/*
* Common bit i/o utils
- * Copyright (c) 2000, 2001 Gerard Lantau.
+ * Copyright (c) 2000, 2001 Fabrice Bellard.
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * This library 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 of the License, or (at your option) any later version.
*
- * This program is distributed in the hope that it will be useful,
+ * This library 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 General Public License for more details.
+ * 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 General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
*/
-#include "common.h"
-#include <math.h>
+#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
+};
void init_put_bits(PutBitContext *s,
- UINT8 *buffer, int buffer_size,
+ uint8_t *buffer, int buffer_size,
void *opaque,
- void (*write_data)(void *, UINT8 *, int))
+ void (*write_data)(void *, uint8_t *, int))
{
s->buf = buffer;
s->buf_end = s->buf + buffer_size;
}
/* return the number of bits output */
-INT64 get_bit_count(PutBitContext *s)
+int64_t get_bit_count(PutBitContext *s)
{
#ifdef ALT_BITSTREAM_WRITER
return s->data_out_size * 8 + s->index;
#else
- return (s->buf_ptr - s->buf + s->data_out_size) * 8 + 32 - (INT64)s->bit_left;
+ return (s->buf_ptr - s->buf + s->data_out_size) * 8 + 32 - (int64_t)s->bit_left;
#endif
}
#endif
}
-/* pad the end of the output stream with zeros */
-#ifndef ALT_BITSTREAM_WRITER
-void jflush_put_bits(PutBitContext *s)
+void put_string(PutBitContext * pbc, char *s)
{
- unsigned int b;
- s->bit_buf<<= s->bit_left;
- s->bit_buf |= ~1U >> (32 - s->bit_left); /* set all the unused bits to one */
-
- while (s->bit_left < 32) {
- b = s->bit_buf >> 24;
- *s->buf_ptr++ = b;
- if (b == 0xff)
- *s->buf_ptr++ = 0;
- s->bit_buf<<=8;
- s->bit_left+=8;
+ while(*s){
+ put_bits(pbc, 8, *s);
+ s++;
}
- s->bit_left=32;
- s->bit_buf=0;
-}
-#else
-void jflush_put_bits(PutBitContext *s)
-{
- int num= ( - s->index) & 7;
- jput_bits(s, num,0xFF>>(8-num));
+ put_bits(pbc, 8, 0);
}
-#endif
/* bit input functions */
-void init_get_bits(GetBitContext *s,
- UINT8 *buffer, int buffer_size)
+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;
- 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;
- }
+#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
- 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;
-#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) {
-#if 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++;
- }
- s->buf_ptr = buf_ptr;
- val |= bit_buf >> (32 + bit_cnt);
- bit_buf <<= - bit_cnt;
- bit_cnt += 32;
+ 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)
+int check_marker(GetBitContext *s, const char *msg)
{
int bit= get_bits1(s);
if(!bit) printf("Marker bit missing %s\n", 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
#define GET_DATA(v, table, i, wrap, size) \
{\
- UINT8 *ptr = (UINT8 *)table + i * wrap;\
+ const uint8_t *ptr = (const uint8_t *)table + i * wrap;\
switch(size) {\
case 1:\
- v = *(UINT8 *)ptr;\
+ v = *(const uint8_t *)ptr;\
break;\
case 2:\
- v = *(UINT16 *)ptr;\
+ v = *(const uint16_t *)ptr;\
break;\
default:\
- v = *(UINT32 *)ptr;\
+ v = *(const uint32_t *)ptr;\
break;\
}\
}
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 = av_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,
- UINT32 code_prefix, int n_prefix)
+ uint32_t code_prefix, int n_prefix)
{
int i, j, k, n, table_size, table_index, nb, n1, index;
- UINT32 code;
- INT8 *table_bits;
- INT16 *table_codes;
+ uint32_t code;
+ 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 */
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 {
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,
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;
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
bits, bits_wrap, bits_size,
codes, codes_wrap, codes_size,
0, 0) < 0) {
- if (vlc->table_bits)
- free(vlc->table_bits);
- if (vlc->table_codes)
- free(vlc->table_codes);
+ av_free(vlc->table);
return -1;
}
return 0;
void free_vlc(VLC *vlc)
{
- free(vlc->table_bits);
- free(vlc->table_codes);
+ av_free(vlc->table);
+}
+
+int ff_gcd(int a, int b){
+ if(b) return ff_gcd(b, a%b);
+ else return a;
}
+void ff_float2fraction(int *nom_arg, int *denom_arg, double f, int max){
+ double best_diff=1E10, diff;
+ int best_denom=1, best_nom=1;
+ int nom, denom, gcd;
+
+ //brute force here, perhaps we should try continued fractions if we need large max ...
+ for(denom=1; denom<=max; denom++){
+ nom= (int)(f*denom + 0.5);
+ if(nom<=0 || nom>max) continue;
+
+ diff= ABS( f - (double)nom / (double)denom );
+ if(diff < best_diff){
+ best_diff= diff;
+ best_nom= nom;
+ best_denom= denom;
+ }
+ }
+
+ gcd= ff_gcd(best_nom, best_denom);
+ best_nom /= gcd;
+ best_denom /= gcd;
+
+ *nom_arg= best_nom;
+ *denom_arg= best_denom;
+}
projects / ffmpeg / blobdiff