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optimizing mpeg1_decode_block()

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Originally committed as revision 985 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Michael Niedermayer 23 years ago
parent 8e1652dc9d
commit a02017367b
2 changed files with 175 additions and 78 deletions
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  1. 173
      libavcodec/mpeg12.c
  2. 16
      libavcodec/mpegvideo.c

173
libavcodec/mpeg12.c
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@ -52,7 +52,10 @@ static void mpeg1_encode_block(MpegEncContext *s,
int component);
static void mpeg1_encode_motion(MpegEncContext *s, int val);
static void mpeg1_skip_picture(MpegEncContext *s, int pict_num);
static int mpeg1_decode_block(MpegEncContext *s,
static inline int mpeg1_decode_block_inter(MpegEncContext *s,
DCTELEM *block,
int n);
static inline int mpeg1_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n);
static int mpeg2_decode_block_non_intra(MpegEncContext *s,
@ -92,8 +95,8 @@ static void init_2d_vlc_rl(RLTable *rl)
run= 65;
level= 0;
}else if(code==rl->n+1){ //eob
run= 192;
level= 1;
run= 0;
level= 127;
}else{
run= rl->table_run [code] + 1;
level= rl->table_level[code];
@ -932,31 +935,36 @@ static int mpeg_decode_mb(MpegEncContext *s,
if (s->mpeg2) {
if (s->mb_intra) {
for(i=0;i<6;i++) {
if (cbp & (1 << (5 - i))) {
if (mpeg2_decode_block_intra(s, block[i], i) < 0)
return -1;
} else {
s->block_last_index[i] = -1;
}
}
} else {
for(i=0;i<6;i++) {
if (cbp & (1 << (5 - i))) {
if (cbp & 32) {
if (mpeg2_decode_block_non_intra(s, block[i], i) < 0)
return -1;
} else {
s->block_last_index[i] = -1;
}
cbp+=cbp;
}
}
} else {
if (s->mb_intra) {
for(i=0;i<6;i++) {
if (cbp & (1 << (5 - i))) {
if (mpeg1_decode_block(s, block[i], i) < 0)
if (mpeg1_decode_block_intra(s, block[i], i) < 0)
return -1;
}
}else{
for(i=0;i<6;i++) {
if (cbp & 32) {
if (mpeg1_decode_block_inter(s, block[i], i) < 0)
return -1;
} else {
s->block_last_index[i] = -1;
}
cbp+=cbp;
}
}
}
return 0;
@ -1018,16 +1026,17 @@ static inline int decode_dc(MpegEncContext *s, int component)
return diff;
}
static int mpeg1_decode_block(MpegEncContext *s,
static inline int mpeg1_decode_block_intra(MpegEncContext *s,
DCTELEM *block,
int n)
{
int level, dc, diff, i, j, run;
int code, component;
int component;
RLTable *rl = &rl_mpeg1;
UINT8 * const scantable= s->intra_scantable.permutated;
const UINT16 *quant_matrix= s->intra_matrix;
const int qscale= s->qscale;
if (s->mb_intra) {
/* DC coef */
component = (n <= 3 ? 0 : n - 4 + 1);
diff = decode_dc(s, component);
@ -1036,60 +1045,136 @@ static int mpeg1_decode_block(MpegEncContext *s,
dc = s->last_dc[component];
dc += diff;
s->last_dc[component] = dc;
block[0] = dc;
block[0] = dc<<3;
dprintf("dc=%d diff=%d\n", dc, diff);
i = 1;
i = 0;
{
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])>>3;
level= (level-1)|1;
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, 8); SKIP_BITS(re, &s->gb, 8);
if (level == -128) {
level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
} else if (level == 0) {
level = SHOW_UBITS(re, &s->gb, 8) ; LAST_SKIP_BITS(re, &s->gb, 8);
}
i += run;
j = scantable[i];
if(level<0){
level= -level;
level= (level*qscale*quant_matrix[j])>>3;
level= (level-1)|1;
level= -level;
}else{
level= (level*qscale*quant_matrix[j])>>3;
level= (level-1)|1;
}
}
if (i > 63){
fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
block[j] = level;
}
CLOSE_READER(re, &s->gb);
}
s->block_last_index[n] = i;
return 0;
}
static inline int mpeg1_decode_block_inter(MpegEncContext *s,
DCTELEM *block,
int n)
{
int level, i, j, run;
RLTable *rl = &rl_mpeg1;
UINT8 * const scantable= s->intra_scantable.permutated;
const UINT16 *quant_matrix= s->inter_matrix;
const int qscale= s->qscale;
{
int v;
OPEN_READER(re, &s->gb);
i = 0;
i = -1;
/* 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 = 1 - ((v & 1) << 1);
SKIP_BITS(re, &s->gb, 2);
CLOSE_READER(re, &s->gb);
goto add_coef;
level= (3*qscale*quant_matrix[0])>>4;
level= (level-1)|1;
if(v&1)
level= -level;
block[ scantable[0] ] = level;
i++;
}
CLOSE_READER(re, &s->gb);
}
{
OPEN_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) {
return -1;
}
if (code == 112) {
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 (code == 111) {
} else if(level != 0) {
i += run;
j = scantable[i];
level= ((level*2+1)*qscale*quant_matrix[j])>>4;
level= (level-1)|1;
level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
LAST_SKIP_BITS(re, &s->gb, 1);
} else {
/* escape */
run = get_bits(&s->gb, 6);
level = get_bits(&s->gb, 8);
level= (level + ((-1)<<7)) ^ ((-1)<<7); //sign extension
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, 8); SKIP_BITS(re, &s->gb, 8);
if (level == -128) {
level = get_bits(&s->gb, 8) - 256;
level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
} else if (level == 0) {
level = get_bits(&s->gb, 8);
}
} else {
run = rl->table_run[code];
level = rl->table_level[code];
if (get_bits1(&s->gb))
level = -level;
level = SHOW_UBITS(re, &s->gb, 8) ; LAST_SKIP_BITS(re, &s->gb, 8);
}
i += run;
if (i >= 64)
return -1;
add_coef:
dprintf("%d: run=%d level=%d\n", n, run, level);
j = scantable[i];
if(level<0){
level= -level;
level= ((level*2+1)*qscale*quant_matrix[j])>>4;
level= (level-1)|1;
level= -level;
}else{
level= ((level*2+1)*qscale*quant_matrix[j])>>4;
level= (level-1)|1;
}
}
if (i > 63){
fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
return -1;
}
block[j] = level;
i++;
}
s->block_last_index[n] = i-1;
CLOSE_READER(re, &s->gb);
}
s->block_last_index[n] = i;
return 0;
}

16
libavcodec/mpegvideo.c
Unescape View File

@ -1517,7 +1517,6 @@ static inline void MPV_motion(MpegEncContext *s,
static inline void put_dct(MpegEncContext *s,
DCTELEM *block, int i, UINT8 *dest, int line_size)
{
if (!s->mpeg2)
s->dct_unquantize(s, block, i, s->qscale);
s->idct_put (dest, line_size, block);
}
@ -1723,7 +1722,8 @@ void MPV_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
if(s->hurry_up>1) goto the_end;
/* add dct residue */
if(s->encoding || !(s->mpeg2 || s->h263_msmpeg4 || (s->codec_id==CODEC_ID_MPEG4 && !s->mpeg_quant))){
if(s->encoding || !( s->mpeg2 || s->h263_msmpeg4 || s->codec_id==CODEC_ID_MPEG1VIDEO
|| (s->codec_id==CODEC_ID_MPEG4 && !s->mpeg_quant))){
add_dequant_dct(s, block[0], 0, dest_y, dct_linesize);
add_dequant_dct(s, block[1], 1, dest_y + 8, dct_linesize);
add_dequant_dct(s, block[2], 2, dest_y + dct_offset, dct_linesize);
@ -1746,6 +1746,7 @@ void MPV_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
}
} else {
/* dct only in intra block */
if(s->encoding || !(s->mpeg2 || s->codec_id==CODEC_ID_MPEG1VIDEO)){
put_dct(s, block[0], 0, dest_y, dct_linesize);
put_dct(s, block[1], 1, dest_y + 8, dct_linesize);
put_dct(s, block[2], 2, dest_y + dct_offset, dct_linesize);
@ -1755,6 +1756,17 @@ void MPV_decode_mb(MpegEncContext *s, DCTELEM block[6][64])
put_dct(s, block[4], 4, dest_cb, s->uvlinesize);
put_dct(s, block[5], 5, dest_cr, s->uvlinesize);
}
}else{
s->idct_put(dest_y , dct_linesize, block[0]);
s->idct_put(dest_y + 8, dct_linesize, block[1]);
s->idct_put(dest_y + dct_offset , dct_linesize, block[2]);
s->idct_put(dest_y + dct_offset + 8, dct_linesize, block[3]);
if(!(s->flags&CODEC_FLAG_GRAY)){
s->idct_put(dest_cb, s->uvlinesize, block[4]);
s->idct_put(dest_cr, s->uvlinesize, block[5]);
}
}
}
}
the_end:

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