int hitbuffer_inc(hitbuffer *hb, Z32 *hit) {
hb->freq += 1LLU; //LLU for 64-bit. OSX 10.5 is VERY finicky about this.
int result;
if (hb->freq < PHILO_INDEX_CUTOFF) {
add_to_dir(hb, hit, 1);
// fprintf(stderr, "added hit for %s...\n", hb->word);
}
else if (hb->freq == PHILO_INDEX_CUTOFF) {
//when the frequency reaches 10, we start using a block-header layout.
//each "hit" in the directory corresponds to a large, compressed block of hits.
//by comparing the directory headers to the query, the search engine skips blocks if possible.
result = add_to_block(hb,&(hb->dir[1*hb->db->dbspec->fields]),PHILO_INDEX_CUTOFF - 2);
if (result == PHILO_BLOCK_FULL) {
fprintf(stderr, "you can't fit PHILO_INDEX_CUTOFF hits into a block! adjust your block size, or your index cutoff.\n");
}
hb->dir_length = 1LLU;
hb->type = 1;
result = add_to_block(hb,hit,1);
// fprintf(stderr, "clearing dir. started new block for %s...\n", hb->word);
}
if (hb->freq > PHILO_INDEX_CUTOFF) {
result = add_to_block(hb,hit,1);
if (result == PHILO_BLOCK_FULL) {
// IF the block add failed,
write_blk(hb); //write the full block out, start a new one,
add_to_dir(hb,hit,1); //then push the current hit onto the directory.
// fprintf(stderr, "started new block for %s...\n", hb->word);
}
}
return 0;
}
/******************************************************************************
** huffman_encode
** --------------------------------------------------------------------------
** Quantize and Encode a 8x8 DCT block by JPEG Huffman lossless coding.
** This function writes encoded bit-stream into bit-buffer.
**
** ARGUMENTS:
** ctx - pointer to encoder context;
** data - pointer to 8x8 DCT block;
**
** RETURN: -
******************************************************************************/
void huffman_encode(huffman_t *const ctx, const short data[], unsigned block_num)
{
unsigned magn, bits;
unsigned zerorun, i;
short diff;
short dc = quantize(data[0], ctx->qtable[0]);
// WARNING: in order to everything to work correctly
// the get_DC_value must be called before the block_start
// otherwise it returns a wrong DC value in case of megablocks
// (the block_start reset the force_marker variable, which is
// used by get_DC_value
diff = get_DC_value(dc, block_num);
block_start(block_num);
bits = huffman_bits(diff);
magn = huffman_magnitude(diff);
add_to_block(ctx->hdcbit[magn], ctx->hdclen[magn]);
add_to_block(bits, magn);
for (zerorun = 0, i = 1; i < 64; i++)
{
const short ac = quantize(data[zig[i]], ctx->qtable[zig[i]]);
if (ac) {
while (zerorun >= 16) {
zerorun -= 16;
// ZRL
add_to_block(ctx->hacbit[15][0], ctx->haclen[15][0]);
}
bits = huffman_bits(ac);
magn = huffman_magnitude(ac);
add_to_block(ctx->hacbit[zerorun][magn], ctx->haclen[zerorun][magn]);
add_to_block(bits, magn);
zerorun = 0;
}
else zerorun++;
}
if (zerorun) { // EOB - End Of Block
add_to_block(ctx->hacbit[0][0], ctx->haclen[0][0]);
}
block_end(&bitbuf);
}
