X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Frangecoder.h;h=ad9c81faa44f98fbe4fb281c51dd01f61e312dc4;hb=de16f08e48a2e0dbd7311882d97fe379535c5a48;hp=4726afb56e4b49e9edc8b4ad9088d39570f04926;hpb=5b21bdabe43611385d1d55a21d5b1f607b133d29;p=ffmpeg diff --git a/libavcodec/rangecoder.h b/libavcodec/rangecoder.h index 4726afb56e4..ad9c81faa44 100644 --- a/libavcodec/rangecoder.h +++ b/libavcodec/rangecoder.h @@ -2,140 +2,146 @@ * Range coder * Copyright (c) 2004 Michael Niedermayer * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** - * @file rangecoder.h + * @file * Range coder. */ -#ifndef FFMPEG_RANGECODER_H -#define FFMPEG_RANGECODER_H +#ifndef AVCODEC_RANGECODER_H +#define AVCODEC_RANGECODER_H #include #include -#include "common.h" -typedef struct RangeCoder{ +#include "libavutil/common.h" + +typedef struct RangeCoder { int low; int range; int outstanding_count; int outstanding_byte; uint8_t zero_state[256]; - uint8_t one_state[256]; + uint8_t one_state[256]; uint8_t *bytestream_start; uint8_t *bytestream; uint8_t *bytestream_end; -}RangeCoder; +} RangeCoder; void ff_init_range_encoder(RangeCoder *c, uint8_t *buf, int buf_size); void ff_init_range_decoder(RangeCoder *c, const uint8_t *buf, int buf_size); int ff_rac_terminate(RangeCoder *c); void ff_build_rac_states(RangeCoder *c, int factor, int max_p); -static inline void renorm_encoder(RangeCoder *c){ - //FIXME optimize - while(c->range < 0x100){ - if(c->outstanding_byte < 0){ - c->outstanding_byte= c->low>>8; - }else if(c->low <= 0xFF00){ +static inline void renorm_encoder(RangeCoder *c) +{ + // FIXME: optimize + while (c->range < 0x100) { + if (c->outstanding_byte < 0) { + c->outstanding_byte = c->low >> 8; + } else if (c->low <= 0xFF00) { *c->bytestream++ = c->outstanding_byte; - for(;c->outstanding_count; c->outstanding_count--) + for (; c->outstanding_count; c->outstanding_count--) *c->bytestream++ = 0xFF; - c->outstanding_byte= c->low>>8; - }else if(c->low >= 0x10000){ + c->outstanding_byte = c->low >> 8; + } else if (c->low >= 0x10000) { *c->bytestream++ = c->outstanding_byte + 1; - for(;c->outstanding_count; c->outstanding_count--) + for (; c->outstanding_count; c->outstanding_count--) *c->bytestream++ = 0x00; - c->outstanding_byte= (c->low>>8) & 0xFF; - }else{ + c->outstanding_byte = (c->low >> 8) & 0xFF; + } else { c->outstanding_count++; } - c->low = (c->low & 0xFF)<<8; + c->low = (c->low & 0xFF) << 8; c->range <<= 8; } } -static inline int get_rac_count(RangeCoder *c){ - int x= c->bytestream - c->bytestream_start + c->outstanding_count; - if(c->outstanding_byte >= 0) +static inline int get_rac_count(RangeCoder *c) +{ + int x = c->bytestream - c->bytestream_start + c->outstanding_count; + if (c->outstanding_byte >= 0) x++; - return 8*x - av_log2(c->range); + return 8 * x - av_log2(c->range); } -static inline void put_rac(RangeCoder *c, uint8_t * const state, int bit){ - int range1= (c->range * (*state)) >> 8; +static inline void put_rac(RangeCoder *c, uint8_t *const state, int bit) +{ + int range1 = (c->range * (*state)) >> 8; assert(*state); assert(range1 < c->range); assert(range1 > 0); - if(!bit){ + if (!bit) { c->range -= range1; - *state= c->zero_state[*state]; - }else{ - c->low += c->range - range1; + *state = c->zero_state[*state]; + } else { + c->low += c->range - range1; c->range = range1; - *state= c->one_state[*state]; + *state = c->one_state[*state]; } renorm_encoder(c); } -static inline void refill(RangeCoder *c){ - if(c->range < 0x100){ +static inline void refill(RangeCoder *c) +{ + if (c->range < 0x100) { c->range <<= 8; - c->low <<= 8; - if(c->bytestream < c->bytestream_end) - c->low+= c->bytestream[0]; + c->low <<= 8; + if (c->bytestream < c->bytestream_end) + c->low += c->bytestream[0]; c->bytestream++; } } -static inline int get_rac(RangeCoder *c, uint8_t * const state){ - int range1= (c->range * (*state)) >> 8; +static inline int get_rac(RangeCoder *c, uint8_t *const state) +{ + int range1 = (c->range * (*state)) >> 8; int av_unused one_mask; c->range -= range1; #if 1 - if(c->low < c->range){ - *state= c->zero_state[*state]; + if (c->low < c->range) { + *state = c->zero_state[*state]; refill(c); return 0; - }else{ - c->low -= c->range; - *state= c->one_state[*state]; + } else { + c->low -= c->range; + *state = c->one_state[*state]; c->range = range1; refill(c); return 1; } #else - one_mask= (c->range - c->low-1)>>31; + one_mask = (c->range - c->low - 1) >> 31; - c->low -= c->range & one_mask; + c->low -= c->range & one_mask; c->range += (range1 - c->range) & one_mask; - *state= c->zero_state[(*state) + (256&one_mask)]; + *state = c->zero_state[(*state) + (256 & one_mask)]; refill(c); - return one_mask&1; + return one_mask & 1; #endif } -#endif /* FFMPEG_RANGECODER_H */ +#endif /* AVCODEC_RANGECODER_H */