
  *

  * This file is part of FFmpeg.

  *

  * FFmpeg 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 2.1 of the License, or (at your option) any later version.
  *

  * FFmpeg 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 FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #ifndef AVRESAMPLE_DITHER_H
 #define AVRESAMPLE_DITHER_H
 
 #include "avresample.h"
 #include "audio_data.h"
 
 typedef struct DitherContext DitherContext;
 
 typedef struct DitherDSPContext {
     /**
      * Convert samples from flt to s16 with added dither noise.
      *
      * @param dst    destination float array, range -0.5 to 0.5
      * @param src    source int array, range INT_MIN to INT_MAX.
      * @param dither float dither noise array
      * @param len    number of samples
      */
     void (*quantize)(int16_t *dst, const float *src, float *dither, int len);
 
     int ptr_align;      ///< src and dst constraits for quantize()
     int samples_align;  ///< len constraits for quantize()
 
     /**
      * Convert dither noise from int to float with triangular distribution.
      *
      * @param dst  destination float array, range -0.5 to 0.5
      *             constraints: 32-byte aligned
      * @param src0 source int array, range INT_MIN to INT_MAX.
      *             the array size is len * 2
      *             constraints: 32-byte aligned
      * @param len  number of output noise samples
      *             constraints: multiple of 16
      */
     void (*dither_int_to_float)(float *dst, int *src0, int len);
 } DitherDSPContext;
 
 /**
  * Allocate and initialize a DitherContext.
  *
  * The parameters in the AVAudioResampleContext are used to initialize the
  * DitherContext.
  *
  * @param avr  AVAudioResampleContext
  * @return     newly-allocated DitherContext
  */
 DitherContext *ff_dither_alloc(AVAudioResampleContext *avr,
                                enum AVSampleFormat out_fmt,
                                enum AVSampleFormat in_fmt,

                                int channels, int sample_rate, int apply_map);

 
 /**
  * Free a DitherContext.
  *
  * @param c  DitherContext
  */
 void ff_dither_free(DitherContext **c);
 
 /**
  * Convert audio sample format with dithering.
  *
  * @param c    DitherContext
  * @param dst  destination audio data
  * @param src  source audio data
  * @return     0 if ok, negative AVERROR code on failure
  */
 int ff_convert_dither(DitherContext *c, AudioData *dst, AudioData *src);
 

 /* arch-specific initialization functions */
 
 void ff_dither_init_x86(DitherDSPContext *ddsp,
                         enum AVResampleDitherMethod method);
 

 #endif /* AVRESAMPLE_DITHER_H */