/*
  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
  *
  * 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
  */
 
 #include "avcodec.h"
 
 
 static int noise(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
                      uint8_t **poutbuf, int *poutbuf_size,
                      const uint8_t *buf, int buf_size, int keyframe){
     unsigned int *state= bsfc->priv_data;

     int amount= args ? atoi(args) : (*state % 10001+1);

     int i;
 
     *poutbuf= av_malloc(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
 
     memcpy(*poutbuf, buf, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
     for(i=0; i<buf_size; i++){
         (*state) += (*poutbuf)[i] + 1;
         if(*state % amount == 0)
             (*poutbuf)[i] = *state;
     }
     return 1;
 }
 

 AVBitStreamFilter ff_noise_bsf={

     "noise",
     sizeof(int),
     noise,
 };