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Diffstat (limited to 'contrib/ffmpeg/libavcodec/rangecoder.c')
| -rw-r--r-- | contrib/ffmpeg/libavcodec/rangecoder.c | 153 |
1 files changed, 0 insertions, 153 deletions
diff --git a/contrib/ffmpeg/libavcodec/rangecoder.c b/contrib/ffmpeg/libavcodec/rangecoder.c deleted file mode 100644 index fcd564ace..000000000 --- a/contrib/ffmpeg/libavcodec/rangecoder.c +++ /dev/null @@ -1,153 +0,0 @@ -/* - * Range coder - * Copyright (c) 2004 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 - * - */ - -/** - * @file rangecoder.c - * Range coder. - * based upon - * "Range encoding: an algorithm for removing redundancy from a digitised - * message. - * G. N. N. Martin Presented in March 1979 to the Video & - * Data Recording Conference, - * IBM UK Scientific Center held in Southampton July 24-27 1979." - * - */ - -#include <string.h> - -#include "avcodec.h" -#include "common.h" -#include "rangecoder.h" - - -void ff_init_range_encoder(RangeCoder *c, uint8_t *buf, int buf_size){ - c->bytestream_start= - c->bytestream= buf; - c->bytestream_end= buf + buf_size; - - c->low= 0; - c->range= 0xFF00; - c->outstanding_count= 0; - c->outstanding_byte= -1; -} - -void ff_init_range_decoder(RangeCoder *c, const uint8_t *buf, int buf_size){ - /* cast to avoid compiler warning */ - ff_init_range_encoder(c, (uint8_t *) buf, buf_size); - - c->low =(*c->bytestream++)<<8; - c->low+= *c->bytestream++; -} - -void ff_build_rac_states(RangeCoder *c, int factor, int max_p){ - const int64_t one= 1LL<<32; - int64_t p; - int last_p8, p8, i; - - memset(c->zero_state, 0, sizeof(c->zero_state)); - memset(c-> one_state, 0, sizeof(c-> one_state)); - - last_p8= 0; - p= one/2; - for(i=0; i<128; i++){ - p8= (256*p + one/2) >> 32; //FIXME try without the one - if(p8 <= last_p8) p8= last_p8+1; - if(last_p8 && last_p8<256 && p8<=max_p) - c->one_state[last_p8]= p8; - - p+= ((one-p)*factor + one/2) >> 32; - last_p8= p8; - } - - for(i=256-max_p; i<=max_p; i++){ - if(c->one_state[i]) - continue; - - p= (i*one + 128) >> 8; - p+= ((one-p)*factor + one/2) >> 32; - p8= (256*p + one/2) >> 32; //FIXME try without the one - if(p8 <= i) p8= i+1; - if(p8 > max_p) p8= max_p; - c->one_state[ i]= p8; - } - - for(i=1; i<255; i++) - c->zero_state[i]= 256-c->one_state[256-i]; -} - -/** - * - * @return the number of bytes written - */ -int ff_rac_terminate(RangeCoder *c){ - c->range=0xFF; - c->low +=0xFF; - renorm_encoder(c); - c->range=0xFF; - renorm_encoder(c); - - assert(c->low == 0); - assert(c->range >= 0x100); - - return c->bytestream - c->bytestream_start; -} - -#if 0 //selftest -#define SIZE 10240 -int main(){ - RangeCoder c; - uint8_t b[9*SIZE]; - uint8_t r[9*SIZE]; - int i; - uint8_t state[10]= {0}; - - ff_init_range_encoder(&c, b, SIZE); - ff_build_rac_states(&c, 0.05*(1LL<<32), 128+64+32+16); - - memset(state, 128, sizeof(state)); - - for(i=0; i<SIZE; i++){ - r[i]= random()%7; - } - - for(i=0; i<SIZE; i++){ -START_TIMER - put_rac(&c, state, r[i]&1); -STOP_TIMER("put_rac") - } - - ff_put_rac_terminate(&c); - - ff_init_range_decoder(&c, b, SIZE); - - memset(state, 128, sizeof(state)); - - for(i=0; i<SIZE; i++){ -START_TIMER - if( (r[i]&1) != get_rac(&c, state) ) - av_log(NULL, AV_LOG_DEBUG, "rac failure at %d\n", i); -STOP_TIMER("get_rac") - } - - return 0; -} -#endif |