static int huff_build(VLC *vlc, uint8_t *len)
{
HuffEntry he[256];
uint32_t codes[256];
uint8_t bits[256];
uint8_t syms[256];
uint32_t code;
int i;
for (i = 0; i < 256; i++) {
he[i].sym = 255 - i;
he[i].len = len[i];
}
AV_QSORT(he, 256, HuffEntry, huff_cmp_len);
code = 1;
for (i = 255; i >= 0; i--) {
codes[i] = code >> (32 - he[i].len);
bits[i] = he[i].len;
syms[i] = he[i].sym;
code += 0x80000000u >> (he[i].len - 1);
}
ff_free_vlc(vlc);
return ff_init_vlc_sparse(vlc, FFMIN(he[255].len, 12), 256,
bits, sizeof(*bits), sizeof(*bits),
codes, sizeof(*codes), sizeof(*codes),
syms, sizeof(*syms), sizeof(*syms), 0);
}
static int huff_build10(VLC *vlc, uint8_t *len)
{
HuffEntry he[1024];
uint32_t codes[1024];
uint8_t bits[1024];
uint16_t syms[1024];
uint32_t code;
int i;
for (i = 0; i < 1024; i++) {
he[i].sym = 1023 - i;
he[i].len = len[i];
}
AV_QSORT(he, 1024, HuffEntry, huff_cmp_len10);
code = 1;
for (i = 1023; i >= 0; i--) {
codes[i] = code >> (32 - he[i].len);
bits[i] = he[i].len;
syms[i] = he[i].sym;
code += 0x80000000u >> (he[i].len - 1);
}
ff_free_vlc(vlc);
return ff_init_vlc_sparse(vlc, FFMIN(he[1023].len, 12), 1024,
bits, sizeof(*bits), sizeof(*bits),
codes, sizeof(*codes), sizeof(*codes),
syms, sizeof(*syms), sizeof(*syms), 0);
}
static int huff_build12(VLC *vlc, uint8_t *len)
{
HuffEntry he[4096];
uint32_t codes[4096];
uint8_t bits[4096];
uint16_t syms[4096];
uint32_t code;
int i;
for (i = 0; i < 4096; i++) {
he[i].sym = 4095 - i;
he[i].len = len[i];
if (len[i] == 0 || len[i] > 32)
return AVERROR_INVALIDDATA;
}
AV_QSORT(he, 4096, HuffEntry, huff_cmp_len12);
code = 1;
for (i = 4095; i >= 0; i--) {
codes[i] = code >> (32 - he[i].len);
bits[i] = he[i].len;
syms[i] = he[i].sym;
code += 0x80000000u >> (he[i].len - 1);
}
ff_free_vlc(vlc);
return ff_init_vlc_sparse(vlc, FFMIN(he[4095].len, 14), 4096,
bits, sizeof(*bits), sizeof(*bits),
codes, sizeof(*codes), sizeof(*codes),
syms, sizeof(*syms), sizeof(*syms), 0);
}