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Enable coefficient scaling

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Originally committed as revision 5651 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Kostya Shishkov 2006-07-07 04:51:50 +00:00
parent 928dc49d0e
commit 50af2fd30d
1 changed files with 21 additions and 22 deletions
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43
libavcodec/vc1.c
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@ -1731,7 +1731,7 @@ static inline int vc1_pred_dc(MpegEncContext *s, int overlap, int pq, int n,
int a, b, c, wrap, pred, scale;
int16_t *dc_val;
int mb_pos = s->mb_x + s->mb_y * s->mb_stride;
int mb_pos2, q1, q2;
int q1, q2 = 0;
/* find prediction - wmv3_dc_scale always used here in fact */
if (n < 4) scale = s->y_dc_scale;
@ -1751,28 +1751,32 @@ static inline int vc1_pred_dc(MpegEncContext *s, int overlap, int pq, int n,
if(abs(a - b) <= abs(b - c)) {
pred = c;
*dir_ptr = 1;//left
q2 = s->current_picture.qscale_table[mb_pos - 1];
} else {
pred = a;
*dir_ptr = 0;//top
q2 = s->current_picture.qscale_table[mb_pos - s->mb_stride];
}
} else if(a_avail) {
pred = a;
*dir_ptr = 0;//top
q2 = s->current_picture.qscale_table[mb_pos - s->mb_stride];
} else if(c_avail) {
pred = c;
*dir_ptr = 1;//left
q2 = s->current_picture.qscale_table[mb_pos - 1];
} else {
pred = 0;
*dir_ptr = 1;//left
}
/* scale coeffs if needed
mb_pos2 = mb_pos - *dir_ptr - (1 - *dir_ptr) * s->mb_stride;
q1 = s->y_dc_scale_table[s->current_picture.qscale_table[mb_pos]];
q2 = s->y_dc_scale_table[s->current_picture.qscale_table[mb_pos2]];
if(q2 && q1!=q2 && ((*dir_ptr && c_avail) || (!*dir_ptr && a_avail))) {
pred = (pred * q2 * vc1_dqscale[q1 - 1] + 0x20000) >> 18;
} */
/* scale coeffs if needed */
q1 = s->current_picture.qscale_table[mb_pos];
if(n && n<4) q2=q1;
if(q2 && q1!=q2) {
pred = (pred * s->y_dc_scale_table[q2] * vc1_dqscale[s->y_dc_scale_table[q1] - 1] + 0x20000) >> 18;
}
/* update predictor */
*dc_val_ptr = &dc_val[0];
@ -2064,6 +2068,7 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
int a_avail = v->a_avail, c_avail = v->c_avail;
int use_pred = s->ac_pred;
int scale;
int q1, q2 = 0;
/* XXX: Guard against dumb values of mquant */
mquant = (mquant < 1) ? 0 : ( (mquant>31) ? 31 : mquant );
@ -2134,6 +2139,11 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
else //top
ac_val -= 16 * s->block_wrap[n];
q1 = s->current_picture.qscale_table[mb_pos];
if(dc_pred_dir && c_avail) q2 = s->current_picture.qscale_table[mb_pos - 1];
if(!dc_pred_dir && a_avail) q2 = s->current_picture.qscale_table[mb_pos - s->mb_stride];
if(n && n<4) q2 = q1;
if(coded) {
int last = 0, skip, value;
const int8_t *zz_table;
@ -2152,13 +2162,7 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
/* apply AC prediction if needed */
if(use_pred) {
/* scale predictors if needed*/
int mb_pos2, q1, q2;
mb_pos2 = mb_pos - dc_pred_dir - (1 - dc_pred_dir) * s->mb_stride;
q1 = s->current_picture.qscale_table[mb_pos];
q2 = s->current_picture.qscale_table[mb_pos2];
if(0 && q2 && q1!=q2 && ((dc_pred_dir && c_avail) || (!dc_pred_dir && a_avail))) {
if(q2 && q1!=q2) {
q1 = q1 * 2 - 1;
q2 = q2 * 2 - 1;
@ -2196,17 +2200,12 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
if(use_pred) i = 63;
} else { // no AC coeffs
int k;
int mb_pos2, q1, q2;
mb_pos2 = mb_pos - dc_pred_dir - (1 - dc_pred_dir) * s->mb_stride;
q1 = s->current_picture.qscale_table[mb_pos];
q2 = s->current_picture.qscale_table[mb_pos2];
memset(ac_val2, 0, 16 * 2);
if(dc_pred_dir) {//left
if(use_pred) {
memcpy(ac_val2, ac_val, 8 * 2);
if(0 && q2 && q1!=q2 && c_avail) {
if(q2 && q1!=q2) {
q1 = q1 * 2 - 1;
q2 = q2 * 2 - 1;
for(k = 1; k < 8; k++)
@ -2216,7 +2215,7 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
} else {//top
if(use_pred) {
memcpy(ac_val2 + 8, ac_val + 8, 8 * 2);
if(0 && q2 && q1!=q2 && a_avail) {
if(q2 && q1!=q2) {
q1 = q1 * 2 - 1;
q2 = q2 * 2 - 1;
for(k = 1; k < 8; k++)