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-rw-r--r--contrib/ffmpeg/libavcodec/bitstream.h956
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diff --git a/contrib/ffmpeg/libavcodec/bitstream.h b/contrib/ffmpeg/libavcodec/bitstream.h
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+++ b/contrib/ffmpeg/libavcodec/bitstream.h
@@ -0,0 +1,956 @@
+/*
+ * 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 bitstream.h
+ * bitstream api header.
+ */
+
+#ifndef BITSTREAM_H
+#define BITSTREAM_H
+
+#include "log.h"
+
+#if defined(ALT_BITSTREAM_READER_LE) && !defined(ALT_BITSTREAM_READER)
+#define ALT_BITSTREAM_READER
+#endif
+
+//#define ALT_BITSTREAM_WRITER
+//#define ALIGNED_BITSTREAM_WRITER
+#if !defined(LIBMPEG2_BITSTREAM_READER) && !defined(A32_BITSTREAM_READER) && !defined(ALT_BITSTREAM_READER)
+# ifdef ARCH_ARMV4L
+# define A32_BITSTREAM_READER
+# else
+#define ALT_BITSTREAM_READER
+//#define LIBMPEG2_BITSTREAM_READER
+//#define A32_BITSTREAM_READER
+# endif
+#endif
+#define LIBMPEG2_BITSTREAM_READER_HACK //add BERO
+
+extern const uint8_t ff_reverse[256];
+
+#if defined(ARCH_X86)
+// avoid +32 for shift optimization (gcc should do that ...)
+static inline int32_t NEG_SSR32( int32_t a, int8_t s){
+ asm ("sarl %1, %0\n\t"
+ : "+r" (a)
+ : "ic" ((uint8_t)(-s))
+ );
+ return a;
+}
+static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
+ asm ("shrl %1, %0\n\t"
+ : "+r" (a)
+ : "ic" ((uint8_t)(-s))
+ );
+ return a;
+}
+#else
+# define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
+# define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
+#endif
+
+/* bit output */
+
+/* buf and buf_end must be present and used by every alternative writer. */
+typedef struct PutBitContext {
+#ifdef ALT_BITSTREAM_WRITER
+ uint8_t *buf, *buf_end;
+ int index;
+#else
+ uint32_t bit_buf;
+ int bit_left;
+ uint8_t *buf, *buf_ptr, *buf_end;
+#endif
+} PutBitContext;
+
+static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
+{
+ if(buffer_size < 0) {
+ buffer_size = 0;
+ buffer = NULL;
+ }
+
+ s->buf = buffer;
+ s->buf_end = s->buf + buffer_size;
+#ifdef ALT_BITSTREAM_WRITER
+ s->index=0;
+ ((uint32_t*)(s->buf))[0]=0;
+// memset(buffer, 0, buffer_size);
+#else
+ s->buf_ptr = s->buf;
+ s->bit_left=32;
+ s->bit_buf=0;
+#endif
+}
+
+/* return the number of bits output */
+static inline int put_bits_count(PutBitContext *s)
+{
+#ifdef ALT_BITSTREAM_WRITER
+ return s->index;
+#else
+ return (s->buf_ptr - s->buf) * 8 + 32 - s->bit_left;
+#endif
+}
+
+/* pad the end of the output stream with zeros */
+static inline void flush_put_bits(PutBitContext *s)
+{
+#ifdef ALT_BITSTREAM_WRITER
+ align_put_bits(s);
+#else
+ s->bit_buf<<= s->bit_left;
+ while (s->bit_left < 32) {
+ /* XXX: should test end of buffer */
+ *s->buf_ptr++=s->bit_buf >> 24;
+ s->bit_buf<<=8;
+ s->bit_left+=8;
+ }
+ s->bit_left=32;
+ s->bit_buf=0;
+#endif
+}
+
+void align_put_bits(PutBitContext *s);
+void ff_put_string(PutBitContext * pbc, char *s, int put_zero);
+
+/* bit input */
+/* buffer, buffer_end and size_in_bits must be present and used by every reader */
+typedef struct GetBitContext {
+ const uint8_t *buffer, *buffer_end;
+#ifdef ALT_BITSTREAM_READER
+ int index;
+#elif defined LIBMPEG2_BITSTREAM_READER
+ uint8_t *buffer_ptr;
+ uint32_t cache;
+ int bit_count;
+#elif defined A32_BITSTREAM_READER
+ uint32_t *buffer_ptr;
+ uint32_t cache0;
+ uint32_t cache1;
+ int bit_count;
+#endif
+ int size_in_bits;
+} GetBitContext;
+
+#define VLC_TYPE int16_t
+
+typedef struct VLC {
+ int bits;
+ VLC_TYPE (*table)[2]; ///< code, bits
+ int table_size, table_allocated;
+} VLC;
+
+typedef struct RL_VLC_ELEM {
+ int16_t level;
+ int8_t len;
+ uint8_t run;
+} RL_VLC_ELEM;
+
+#if defined(ARCH_SPARC) || defined(ARCH_ARMV4L) || defined(ARCH_MIPS)
+#define UNALIGNED_STORES_ARE_BAD
+#endif
+
+/* used to avoid missaligned exceptions on some archs (alpha, ...) */
+#if defined(ARCH_X86)
+# define unaligned16(a) (*(const uint16_t*)(a))
+# define unaligned32(a) (*(const uint32_t*)(a))
+# define unaligned64(a) (*(const uint64_t*)(a))
+#else
+# ifdef __GNUC__
+# define unaligned(x) \
+static inline uint##x##_t unaligned##x(const void *v) { \
+ struct Unaligned { \
+ uint##x##_t i; \
+ } __attribute__((packed)); \
+ \
+ return ((const struct Unaligned *) v)->i; \
+}
+# elif defined(__DECC)
+# define unaligned(x) \
+static inline uint##x##_t unaligned##x(const void *v) { \
+ return *(const __unaligned uint##x##_t *) v; \
+}
+# else
+# define unaligned(x) \
+static inline uint##x##_t unaligned##x(const void *v) { \
+ return *(const uint##x##_t *) v; \
+}
+# endif
+unaligned(16)
+unaligned(32)
+unaligned(64)
+#undef unaligned
+#endif /* defined(ARCH_X86) */
+
+#ifndef ALT_BITSTREAM_WRITER
+static inline void put_bits(PutBitContext *s, int n, unsigned int value)
+{
+ unsigned int bit_buf;
+ int bit_left;
+
+ // printf("put_bits=%d %x\n", n, value);
+ assert(n == 32 || value < (1U << n));
+
+ bit_buf = s->bit_buf;
+ bit_left = s->bit_left;
+
+ // printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
+ /* XXX: optimize */
+ if (n < bit_left) {
+ bit_buf = (bit_buf<<n) | value;
+ bit_left-=n;
+ } else {
+ bit_buf<<=bit_left;
+ bit_buf |= value >> (n - bit_left);
+#ifdef UNALIGNED_STORES_ARE_BAD
+ if (3 & (intptr_t) s->buf_ptr) {
+ s->buf_ptr[0] = bit_buf >> 24;
+ s->buf_ptr[1] = bit_buf >> 16;
+ s->buf_ptr[2] = bit_buf >> 8;
+ s->buf_ptr[3] = bit_buf ;
+ } else
+#endif
+ *(uint32_t *)s->buf_ptr = be2me_32(bit_buf);
+ //printf("bitbuf = %08x\n", bit_buf);
+ s->buf_ptr+=4;
+ bit_left+=32 - n;
+ bit_buf = value;
+ }
+
+ s->bit_buf = bit_buf;
+ s->bit_left = bit_left;
+}
+#endif
+
+
+#ifdef ALT_BITSTREAM_WRITER
+static inline void put_bits(PutBitContext *s, int n, unsigned int value)
+{
+# ifdef ALIGNED_BITSTREAM_WRITER
+# if defined(ARCH_X86)
+ asm volatile(
+ "movl %0, %%ecx \n\t"
+ "xorl %%eax, %%eax \n\t"
+ "shrdl %%cl, %1, %%eax \n\t"
+ "shrl %%cl, %1 \n\t"
+ "movl %0, %%ecx \n\t"
+ "shrl $3, %%ecx \n\t"
+ "andl $0xFFFFFFFC, %%ecx \n\t"
+ "bswapl %1 \n\t"
+ "orl %1, (%2, %%ecx) \n\t"
+ "bswapl %%eax \n\t"
+ "addl %3, %0 \n\t"
+ "movl %%eax, 4(%2, %%ecx) \n\t"
+ : "=&r" (s->index), "=&r" (value)
+ : "r" (s->buf), "r" (n), "0" (s->index), "1" (value<<(-n))
+ : "%eax", "%ecx"
+ );
+# else
+ int index= s->index;
+ uint32_t *ptr= ((uint32_t *)s->buf)+(index>>5);
+
+ value<<= 32-n;
+
+ ptr[0] |= be2me_32(value>>(index&31));
+ ptr[1] = be2me_32(value<<(32-(index&31)));
+//if(n>24) printf("%d %d\n", n, value);
+ index+= n;
+ s->index= index;
+# endif
+# else //ALIGNED_BITSTREAM_WRITER
+# if defined(ARCH_X86)
+ asm volatile(
+ "movl $7, %%ecx \n\t"
+ "andl %0, %%ecx \n\t"
+ "addl %3, %%ecx \n\t"
+ "negl %%ecx \n\t"
+ "shll %%cl, %1 \n\t"
+ "bswapl %1 \n\t"
+ "movl %0, %%ecx \n\t"
+ "shrl $3, %%ecx \n\t"
+ "orl %1, (%%ecx, %2) \n\t"
+ "addl %3, %0 \n\t"
+ "movl $0, 4(%%ecx, %2) \n\t"
+ : "=&r" (s->index), "=&r" (value)
+ : "r" (s->buf), "r" (n), "0" (s->index), "1" (value)
+ : "%ecx"
+ );
+# else
+ int index= s->index;
+ uint32_t *ptr= (uint32_t*)(((uint8_t *)s->buf)+(index>>3));
+
+ ptr[0] |= be2me_32(value<<(32-n-(index&7) ));
+ ptr[1] = 0;
+//if(n>24) printf("%d %d\n", n, value);
+ index+= n;
+ s->index= index;
+# endif
+# endif //!ALIGNED_BITSTREAM_WRITER
+}
+#endif
+
+
+static inline uint8_t* pbBufPtr(PutBitContext *s)
+{
+#ifdef ALT_BITSTREAM_WRITER
+ return s->buf + (s->index>>3);
+#else
+ return s->buf_ptr;
+#endif
+}
+
+/**
+ *
+ * PutBitContext must be flushed & aligned to a byte boundary before calling this.
+ */
+static inline void skip_put_bytes(PutBitContext *s, int n){
+ assert((put_bits_count(s)&7)==0);
+#ifdef ALT_BITSTREAM_WRITER
+ FIXME may need some cleaning of the buffer
+ s->index += n<<3;
+#else
+ assert(s->bit_left==32);
+ s->buf_ptr += n;
+#endif
+}
+
+/**
+ * skips the given number of bits.
+ * must only be used if the actual values in the bitstream dont matter
+ */
+static inline void skip_put_bits(PutBitContext *s, int n){
+#ifdef ALT_BITSTREAM_WRITER
+ s->index += n;
+#else
+ s->bit_left -= n;
+ s->buf_ptr-= s->bit_left>>5;
+ s->bit_left &= 31;
+#endif
+}
+
+/**
+ * Changes the end of the buffer.
+ */
+static inline void set_put_bits_buffer_size(PutBitContext *s, int size){
+ s->buf_end= s->buf + size;
+}
+
+/* Bitstream reader API docs:
+name
+ abritary name which is used as prefix for the internal variables
+
+gb
+ getbitcontext
+
+OPEN_READER(name, gb)
+ loads gb into local variables
+
+CLOSE_READER(name, gb)
+ stores local vars in gb
+
+UPDATE_CACHE(name, gb)
+ refills the internal cache from the bitstream
+ after this call at least MIN_CACHE_BITS will be available,
+
+GET_CACHE(name, gb)
+ will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit)
+
+SHOW_UBITS(name, gb, num)
+ will return the next num bits
+
+SHOW_SBITS(name, gb, num)
+ will return the next num bits and do sign extension
+
+SKIP_BITS(name, gb, num)
+ will skip over the next num bits
+ note, this is equivalent to SKIP_CACHE; SKIP_COUNTER
+
+SKIP_CACHE(name, gb, num)
+ will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER)
+
+SKIP_COUNTER(name, gb, num)
+ will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS)
+
+LAST_SKIP_CACHE(name, gb, num)
+ will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing
+
+LAST_SKIP_BITS(name, gb, num)
+ is equivalent to SKIP_LAST_CACHE; SKIP_COUNTER
+
+for examples see get_bits, show_bits, skip_bits, get_vlc
+*/
+
+static inline int unaligned32_be(const void *v)
+{
+#ifdef CONFIG_ALIGN
+ const uint8_t *p=v;
+ return (((p[0]<<8) | p[1])<<16) | (p[2]<<8) | (p[3]);
+#else
+ return be2me_32( unaligned32(v)); //original
+#endif
+}
+
+static inline int unaligned32_le(const void *v)
+{
+#ifdef CONFIG_ALIGN
+ const uint8_t *p=v;
+ return (((p[3]<<8) | p[2])<<16) | (p[1]<<8) | (p[0]);
+#else
+ return le2me_32( unaligned32(v)); //original
+#endif
+}
+
+#ifdef ALT_BITSTREAM_READER
+# define MIN_CACHE_BITS 25
+
+# define OPEN_READER(name, gb)\
+ int name##_index= (gb)->index;\
+ int name##_cache= 0;\
+
+# define CLOSE_READER(name, gb)\
+ (gb)->index= name##_index;\
+
+# ifdef ALT_BITSTREAM_READER_LE
+# define UPDATE_CACHE(name, gb)\
+ name##_cache= unaligned32_le( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) >> (name##_index&0x07);\
+
+# define SKIP_CACHE(name, gb, num)\
+ name##_cache >>= (num);
+# else
+# define UPDATE_CACHE(name, gb)\
+ name##_cache= unaligned32_be( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07);\
+
+# define SKIP_CACHE(name, gb, num)\
+ name##_cache <<= (num);
+# endif
+
+// FIXME name?
+# define SKIP_COUNTER(name, gb, num)\
+ name##_index += (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_COUNTER(name, gb, num)
+# define LAST_SKIP_CACHE(name, gb, num) ;
+
+# ifdef ALT_BITSTREAM_READER_LE
+# define SHOW_UBITS(name, gb, num)\
+ ((name##_cache) & (NEG_USR32(0xffffffff,num)))
+
+# define SHOW_SBITS(name, gb, num)\
+ NEG_SSR32((name##_cache)<<(32-(num)), num)
+# else
+# define SHOW_UBITS(name, gb, num)\
+ NEG_USR32(name##_cache, num)
+
+# define SHOW_SBITS(name, gb, num)\
+ NEG_SSR32(name##_cache, num)
+# endif
+
+# define GET_CACHE(name, gb)\
+ ((uint32_t)name##_cache)
+
+static inline int get_bits_count(GetBitContext *s){
+ return s->index;
+}
+
+static inline void skip_bits_long(GetBitContext *s, int n){
+ s->index += n;
+}
+
+#elif defined LIBMPEG2_BITSTREAM_READER
+//libmpeg2 like reader
+
+# define MIN_CACHE_BITS 17
+
+# define OPEN_READER(name, gb)\
+ int name##_bit_count=(gb)->bit_count;\
+ int name##_cache= (gb)->cache;\
+ uint8_t * name##_buffer_ptr=(gb)->buffer_ptr;\
+
+# define CLOSE_READER(name, gb)\
+ (gb)->bit_count= name##_bit_count;\
+ (gb)->cache= name##_cache;\
+ (gb)->buffer_ptr= name##_buffer_ptr;\
+
+#ifdef LIBMPEG2_BITSTREAM_READER_HACK
+
+# define UPDATE_CACHE(name, gb)\
+ if(name##_bit_count >= 0){\
+ name##_cache+= (int)be2me_16(*(uint16_t*)name##_buffer_ptr) << name##_bit_count;\
+ name##_buffer_ptr += 2;\
+ name##_bit_count-= 16;\
+ }\
+
+#else
+
+# define UPDATE_CACHE(name, gb)\
+ if(name##_bit_count >= 0){\
+ name##_cache+= ((name##_buffer_ptr[0]<<8) + name##_buffer_ptr[1]) << name##_bit_count;\
+ name##_buffer_ptr+=2;\
+ name##_bit_count-= 16;\
+ }\
+
+#endif
+
+# define SKIP_CACHE(name, gb, num)\
+ name##_cache <<= (num);\
+
+# 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##_cache, num)
+
+# define SHOW_SBITS(name, gb, num)\
+ NEG_SSR32(name##_cache, num)
+
+# define GET_CACHE(name, gb)\
+ ((uint32_t)name##_cache)
+
+static inline int get_bits_count(GetBitContext *s){
+ return (s->buffer_ptr - s->buffer)*8 - 16 + s->bit_count;
+}
+
+static inline void skip_bits_long(GetBitContext *s, int n){
+ OPEN_READER(re, s)
+ re_bit_count += n;
+ re_buffer_ptr += 2*(re_bit_count>>4);
+ re_bit_count &= 15;
+ re_cache = ((re_buffer_ptr[-2]<<8) + re_buffer_ptr[-1]) << (16+re_bit_count);
+ UPDATE_CACHE(re, s)
+ CLOSE_READER(re, s)
+}
+
+#elif defined A32_BITSTREAM_READER
+
+# define MIN_CACHE_BITS 32
+
+# define OPEN_READER(name, gb)\
+ int name##_bit_count=(gb)->bit_count;\
+ uint32_t name##_cache0= (gb)->cache0;\
+ uint32_t name##_cache1= (gb)->cache1;\
+ uint32_t * name##_buffer_ptr=(gb)->buffer_ptr;\
+
+# define CLOSE_READER(name, gb)\
+ (gb)->bit_count= name##_bit_count;\
+ (gb)->cache0= name##_cache0;\
+ (gb)->cache1= name##_cache1;\
+ (gb)->buffer_ptr= name##_buffer_ptr;\
+
+# define UPDATE_CACHE(name, gb)\
+ if(name##_bit_count > 0){\
+ const uint32_t next= be2me_32( *name##_buffer_ptr );\
+ name##_cache0 |= NEG_USR32(next,name##_bit_count);\
+ name##_cache1 |= next<<name##_bit_count;\
+ name##_buffer_ptr++;\
+ name##_bit_count-= 32;\
+ }\
+
+#if defined(ARCH_X86)
+# 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;
+}
+
+static inline void skip_bits_long(GetBitContext *s, int n){
+ OPEN_READER(re, s)
+ re_bit_count += n;
+ re_buffer_ptr += re_bit_count>>5;
+ re_bit_count &= 31;
+ re_cache0 = be2me_32( re_buffer_ptr[-1] ) << re_bit_count;
+ re_cache1 = 0;
+ UPDATE_CACHE(re, s)
+ CLOSE_READER(re, s)
+}
+
+#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 sign;
+ register int32_t cache;
+ OPEN_READER(re, s)
+ UPDATE_CACHE(re, s)
+ cache = GET_CACHE(re,s);
+ sign=(~cache)>>31;
+ LAST_SKIP_BITS(re, s, n)
+ CLOSE_READER(re, s)
+ return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
+}
+
+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 1-17 bits.
+ * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
+ */
+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;
+}
+
+/**
+ * shows 1-17 bits.
+ * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
+ */
+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;
+}
+
+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 ];
+#ifdef ALT_BITSTREAM_READER_LE
+ result>>= (index&0x07);
+ result&= 1;
+#else
+ result<<= (index&0x07);
+ result>>= 8 - 1;
+#endif
+ 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);
+}
+
+/**
+ * reads 0-32 bits.
+ */
+static inline unsigned int get_bits_long(GetBitContext *s, int n){
+ if(n<=17) return get_bits(s, n);
+ else{
+#ifdef ALT_BITSTREAM_READER_LE
+ int ret= get_bits(s, 16);
+ return ret | (get_bits(s, n-16) << 16);
+#else
+ int ret= get_bits(s, 16) << (n-16);
+ return ret | get_bits(s, n-16);
+#endif
+ }
+}
+
+/**
+ * shows 0-32 bits.
+ */
+static inline unsigned int show_bits_long(GetBitContext *s, int n){
+ if(n<=17) return show_bits(s, n);
+ else{
+ GetBitContext gb= *s;
+ int ret= get_bits_long(s, n);
+ *s= gb;
+ return ret;
+ }
+}
+
+static inline int check_marker(GetBitContext *s, const char *msg)
+{
+ int bit= get_bits1(s);
+ if(!bit)
+ av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg);
+
+ return bit;
+}
+
+/**
+ * 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)
+{
+ int buffer_size= (bit_size+7)>>3;
+ if(buffer_size < 0 || bit_size < 0) {
+ buffer_size = bit_size = 0;
+ buffer = NULL;
+ }
+
+ 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
+ s->buffer_ptr = (uint8_t*)((intptr_t)buffer&(~1));
+ s->bit_count = 16 + 8*((intptr_t)buffer&1);
+ skip_bits_long(s, 0);
+#elif defined A32_BITSTREAM_READER
+ s->buffer_ptr = (uint32_t*)((intptr_t)buffer&(~3));
+ s->bit_count = 32 + 8*((intptr_t)buffer&3);
+ skip_bits_long(s, 0);
+#endif
+}
+
+static inline void align_get_bits(GetBitContext *s)
+{
+ int n= (-get_bits_count(s)) & 7;
+ if(n) skip_bits(s, n);
+}
+
+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 flags);
+#define INIT_VLC_USE_STATIC 1
+#define INIT_VLC_LE 2
+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, need_update)\
+{\
+ 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){\
+ SKIP_BITS(name, gb, bits)\
+ if(need_update){\
+ 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)\
+}
+
+
+/**
+ * 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 av_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
+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(p, ...) av_log(p, AV_LOG_DEBUG, __VA_ARGS__)
+
+#else //TRACE
+#define tprintf(p, ...) {}
+#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 */
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-26 18:33:58 +0000