#include "wma.h"
#include "bitstream.h"
+/** Read an 8, 16, or 32 bit entity from a VLC table. */
#define GET_DATA(v, table, i, size) \
{\
const uint8_t *ptr = (const uint8_t *)table + i * size; \
const void *bits, const void *codes, int codes_size,
uint32_t code_prefix, int n_prefix)
{
- int i, j, k, n, table_size, table_index, nb, n1, idx, code_prefix2,
- symbol;
+ int i, j, k, n, table_size, table_index, nb, n1, idx, code_prefix2;
uint32_t code;
VLC_TYPE(*table)[2];
table = &vlc->table[table_index];
for (i = 0; i < table_size; i++) {
- table[i][1] = 0; //bits
- table[i][0] = -1; //codes
+ table[i][1] = 0; /* bits */
+ table[i][0] = -1; /* codes */
}
- /* map codes and compute auxillary table sizes */
+ /* map codes and compute auxiliary table sizes */
for (i = 0; i < nb_codes; i++) {
GET_DATA(n, bits, i, 1);
GET_DATA(code, codes, i, codes_size);
/* we accept tables with holes */
if (n <= 0)
continue;
- symbol = i;
/* if code matches the prefix, it is in the table */
n -= n_prefix;
code_prefix2 = code >> n;
PARA_EMERG_LOG("incorrect code\n");
exit(EXIT_FAILURE);
}
- table[j][1] = n; //bits
- table[j][0] = symbol;
+ table[j][1] = n; /* bits */
+ table[j][0] = i;
j++;
}
} else {
n -= table_nb_bits;
j = (code >> n) & ((1 << table_nb_bits) - 1);
/* compute table size */
- n1 = -table[j][1]; //bits
+ n1 = -table[j][1]; /* bits */
if (n > n1)
n1 = n;
- table[j][1] = -n1; //bits
+ table[j][1] = -n1; /* bits */
}
}
- /* fill auxillary tables recursively */
+ /* fill auxiliary tables recursively */
for (i = 0; i < table_size; i++) {
- n = table[i][1]; //bits
+ n = table[i][1]; /* bits */
if (n < 0) {
n = -n;
if (n > table_nb_bits) {
n = table_nb_bits;
- table[i][1] = -n; //bits
+ table[i][1] = -n; /* bits */
}
idx = build_table(vlc, n, nb_codes, bits, codes,
codes_size, (code_prefix << table_nb_bits) | i,
n_prefix + table_nb_bits);
/* vlc->table might have changed */
table = &vlc->table[table_index];
- table[i][0] = idx; //code
+ table[i][0] = idx; /* code */
}
}
return table_index;
build_table(vlc, nb_bits, nb_codes, bits, codes, codes_size, 0, 0);
}
+/**
+ * Deallocate all resources of a VLC table.
+ *
+ * \param vlc Pointer to an initialized vlc structure.
+ *
+ * The table given by \a vlc must have been initialized earlier via \ref
+ * init_vlc().
+ */
void free_vlc(struct vlc *vlc)
{
freep(&vlc->table);