common.c -> bitstream.c (and the single non bitstream func -> utils.c)

common.h -> common.h/bitstream.h

Originally committed as revision 3777 to svn://svn.ffmpeg.org/ffmpeg/trunk

17 files changed, 867 insertions, 845 deletions

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 67e6a30ff6..1b41354087 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -9,7 +9,7 @@ VPATH=$(SRC_PATH)/libavcodec
 # NOTE: -I.. is needed to include config.h
 CFLAGS=$(OPTFLAGS) -DHAVE_AV_CONFIG_H -I.. -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_GNU_SOURCE
 
-OBJS= common.o utils.o mem.o allcodecs.o \
+OBJS= bitstream.o utils.o mem.o allcodecs.o \
       mpegvideo.o jrevdct.o jfdctfst.o jfdctint.o\
       mpegaudio.o ac3enc.o mjpeg.o resample.o resample2.o dsputil.o \
       motion_est.o imgconvert.o imgresample.o \
diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c
index eb9c8577a1..b690e1c359 100644
--- a/libavcodec/ac3enc.c
+++ b/libavcodec/ac3enc.c
@@ -24,7 +24,7 @@
 //#define DEBUG
 //#define DEBUG_BITALLOC
 #include "avcodec.h"
-
+#include "bitstream.h"
 #include "ac3.h"
 
 typedef struct AC3EncodeContext {
diff --git a/libavcodec/common.c b/libavcodec/bitstream.c
index 902d5e728d..2678772c49 100644
--- a/libavcodec/common.c
+++ b/libavcodec/bitstream.c
@@ -21,29 +21,12 @@
  */
 
 /**
- * @file common.c
- * common internal api.
+ * @file bitstream.c
+ * bitstream api.
  */
-
+ 
 #include "avcodec.h"
-
-const uint8_t ff_sqrt_tab[128]={
-        0, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
-        5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
-        8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
-        9, 9, 9, 9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,11,11,11,11,11,11,11
-};
-
-const uint8_t ff_log2_tab[256]={
-        0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
-        5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
-        6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
-        6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
-        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
-        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
-        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
-        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
-};
+#include "bitstream.h"
 
 void align_put_bits(PutBitContext *s)
 {
@@ -302,7 +285,3 @@ void free_vlc(VLC *vlc)
     av_free(vlc->table);
 }
 
-int64_t ff_gcd(int64_t a, int64_t b){
-    if(b) return ff_gcd(b, a%b);
-    else  return a;
-}
diff --git a/libavcodec/bitstream.h b/libavcodec/bitstream.h
new file mode 100644
index 0000000000..9614f7728e
--- /dev/null
+++ b/libavcodec/bitstream.h
@@ -0,0 +1,827 @@
+/**
+ * @file bitstream.h
+ * bitstream api header.
+ */
+
+#ifndef BITSTREAM_H
+#define BITSTREAM_H
+
+//#define ALT_BITSTREAM_WRITER
+//#define ALIGNED_BITSTREAM_WRITER
+
+#define ALT_BITSTREAM_READER
+//#define LIBMPEG2_BITSTREAM_READER
+//#define A32_BITSTREAM_READER
+#define LIBMPEG2_BITSTREAM_READER_HACK //add BERO
+ 
+#if defined(ARCH_X86) || defined(ARCH_X86_64)
+// 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)
+{
+    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 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;
+
+#ifdef ARCH_SPARC
+#define UNALIGNED_STORES_ARE_BAD
+#endif
+
+/* used to avoid missaligned exceptions on some archs (alpha, ...) */
+#if defined(ARCH_X86) || defined(ARCH_X86_64)
+#    define unaligned32(a) (*(const uint32_t*)(a))
+#else
+#    ifdef __GNUC__
+static inline uint32_t unaligned32(const void *v) {
+    struct Unaligned {
+	uint32_t i;
+    } __attribute__((packed));
+
+    return ((const struct Unaligned *) v)->i;
+}
+#    elif defined(__DECC)
+static inline uint32_t unaligned32(const void *v) {
+    return *(const __unaligned uint32_t *) v;
+}
+#    else
+static inline uint32_t unaligned32(const void *v) {
+    return *(const uint32_t *) v;
+}
+#    endif
+#endif //!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;
+
+#ifdef STATS
+    st_out_bit_counts[st_current_index] += n;
+#endif
+    //    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) || defined(ARCH_X86_64)
+    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) || defined(ARCH_X86_64)
+    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    
+}
+
+/**
+ * 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 nest num bits
+
+SHOW_SBITS(name, gb, num)
+    will return the nest num bits and do sign extension
+
+SKIP_BITS(name, gb, num)
+    will skip over the next num bits
+    note, this is equinvalent 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 equinvalent 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
+}
+
+#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;\
+
+#   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);\
+
+// 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) ;
+
+#   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->index;
+}
+#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;\
+        ((uint16_t*)name##_buffer_ptr)++;\
+        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;
+}
+
+#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) || 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
+
+static inline void print_bin(int bits, int n){
+    int i;
+    
+    for(i=n-1; i>=0; i--){
+        printf("%d", (bits>>i)&1);
+    }
+    for(i=n; i<24; i++)
+        printf(" ");
+}
+
+static inline int get_bits_trace(GetBitContext *s, int n, char *file, char *func, int line){
+    int r= get_bits(s, n);
+    
+    print_bin(r, n);
+    printf("%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, 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);
+    
+    printf("%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, char *func, int line){
+    int show= show_bits(s, n);
+    int r= get_xbits(s, n);
+    
+    print_bin(show, n);
+    printf("%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
+
+#endif /* BITSTREAM_H */
diff --git a/libavcodec/cabac.c b/libavcodec/cabac.c
index 915c057114..c16fb162e0 100644
--- a/libavcodec/cabac.c
+++ b/libavcodec/cabac.c
@@ -26,6 +26,7 @@
 #include <string.h>
 
 #include "common.h"
+#include "bitstream.h"
 #include "cabac.h"
 
 const uint8_t ff_h264_lps_range[64][4]= {
diff --git a/libavcodec/common.h b/libavcodec/common.h
index 619719a6f3..5b59def89f 100644
--- a/libavcodec/common.h
+++ b/libavcodec/common.h
@@ -10,14 +10,6 @@
 #    define CONFIG_WIN32
 #endif
 
-//#define ALT_BITSTREAM_WRITER
-//#define ALIGNED_BITSTREAM_WRITER
-
-#define ALT_BITSTREAM_READER
-//#define LIBMPEG2_BITSTREAM_READER
-//#define A32_BITSTREAM_READER
-#define LIBMPEG2_BITSTREAM_READER_HACK //add BERO
-
 #ifndef M_PI
 #define M_PI    3.14159265358979323846
 #endif
@@ -292,816 +284,6 @@ extern const uint32_t inverse[256];
 #    define FASTDIV(a,b)   ((a)/(b))
 #endif
  
-#if defined(ARCH_X86) || defined(ARCH_X86_64)
-// 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)
-{
-    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 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;
-
-#ifdef ARCH_SPARC
-#define UNALIGNED_STORES_ARE_BAD
-#endif
-
-/* used to avoid missaligned exceptions on some archs (alpha, ...) */
-#if defined(ARCH_X86) || defined(ARCH_X86_64)
-#    define unaligned32(a) (*(const uint32_t*)(a))
-#else
-#    ifdef __GNUC__
-static inline uint32_t unaligned32(const void *v) {
-    struct Unaligned {
-	uint32_t i;
-    } __attribute__((packed));
-
-    return ((const struct Unaligned *) v)->i;
-}
-#    elif defined(__DECC)
-static inline uint32_t unaligned32(const void *v) {
-    return *(const __unaligned uint32_t *) v;
-}
-#    else
-static inline uint32_t unaligned32(const void *v) {
-    return *(const uint32_t *) v;
-}
-#    endif
-#endif //!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;
-
-#ifdef STATS
-    st_out_bit_counts[st_current_index] += n;
-#endif
-    //    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) || defined(ARCH_X86_64)
-    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) || defined(ARCH_X86_64)
-    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    
-}
-
-/**
- * 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 nest num bits
-
-SHOW_SBITS(name, gb, num)
-    will return the nest num bits and do sign extension
-
-SKIP_BITS(name, gb, num)
-    will skip over the next num bits
-    note, this is equinvalent 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 equinvalent 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
-}
-
-#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;\
-
-#   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);\
-
-// 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) ;
-
-#   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->index;
-}
-#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;\
-        ((uint16_t*)name##_buffer_ptr)++;\
-        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;
-}
-
-#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) || 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
-
-static inline void print_bin(int bits, int n){
-    int i;
-    
-    for(i=n-1; i>=0; i--){
-        printf("%d", (bits>>i)&1);
-    }
-    for(i=n; i<24; i++)
-        printf(" ");
-}
-
-static inline int get_bits_trace(GetBitContext *s, int n, char *file, char *func, int line){
-    int r= get_bits(s, n);
-    
-    print_bin(r, n);
-    printf("%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, 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);
-    
-    printf("%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, char *func, int line){
-    int show= show_bits(s, n);
-    int r= get_xbits(s, n);
-    
-    print_bin(show, n);
-    printf("%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
-
 /* define it to include statistics code (useful only for optimizing
    codec efficiency */
 //#define STATS
diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
index 991a8b3c05..b9d2806b88 100644
--- a/libavcodec/ffv1.c
+++ b/libavcodec/ffv1.c
@@ -25,6 +25,7 @@
  */
 
 #include "common.h"
+#include "bitstream.h"
 #include "avcodec.h"
 #include "dsputil.h"
 #include "rangecoder.h"
diff --git a/libavcodec/flac.c b/libavcodec/flac.c
index 9ccffe7f1e..3de62bed2f 100644
--- a/libavcodec/flac.c
+++ b/libavcodec/flac.c
@@ -34,6 +34,7 @@
 #include <limits.h>
  
 #include "avcodec.h"
+#include "bitstream.h"
 #include "golomb.h"
 
 #undef NDEBUG
diff --git a/libavcodec/g726.c b/libavcodec/g726.c
index fdce022b93..bc9374d3e6 100644
--- a/libavcodec/g726.c
+++ b/libavcodec/g726.c
@@ -22,6 +22,7 @@
 #include <limits.h>
 #include "avcodec.h"
 #include "common.h"
+#include "bitstream.h"
 
 /**
  * G.726 11bit float.
diff --git a/libavcodec/huffyuv.c b/libavcodec/huffyuv.c
index 66a3df169d..e8a9ffa86d 100644
--- a/libavcodec/huffyuv.c
+++ b/libavcodec/huffyuv.c
@@ -27,6 +27,7 @@
  */
 
 #include "common.h"
+#include "bitstream.h"
 #include "avcodec.h"
 #include "dsputil.h"
 
diff --git a/libavcodec/lcl.c b/libavcodec/lcl.c
index b536ac0be1..16225bb29b 100644
--- a/libavcodec/lcl.c
+++ b/libavcodec/lcl.c
@@ -41,6 +41,7 @@
 #include <stdlib.h>
 
 #include "common.h"
+#include "bitstream.h"
 #include "avcodec.h"
 
 #ifdef CONFIG_ZLIB
diff --git a/libavcodec/mpegaudio.c b/libavcodec/mpegaudio.c
index b0b5d68b60..e4b2576356 100644
--- a/libavcodec/mpegaudio.c
+++ b/libavcodec/mpegaudio.c
@@ -23,6 +23,7 @@
  */
  
 #include "avcodec.h"
+#include "bitstream.h"
 #include "mpegaudio.h"
 
 /* currently, cannot change these constants (need to modify
diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c
index a1eadcbbda..0ff5fcbb98 100644
--- a/libavcodec/mpegaudiodec.c
+++ b/libavcodec/mpegaudiodec.c
@@ -24,6 +24,7 @@
 
 //#define DEBUG
 #include "avcodec.h"
+#include "bitstream.h"
 #include "mpegaudio.h"
 #include "dsputil.h"
 
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index 0aeb07a198..49682952ac 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -27,6 +27,7 @@
 #define AVCODEC_MPEGVIDEO_H
 
 #include "dsputil.h"
+#include "bitstream.h"
 
 #define FRAME_SKIPED 100 ///< return value for header parsers if frame is not coded
 
diff --git a/libavcodec/sonic.c b/libavcodec/sonic.c
index 615d8752bb..3981f3bd7d 100644
--- a/libavcodec/sonic.c
+++ b/libavcodec/sonic.c
@@ -17,6 +17,7 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 #include "avcodec.h"
+#include "bitstream.h"
 #include "golomb.h"
 
 /**
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index d87ed6e139..f11d22e590 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -31,6 +31,24 @@
 #include <stdarg.h>
 #include <limits.h>
 
+const uint8_t ff_sqrt_tab[128]={
+        0, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
+        5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+        8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+        9, 9, 9, 9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,11,11,11,11,11,11,11
+};
+
+const uint8_t ff_log2_tab[256]={
+        0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
+        5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+        6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+        6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+        7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
+};
+
 void avcodec_default_free_buffers(AVCodecContext *s);
 
 void *av_mallocz(unsigned int size)
@@ -881,6 +899,11 @@ int64_t av_rescale(int64_t a, int64_t b, int64_t c){
     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
 }
 
+int64_t ff_gcd(int64_t a, int64_t b){
+    if(b) return ff_gcd(b, a%b);
+    else  return a;
+}
+
 /* av_log API */
 
 static int av_log_level = AV_LOG_DEBUG;
diff --git a/libavcodec/wmadec.c b/libavcodec/wmadec.c
index cc83f4f823..e0788375fa 100644
--- a/libavcodec/wmadec.c
+++ b/libavcodec/wmadec.c
@@ -32,6 +32,7 @@
  */
 
 #include "avcodec.h"
+#include "bitstream.h"
 #include "dsputil.h"
 
 /* size of blocks */