[SCM] libav/experimental: new bitstream reader API (old get_bits() based one is emulated and will still be supported in the future cuz its simpler) minor optimizations to get_vlc
siretart at users.alioth.debian.org
siretart at users.alioth.debian.org
Sun Jun 30 15:32:39 UTC 2013
The following commit has been merged in the experimental branch:
commit 8db1a1dde0f61f98e9e69707eb10601e42ad3a34
Author: Michael Niedermayer <michaelni at gmx.at>
Date: Tue Jul 9 10:35:10 2002 +0000
new bitstream reader API (old get_bits() based one is emulated and will still be supported in the future cuz its simpler)
minor optimizations to get_vlc
Originally committed as revision 725 to svn://svn.ffmpeg.org/ffmpeg/trunk
diff --git a/libavcodec/common.c b/libavcodec/common.c
index 571de1a..32edf9a 100644
--- a/libavcodec/common.c
+++ b/libavcodec/common.c
@@ -118,101 +118,39 @@ void put_string(PutBitContext * pbc, char *s)
/* bit input functions */
-void init_get_bits(GetBitContext *s,
+void init_get_bits(GetBitContext *s,
UINT8 *buffer, int buffer_size)
{
-#ifdef ALT_BITSTREAM_READER
- s->index=0;
s->buffer= buffer;
-#else
- s->buf = buffer;
- s->buf_ptr = buffer;
- s->buf_end = buffer + buffer_size;
- s->bit_cnt = 0;
- s->bit_buf = 0;
- while (s->buf_ptr < s->buf_end &&
- s->bit_cnt < 32) {
- s->bit_buf |= (*s->buf_ptr++ << (24 - s->bit_cnt));
- s->bit_cnt += 8;
- }
-#endif
s->size= buffer_size;
-}
-
-#ifndef ALT_BITSTREAM_READER
-/* n must be >= 1 and <= 32 */
-/* also true: n > s->bit_cnt */
-unsigned int get_bits_long(GetBitContext *s, int n)
-{
- unsigned int val;
- int bit_cnt;
- unsigned int bit_buf;
-
-#ifdef STATS
- st_bit_counts[st_current_index] += n;
+ s->buffer_end= buffer + buffer_size;
+#ifdef ALT_BITSTREAM_READER
+ s->index=0;
+#elif defined LIBMPEG2_BITSTREAM_READER
+ 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
-
- bit_buf = s->bit_buf;
- bit_cnt = s->bit_cnt - n;
-
-// if (bit_cnt >= 0) {
-// val = bit_buf >> (32 - n);
-// bit_buf <<= n;
-// } else
{
- UINT8 *buf_ptr;
- val = bit_buf >> (32 - n);
- buf_ptr = s->buf_ptr;
- buf_ptr += 4;
- /* handle common case: we can read everything */
- if (buf_ptr <= s->buf_end) {
-#ifdef ARCH_X86
- bit_buf = bswap_32(*((unsigned long*)(&buf_ptr[-4])));
-#else
- bit_buf = (buf_ptr[-4] << 24) |
- (buf_ptr[-3] << 16) |
- (buf_ptr[-2] << 8) |
- (buf_ptr[-1]);
-#endif
- val |= bit_buf >> (32 + bit_cnt);
- bit_buf <<= - bit_cnt;
- bit_cnt += 32;
- } else {
- buf_ptr -= 4;
- bit_buf = 0;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++ << 24;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++ << 16;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++ << 8;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++;
-
- val |= bit_buf >> (32 + bit_cnt);
- bit_buf <<= - bit_cnt;
- bit_cnt += 8*(buf_ptr - s->buf_ptr);
- if(bit_cnt<0) bit_cnt=0;
- }
- s->buf_ptr = buf_ptr;
+ OPEN_READER(re, s)
+ UPDATE_CACHE(re, s)
+// UPDATE_CACHE(re, s)
+ CLOSE_READER(re, s)
}
- s->bit_buf = bit_buf;
- s->bit_cnt = bit_cnt;
- return val;
-}
+#ifdef A32_BITSTREAM_READER
+ s->cache1 = 0;
#endif
+}
void align_get_bits(GetBitContext *s)
{
-#ifdef ALT_BITSTREAM_READER
- s->index= (s->index + 7) & (~7);
-#else
- int n;
- n = s->bit_cnt & 7;
- if (n > 0) {
- get_bits(s, n);
- }
-#endif
+ int n= (-get_bits_count(s)) & 7;
+ if(n) skip_bits(s, n);
}
int check_marker(GetBitContext *s, char *msg)
@@ -223,55 +161,6 @@ int check_marker(GetBitContext *s, char *msg)
return bit;
}
-#ifndef ALT_BITSTREAM_READER
-/* This function is identical to get_bits_long(), the */
-/* only diference is that it doesn't touch the buffer */
-/* it is usefull to see the buffer. */
-
-unsigned int show_bits_long(GetBitContext *s, int n)
-{
- unsigned int val;
- int bit_cnt;
- unsigned int bit_buf;
- UINT8 *buf_ptr;
-
- bit_buf = s->bit_buf;
- bit_cnt = s->bit_cnt - n;
-
- val = bit_buf >> (32 - n);
- buf_ptr = s->buf_ptr;
- buf_ptr += 4;
-
- /* handle common case: we can read everything */
- if (buf_ptr <= s->buf_end) {
-#ifdef ARCH_X86
- bit_buf = bswap_32(*((unsigned long*)(&buf_ptr[-4])));
-#else
- bit_buf = (buf_ptr[-4] << 24) |
- (buf_ptr[-3] << 16) |
- (buf_ptr[-2] << 8) |
- (buf_ptr[-1]);
-#endif
- } else {
- buf_ptr -= 4;
- bit_buf = 0;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++ << 24;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++ << 16;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++ << 8;
- if (buf_ptr < s->buf_end)
- bit_buf |= *buf_ptr++;
- }
- val |= bit_buf >> (32 + bit_cnt);
- bit_buf <<= - bit_cnt;
- bit_cnt += 32;
-
- return val;
-}
-#endif
-
/* VLC decoding */
//#define DEBUG_VLC
@@ -300,18 +189,15 @@ static int alloc_table(VLC *vlc, int size)
vlc->table_size += size;
if (vlc->table_size > vlc->table_allocated) {
vlc->table_allocated += (1 << vlc->bits);
- vlc->table_bits = realloc(vlc->table_bits,
- sizeof(INT8) * vlc->table_allocated);
- vlc->table_codes = realloc(vlc->table_codes,
- sizeof(INT16) * vlc->table_allocated);
- if (!vlc->table_bits ||
- !vlc->table_codes)
+ vlc->table = realloc(vlc->table,
+ sizeof(VLC_TYPE) * 2 * vlc->table_allocated);
+ if (!vlc->table)
return -1;
}
return index;
}
-static int build_table(VLC *vlc, int table_nb_bits,
+static int build_table(VLC *vlc, int table_nb_bits,
int nb_codes,
const void *bits, int bits_wrap, int bits_size,
const void *codes, int codes_wrap, int codes_size,
@@ -319,23 +205,21 @@ static int build_table(VLC *vlc, int table_nb_bits,
{
int i, j, k, n, table_size, table_index, nb, n1, index;
UINT32 code;
- INT8 *table_bits;
- INT16 *table_codes;
+ VLC_TYPE (*table)[2];
table_size = 1 << table_nb_bits;
table_index = alloc_table(vlc, table_size);
#ifdef DEBUG_VLC
- printf("new table index=%d size=%d code_prefix=%x n=%d\n",
+ printf("new table index=%d size=%d code_prefix=%x n=%d\n",
table_index, table_size, code_prefix, n_prefix);
#endif
if (table_index < 0)
return -1;
- table_bits = &vlc->table_bits[table_index];
- table_codes = &vlc->table_codes[table_index];
+ table = &vlc->table[table_index];
for(i=0;i<table_size;i++) {
- table_bits[i] = 0;
- table_codes[i] = -1;
+ table[i][1] = 0; //bits
+ table[i][0] = -1; //codes
}
/* first pass: map codes and compute auxillary table sizes */
@@ -360,12 +244,12 @@ static int build_table(VLC *vlc, int table_nb_bits,
printf("%4x: code=%d n=%d\n",
j, i, n);
#endif
- if (table_bits[j] != 0) {
+ if (table[j][1] /*bits*/ != 0) {
fprintf(stderr, "incorrect codes\n");
exit(1);
}
- table_bits[j] = n;
- table_codes[j] = i;
+ table[j][1] = n; //bits
+ table[j][0] = i; //code
j++;
}
} else {
@@ -376,22 +260,22 @@ static int build_table(VLC *vlc, int table_nb_bits,
j, n);
#endif
/* compute table size */
- n1 = -table_bits[j];
+ n1 = -table[j][1]; //bits
if (n > n1)
n1 = n;
- table_bits[j] = -n1;
+ table[j][1] = -n1; //bits
}
}
}
/* second pass : fill auxillary tables recursively */
for(i=0;i<table_size;i++) {
- n = table_bits[i];
+ n = table[i][1]; //bits
if (n < 0) {
n = -n;
if (n > table_nb_bits) {
n = table_nb_bits;
- table_bits[i] = -n;
+ table[i][1] = -n; //bits
}
index = build_table(vlc, n, nb_codes,
bits, bits_wrap, bits_size,
@@ -401,9 +285,8 @@ static int build_table(VLC *vlc, int table_nb_bits,
if (index < 0)
return -1;
/* note: realloc has been done, so reload tables */
- table_bits = &vlc->table_bits[table_index];
- table_codes = &vlc->table_codes[table_index];
- table_codes[i] = index;
+ table = &vlc->table[table_index];
+ table[i][0] = index; //code
}
}
return table_index;
@@ -436,8 +319,7 @@ int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
const void *codes, int codes_wrap, int codes_size)
{
vlc->bits = nb_bits;
- vlc->table_bits = NULL;
- vlc->table_codes = NULL;
+ vlc->table = NULL;
vlc->table_allocated = 0;
vlc->table_size = 0;
#ifdef DEBUG_VLC
@@ -448,8 +330,7 @@ int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
bits, bits_wrap, bits_size,
codes, codes_wrap, codes_size,
0, 0) < 0) {
- av_free(vlc->table_bits);
- av_free(vlc->table_codes);
+ av_free(vlc->table);
return -1;
}
return 0;
@@ -458,8 +339,7 @@ int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
void free_vlc(VLC *vlc)
{
- av_free(vlc->table_bits);
- av_free(vlc->table_codes);
+ av_free(vlc->table);
}
int ff_gcd(int a, int b){
diff --git a/libavcodec/common.h b/libavcodec/common.h
index 9f2102a..8ad8a8e 100644
--- a/libavcodec/common.h
+++ b/libavcodec/common.h
@@ -11,13 +11,17 @@
//#define ALT_BITSTREAM_WRITER
//#define ALIGNED_BITSTREAM_WRITER
+#define ALT_BITSTREAM_READER
+//#define LIBMPEG2_BITSTREAM_READER
+//#define A32_BITSTREAM_READER
+
#ifdef ARCH_ALPHA
#define ALT_BITSTREAM_READER
#endif
//#define ALIGNED_BITSTREAM
#define FAST_GET_FIRST_VLC
-//#define DUMP_STREAM // only works with the ALT_BITSTREAM_READER
+//#define DUMP_STREAM
#ifdef HAVE_AV_CONFIG_H
/* only include the following when compiling package */
@@ -161,6 +165,13 @@ inline void dprintf(const char* fmt,...) {}
#define MAX(a,b) ((a) > (b) ? (a) : (b))
#define MIN(a,b) ((a) > (b) ? (b) : (a))
+#ifdef ARCH_X86
+// inverse for shift optimization (gcc should do that ...)
+#define INV32(a) (-a)
+#else
+#define INV32(a) (32-a)
+#endif
+
/* bit output */
struct PutBitContext;
@@ -195,23 +206,29 @@ void jflush_put_bits(PutBitContext *s);
/* bit input */
typedef struct GetBitContext {
+ UINT8 *buffer, *buffer_end;
#ifdef ALT_BITSTREAM_READER
int index;
- UINT8 *buffer;
-#else
- UINT32 bit_buf;
- int bit_cnt;
- UINT8 *buf, *buf_ptr, *buf_end;
+#elif defined LIBMPEG2_BITSTREAM_READER
+ UINT8 *buffer_ptr;
+ UINT32 cache;
+ int bit_count;
+#elif defined A32_BITSTREAM_READER
+ UINT32 *buffer_ptr;
+ UINT32 cache0;
+ UINT32 cache1;
+ int bit_count;
#endif
int size;
} GetBitContext;
static inline int get_bits_count(GetBitContext *s);
+#define VLC_TYPE INT16
+
typedef struct VLC {
int bits;
- INT16 *table_codes;
- INT8 *table_bits;
+ VLC_TYPE (*table)[2]; // code, bits
int table_size, table_allocated;
} VLC;
@@ -438,227 +455,262 @@ static inline uint8_t* pbBufPtr(PutBitContext *s)
#endif
}
-void init_get_bits(GetBitContext *s,
- UINT8 *buffer, int buffer_size);
+/* Bitstream reader API docs:
+name
+ abritary name which is used as prefix for the internal variables
-#ifndef ALT_BITSTREAM_READER
-unsigned int get_bits_long(GetBitContext *s, int n);
-unsigned int show_bits_long(GetBitContext *s, int n);
-#endif
+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 unsigned int get_bits(GetBitContext *s, int n){
#ifdef ALT_BITSTREAM_READER
-#ifdef ALIGNED_BITSTREAM
- int index= s->index;
- uint32_t result1= be2me_32( ((uint32_t *)s->buffer)[index>>5] );
- uint32_t result2= be2me_32( ((uint32_t *)s->buffer)[(index>>5) + 1] );
-#ifdef ARCH_X86
- asm ("shldl %%cl, %2, %0\n\t"
- : "=r" (result1)
- : "0" (result1), "r" (result2), "c" (index));
-#else
- result1<<= (index&0x1F);
- result2= (result2>>1) >> (31-(index&0x1F));
- result1|= result2;
-#endif
- result1>>= 32 - n;
- index+= n;
- s->index= index;
-
- return result1;
-#else //ALIGNED_BITSTREAM
- int index= s->index;
- uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buffer)+(index>>3) ) );
+# define MIN_CACHE_BITS 25
- result<<= (index&0x07);
- result>>= 32 - n;
- index+= n;
- s->index= index;
-#ifdef DUMP_STREAM
- while(n){
- printf("%d", (result>>(n-1))&1);
- n--;
- }
- printf(" ");
-#endif
- return result;
-#endif //!ALIGNED_BITSTREAM
-#else //ALT_BITSTREAM_READER
- if(s->bit_cnt>=n){
- /* most common case here */
- unsigned int val = s->bit_buf >> (32 - n);
- s->bit_buf <<= n;
- s->bit_cnt -= n;
-#ifdef STATS
- st_bit_counts[st_current_index] += n;
-#endif
- return val;
- }
- return get_bits_long(s,n);
-#endif //!ALT_BITSTREAM_READER
+# 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= be2me_32( unaligned32( ((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)\
+ (((uint32_t)name##_cache)>>INV32(num))
+
+# define SHOW_SBITS(name, gb, num)\
+ (((int32_t)name##_cache)>>INV32(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 16
+
+# 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;\
+
+# 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;\
+ }\
-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;
-
-#ifdef DUMP_STREAM
- printf("%d ", result);
-#endif
- return result;
-#else
- if(s->bit_cnt>0){
- /* most common case here */
- unsigned int val = s->bit_buf >> 31;
- s->bit_buf <<= 1;
- s->bit_cnt--;
-#ifdef STATS
- st_bit_counts[st_current_index]++;
-#endif
- return val;
- }
- return get_bits_long(s,1);
-#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)\
+ (((uint32_t)name##_cache)>>INV32(num))
+
+# define SHOW_SBITS(name, gb, num)\
+ (((int32_t)name##_cache)>>INV32(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;
}
-/* This function is identical to get_bits(), the only */
-/* diference is that it doesn't touch the buffer */
-/* it is usefull to see the buffer. */
-static inline unsigned int show_bits(GetBitContext *s, int n)
-{
-#ifdef ALT_BITSTREAM_READER
-#ifdef ALIGNED_BITSTREAM
- int index= s->index;
- uint32_t result1= be2me_32( ((uint32_t *)s->buffer)[index>>5] );
- uint32_t result2= be2me_32( ((uint32_t *)s->buffer)[(index>>5) + 1] );
+#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 |= next>>INV32(name##_bit_count);\
+ name##_cache1 |= next<<name##_bit_count;\
+ name##_buffer_ptr++;\
+ name##_bit_count-= 32;\
+ }\
+
#ifdef ARCH_X86
- asm ("shldl %%cl, %2, %0\n\t"
- : "=r" (result1)
- : "0" (result1), "r" (result2), "c" (index));
+# 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
- result1<<= (index&0x1F);
- result2= (result2>>1) >> (31-(index&0x1F));
- result1|= result2;
+# define SKIP_CACHE(name, gb, num)\
+ name##_cache0 <<= (num);\
+ name##_cache0 |= name##_cache1 >>INV32(num);\
+ name##_cache1 <<= (num);
#endif
- result1>>= 32 - n;
-
- return result1;
-#else //ALIGNED_BITSTREAM
- int index= s->index;
- uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buffer)+(index>>3) ) );
- result<<= (index&0x07);
- result>>= 32 - n;
-
- return result;
-#endif //!ALIGNED_BITSTREAM
-#else //ALT_BITSTREAM_READER
- if(s->bit_cnt>=n) {
- /* most common case here */
- unsigned int val = s->bit_buf >> (32 - n);
- return val;
- }
- return show_bits_long(s,n);
-#endif //!ALT_BITSTREAM_READER
+# 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)\
+ (((uint32_t)name##_cache0)>>INV32(num))
+
+# define SHOW_SBITS(name, gb, num)\
+ (((int32_t)name##_cache0)>>INV32(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 int show_aligned_bits(GetBitContext *s, int offset, int n)
-{
-#ifdef ALT_BITSTREAM_READER
-#ifdef ALIGNED_BITSTREAM
- int index= (s->index + offset + 7)&(~7);
- uint32_t result1= be2me_32( ((uint32_t *)s->buffer)[index>>5] );
- uint32_t result2= be2me_32( ((uint32_t *)s->buffer)[(index>>5) + 1] );
-#ifdef ARCH_X86
- asm ("shldl %%cl, %2, %0\n\t"
- : "=r" (result1)
- : "0" (result1), "r" (result2), "c" (index));
-#else
- result1<<= (index&0x1F);
- result2= (result2>>1) >> (31-(index&0x1F));
- result1|= result2;
#endif
- result1>>= 32 - n;
-
- return result1;
-#else //ALIGNED_BITSTREAM
- int index= (s->index + offset + 7)>>3;
- uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buffer)+index ) );
- result>>= 32 - n;
-
- return result;
-#endif //!ALIGNED_BITSTREAM
-#else //ALT_BITSTREAM_READER
- int index= (get_bits_count(s) + offset + 7)>>3;
- uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buf)+index ) );
+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;
+}
- result>>= 32 - n;
-//printf(" %X %X %d \n", (int)(((uint8_t *)s->buf)+index ), (int)s->buf_ptr, s->bit_cnt);
- return result;
-#endif //!ALT_BITSTREAM_READER
+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
- s->index+= n;
-#ifdef DUMP_STREAM
- {
- int result;
- s->index-= n;
- result= get_bits(s, n);
- }
-#endif
+ int index= s->index;
+ uint8_t result= s->buffer[ index>>3 ];
+ result<<= (index&0x07);
+ result>>= 8 - 1;
+ index++;
+ s->index= index;
+ return result;
#else
- if(s->bit_cnt>=n){
- /* most common case here */
- s->bit_buf <<= n;
- s->bit_cnt -= n;
-#ifdef STATS
- st_bit_counts[st_current_index] += n;
-#endif
- } else {
- get_bits_long(s,n);
- }
+ return get_bits(s, 1);
#endif
}
-static inline void skip_bits1(GetBitContext *s){
-#ifdef ALT_BITSTREAM_READER
- s->index++;
-#ifdef DUMP_STREAM
- s->index--;
- printf("%d ", get_bits1(s));
-#endif
-#else
- if(s->bit_cnt>0){
- /* most common case here */
- s->bit_buf <<= 1;
- s->bit_cnt--;
-#ifdef STATS
- st_bit_counts[st_current_index]++;
-#endif
- } else {
- get_bits_long(s,1);
- }
-#endif
+static inline unsigned int show_bits1(GetBitContext *s){
+ return show_bits(s, 1);
}
-static inline int get_bits_count(GetBitContext *s)
-{
-#ifdef ALT_BITSTREAM_READER
- return s->index;
-#else
- return (s->buf_ptr - s->buf) * 8 - s->bit_cnt;
-#endif
+static inline void skip_bits1(GetBitContext *s){
+ skip_bits(s, 1);
}
+void init_get_bits(GetBitContext *s,
+ UINT8 *buffer, int buffer_size);
+
int check_marker(GetBitContext *s, char *msg);
void align_get_bits(GetBitContext *s);
int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
@@ -666,126 +718,43 @@ int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
const void *codes, int codes_wrap, int codes_size);
void free_vlc(VLC *vlc);
-#ifdef ALT_BITSTREAM_READER
-#ifdef ALIGNED_BITSTREAM
-#ifdef ARCH_X86
-#define SHOW_BITS(s, val, n) \
- val= be2me_32( ((uint32_t *)(s)->buffer)[bit_cnt>>5] );\
- {uint32_t result2= be2me_32( ((uint32_t *)(s)->buffer)[(bit_cnt>>5) + 1] );\
- asm ("shldl %%cl, %2, %0\n\t"\
- : "=r" (val)\
- : "0" (val), "r" (result2), "c" (bit_cnt));\
- ((uint32_t)val)>>= 32 - n;}
-#else //ARCH_X86
-#define SHOW_BITS(s, val, n) \
- val= be2me_32( ((uint32_t *)(s)->buffer)[bit_cnt>>5] );\
- {uint32_t result2= be2me_32( ((uint32_t *)(s)->buffer)[(bit_cnt>>5) + 1] );\
- val<<= (bit_cnt&0x1F);\
- result2= (result2>>1) >> (31-(bit_cnt&0x1F));\
- val|= result2;\
- ((uint32_t)val)>>= 32 - n;}
-#endif //!ARCH_X86
-#else //ALIGNED_BITSTREAM
-#define SHOW_BITS(s, val, n) \
- val= be2me_32( unaligned32( ((uint8_t *)(s)->buffer)+(bit_cnt>>3) ) );\
- val<<= (bit_cnt&0x07);\
- ((uint32_t)val)>>= 32 - n;
-#endif // !ALIGNED_BITSTREAM
-#define FLUSH_BITS(n) bit_cnt+=n;
-#define SAVE_BITS(s) bit_cnt= (s)->index;
-#define RESTORE_BITS(s) (s)->index= bit_cnt;
-#else
-
-/* macro to go faster */
-/* n must be <= 24 */
-/* XXX: optimize buffer end test */
-#define SHOW_BITS(s, val, n)\
-{\
- if (bit_cnt < n && buf_ptr < (s)->buf_end) {\
- bit_buf |= *buf_ptr++ << (24 - bit_cnt);\
- bit_cnt += 8;\
- if (bit_cnt < n && buf_ptr < (s)->buf_end) {\
- bit_buf |= *buf_ptr++ << (24 - bit_cnt);\
- bit_cnt += 8;\
- if (bit_cnt < n && buf_ptr < (s)->buf_end) {\
- bit_buf |= *buf_ptr++ << (24 - bit_cnt);\
- bit_cnt += 8;\
- }\
- }\
- }\
- val = bit_buf >> (32 - n);\
-}
-
-/* SHOW_BITS with n1 >= n must be been done before */
-#define FLUSH_BITS(n)\
-{\
- bit_buf <<= n;\
- bit_cnt -= n;\
-}
-
-#define SAVE_BITS(s) \
-{\
- bit_cnt = (s)->bit_cnt;\
- bit_buf = (s)->bit_buf;\
- buf_ptr = (s)->buf_ptr;\
-}
-
-#define RESTORE_BITS(s) \
-{\
- (s)->buf_ptr = buf_ptr;\
- (s)->bit_buf = bit_buf;\
- (s)->bit_cnt = bit_cnt;\
-}
-#endif // !ALT_BITSTREAM_READER
-
static inline int get_vlc(GetBitContext *s, VLC *vlc)
{
int code, n, nb_bits, index;
- INT16 *table_codes;
- INT8 *table_bits;
- int bit_cnt;
-#ifndef ALT_BITSTREAM_READER
- UINT32 bit_buf;
- UINT8 *buf_ptr;
-#endif
+ VLC_TYPE (*table)[2];
+ OPEN_READER(re, s)
+
+ UPDATE_CACHE(re, s)
- SAVE_BITS(s);
nb_bits = vlc->bits;
- table_codes = vlc->table_codes;
- table_bits = vlc->table_bits;
+ table = vlc->table;
#ifdef FAST_GET_FIRST_VLC
- SHOW_BITS(s, index, nb_bits);
- code = table_codes[index];
- n = table_bits[index];
+ index= SHOW_UBITS(re, s, nb_bits);
+ code = table[index][0];
+ n = table[index][1];
if (n > 0) {
/* most common case (90%)*/
- FLUSH_BITS(n);
-#ifdef DUMP_STREAM
- {
- int n= bit_cnt - s->index;
- skip_bits(s, n);
- RESTORE_BITS(s);
- }
-#endif
- RESTORE_BITS(s);
+ LAST_SKIP_BITS(re, s, n)
+ CLOSE_READER(re, s)
return code;
} else if (n == 0) {
return -1;
} else {
- FLUSH_BITS(nb_bits);
+ LAST_SKIP_BITS(re, s, nb_bits)
+ UPDATE_CACHE(re, s) //this isnt needed but its faster if its here
+
nb_bits = -n;
- table_codes = vlc->table_codes + code;
- table_bits = vlc->table_bits + code;
+ table = vlc->table + code;
}
#endif
for(;;) {
- SHOW_BITS(s, index, nb_bits);
- code = table_codes[index];
- n = table_bits[index];
+ index= SHOW_UBITS(re, s, nb_bits);
+ code = table[index][0];
+ n = table[index][1];
if (n > 0) {
/* most common case */
- FLUSH_BITS(n);
+ SKIP_BITS(re, s, n)
#ifdef STATS
st_bit_counts[st_current_index] += n;
#endif
@@ -793,23 +762,16 @@ static inline int get_vlc(GetBitContext *s, VLC *vlc)
} else if (n == 0) {
return -1;
} else {
- FLUSH_BITS(nb_bits);
+ LAST_SKIP_BITS(re, s, nb_bits)
+ UPDATE_CACHE(re, s)
#ifdef STATS
st_bit_counts[st_current_index] += nb_bits;
#endif
nb_bits = -n;
- table_codes = vlc->table_codes + code;
- table_bits = vlc->table_bits + code;
+ table = vlc->table + code;
}
}
-#ifdef DUMP_STREAM
- {
- int n= bit_cnt - s->index;
- skip_bits(s, n);
- RESTORE_BITS(s);
- }
-#endif
- RESTORE_BITS(s);
+ CLOSE_READER(re, s)
return code;
}
diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index 9b917ce..53c4e32 100644
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -961,21 +961,20 @@ static int mpeg1_decode_block(MpegEncContext *s,
dprintf("dc=%d diff=%d\n", dc, diff);
i = 1;
} else {
- int bit_cnt, v;
- UINT32 bit_buf;
- UINT8 *buf_ptr;
+ int v;
+ OPEN_READER(re, &s->gb);
i = 0;
/* special case for the first coef. no need to add a second vlc table */
- SAVE_BITS(&s->gb);
- SHOW_BITS(&s->gb, v, 2);
+ UPDATE_CACHE(re, &s->gb);
+ v= SHOW_UBITS(re, &s->gb, 2);
if (v & 2) {
run = 0;
level = 1 - ((v & 1) << 1);
- FLUSH_BITS(2);
- RESTORE_BITS(&s->gb);
+ SKIP_BITS(re, &s->gb, 2);
+ CLOSE_READER(re, &s->gb);
goto add_coef;
}
- RESTORE_BITS(&s->gb);
+ CLOSE_READER(re, &s->gb);
}
/* now quantify & encode AC coefs */
@@ -1035,26 +1034,25 @@ static int mpeg2_decode_block_non_intra(MpegEncContext *s,
mismatch = 1;
{
- int bit_cnt, v;
- UINT32 bit_buf;
- UINT8 *buf_ptr;
+ int v;
+ OPEN_READER(re, &s->gb);
i = 0;
- if (n < 4)
+ if (n < 4)
matrix = s->inter_matrix;
else
matrix = s->chroma_inter_matrix;
-
+
/* special case for the first coef. no need to add a second vlc table */
- SAVE_BITS(&s->gb);
- SHOW_BITS(&s->gb, v, 2);
+ UPDATE_CACHE(re, &s->gb);
+ v= SHOW_UBITS(re, &s->gb, 2);
if (v & 2) {
run = 0;
level = 1 - ((v & 1) << 1);
- FLUSH_BITS(2);
- RESTORE_BITS(&s->gb);
+ SKIP_BITS(re, &s->gb, 2);
+ CLOSE_READER(re, &s->gb);
goto add_coef;
}
- RESTORE_BITS(&s->gb);
+ CLOSE_READER(re, &s->gb);
}
/* now quantify & encode AC coefs */
diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c
index 21ce140..1dabdac 100644
--- a/libavcodec/mpegaudiodec.c
+++ b/libavcodec/mpegaudiodec.c
@@ -1457,11 +1457,8 @@ static void seek_to_maindata(MPADecodeContext *s, long backstep)
UINT8 *ptr;
/* compute current position in stream */
-#ifdef ALT_BITSTREAM_READER
- ptr = s->gb.buffer + (s->gb.index>>3);
-#else
- ptr = s->gb.buf_ptr - (s->gb.bit_cnt >> 3);
-#endif
+ ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3);
+
/* copy old data before current one */
ptr -= backstep;
memcpy(ptr, s->inbuf1[s->inbuf_index ^ 1] +
@@ -1547,9 +1544,7 @@ static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
{
int s_index;
int linbits, code, x, y, l, v, i, j, k, pos;
- UINT8 *last_buf_ptr;
- UINT32 last_bit_buf;
- int last_bit_cnt;
+ GetBitContext last_gb;
VLC *vlc;
UINT8 *code_table;
@@ -1608,36 +1603,20 @@ static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
/* high frequencies */
vlc = &huff_quad_vlc[g->count1table_select];
- last_buf_ptr = NULL;
- last_bit_buf = 0;
- last_bit_cnt = 0;
+ last_gb.buffer = NULL;
while (s_index <= 572) {
pos = get_bits_count(&s->gb);
if (pos >= end_pos) {
- if (pos > end_pos && last_buf_ptr != NULL) {
+ if (pos > end_pos && last_gb.buffer != NULL) {
/* some encoders generate an incorrect size for this
part. We must go back into the data */
s_index -= 4;
-#ifdef ALT_BITSTREAM_READER
- s->gb.buffer = last_buf_ptr;
- s->gb.index = last_bit_cnt;
-#else
- s->gb.buf_ptr = last_buf_ptr;
- s->gb.bit_buf = last_bit_buf;
- s->gb.bit_cnt = last_bit_cnt;
-#endif
+ s->gb = last_gb;
}
break;
}
-#ifdef ALT_BITSTREAM_READER
- last_buf_ptr = s->gb.buffer;
- last_bit_cnt = s->gb.index;
-#else
- last_buf_ptr = s->gb.buf_ptr;
- last_bit_buf = s->gb.bit_buf;
- last_bit_cnt = s->gb.bit_cnt;
-#endif
-
+ last_gb= s->gb;
+
code = get_vlc(&s->gb, vlc);
dprintf("t=%d code=%d\n", g->count1table_select, code);
if (code < 0)
--
Libav/FFmpeg packaging
More information about the pkg-multimedia-commits
mailing list