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optimizing mpeg2 decode block stuff

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Originally committed as revision 989 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Michael Niedermayer 23 years ago
parent 144f062500
commit 3729c91296
1 changed files with 116 additions and 113 deletions
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  1. 229
      libavcodec/mpeg12.c

229
libavcodec/mpeg12.c
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@ -58,10 +58,10 @@ static inline int mpeg1_decode_block_inter(MpegEncContext *s,
static inline int mpeg1_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static int mpeg2_decode_block_non_intra(MpegEncContext *s,
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static int mpeg2_decode_block_intra(MpegEncContext *s,
static inline int mpeg2_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
@ -1117,18 +1117,15 @@ static inline int mpeg1_decode_block_inter(MpegEncContext *s,
UPDATE_CACHE(re, &s->gb);
v= SHOW_UBITS(re, &s->gb, 2);
if (v & 2) {
SKIP_BITS(re, &s->gb, 2);
LAST_SKIP_BITS(re, &s->gb, 2);
level= (3*qscale*quant_matrix[0])>>4;
level= (level-1)|1;
if(v&1)
level= -level;
block[ scantable[0] ] = level;
block[0] = level;
i++;
}
CLOSE_READER(re, &s->gb);
}
{
OPEN_READER(re, &s->gb);
/* now quantify & encode AC coefs */
for(;;) {
UPDATE_CACHE(re, &s->gb);
@ -1180,110 +1177,114 @@ static inline int mpeg1_decode_block_inter(MpegEncContext *s,
/* Also does unquantization here, since I will never support mpeg2
encoding */
static int mpeg2_decode_block_non_intra(MpegEncContext *s,
DCTELEM *block,
int n)
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
DCTELEM *block,
int n)
{
int level, i, j, run;
int code;
RLTable *rl = &rl_mpeg1;
const UINT8 *scan_table;
const UINT16 *matrix;
UINT8 * scantable;
const UINT16 *quant_matrix;
const int qscale= s->qscale;
int mismatch;
if (s->alternate_scan)
scan_table = s->intra_v_scantable.permutated;
scantable = s->intra_v_scantable.permutated;
else
scan_table = s->intra_scantable.permutated;
scantable = s->intra_scantable.permutated;
mismatch = 1;
{
int v;
OPEN_READER(re, &s->gb);
i = 0;
i = -1;
if (n < 4)
matrix = s->inter_matrix;
quant_matrix = s->inter_matrix;
else
matrix = s->chroma_inter_matrix;
quant_matrix = s->chroma_inter_matrix;
/* special case for the first coef. no need to add a second vlc table */
UPDATE_CACHE(re, &s->gb);
v= SHOW_UBITS(re, &s->gb, 2);
if (v & 2) {
run = 0;
level = 5 - (v << 1);
SKIP_BITS(re, &s->gb, 2);
CLOSE_READER(re, &s->gb);
goto add_coef;
LAST_SKIP_BITS(re, &s->gb, 2);
level= (3*qscale*quant_matrix[0])>>5;
if(v&1)
level= -level;
block[0] = level;
mismatch ^= level;
i++;
}
CLOSE_READER(re, &s->gb);
}
/* now quantify & encode AC coefs */
for(;;) {
code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2);
if (code < 0){
fprintf(stderr, "invalid ac code at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
if (code == 112) {
break;
} else if (code == 111) {
/* escape */
run = get_bits(&s->gb, 6);
level = get_bits(&s->gb, 12);
level= (level + ((-1)<<11)) ^ ((-1)<<11); //sign extension
} else {
run = rl->table_run[code];
level = rl->table_level[code];
if (get_bits1(&s->gb))
level = -level;
}
i += run;
if (i >= 64){
fprintf(stderr, "run too long at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
add_coef:
j = scan_table[i];
dprintf("%d: run=%d level=%d\n", n, run, level);
/* XXX: optimize */
if (level > 0) {
level = ((level * 2 + 1) * s->qscale * matrix[j]) >> 5;
} else {
level = ((-level * 2 + 1) * s->qscale * matrix[j]) >> 5;
level = -level;
/* now quantify & encode AC coefs */
for(;;) {
UPDATE_CACHE(re, &s->gb);
GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
if(level == 127){
break;
} else if(level != 0) {
i += run;
j = scantable[i];
level= ((level*2+1)*qscale*quant_matrix[j])>>5;
level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
LAST_SKIP_BITS(re, &s->gb, 1);
} else {
/* escape */
run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
UPDATE_CACHE(re, &s->gb);
level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
i += run;
j = scantable[i];
if(level<0){
level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
level= -level;
}else{
level= ((level*2+1)*qscale*quant_matrix[j])>>5;
}
}
if (i > 63){
fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
mismatch ^= level;
block[j] = level;
}
/* XXX: is it really necessary to saturate since the encoder
knows whats going on ? */
mismatch ^= level;
block[j] = level;
i++;
CLOSE_READER(re, &s->gb);
}
block[63] ^= (mismatch & 1);
s->block_last_index[n] = i;
return 0;
}
static int mpeg2_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n)
static inline int mpeg2_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n)
{
int level, dc, diff, i, j, run;
int code, component;
int component;
RLTable *rl;
const UINT8 *scan_table;
const UINT16 *matrix;
UINT8 * scantable;
const UINT16 *quant_matrix;
const int qscale= s->qscale;
int mismatch;
if (s->alternate_scan)
scan_table = s->intra_v_scantable.permutated;
scantable = s->intra_v_scantable.permutated;
else
scan_table = s->intra_scantable.permutated;
scantable = s->intra_scantable.permutated;
/* DC coef */
component = (n <= 3 ? 0 : n - 4 + 1);
if (n < 4){
quant_matrix = s->intra_matrix;
component = 0;
}else{
quant_matrix = s->chroma_intra_matrix;
component = n - 3;
}
diff = decode_dc(s, component);
if (diff >= 0xffff)
return -1;
@ -1293,51 +1294,53 @@ static int mpeg2_decode_block_intra(MpegEncContext *s,
block[0] = dc << (3 - s->intra_dc_precision);
dprintf("dc=%d\n", block[0]);
mismatch = block[0] ^ 1;
i = 1;
i = 0;
if (s->intra_vlc_format)
rl = &rl_mpeg2;
else
rl = &rl_mpeg1;
if (n < 4)
matrix = s->intra_matrix;
else
matrix = s->chroma_intra_matrix;
/* now quantify & encode AC coefs */
for(;;) {
code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2);
if (code < 0){
fprintf(stderr, "invalid ac code at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
if (code == 112) {
break;
} else if (code == 111) {
/* escape */
run = get_bits(&s->gb, 6);
level = get_bits(&s->gb, 12);
level= (level + ((-1)<<11)) ^ ((-1)<<11); //sign extension
} else {
run = rl->table_run[code];
level = rl->table_level[code];
if (get_bits1(&s->gb))
level = -level;
}
i += run;
if (i >= 64){
fprintf(stderr, "run too long at %d %d\n", s->mb_x, s->mb_y);
return -1;
{
OPEN_READER(re, &s->gb);
/* now quantify & encode AC coefs */
for(;;) {
UPDATE_CACHE(re, &s->gb);
GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
if(level == 127){
break;
} else if(level != 0) {
i += run;
j = scantable[i];
level= (level*qscale*quant_matrix[j])>>4;
level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
LAST_SKIP_BITS(re, &s->gb, 1);
} else {
/* escape */
run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
UPDATE_CACHE(re, &s->gb);
level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
i += run;
j = scantable[i];
if(level<0){
level= (-level*qscale*quant_matrix[j])>>4;
level= -level;
}else{
level= (level*qscale*quant_matrix[j])>>4;
}
}
if (i > 63){
fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
mismatch^= level;
block[j] = level;
}
j = scan_table[i];
dprintf("%d: run=%d level=%d\n", n, run, level);
level = (level * s->qscale * matrix[j]) / 16;
/* XXX: is it really necessary to saturate since the encoder
knows whats going on ? */
mismatch ^= level;
block[j] = level;
i++;
CLOSE_READER(re, &s->gb);
}
block[63] ^= (mismatch & 1);
block[63]^= mismatch&1;
s->block_last_index[n] = i;
return 0;
}

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