yading@10: /*
yading@10:  * exp golomb vlc stuff
yading@10:  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
yading@10:  * Copyright (c) 2004 Alex Beregszaszi
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * @brief
yading@10:  *     exp golomb vlc stuff
yading@10:  * @author Michael Niedermayer <michaelni@gmx.at> and Alex Beregszaszi
yading@10:  */
yading@10: 
yading@10: #ifndef AVCODEC_GOLOMB_H
yading@10: #define AVCODEC_GOLOMB_H
yading@10: 
yading@10: #include <stdint.h>
yading@10: #include "get_bits.h"
yading@10: #include "put_bits.h"
yading@10: 
yading@10: #define INVALID_VLC           0x80000000
yading@10: 
yading@10: extern const uint8_t ff_golomb_vlc_len[512];
yading@10: extern const uint8_t ff_ue_golomb_vlc_code[512];
yading@10: extern const  int8_t ff_se_golomb_vlc_code[512];
yading@10: extern const uint8_t ff_ue_golomb_len[256];
yading@10: 
yading@10: extern const uint8_t ff_interleaved_golomb_vlc_len[256];
yading@10: extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
yading@10: extern const  int8_t ff_interleaved_se_golomb_vlc_code[256];
yading@10: extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
yading@10: 
yading@10: 
yading@10:  /**
yading@10:  * read unsigned exp golomb code.
yading@10:  */
yading@10: static inline int get_ue_golomb(GetBitContext *gb){
yading@10:     unsigned int buf;
yading@10:     int log;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     if(buf >= (1<<27)){
yading@10:         buf >>= 32 - 9;
yading@10:         LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return ff_ue_golomb_vlc_code[buf];
yading@10:     }else{
yading@10:         log= 2*av_log2(buf) - 31;
yading@10:         LAST_SKIP_BITS(re, gb, 32 - log);
yading@10:         CLOSE_READER(re, gb);
yading@10:         if (CONFIG_FTRAPV && log < 0) {
yading@10:             av_log(0, AV_LOG_ERROR, "Invalid UE golomb code\n");
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:         buf>>= log;
yading@10:         buf--;
yading@10: 
yading@10:         return buf;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
yading@10:  */
yading@10: static inline unsigned get_ue_golomb_long(GetBitContext *gb)
yading@10: {
yading@10:     unsigned buf, log;
yading@10: 
yading@10:     buf = show_bits_long(gb, 32);
yading@10:     log = 31 - av_log2(buf);
yading@10:     skip_bits_long(gb, log);
yading@10: 
yading@10:     return get_bits_long(gb, log + 1) - 1;
yading@10: }
yading@10: 
yading@10:  /**
yading@10:  * read unsigned exp golomb code, constraint to a max of 31.
yading@10:  * the return value is undefined if the stored value exceeds 31.
yading@10:  */
yading@10: static inline int get_ue_golomb_31(GetBitContext *gb){
yading@10:     unsigned int buf;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     buf >>= 32 - 9;
yading@10:     LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
yading@10:     CLOSE_READER(re, gb);
yading@10: 
yading@10:     return ff_ue_golomb_vlc_code[buf];
yading@10: }
yading@10: 
yading@10: static inline unsigned svq3_get_ue_golomb(GetBitContext *gb)
yading@10: {
yading@10:     uint32_t buf;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     if(buf&0xAA800000){
yading@10:         buf >>= 32 - 8;
yading@10:         LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return ff_interleaved_ue_golomb_vlc_code[buf];
yading@10:     }else{
yading@10:         unsigned ret = 1;
yading@10: 
yading@10:         do {
yading@10:             buf >>= 32 - 8;
yading@10:             LAST_SKIP_BITS(re, gb, FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
yading@10: 
yading@10:             if (ff_interleaved_golomb_vlc_len[buf] != 9){
yading@10:                 ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
yading@10:                 ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
yading@10:                 break;
yading@10:             }
yading@10:             ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
yading@10:             UPDATE_CACHE(re, gb);
yading@10:             buf = GET_CACHE(re, gb);
yading@10:         } while (ret<0x8000000U && HAVE_BITS_REMAINING(re, gb));
yading@10: 
yading@10:         CLOSE_READER(re, gb);
yading@10:         return ret - 1;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read unsigned truncated exp golomb code.
yading@10:  */
yading@10: static inline int get_te0_golomb(GetBitContext *gb, int range){
yading@10:     av_assert2(range >= 1);
yading@10: 
yading@10:     if(range==1)      return 0;
yading@10:     else if(range==2) return get_bits1(gb)^1;
yading@10:     else              return get_ue_golomb(gb);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read unsigned truncated exp golomb code.
yading@10:  */
yading@10: static inline int get_te_golomb(GetBitContext *gb, int range){
yading@10:     av_assert2(range >= 1);
yading@10: 
yading@10:     if(range==2) return get_bits1(gb)^1;
yading@10:     else         return get_ue_golomb(gb);
yading@10: }
yading@10: 
yading@10: 
yading@10: /**
yading@10:  * read signed exp golomb code.
yading@10:  */
yading@10: static inline int get_se_golomb(GetBitContext *gb){
yading@10:     unsigned int buf;
yading@10:     int log;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     if(buf >= (1<<27)){
yading@10:         buf >>= 32 - 9;
yading@10:         LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return ff_se_golomb_vlc_code[buf];
yading@10:     }else{
yading@10:         log = av_log2(buf);
yading@10:         LAST_SKIP_BITS(re, gb, 31 - log);
yading@10:         UPDATE_CACHE(re, gb);
yading@10:         buf = GET_CACHE(re, gb);
yading@10: 
yading@10:         buf>>= log;
yading@10: 
yading@10:         LAST_SKIP_BITS(re, gb, 32 - log);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         if(buf&1) buf= -(buf>>1);
yading@10:         else      buf=  (buf>>1);
yading@10: 
yading@10:         return buf;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static inline int svq3_get_se_golomb(GetBitContext *gb){
yading@10:     unsigned int buf;
yading@10:     int log;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     if(buf&0xAA800000){
yading@10:         buf >>= 32 - 8;
yading@10:         LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return ff_interleaved_se_golomb_vlc_code[buf];
yading@10:     }else{
yading@10:         LAST_SKIP_BITS(re, gb, 8);
yading@10:         UPDATE_CACHE(re, gb);
yading@10:         buf |= 1 | (GET_CACHE(re, gb) >> 8);
yading@10: 
yading@10:         if((buf & 0xAAAAAAAA) == 0)
yading@10:             return INVALID_VLC;
yading@10: 
yading@10:         for(log=31; (buf & 0x80000000) == 0; log--){
yading@10:             buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
yading@10:         }
yading@10: 
yading@10:         LAST_SKIP_BITS(re, gb, 63 - 2*log - 8);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static inline int dirac_get_se_golomb(GetBitContext *gb){
yading@10:     uint32_t buf;
yading@10:     uint32_t ret;
yading@10: 
yading@10:     ret = svq3_get_ue_golomb(gb);
yading@10: 
yading@10:     if (ret) {
yading@10:         OPEN_READER(re, gb);
yading@10:         UPDATE_CACHE(re, gb);
yading@10:         buf = SHOW_SBITS(re, gb, 1);
yading@10:         LAST_SKIP_BITS(re, gb, 1);
yading@10:         ret = (ret ^ buf) - buf;
yading@10:         CLOSE_READER(re, gb);
yading@10:     }
yading@10: 
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read unsigned golomb rice code (ffv1).
yading@10:  */
yading@10: static inline int get_ur_golomb(GetBitContext *gb, int k, int limit, int esc_len){
yading@10:     unsigned int buf;
yading@10:     int log;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     log= av_log2(buf);
yading@10: 
yading@10:     if(log > 31-limit){
yading@10:         buf >>= log - k;
yading@10:         buf += (30-log)<<k;
yading@10:         LAST_SKIP_BITS(re, gb, 32 + k - log);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return buf;
yading@10:     }else{
yading@10:         LAST_SKIP_BITS(re, gb, limit);
yading@10:         UPDATE_CACHE(re, gb);
yading@10: 
yading@10:         buf = SHOW_UBITS(re, gb, esc_len);
yading@10: 
yading@10:         LAST_SKIP_BITS(re, gb, esc_len);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return buf + limit - 1;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read unsigned golomb rice code (jpegls).
yading@10:  */
yading@10: static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len){
yading@10:     unsigned int buf;
yading@10:     int log;
yading@10: 
yading@10:     OPEN_READER(re, gb);
yading@10:     UPDATE_CACHE(re, gb);
yading@10:     buf=GET_CACHE(re, gb);
yading@10: 
yading@10:     log= av_log2(buf);
yading@10: 
yading@10:     if(log - k >= 32-MIN_CACHE_BITS+(MIN_CACHE_BITS==32) && 32-log < limit){
yading@10:         buf >>= log - k;
yading@10:         buf += (30-log)<<k;
yading@10:         LAST_SKIP_BITS(re, gb, 32 + k - log);
yading@10:         CLOSE_READER(re, gb);
yading@10: 
yading@10:         return buf;
yading@10:     }else{
yading@10:         int i;
yading@10:         for (i = 0; i < limit && SHOW_UBITS(re, gb, 1) == 0; i++) {
yading@10:             if (gb->size_in_bits <= re_index)
yading@10:                 return -1;
yading@10:             LAST_SKIP_BITS(re, gb, 1);
yading@10:             UPDATE_CACHE(re, gb);
yading@10:         }
yading@10:         SKIP_BITS(re, gb, 1);
yading@10: 
yading@10:         if(i < limit - 1){
yading@10:             if(k){
yading@10:                 buf = SHOW_UBITS(re, gb, k);
yading@10:                 LAST_SKIP_BITS(re, gb, k);
yading@10:             }else{
yading@10:                 buf=0;
yading@10:             }
yading@10: 
yading@10:             CLOSE_READER(re, gb);
yading@10:             return buf + (i<<k);
yading@10:         }else if(i == limit - 1){
yading@10:             buf = SHOW_UBITS(re, gb, esc_len);
yading@10:             LAST_SKIP_BITS(re, gb, esc_len);
yading@10:             CLOSE_READER(re, gb);
yading@10: 
yading@10:             return buf + 1;
yading@10:         }else
yading@10:             return -1;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read signed golomb rice code (ffv1).
yading@10:  */
yading@10: static inline int get_sr_golomb(GetBitContext *gb, int k, int limit, int esc_len){
yading@10:     int v= get_ur_golomb(gb, k, limit, esc_len);
yading@10: 
yading@10:     v++;
yading@10:     if (v&1) return v>>1;
yading@10:     else return -(v>>1);
yading@10: 
yading@10: //    return (v>>1) ^ -(v&1);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read signed golomb rice code (flac).
yading@10:  */
yading@10: static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit, int esc_len){
yading@10:     int v= get_ur_golomb_jpegls(gb, k, limit, esc_len);
yading@10:     return (v>>1) ^ -(v&1);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read unsigned golomb rice code (shorten).
yading@10:  */
yading@10: static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k){
yading@10:         return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * read signed golomb rice code (shorten).
yading@10:  */
yading@10: static inline int get_sr_golomb_shorten(GetBitContext* gb, int k)
yading@10: {
yading@10:     int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
yading@10:     if (uvar & 1)
yading@10:         return ~(uvar >> 1);
yading@10:     else
yading@10:         return uvar >> 1;
yading@10: }
yading@10: 
yading@10: 
yading@10: 
yading@10: #ifdef TRACE
yading@10: 
yading@10: static inline int get_ue(GetBitContext *s, const char *file, const char *func,
yading@10:                          int line)
yading@10: {
yading@10:     int show= show_bits(s, 24);
yading@10:     int pos= get_bits_count(s);
yading@10:     int i= get_ue_golomb(s);
yading@10:     int len= get_bits_count(s) - pos;
yading@10:     int bits= show>>(24-len);
yading@10: 
yading@10:     print_bin(bits, len);
yading@10: 
yading@10:     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
yading@10: 
yading@10:     return i;
yading@10: }
yading@10: 
yading@10: static inline int get_se(GetBitContext *s, const char *file, const char *func,
yading@10:                          int line)
yading@10: {
yading@10:     int show= show_bits(s, 24);
yading@10:     int pos= get_bits_count(s);
yading@10:     int i= get_se_golomb(s);
yading@10:     int len= get_bits_count(s) - pos;
yading@10:     int bits= show>>(24-len);
yading@10: 
yading@10:     print_bin(bits, len);
yading@10: 
yading@10:     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
yading@10: 
yading@10:     return i;
yading@10: }
yading@10: 
yading@10: static inline int get_te(GetBitContext *s, int r, char *file, const char *func, int line){
yading@10:     int show= show_bits(s, 24);
yading@10:     int pos= get_bits_count(s);
yading@10:     int i= get_te0_golomb(s, r);
yading@10:     int len= get_bits_count(s) - pos;
yading@10:     int bits= show>>(24-len);
yading@10: 
yading@10:     print_bin(bits, len);
yading@10: 
yading@10:     av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te  @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
yading@10: 
yading@10:     return i;
yading@10: }
yading@10: 
yading@10: #define get_ue_golomb(a) get_ue(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@10: #define get_se_golomb(a) get_se(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@10: #define get_te_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@10: #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@10: 
yading@10: #endif
yading@10: 
yading@10: /**
yading@10:  * write unsigned exp golomb code.
yading@10:  */
yading@10: static inline void set_ue_golomb(PutBitContext *pb, int i){
yading@10:     int e;
yading@10: 
yading@10:     av_assert2(i>=0);
yading@10: 
yading@10: #if 0
yading@10:     if(i=0){
yading@10:         put_bits(pb, 1, 1);
yading@10:         return;
yading@10:     }
yading@10: #endif
yading@10:     if(i<256)
yading@10:         put_bits(pb, ff_ue_golomb_len[i], i+1);
yading@10:     else{
yading@10:         e= av_log2(i+1);
yading@10: 
yading@10:         put_bits(pb, 2*e+1, i+1);
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * write truncated unsigned exp golomb code.
yading@10:  */
yading@10: static inline void set_te_golomb(PutBitContext *pb, int i, int range){
yading@10:     av_assert2(range >= 1);
yading@10:     av_assert2(i<=range);
yading@10: 
yading@10:     if(range==2) put_bits(pb, 1, i^1);
yading@10:     else         set_ue_golomb(pb, i);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * write signed exp golomb code. 16 bits at most.
yading@10:  */
yading@10: static inline void set_se_golomb(PutBitContext *pb, int i){
yading@10: #if 0
yading@10:     if(i<=0) i= -2*i;
yading@10:     else     i=  2*i-1;
yading@10: #elif 1
yading@10:     i= 2*i-1;
yading@10:     if(i<0) i^= -1; //FIXME check if gcc does the right thing
yading@10: #else
yading@10:     i= 2*i-1;
yading@10:     i^= (i>>31);
yading@10: #endif
yading@10:     set_ue_golomb(pb, i);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * write unsigned golomb rice code (ffv1).
yading@10:  */
yading@10: static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
yading@10:     int e;
yading@10: 
yading@10:     av_assert2(i>=0);
yading@10: 
yading@10:     e= i>>k;
yading@10:     if(e<limit){
yading@10:         put_bits(pb, e + k + 1, (1<<k) + (i&((1<<k)-1)));
yading@10:     }else{
yading@10:         put_bits(pb, limit + esc_len, i - limit + 1);
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * write unsigned golomb rice code (jpegls).
yading@10:  */
yading@10: static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k, int limit, int esc_len){
yading@10:     int e;
yading@10: 
yading@10:     av_assert2(i>=0);
yading@10: 
yading@10:     e= (i>>k) + 1;
yading@10:     if(e<limit){
yading@10:         while(e > 31) {
yading@10:             put_bits(pb, 31, 0);
yading@10:             e -= 31;
yading@10:         }
yading@10:         put_bits(pb, e, 1);
yading@10:         if(k)
yading@10:             put_sbits(pb, k, i);
yading@10:     }else{
yading@10:         while(limit > 31) {
yading@10:             put_bits(pb, 31, 0);
yading@10:             limit -= 31;
yading@10:         }
yading@10:         put_bits(pb, limit  , 1);
yading@10:         put_bits(pb, esc_len, i - 1);
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * write signed golomb rice code (ffv1).
yading@10:  */
yading@10: static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
yading@10:     int v;
yading@10: 
yading@10:     v = -2*i-1;
yading@10:     v ^= (v>>31);
yading@10: 
yading@10:     set_ur_golomb(pb, v, k, limit, esc_len);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * write signed golomb rice code (flac).
yading@10:  */
yading@10: static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k, int limit, int esc_len){
yading@10:     int v;
yading@10: 
yading@10:     v = -2*i-1;
yading@10:     v ^= (v>>31);
yading@10: 
yading@10:     set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
yading@10: }
yading@10: 
yading@10: #endif /* AVCODEC_GOLOMB_H */