/* * 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 <stdlib.h> #include <string.h> #include "avcodec.h" #include "libavutil/mem.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; if(amount <= 0) return AVERROR(EINVAL); *poutbuf= av_malloc(buf_size + FF_INPUT_BUFFER_PADDING_SIZE); if (!*poutbuf) return AVERROR(ENOMEM); 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={ .name = "noise", .priv_data_size = sizeof(int), .filter = noise, };