mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-26 17:32:06 +00:00
851 lines
22 KiB
C
851 lines
22 KiB
C
/**
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* @file bitstream.h
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* bitstream api header.
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*/
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#ifndef BITSTREAM_H
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#define BITSTREAM_H
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//#define ALT_BITSTREAM_WRITER
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//#define ALIGNED_BITSTREAM_WRITER
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#define ALT_BITSTREAM_READER
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//#define LIBMPEG2_BITSTREAM_READER
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//#define A32_BITSTREAM_READER
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#define LIBMPEG2_BITSTREAM_READER_HACK //add BERO
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#if defined(ARCH_X86) || defined(ARCH_X86_64)
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// avoid +32 for shift optimization (gcc should do that ...)
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static inline int32_t NEG_SSR32( int32_t a, int8_t s){
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asm ("sarl %1, %0\n\t"
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: "+r" (a)
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: "ic" ((uint8_t)(-s))
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);
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return a;
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}
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static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
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asm ("shrl %1, %0\n\t"
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: "+r" (a)
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: "ic" ((uint8_t)(-s))
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);
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return a;
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}
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#else
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# define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
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# define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
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#endif
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/* bit output */
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/* buf and buf_end must be present and used by every alternative writer. */
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typedef struct PutBitContext {
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#ifdef ALT_BITSTREAM_WRITER
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uint8_t *buf, *buf_end;
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int index;
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#else
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uint32_t bit_buf;
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int bit_left;
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uint8_t *buf, *buf_ptr, *buf_end;
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#endif
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} PutBitContext;
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static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
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{
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s->buf = buffer;
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s->buf_end = s->buf + buffer_size;
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#ifdef ALT_BITSTREAM_WRITER
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s->index=0;
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((uint32_t*)(s->buf))[0]=0;
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// memset(buffer, 0, buffer_size);
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#else
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s->buf_ptr = s->buf;
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s->bit_left=32;
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s->bit_buf=0;
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#endif
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}
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/* return the number of bits output */
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static inline int put_bits_count(PutBitContext *s)
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{
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#ifdef ALT_BITSTREAM_WRITER
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return s->index;
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#else
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return (s->buf_ptr - s->buf) * 8 + 32 - s->bit_left;
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#endif
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}
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/* pad the end of the output stream with zeros */
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static inline void flush_put_bits(PutBitContext *s)
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{
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#ifdef ALT_BITSTREAM_WRITER
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align_put_bits(s);
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#else
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s->bit_buf<<= s->bit_left;
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while (s->bit_left < 32) {
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/* XXX: should test end of buffer */
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*s->buf_ptr++=s->bit_buf >> 24;
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s->bit_buf<<=8;
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s->bit_left+=8;
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}
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s->bit_left=32;
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s->bit_buf=0;
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#endif
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}
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void align_put_bits(PutBitContext *s);
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void put_string(PutBitContext * pbc, char *s, int put_zero);
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/* bit input */
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/* buffer, buffer_end and size_in_bits must be present and used by every reader */
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typedef struct GetBitContext {
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const uint8_t *buffer, *buffer_end;
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#ifdef ALT_BITSTREAM_READER
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int index;
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#elif defined LIBMPEG2_BITSTREAM_READER
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uint8_t *buffer_ptr;
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uint32_t cache;
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int bit_count;
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#elif defined A32_BITSTREAM_READER
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uint32_t *buffer_ptr;
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uint32_t cache0;
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uint32_t cache1;
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int bit_count;
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#endif
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int size_in_bits;
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} GetBitContext;
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#define VLC_TYPE int16_t
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typedef struct VLC {
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int bits;
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VLC_TYPE (*table)[2]; ///< code, bits
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int table_size, table_allocated;
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} VLC;
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typedef struct RL_VLC_ELEM {
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int16_t level;
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int8_t len;
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uint8_t run;
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} RL_VLC_ELEM;
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#ifdef ARCH_SPARC
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#define UNALIGNED_STORES_ARE_BAD
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#endif
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/* used to avoid missaligned exceptions on some archs (alpha, ...) */
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#if defined(ARCH_X86) || defined(ARCH_X86_64)
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# define unaligned32(a) (*(const uint32_t*)(a))
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#else
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# ifdef __GNUC__
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static inline uint32_t unaligned32(const void *v) {
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struct Unaligned {
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uint32_t i;
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} __attribute__((packed));
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return ((const struct Unaligned *) v)->i;
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}
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# elif defined(__DECC)
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static inline uint32_t unaligned32(const void *v) {
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return *(const __unaligned uint32_t *) v;
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}
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# else
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static inline uint32_t unaligned32(const void *v) {
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return *(const uint32_t *) v;
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}
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# endif
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#endif //!ARCH_X86
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#ifndef ALT_BITSTREAM_WRITER
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static inline void put_bits(PutBitContext *s, int n, unsigned int value)
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{
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unsigned int bit_buf;
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int bit_left;
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#ifdef STATS
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st_out_bit_counts[st_current_index] += n;
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#endif
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// printf("put_bits=%d %x\n", n, value);
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assert(n == 32 || value < (1U << n));
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bit_buf = s->bit_buf;
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bit_left = s->bit_left;
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// printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
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/* XXX: optimize */
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if (n < bit_left) {
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bit_buf = (bit_buf<<n) | value;
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bit_left-=n;
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} else {
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bit_buf<<=bit_left;
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bit_buf |= value >> (n - bit_left);
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#ifdef UNALIGNED_STORES_ARE_BAD
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if (3 & (intptr_t) s->buf_ptr) {
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s->buf_ptr[0] = bit_buf >> 24;
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s->buf_ptr[1] = bit_buf >> 16;
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s->buf_ptr[2] = bit_buf >> 8;
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s->buf_ptr[3] = bit_buf ;
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} else
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#endif
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*(uint32_t *)s->buf_ptr = be2me_32(bit_buf);
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//printf("bitbuf = %08x\n", bit_buf);
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s->buf_ptr+=4;
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bit_left+=32 - n;
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bit_buf = value;
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}
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s->bit_buf = bit_buf;
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s->bit_left = bit_left;
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}
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#endif
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#ifdef ALT_BITSTREAM_WRITER
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static inline void put_bits(PutBitContext *s, int n, unsigned int value)
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{
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# ifdef ALIGNED_BITSTREAM_WRITER
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# if defined(ARCH_X86) || defined(ARCH_X86_64)
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asm volatile(
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"movl %0, %%ecx \n\t"
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"xorl %%eax, %%eax \n\t"
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"shrdl %%cl, %1, %%eax \n\t"
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"shrl %%cl, %1 \n\t"
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"movl %0, %%ecx \n\t"
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"shrl $3, %%ecx \n\t"
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"andl $0xFFFFFFFC, %%ecx \n\t"
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"bswapl %1 \n\t"
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"orl %1, (%2, %%ecx) \n\t"
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"bswapl %%eax \n\t"
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"addl %3, %0 \n\t"
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"movl %%eax, 4(%2, %%ecx) \n\t"
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: "=&r" (s->index), "=&r" (value)
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: "r" (s->buf), "r" (n), "0" (s->index), "1" (value<<(-n))
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: "%eax", "%ecx"
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);
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# else
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int index= s->index;
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uint32_t *ptr= ((uint32_t *)s->buf)+(index>>5);
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value<<= 32-n;
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ptr[0] |= be2me_32(value>>(index&31));
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ptr[1] = be2me_32(value<<(32-(index&31)));
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//if(n>24) printf("%d %d\n", n, value);
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index+= n;
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s->index= index;
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# endif
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# else //ALIGNED_BITSTREAM_WRITER
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# if defined(ARCH_X86) || defined(ARCH_X86_64)
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asm volatile(
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"movl $7, %%ecx \n\t"
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"andl %0, %%ecx \n\t"
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"addl %3, %%ecx \n\t"
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"negl %%ecx \n\t"
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"shll %%cl, %1 \n\t"
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"bswapl %1 \n\t"
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"movl %0, %%ecx \n\t"
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"shrl $3, %%ecx \n\t"
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"orl %1, (%%ecx, %2) \n\t"
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"addl %3, %0 \n\t"
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"movl $0, 4(%%ecx, %2) \n\t"
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: "=&r" (s->index), "=&r" (value)
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: "r" (s->buf), "r" (n), "0" (s->index), "1" (value)
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: "%ecx"
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);
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# else
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int index= s->index;
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uint32_t *ptr= (uint32_t*)(((uint8_t *)s->buf)+(index>>3));
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ptr[0] |= be2me_32(value<<(32-n-(index&7) ));
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ptr[1] = 0;
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//if(n>24) printf("%d %d\n", n, value);
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index+= n;
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s->index= index;
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# endif
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# endif //!ALIGNED_BITSTREAM_WRITER
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}
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#endif
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static inline uint8_t* pbBufPtr(PutBitContext *s)
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{
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#ifdef ALT_BITSTREAM_WRITER
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return s->buf + (s->index>>3);
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#else
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return s->buf_ptr;
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#endif
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}
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/**
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*
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* PutBitContext must be flushed & aligned to a byte boundary before calling this.
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*/
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static inline void skip_put_bytes(PutBitContext *s, int n){
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assert((put_bits_count(s)&7)==0);
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#ifdef ALT_BITSTREAM_WRITER
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FIXME may need some cleaning of the buffer
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s->index += n<<3;
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#else
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assert(s->bit_left==32);
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s->buf_ptr += n;
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#endif
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}
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/**
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* skips the given number of bits.
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* must only be used if the actual values in the bitstream dont matter
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*/
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static inline void skip_put_bits(PutBitContext *s, int n){
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#ifdef ALT_BITSTREAM_WRITER
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s->index += n;
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#else
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s->bit_left -= n;
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s->buf_ptr-= s->bit_left>>5;
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s->bit_left &= 31;
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#endif
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}
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/**
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* Changes the end of the buffer.
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*/
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static inline void set_put_bits_buffer_size(PutBitContext *s, int size){
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s->buf_end= s->buf + size;
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}
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/* Bitstream reader API docs:
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name
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abritary name which is used as prefix for the internal variables
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gb
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getbitcontext
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OPEN_READER(name, gb)
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loads gb into local variables
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CLOSE_READER(name, gb)
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stores local vars in gb
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UPDATE_CACHE(name, gb)
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refills the internal cache from the bitstream
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after this call at least MIN_CACHE_BITS will be available,
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GET_CACHE(name, gb)
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will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit)
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SHOW_UBITS(name, gb, num)
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will return the nest num bits
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SHOW_SBITS(name, gb, num)
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will return the nest num bits and do sign extension
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SKIP_BITS(name, gb, num)
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will skip over the next num bits
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note, this is equinvalent to SKIP_CACHE; SKIP_COUNTER
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SKIP_CACHE(name, gb, num)
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will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER)
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SKIP_COUNTER(name, gb, num)
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will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS)
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LAST_SKIP_CACHE(name, gb, num)
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will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing
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LAST_SKIP_BITS(name, gb, num)
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is equinvalent to SKIP_LAST_CACHE; SKIP_COUNTER
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for examples see get_bits, show_bits, skip_bits, get_vlc
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*/
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static inline int unaligned32_be(const void *v)
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{
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#ifdef CONFIG_ALIGN
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const uint8_t *p=v;
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return (((p[0]<<8) | p[1])<<16) | (p[2]<<8) | (p[3]);
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#else
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return be2me_32( unaligned32(v)); //original
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#endif
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}
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#ifdef ALT_BITSTREAM_READER
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# define MIN_CACHE_BITS 25
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# define OPEN_READER(name, gb)\
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int name##_index= (gb)->index;\
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int name##_cache= 0;\
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# define CLOSE_READER(name, gb)\
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(gb)->index= name##_index;\
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# define UPDATE_CACHE(name, gb)\
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name##_cache= unaligned32_be( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07);\
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# define SKIP_CACHE(name, gb, num)\
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name##_cache <<= (num);\
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// FIXME name?
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# define SKIP_COUNTER(name, gb, num)\
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name##_index += (num);\
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# define SKIP_BITS(name, gb, num)\
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{\
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SKIP_CACHE(name, gb, num)\
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SKIP_COUNTER(name, gb, num)\
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}\
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# define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
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# define LAST_SKIP_CACHE(name, gb, num) ;
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# define SHOW_UBITS(name, gb, num)\
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NEG_USR32(name##_cache, num)
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# define SHOW_SBITS(name, gb, num)\
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NEG_SSR32(name##_cache, num)
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# define GET_CACHE(name, gb)\
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((uint32_t)name##_cache)
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static inline int get_bits_count(GetBitContext *s){
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return s->index;
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}
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#elif defined LIBMPEG2_BITSTREAM_READER
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//libmpeg2 like reader
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# define MIN_CACHE_BITS 17
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# define OPEN_READER(name, gb)\
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int name##_bit_count=(gb)->bit_count;\
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int name##_cache= (gb)->cache;\
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uint8_t * name##_buffer_ptr=(gb)->buffer_ptr;\
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# define CLOSE_READER(name, gb)\
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(gb)->bit_count= name##_bit_count;\
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(gb)->cache= name##_cache;\
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(gb)->buffer_ptr= name##_buffer_ptr;\
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#ifdef LIBMPEG2_BITSTREAM_READER_HACK
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# define UPDATE_CACHE(name, gb)\
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if(name##_bit_count >= 0){\
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name##_cache+= (int)be2me_16(*(uint16_t*)name##_buffer_ptr) << name##_bit_count;\
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((uint16_t*)name##_buffer_ptr)++;\
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name##_bit_count-= 16;\
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}\
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#else
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# define UPDATE_CACHE(name, gb)\
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if(name##_bit_count >= 0){\
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name##_cache+= ((name##_buffer_ptr[0]<<8) + name##_buffer_ptr[1]) << name##_bit_count;\
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name##_buffer_ptr+=2;\
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name##_bit_count-= 16;\
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}\
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#endif
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# define SKIP_CACHE(name, gb, num)\
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name##_cache <<= (num);\
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# define SKIP_COUNTER(name, gb, num)\
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name##_bit_count += (num);\
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# define SKIP_BITS(name, gb, num)\
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{\
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SKIP_CACHE(name, gb, num)\
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SKIP_COUNTER(name, gb, num)\
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}\
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# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
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# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
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# define SHOW_UBITS(name, gb, num)\
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NEG_USR32(name##_cache, num)
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# define SHOW_SBITS(name, gb, num)\
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NEG_SSR32(name##_cache, num)
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# define GET_CACHE(name, gb)\
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((uint32_t)name##_cache)
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static inline int get_bits_count(GetBitContext *s){
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return (s->buffer_ptr - s->buffer)*8 - 16 + s->bit_count;
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}
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#elif defined A32_BITSTREAM_READER
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# define MIN_CACHE_BITS 32
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# define OPEN_READER(name, gb)\
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int name##_bit_count=(gb)->bit_count;\
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uint32_t name##_cache0= (gb)->cache0;\
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uint32_t name##_cache1= (gb)->cache1;\
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uint32_t * name##_buffer_ptr=(gb)->buffer_ptr;\
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# define CLOSE_READER(name, gb)\
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(gb)->bit_count= name##_bit_count;\
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(gb)->cache0= name##_cache0;\
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(gb)->cache1= name##_cache1;\
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(gb)->buffer_ptr= name##_buffer_ptr;\
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# define UPDATE_CACHE(name, gb)\
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if(name##_bit_count > 0){\
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const uint32_t next= be2me_32( *name##_buffer_ptr );\
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name##_cache0 |= NEG_USR32(next,name##_bit_count);\
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name##_cache1 |= next<<name##_bit_count;\
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name##_buffer_ptr++;\
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name##_bit_count-= 32;\
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}\
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#if defined(ARCH_X86) || defined(ARCH_X86_64)
|
|
# define SKIP_CACHE(name, gb, num)\
|
|
asm(\
|
|
"shldl %2, %1, %0 \n\t"\
|
|
"shll %2, %1 \n\t"\
|
|
: "+r" (name##_cache0), "+r" (name##_cache1)\
|
|
: "Ic" ((uint8_t)num)\
|
|
);
|
|
#else
|
|
# define SKIP_CACHE(name, gb, num)\
|
|
name##_cache0 <<= (num);\
|
|
name##_cache0 |= NEG_USR32(name##_cache1,num);\
|
|
name##_cache1 <<= (num);
|
|
#endif
|
|
|
|
# define SKIP_COUNTER(name, gb, num)\
|
|
name##_bit_count += (num);\
|
|
|
|
# define SKIP_BITS(name, gb, num)\
|
|
{\
|
|
SKIP_CACHE(name, gb, num)\
|
|
SKIP_COUNTER(name, gb, num)\
|
|
}\
|
|
|
|
# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
|
|
# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
|
|
|
|
# define SHOW_UBITS(name, gb, num)\
|
|
NEG_USR32(name##_cache0, num)
|
|
|
|
# define SHOW_SBITS(name, gb, num)\
|
|
NEG_SSR32(name##_cache0, num)
|
|
|
|
# define GET_CACHE(name, gb)\
|
|
(name##_cache0)
|
|
|
|
static inline int get_bits_count(GetBitContext *s){
|
|
return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count;
|
|
}
|
|
|
|
#endif
|
|
|
|
/**
|
|
* read mpeg1 dc style vlc (sign bit + mantisse with no MSB).
|
|
* if MSB not set it is negative
|
|
* @param n length in bits
|
|
* @author BERO
|
|
*/
|
|
static inline int get_xbits(GetBitContext *s, int n){
|
|
register int tmp;
|
|
register int32_t cache;
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
cache = GET_CACHE(re,s);
|
|
if ((int32_t)cache<0) { //MSB=1
|
|
tmp = NEG_USR32(cache,n);
|
|
} else {
|
|
// tmp = (-1<<n) | NEG_USR32(cache,n) + 1; mpeg12.c algo
|
|
// tmp = - (NEG_USR32(cache,n) ^ ((1 << n) - 1)); h263.c algo
|
|
tmp = - NEG_USR32(~cache,n);
|
|
}
|
|
LAST_SKIP_BITS(re, s, n)
|
|
CLOSE_READER(re, s)
|
|
return tmp;
|
|
}
|
|
|
|
static inline int get_sbits(GetBitContext *s, int n){
|
|
register int tmp;
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
tmp= SHOW_SBITS(re, s, n);
|
|
LAST_SKIP_BITS(re, s, n)
|
|
CLOSE_READER(re, s)
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* reads 0-17 bits.
|
|
* Note, the alt bitstream reader can read upto 25 bits, but the libmpeg2 reader cant
|
|
*/
|
|
static inline unsigned int get_bits(GetBitContext *s, int n){
|
|
register int tmp;
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
tmp= SHOW_UBITS(re, s, n);
|
|
LAST_SKIP_BITS(re, s, n)
|
|
CLOSE_READER(re, s)
|
|
return tmp;
|
|
}
|
|
|
|
unsigned int get_bits_long(GetBitContext *s, int n);
|
|
|
|
/**
|
|
* shows 0-17 bits.
|
|
* Note, the alt bitstream reader can read upto 25 bits, but the libmpeg2 reader cant
|
|
*/
|
|
static inline unsigned int show_bits(GetBitContext *s, int n){
|
|
register int tmp;
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
tmp= SHOW_UBITS(re, s, n);
|
|
// CLOSE_READER(re, s)
|
|
return tmp;
|
|
}
|
|
|
|
unsigned int show_bits_long(GetBitContext *s, int n);
|
|
|
|
static inline void skip_bits(GetBitContext *s, int n){
|
|
//Note gcc seems to optimize this to s->index+=n for the ALT_READER :))
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
LAST_SKIP_BITS(re, s, n)
|
|
CLOSE_READER(re, s)
|
|
}
|
|
|
|
static inline unsigned int get_bits1(GetBitContext *s){
|
|
#ifdef ALT_BITSTREAM_READER
|
|
int index= s->index;
|
|
uint8_t result= s->buffer[ index>>3 ];
|
|
result<<= (index&0x07);
|
|
result>>= 8 - 1;
|
|
index++;
|
|
s->index= index;
|
|
|
|
return result;
|
|
#else
|
|
return get_bits(s, 1);
|
|
#endif
|
|
}
|
|
|
|
static inline unsigned int show_bits1(GetBitContext *s){
|
|
return show_bits(s, 1);
|
|
}
|
|
|
|
static inline void skip_bits1(GetBitContext *s){
|
|
skip_bits(s, 1);
|
|
}
|
|
|
|
/**
|
|
* init GetBitContext.
|
|
* @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger then the actual read bits
|
|
* because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
|
|
* @param bit_size the size of the buffer in bits
|
|
*/
|
|
static inline void init_get_bits(GetBitContext *s,
|
|
const uint8_t *buffer, int bit_size)
|
|
{
|
|
const int buffer_size= (bit_size+7)>>3;
|
|
|
|
s->buffer= buffer;
|
|
s->size_in_bits= bit_size;
|
|
s->buffer_end= buffer + buffer_size;
|
|
#ifdef ALT_BITSTREAM_READER
|
|
s->index=0;
|
|
#elif defined LIBMPEG2_BITSTREAM_READER
|
|
#ifdef LIBMPEG2_BITSTREAM_READER_HACK
|
|
if ((int)buffer&1) {
|
|
/* word alignment */
|
|
s->cache = (*buffer++)<<24;
|
|
s->buffer_ptr = buffer;
|
|
s->bit_count = 16-8;
|
|
} else
|
|
#endif
|
|
{
|
|
s->buffer_ptr = buffer;
|
|
s->bit_count = 16;
|
|
s->cache = 0;
|
|
}
|
|
#elif defined A32_BITSTREAM_READER
|
|
s->buffer_ptr = (uint32_t*)buffer;
|
|
s->bit_count = 32;
|
|
s->cache0 = 0;
|
|
s->cache1 = 0;
|
|
#endif
|
|
{
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
CLOSE_READER(re, s)
|
|
}
|
|
#ifdef A32_BITSTREAM_READER
|
|
s->cache1 = 0;
|
|
#endif
|
|
}
|
|
|
|
int check_marker(GetBitContext *s, const char *msg);
|
|
void align_get_bits(GetBitContext *s);
|
|
int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
|
|
const void *bits, int bits_wrap, int bits_size,
|
|
const void *codes, int codes_wrap, int codes_size,
|
|
int use_static);
|
|
void free_vlc(VLC *vlc);
|
|
|
|
/**
|
|
*
|
|
* if the vlc code is invalid and max_depth=1 than no bits will be removed
|
|
* if the vlc code is invalid and max_depth>1 than the number of bits removed
|
|
* is undefined
|
|
*/
|
|
#define GET_VLC(code, name, gb, table, bits, max_depth)\
|
|
{\
|
|
int n, index, nb_bits;\
|
|
\
|
|
index= SHOW_UBITS(name, gb, bits);\
|
|
code = table[index][0];\
|
|
n = table[index][1];\
|
|
\
|
|
if(max_depth > 1 && n < 0){\
|
|
LAST_SKIP_BITS(name, gb, bits)\
|
|
UPDATE_CACHE(name, gb)\
|
|
\
|
|
nb_bits = -n;\
|
|
\
|
|
index= SHOW_UBITS(name, gb, nb_bits) + code;\
|
|
code = table[index][0];\
|
|
n = table[index][1];\
|
|
if(max_depth > 2 && n < 0){\
|
|
LAST_SKIP_BITS(name, gb, nb_bits)\
|
|
UPDATE_CACHE(name, gb)\
|
|
\
|
|
nb_bits = -n;\
|
|
\
|
|
index= SHOW_UBITS(name, gb, nb_bits) + code;\
|
|
code = table[index][0];\
|
|
n = table[index][1];\
|
|
}\
|
|
}\
|
|
SKIP_BITS(name, gb, n)\
|
|
}
|
|
|
|
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth)\
|
|
{\
|
|
int n, index, nb_bits;\
|
|
\
|
|
index= SHOW_UBITS(name, gb, bits);\
|
|
level = table[index].level;\
|
|
n = table[index].len;\
|
|
\
|
|
if(max_depth > 1 && n < 0){\
|
|
LAST_SKIP_BITS(name, gb, bits)\
|
|
UPDATE_CACHE(name, gb)\
|
|
\
|
|
nb_bits = -n;\
|
|
\
|
|
index= SHOW_UBITS(name, gb, nb_bits) + level;\
|
|
level = table[index].level;\
|
|
n = table[index].len;\
|
|
}\
|
|
run= table[index].run;\
|
|
SKIP_BITS(name, gb, n)\
|
|
}
|
|
|
|
// deprecated, dont use get_vlc for new code, use get_vlc2 instead or use GET_VLC directly
|
|
static inline int get_vlc(GetBitContext *s, VLC *vlc)
|
|
{
|
|
int code;
|
|
VLC_TYPE (*table)[2]= vlc->table;
|
|
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
|
|
GET_VLC(code, re, s, table, vlc->bits, 3)
|
|
|
|
CLOSE_READER(re, s)
|
|
return code;
|
|
}
|
|
|
|
/**
|
|
* parses a vlc code, faster then get_vlc()
|
|
* @param bits is the number of bits which will be read at once, must be
|
|
* identical to nb_bits in init_vlc()
|
|
* @param max_depth is the number of times bits bits must be readed to completly
|
|
* read the longest vlc code
|
|
* = (max_vlc_length + bits - 1) / bits
|
|
*/
|
|
static always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
|
|
int bits, int max_depth)
|
|
{
|
|
int code;
|
|
|
|
OPEN_READER(re, s)
|
|
UPDATE_CACHE(re, s)
|
|
|
|
GET_VLC(code, re, s, table, bits, max_depth)
|
|
|
|
CLOSE_READER(re, s)
|
|
return code;
|
|
}
|
|
|
|
//#define TRACE
|
|
|
|
#ifdef TRACE
|
|
#include "avcodec.h"
|
|
static inline void print_bin(int bits, int n){
|
|
int i;
|
|
|
|
for(i=n-1; i>=0; i--){
|
|
av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1);
|
|
}
|
|
for(i=n; i<24; i++)
|
|
av_log(NULL, AV_LOG_DEBUG, " ");
|
|
}
|
|
|
|
static inline int get_bits_trace(GetBitContext *s, int n, char *file, const char *func, int line){
|
|
int r= get_bits(s, n);
|
|
|
|
print_bin(r, n);
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n", r, n, r, get_bits_count(s)-n, file, func, line);
|
|
return r;
|
|
}
|
|
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2], int bits, int max_depth, char *file, const char *func, int line){
|
|
int show= show_bits(s, 24);
|
|
int pos= get_bits_count(s);
|
|
int r= get_vlc2(s, table, bits, max_depth);
|
|
int len= get_bits_count(s) - pos;
|
|
int bits2= show>>(24-len);
|
|
|
|
print_bin(bits2, len);
|
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n", bits2, len, r, pos, file, func, line);
|
|
return r;
|
|
}
|
|
static inline int get_xbits_trace(GetBitContext *s, int n, char *file, const char *func, int line){
|
|
int show= show_bits(s, n);
|
|
int r= get_xbits(s, n);
|
|
|
|
print_bin(show, n);
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n", show, n, r, get_bits_count(s)-n, file, func, line);
|
|
return r;
|
|
}
|
|
|
|
#define get_bits(s, n) get_bits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
#define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
#define get_vlc(s, vlc) get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
#define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
|
|
#define tprintf(...) av_log(NULL, AV_LOG_DEBUG, __VA_ARGS__)
|
|
|
|
#else //TRACE
|
|
#define tprintf(...) {}
|
|
#endif
|
|
|
|
static inline int decode012(GetBitContext *gb){
|
|
int n;
|
|
n = get_bits1(gb);
|
|
if (n == 0)
|
|
return 0;
|
|
else
|
|
return get_bits1(gb) + 1;
|
|
}
|
|
|
|
#endif /* BITSTREAM_H */
|