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00026 #ifndef AVCODEC_PUT_BITS_H
00027 #define AVCODEC_PUT_BITS_H
00028
00029 #include <stdint.h>
00030 #include <stdlib.h>
00031 #include <assert.h>
00032 #include "libavutil/bswap.h"
00033 #include "libavutil/common.h"
00034 #include "libavutil/intreadwrite.h"
00035 #include "libavutil/log.h"
00036 #include "mathops.h"
00037 #include "config.h"
00038
00039 typedef struct PutBitContext {
00040 uint32_t bit_buf;
00041 int bit_left;
00042 uint8_t *buf, *buf_ptr, *buf_end;
00043 int size_in_bits;
00044 } PutBitContext;
00045
00052 static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
00053 {
00054 if(buffer_size < 0) {
00055 buffer_size = 0;
00056 buffer = NULL;
00057 }
00058
00059 s->size_in_bits= 8*buffer_size;
00060 s->buf = buffer;
00061 s->buf_end = s->buf + buffer_size;
00062 s->buf_ptr = s->buf;
00063 s->bit_left=32;
00064 s->bit_buf=0;
00065 }
00066
00070 static inline int put_bits_count(PutBitContext *s)
00071 {
00072 return (s->buf_ptr - s->buf) * 8 + 32 - s->bit_left;
00073 }
00074
00078 static inline int put_bits_left(PutBitContext* s)
00079 {
00080 return (s->buf_end - s->buf_ptr) * 8 - 32 + s->bit_left;
00081 }
00082
00086 static inline void flush_put_bits(PutBitContext *s)
00087 {
00088 #ifndef BITSTREAM_WRITER_LE
00089 if (s->bit_left < 32)
00090 s->bit_buf<<= s->bit_left;
00091 #endif
00092 while (s->bit_left < 32) {
00093
00094 #ifdef BITSTREAM_WRITER_LE
00095 *s->buf_ptr++=s->bit_buf;
00096 s->bit_buf>>=8;
00097 #else
00098 *s->buf_ptr++=s->bit_buf >> 24;
00099 s->bit_buf<<=8;
00100 #endif
00101 s->bit_left+=8;
00102 }
00103 s->bit_left=32;
00104 s->bit_buf=0;
00105 }
00106
00107 #ifdef BITSTREAM_WRITER_LE
00108 #define avpriv_align_put_bits align_put_bits_unsupported_here
00109 #define ff_put_string ff_put_string_unsupported_here
00110 #define avpriv_copy_bits avpriv_copy_bits_unsupported_here
00111 #else
00112
00115 void avpriv_align_put_bits(PutBitContext *s);
00116
00122 void ff_put_string(PutBitContext *pb, const char *string, int terminate_string);
00123
00129 void avpriv_copy_bits(PutBitContext *pb, const uint8_t *src, int length);
00130 #endif
00131
00136 static inline void put_bits(PutBitContext *s, int n, unsigned int value)
00137 {
00138 unsigned int bit_buf;
00139 int bit_left;
00140
00141
00142 assert(n <= 31 && value < (1U << n));
00143
00144 bit_buf = s->bit_buf;
00145 bit_left = s->bit_left;
00146
00147
00148
00149 #ifdef BITSTREAM_WRITER_LE
00150 bit_buf |= value << (32 - bit_left);
00151 if (n >= bit_left) {
00152 AV_WL32(s->buf_ptr, bit_buf);
00153 s->buf_ptr+=4;
00154 bit_buf = (bit_left==32)?0:value >> bit_left;
00155 bit_left+=32;
00156 }
00157 bit_left-=n;
00158 #else
00159 if (n < bit_left) {
00160 bit_buf = (bit_buf<<n) | value;
00161 bit_left-=n;
00162 } else {
00163 bit_buf<<=bit_left;
00164 bit_buf |= value >> (n - bit_left);
00165 AV_WB32(s->buf_ptr, bit_buf);
00166
00167 s->buf_ptr+=4;
00168 bit_left+=32 - n;
00169 bit_buf = value;
00170 }
00171 #endif
00172
00173 s->bit_buf = bit_buf;
00174 s->bit_left = bit_left;
00175 }
00176
00177 static inline void put_sbits(PutBitContext *pb, int n, int32_t value)
00178 {
00179 assert(n >= 0 && n <= 31);
00180
00181 put_bits(pb, n, value & ((1<<n)-1));
00182 }
00183
00187 static void av_unused put_bits32(PutBitContext *s, uint32_t value)
00188 {
00189 int lo = value & 0xffff;
00190 int hi = value >> 16;
00191 #ifdef BITSTREAM_WRITER_LE
00192 put_bits(s, 16, lo);
00193 put_bits(s, 16, hi);
00194 #else
00195 put_bits(s, 16, hi);
00196 put_bits(s, 16, lo);
00197 #endif
00198 }
00199
00204 static inline uint8_t* put_bits_ptr(PutBitContext *s)
00205 {
00206 return s->buf_ptr;
00207 }
00208
00213 static inline void skip_put_bytes(PutBitContext *s, int n)
00214 {
00215 assert((put_bits_count(s)&7)==0);
00216 assert(s->bit_left==32);
00217 s->buf_ptr += n;
00218 }
00219
00225 static inline void skip_put_bits(PutBitContext *s, int n)
00226 {
00227 s->bit_left -= n;
00228 s->buf_ptr-= 4*(s->bit_left>>5);
00229 s->bit_left &= 31;
00230 }
00231
00237 static inline void set_put_bits_buffer_size(PutBitContext *s, int size)
00238 {
00239 s->buf_end= s->buf + size;
00240 }
00241
00242 #endif