2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 static int noise(AVBitStreamFilterContext
*bsfc
, AVCodecContext
*avctx
, const char *args
,
25 uint8_t **poutbuf
, int *poutbuf_size
,
26 const uint8_t *buf
, int buf_size
, int keyframe
){
27 int amount
= args
? atoi(args
) : 10000;
28 unsigned int *state
= bsfc
->priv_data
;
31 *poutbuf
= av_malloc(buf_size
+ FF_INPUT_BUFFER_PADDING_SIZE
);
33 memcpy(*poutbuf
, buf
, buf_size
+ FF_INPUT_BUFFER_PADDING_SIZE
);
34 for(i
=0; i
<buf_size
; i
++){
35 (*state
) += (*poutbuf
)[i
] + 1;
36 if(*state
% amount
== 0)
37 (*poutbuf
)[i
] = *state
;
42 AVBitStreamFilter noise_bsf
={