VP8: slightly faster DCT coefficient probability update

Originally committed as revision 24687 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Jason Garrett-Glaser 2010-08-03 23:21:47 +00:00
parent 2eef529195
commit b0d5879513
2 changed files with 16 additions and 3 deletions

View File

@ -494,9 +494,8 @@ static int decode_frame_header(VP8Context *s, const uint8_t *buf, int buf_size)
for (l = 0; l < NUM_DCT_TOKENS-1; l++)
if (vp56_rac_get_prob_branchy(c, vp8_token_update_probs[i][j][k][l])) {
int prob = vp8_rac_get_uint(c, 8);
for (m = 0; m < 16; m++)
if (vp8_coeff_band[m] == j)
s->prob->token[i][m][k][l] = prob;
for (m = 0; vp8_coeff_band_indexes[j][m] >= 0; m++)
s->prob->token[i][vp8_coeff_band_indexes[j][m]][k][l] = prob;
}
if ((s->mbskip_enabled = vp8_rac_get(c)))

View File

@ -293,6 +293,20 @@ static const uint8_t vp8_coeff_band[16] =
0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7
};
/* Inverse of vp8_coeff_band: mappings of bands to coefficient indexes.
* Each list is -1-terminated. */
static const int8_t vp8_coeff_band_indexes[8][10] =
{
{0, -1},
{1, -1},
{2, -1},
{3, -1},
{5, -1},
{6, -1},
{4, 7, 8, 9, 10, 11, 12, 13, 14, -1},
{15, -1}
};
static const uint8_t vp8_dct_cat1_prob[] = { 159, 0 };
static const uint8_t vp8_dct_cat2_prob[] = { 165, 145, 0 };
static const uint8_t vp8_dct_cat3_prob[] = { 173, 148, 140, 0 };