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FFmpeg/libavcodec/intrax8.c

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/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file intrax8.c
* @brief IntraX8 (J-Frame) subdecoder, used by WMV2 and VC-1
*/
#include "avcodec.h"
#include "bitstream.h"
#include "mpegvideo.h"
#include "msmpeg4data.h"
#include "intrax8huf.h"
#include "intrax8.h"
#define MAX_TABLE_DEPTH(table_bits, max_bits) ((max_bits+table_bits-1)/table_bits)
#define DC_VLC_BITS 9
#define AC_VLC_BITS 9
#define OR_VLC_BITS 7
#define DC_VLC_MTD MAX_TABLE_DEPTH(DC_VLC_BITS, MAX_DC_VLC_BITS)
#define AC_VLC_MTD MAX_TABLE_DEPTH(AC_VLC_BITS, MAX_AC_VLC_BITS)
#define OR_VLC_MTD MAX_TABLE_DEPTH(OR_VLC_BITS, MAX_OR_VLC_BITS)
static VLC j_ac_vlc[2][2][8]; //[quant<13],[intra/inter],[select]
static VLC j_dc_vlc[2][8]; //[quant], [select]
static VLC j_orient_vlc[2][4]; //[quant], [select]
static void x8_vlc_init(){
int i;
#define init_ac_vlc(dst,src) \
init_vlc(&dst, \
AC_VLC_BITS,77, \
&src[1],4,2, \
&src[0],4,2, \
1)
//set ac tables
for(i=0;i<8;i++){
init_ac_vlc( j_ac_vlc[0][0][i], x8_ac0_highquant_table[i][0] );
init_ac_vlc( j_ac_vlc[0][1][i], x8_ac1_highquant_table[i][0] );
init_ac_vlc( j_ac_vlc[1][0][i], x8_ac0_lowquant_table [i][0] );
init_ac_vlc( j_ac_vlc[1][1][i], x8_ac1_lowquant_table [i][0] );
}
#undef init_ac_vlc
//set dc tables
#define init_dc_vlc(dst,src) \
init_vlc(&dst, \
DC_VLC_BITS,34, \
&src[1],4,2, \
&src[0],4,2, \
1);
for(i=0;i<8;i++){
init_dc_vlc( j_dc_vlc[0][i], x8_dc_highquant_table[i][0]);
init_dc_vlc( j_dc_vlc[1][i], x8_dc_lowquant_table [i][0]);
}
#undef init_dc_vlc
//set orient tables
#define init_or_vlc(dst,src) \
init_vlc(&dst, \
OR_VLC_BITS,12, \
&src[1],4,2, \
&src[0],4,2, \
1);
for(i=0;i<2;i++){
init_or_vlc( j_orient_vlc[0][i], x8_orient_highquant_table[i][0]);
}
for(i=0;i<4;i++){
init_or_vlc( j_orient_vlc[1][i], x8_orient_lowquant_table [i][0])
}
}
#undef init_or_vlc
static void x8_reset_vlc_tables(IntraX8Context * w){
memset(w->j_dc_vlc,0,sizeof(w->j_dc_vlc));
memset(w->j_ac_vlc,0,sizeof(w->j_ac_vlc));
w->j_orient_vlc=NULL;
}
static inline void x8_select_ac_table(IntraX8Context * const w , int mode){
MpegEncContext * const s= w->s;
int table_index;
assert(mode<4);
if( w->j_ac_vlc[mode] ) return;
table_index = get_bits(&s->gb, 3);
w->j_ac_vlc[mode] = &j_ac_vlc[w->quant<13][mode>>1][table_index];//2 modes use same tables
assert(w->j_ac_vlc[mode]);
}
static inline int x8_get_orient_vlc(IntraX8Context * w){
MpegEncContext * const s= w->s;
int table_index;
if(!w->j_orient_vlc ){
table_index = get_bits(&s->gb, 1+(w->quant<13) );
w->j_orient_vlc = &j_orient_vlc[w->quant<13][table_index];
}
assert(w->j_orient_vlc);
assert(w->j_orient_vlc->table);
return get_vlc2(&s->gb, w->j_orient_vlc->table, OR_VLC_BITS, OR_VLC_MTD);
}
#define extra_bits(eb) (eb)
#define extra_run (0xFF<<8)
#define extra_level (0x00<<8)
#define run_offset(r) ((r)<<16)
#define level_offset(l) ((l)<<24)
static const uint32_t ac_decode_table[]={
/*46*/ extra_bits(3) | extra_run | run_offset(16) | level_offset( 0),
/*47*/ extra_bits(3) | extra_run | run_offset(24) | level_offset( 0),
/*48*/ extra_bits(2) | extra_run | run_offset( 4) | level_offset( 1),
/*49*/ extra_bits(3) | extra_run | run_offset( 8) | level_offset( 1),
/*50*/ extra_bits(5) | extra_run | run_offset(32) | level_offset( 0),
/*51*/ extra_bits(4) | extra_run | run_offset(16) | level_offset( 1),
/*52*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset( 4),
/*53*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset( 8),
/*54*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset(12),
/*55*/ extra_bits(3) | extra_level | run_offset( 0) | level_offset(16),
/*56*/ extra_bits(3) | extra_level | run_offset( 0) | level_offset(24),
/*57*/ extra_bits(2) | extra_level | run_offset( 1) | level_offset( 3),
/*58*/ extra_bits(3) | extra_level | run_offset( 1) | level_offset( 7),
/*59*/ extra_bits(2) | extra_run | run_offset(16) | level_offset( 0),
/*60*/ extra_bits(2) | extra_run | run_offset(20) | level_offset( 0),
/*61*/ extra_bits(2) | extra_run | run_offset(24) | level_offset( 0),
/*62*/ extra_bits(2) | extra_run | run_offset(28) | level_offset( 0),
/*63*/ extra_bits(4) | extra_run | run_offset(32) | level_offset( 0),
/*64*/ extra_bits(4) | extra_run | run_offset(48) | level_offset( 0),
/*65*/ extra_bits(2) | extra_run | run_offset( 4) | level_offset( 1),
/*66*/ extra_bits(3) | extra_run | run_offset( 8) | level_offset( 1),
/*67*/ extra_bits(4) | extra_run | run_offset(16) | level_offset( 1),
/*68*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset( 4),
/*69*/ extra_bits(3) | extra_level | run_offset( 0) | level_offset( 8),
/*70*/ extra_bits(4) | extra_level | run_offset( 0) | level_offset(16),
/*71*/ extra_bits(2) | extra_level | run_offset( 1) | level_offset( 3),
/*72*/ extra_bits(3) | extra_level | run_offset( 1) | level_offset( 7),
};
//extra_bits = 3bits; extra_run/level = 1 bit; run_offset = 6bits; level_offset = 5 bits;
#undef extra_bits
#undef extra_run
#undef extra_level
#undef run_offset
#undef level_offset
static void x8_get_ac_rlf(IntraX8Context * const w, const int mode,
int * const run, int * const level, int * const final){
MpegEncContext * const s= w->s;
int i,e;
// x8_select_ac_table(w,mode);
i = get_vlc2(&s->gb, w->j_ac_vlc[mode]->table, AC_VLC_BITS, AC_VLC_MTD);
if(i<46){ //[0-45]
int t,l;
if(i<0){
(*level)=(*final)=//prevent 'may be used unilitialized'
(*run)=64;//this would cause error exit in the ac loop
return;
}
(*final) = t = (i>22);
i-=23*t;
/*
i== 0-15 r=0-15 l=0 ;r=i& %01111
i==16-19 r=0-3 l=1 ;r=i& %00011
i==20-21 r=0-1 l=2 ;r=i& %00001
i==22 r=0 l=3 ;r=i& %00000
l=lut_l[i/2]={0,0,0,0,0,0,0,0,1,1,2,3}[i>>1];// 11 10'01 01'00 00'00 00'00 00'00 00 => 0xE50000
t=lut_mask[l]={0x0f,0x03,0x01,0x00}[l]; as i<256 the higher bits do not matter */
l=(0xE50000>>(i&(0x1E)))&3;/*0x1E or (~1) or ((i>>1)<<1)*/
t=(0x01030F>>(l<<3));
(*run) = i&t;
(*level) = l;
}else if(i<73){//[46-72]
uint32_t sm;
uint32_t mask;
i-=46;
sm=ac_decode_table[i];
e=get_bits(&s->gb,sm&0xF);sm>>=8;//3bits
mask=sm&0xff;sm>>=8; //1bit
(*run) =(sm&0xff) + (e&( mask));//6bits
(*level)=(sm>>8) + (e&(~mask));//5bits
(*final)=i>(58-46);
}else if(i<75){//[73-74]
static const uint8_t crazy_mix_runlevel[32]={
0x22,0x32,0x33,0x53,0x23,0x42,0x43,0x63,
0x24,0x52,0x34,0x73,0x25,0x62,0x44,0x83,
0x26,0x72,0x35,0x54,0x27,0x82,0x45,0x64,
0x28,0x92,0x36,0x74,0x29,0xa2,0x46,0x84};
(*final)=!(i&1);
e=get_bits(&s->gb,5);//get the extra bits
(*run) =crazy_mix_runlevel[e]>>4;
(*level)=crazy_mix_runlevel[e]&0x0F;
}else{
(*level)=get_bits( &s->gb, 7-3*(i&1));
(*run) =get_bits( &s->gb, 6);
(*final)=get_bits1(&s->gb);
}
return;
}
//static const uint8_t dc_extra_sbits[] ={0, 1,1, 1,1, 2,2, 3,3, 4,4, 5,5, 6,6, 7,7 };
static const uint8_t dc_index_offset[] ={ 0, 1,2, 3,4, 5,7, 9,13, 17,25, 33,49, 65,97, 129,193};
static int x8_get_dc_rlf(IntraX8Context * const w,int const mode, int * const level, int * const final){
MpegEncContext * const s= w->s;
int i,e,c;
assert(mode<3);
if( !w->j_dc_vlc[mode] ) {
int table_index;
table_index = get_bits(&s->gb, 3);
//4 modes, same table
w->j_dc_vlc[mode]= &j_dc_vlc[w->quant<13][table_index];
}
assert(w->j_dc_vlc);
assert(w->j_dc_vlc[mode]->table);
i=get_vlc2(&s->gb, w->j_dc_vlc[mode]->table, DC_VLC_BITS, DC_VLC_MTD);
/*(i>=17) {i-=17;final=1;}*/
c= i>16;
(*final)=c;
i-=17*c;
if(i<=0){
(*level)=0;
return -i;
}
c=(i+1)>>1;//hackish way to calculate dc_extra_sbits[]
c-=c>1;
e=get_bits(&s->gb,c);//get the extra bits
i=dc_index_offset[i]+(e>>1);
e= -(e & 1);//0,0xffffff
(*level)= (i ^ e) - e;// (i^0)-0 , (i^0xff)-(-1)
return 0;
}
//end of huffman
static int x8_setup_spatial_predictor(IntraX8Context * const w, const int chroma){
MpegEncContext * const s= w->s;
int range;
int sum;
int quant;
s->dsp.x8_setup_spatial_compensation(s->dest[chroma], s->edge_emu_buffer,
s->current_picture.linesize[chroma>0],
&range, &sum, w->edges);
if(chroma){
w->orient=w->chroma_orient;
quant=w->quant_dc_chroma;
}else{
quant=w->quant;
}
w->flat_dc=0;
if(range < quant || range < 3){
w->orient=0;
if(range < 3){//yep you read right, a +-1 idct error may break decoding!
w->flat_dc=1;
sum+=9;
w->predicted_dc = (sum*6899)>>17;//((1<<17)+9)/(8+8+1+2)=6899
}
}
if(chroma)
return 0;
assert(w->orient < 3);
if(range < 2*w->quant){
if( (w->edges&3) == 0){
if(w->orient==1) w->orient=11;
if(w->orient==2) w->orient=10;
}else{
w->orient=0;
}
w->raw_orient=0;
}else{
static const uint8_t prediction_table[3][12]={
{0,8,4, 10,11, 2,6,9,1,3,5,7},
{4,0,8, 11,10, 3,5,2,6,9,1,7},
{8,0,4, 10,11, 1,7,2,6,9,3,5}
};
w->raw_orient=x8_get_orient_vlc(w);
if(w->raw_orient<0) return -1;
assert(w->raw_orient < 12 );
assert(w->orient<3);
w->orient=prediction_table[w->orient][w->raw_orient];
}
return 0;
}
static void x8_update_predictions(IntraX8Context * const w, const int orient, const int est_run ){
MpegEncContext * const s= w->s;
w->prediction_table[s->mb_x*2+(s->mb_y&1)] = (est_run<<2) + 1*(orient==4) + 2*(orient==8);
/*
y=2n+0 ->//0 2 4
y=2n+1 ->//1 3 5
*/
}
static void x8_get_prediction_chroma(IntraX8Context * const w){
MpegEncContext * const s= w->s;
w->edges = 1*( !(s->mb_x>>1) );
w->edges|= 2*( !(s->mb_y>>1) );
w->edges|= 4*( s->mb_x >= (2*s->mb_width-1) );//mb_x for chroma would always be odd
w->raw_orient=0;
if(w->edges&3){//lut_co[8]={inv,4,8,8, inv,4,8,8}<- =>{1,1,0,0;1,1,0,0} => 0xCC
w->chroma_orient=4<<((0xCC>>w->edges)&1);
return;
}
w->chroma_orient = (w->prediction_table[2*s->mb_x-2] & 0x03)<<2;//block[x-1][y|1-1)]
}
static void x8_get_prediction(IntraX8Context * const w){
MpegEncContext * const s= w->s;
int a,b,c,i;
w->edges = 1*( !s->mb_x );
w->edges|= 2*( !s->mb_y );
w->edges|= 4*( s->mb_x >= (2*s->mb_width-1) );
switch(w->edges&3){
case 0:
break;
case 1:
//take the one from the above block[0][y-1]
w->est_run = w->prediction_table[!(s->mb_y&1)]>>2;
w->orient = 1;
return;
case 2:
//take the one from the previous block[x-1][0]
w->est_run = w->prediction_table[2*s->mb_x-2]>>2;
w->orient = 2;
return;
case 3:
w->est_run = 16;
w->orient = 0;
return;
}
//no edge cases
b= w->prediction_table[2*s->mb_x + !(s->mb_y&1) ];//block[x ][y-1]
a= w->prediction_table[2*s->mb_x-2 + (s->mb_y&1) ];//block[x-1][y ]
c= w->prediction_table[2*s->mb_x-2 + !(s->mb_y&1) ];//block[x-1][y-1]
w->est_run = FFMIN(b,a);
/* This condition has nothing to do with w->edges, even if it looks
similar it would trigger if e.g. x=3;y=2;
I guess somebody wrote something wrong and it became standard. */
if( (s->mb_x & s->mb_y) != 0 ) w->est_run=FFMIN(c,w->est_run);
w->est_run>>=2;
a&=3;
b&=3;
c&=3;
i=( 0xFFEAF4C4>>(2*b+8*a) )&3;
if(i!=3) w->orient=i;
else w->orient=( 0xFFEAD8>>(2*c+8*(w->quant>12)) )&3;
/*
lut1[b][a]={
->{0, 1, 0, pad},
{0, 1, X, pad},
{2, 2, 2, pad}}
pad 2 2 2; pad X 1 0; pad 0 1 0 <-
-> 11 10 '10 10 '11 11'01 00 '11 00'01 00=>0xEAF4C4
lut2[q>12][c]={
->{0,2,1,pad},
{2,2,2,pad}}
pad 2 2 2; pad 1 2 0 <-
-> 11 10'10 10 '11 01'10 00=>0xEAD8
*/
}
static void x8_ac_compensation(IntraX8Context * const w, int const direction, int const dc_level){
MpegEncContext * const s= w->s;
int t;
#define B(x,y) s->block[0][s->dsp.idct_permutation[(x)+(y)*8]]
#define T(x) ((x) * dc_level + 0x8000) >> 16;
switch(direction){
case 0:
t = T(3811);//h
B(1,0) -= t;
B(0,1) -= t;
t = T(487);//e
B(2,0) -= t;
B(0,2) -= t;
t = T(506);//f
B(3,0) -= t;
B(0,3) -= t;
t = T(135);//c
B(4,0) -= t;
B(0,4) -= t;
B(2,1) += t;
B(1,2) += t;
B(3,1) += t;
B(1,3) += t;
t = T(173);//d
B(5,0) -= t;
B(0,5) -= t;
t = T(61);//b
B(6,0) -= t;
B(0,6) -= t;
B(5,1) += t;
B(1,5) += t;
t = T(42); //a
B(7,0) -= t;
B(0,7) -= t;
B(4,1) += t;
B(1,4) += t;
B(4,4) += t;
t = T(1084);//g
B(1,1) += t;
s->block_last_index[0] = FFMAX(s->block_last_index[0], 7*8);
break;
case 1:
B(0,1) -= T(6269);
B(0,3) -= T( 708);
B(0,5) -= T( 172);
B(0,7) -= T( 73);
s->block_last_index[0] = FFMAX(s->block_last_index[0], 7*8);
break;
case 2:
B(1,0) -= T(6269);
B(3,0) -= T( 708);
B(5,0) -= T( 172);
B(7,0) -= T( 73);
s->block_last_index[0] = FFMAX(s->block_last_index[0], 7);
break;
}
#undef B
#undef T
}
static void dsp_x8_put_solidcolor(uint8_t const pix, uint8_t * dst, int const linesize){
int k;
for(k=0;k<8;k++){
memset(dst,pix,8);
dst+=linesize;
}
}
static const int16_t quant_table[64] = {
256, 256, 256, 256, 256, 256, 259, 262,
265, 269, 272, 275, 278, 282, 285, 288,
292, 295, 299, 303, 306, 310, 314, 317,
321, 325, 329, 333, 337, 341, 345, 349,
353, 358, 362, 366, 371, 375, 379, 384,
389, 393, 398, 403, 408, 413, 417, 422,
428, 433, 438, 443, 448, 454, 459, 465,
470, 476, 482, 488, 493, 499, 505, 511
};
static int x8_decode_intra_mb(IntraX8Context* const w, const int chroma){
MpegEncContext * const s= w->s;
uint8_t * scantable;
int final,run,level;
int ac_mode,dc_mode,est_run,dc_level;
int pos,n;
int zeros_only;
int use_quant_matrix;
int sign;
assert(w->orient<12);
memset(s->block[0],0x00,64*sizeof(DCTELEM));
if(chroma){
dc_mode=2;
}else{
dc_mode=!!w->est_run;//0,1
}
if(x8_get_dc_rlf(w, dc_mode, &dc_level, &final)) return -1;
n=0;
zeros_only=0;
if(!final){//decode ac
use_quant_matrix=w->use_quant_matrix;
if(chroma){
ac_mode = 1;
est_run = 64;//not used
}else{
if (w->raw_orient < 3){
use_quant_matrix = 0;
}
if(w->raw_orient > 4){
ac_mode = 0;
est_run = 64;
}else{
if(w->est_run > 1){
ac_mode = 2;
est_run=w->est_run;
}else{
ac_mode = 3;
est_run = 64;
}
}
}
x8_select_ac_table(w,ac_mode);
/*scantable_selector[12]={0,2,0,1,1,1,0,2,2,0,1,2};<-
-> 10'01' 00'10' 10'00' 01'01' 01'00' 10'00 =>0x928548 */
scantable = w->scantable[ (0x928548>>(2*w->orient))&3 ].permutated;
pos=0;
do {
n++;
if( n >= est_run ){
ac_mode=3;
x8_select_ac_table(w,3);
}
x8_get_ac_rlf(w,ac_mode,&run,&level,&final);
pos+=run+1;
if(pos>63){
//this also handles vlc error in x8_get_ac_rlf
return -1;
}
level= (level+1) * w->dquant;
level+= w->qsum;
sign = - get_bits1(&s->gb);
level = (level ^ sign) - sign;
if(use_quant_matrix){
level = (level*quant_table[pos])>>8;
}
s->block[0][ scantable[pos] ]=level;
}while(!final);
s->block_last_index[0]=pos;
}else{//DC only
s->block_last_index[0]=0;
if(w->flat_dc && ((unsigned)(dc_level+1)) < 3){//[-1;1]
int32_t divide_quant= !chroma ? w->divide_quant_dc_luma:
w->divide_quant_dc_chroma;
int32_t dc_quant = !chroma ? w->quant:
w->quant_dc_chroma;
//original intent dc_level+=predicted_dc/quant; but it got lost somewhere in the rounding
dc_level+= (w->predicted_dc*divide_quant + (1<<12) )>>13;
dsp_x8_put_solidcolor( av_clip_uint8((dc_level*dc_quant+4)>>3),
s->dest[chroma], s->current_picture.linesize[!!chroma]);
goto block_placed;
}
zeros_only = (dc_level == 0);
}
if(!chroma){
s->block[0][0] = dc_level*w->quant;
}else{
s->block[0][0] = dc_level*w->quant_dc_chroma;
}
//there is !zero_only check in the original, but dc_level check is enough
if( (unsigned int)(dc_level+1) >= 3 && (w->edges&3) != 3 ){
int direction;
/*ac_comp_direction[orient] = { 0, 3, 3, 1, 1, 0, 0, 0, 2, 2, 2, 1 };<-
-> 01'10' 10'10' 00'00' 00'01' 01'11' 11'00 =>0x6A017C */
direction= (0x6A017C>>(w->orient*2))&3;
if (direction != 3){
x8_ac_compensation(w, direction, s->block[0][0]);//modify block_last[]
}
}
if(w->flat_dc){
dsp_x8_put_solidcolor(w->predicted_dc, s->dest[chroma], s->current_picture.linesize[!!chroma]);
}else{
s->dsp.x8_spatial_compensation[w->orient]( s->edge_emu_buffer,
s->dest[chroma],
s->current_picture.linesize[!!chroma] );
}
if(!zeros_only)
s->dsp.idct_add ( s->dest[chroma],
s->current_picture.linesize[!!chroma],
s->block[0] );
block_placed:
if(!chroma){
x8_update_predictions(w,w->orient,n);
}
if(s->loop_filter){
uint8_t* ptr = s->dest[chroma];
int linesize = s->current_picture.linesize[!!chroma];
if(!( (w->edges&2) || ( zeros_only && (w->orient|4)==4 ) )){
s->dsp.x8_h_loop_filter(ptr, linesize, w->quant);
}
if(!( (w->edges&1) || ( zeros_only && (w->orient|8)==8 ) )){
s->dsp.x8_v_loop_filter(ptr, linesize, w->quant);
}
}
return 0;
}
static void x8_init_block_index(MpegEncContext *s){ //FIXME maybe merge with ff_*
//not s->linesize as this would be wrong for field pics
//not that IntraX8 has interlacing support ;)
const int linesize = s->current_picture.linesize[0];
const int uvlinesize= s->current_picture.linesize[1];
s->dest[0] = s->current_picture.data[0];
s->dest[1] = s->current_picture.data[1];
s->dest[2] = s->current_picture.data[2];
s->dest[0] += s->mb_y * linesize << 3;
s->dest[1] += ( s->mb_y&(~1) ) * uvlinesize << 2;//chroma blocks are on add rows
s->dest[2] += ( s->mb_y&(~1) ) * uvlinesize << 2;
}
/**
* Initialize IntraX8 frame decoder.
* Requires valid MpegEncContext with valid s->mb_width before calling.
* @param w pointer to IntraX8Context
* @param s pointer to MpegEncContext of the parent codec
*/
void ff_intrax8_common_init(IntraX8Context * w, MpegEncContext * const s){
w->s=s;
x8_vlc_init();
assert(s->mb_width>0);
w->prediction_table=av_mallocz(s->mb_width*2*2);//two rows, 2 blocks per cannon mb
ff_init_scantable(s->dsp.idct_permutation, &w->scantable[0], wmv1_scantable[0]);
ff_init_scantable(s->dsp.idct_permutation, &w->scantable[1], wmv1_scantable[2]);
ff_init_scantable(s->dsp.idct_permutation, &w->scantable[2], wmv1_scantable[3]);
}
/**
* Destroy IntraX8 frame structure.
* @param w pointer to IntraX8Context
*/
void ff_intrax8_common_end(IntraX8Context * w)
{
av_freep(&w->prediction_table);
}
/**
* Decode single IntraX8 frame.
* The parent codec must fill s->loopfilter and s->gb (bitstream).
* The parent codec must call MPV_frame_start(), ff_er_frame_start() before calling this function.
* The parent codec must call ff_er_frame_end(), MPV_frame_end() after calling this function.
* This function does not use MPV_decode_mb().
* lowres decoding is theoretically impossible.
* @param w pointer to IntraX8Context
* @param dquant doubled quantizer, it would be odd in case of VC-1 halfpq==1.
* @param quant_offset offset away from zero
*/
//FIXME extern uint8_t wmv3_dc_scale_table[32];
int ff_intrax8_decode_picture(IntraX8Context * const w, int dquant, int quant_offset){
MpegEncContext * const s= w->s;
int mb_xy;
assert(s);
w->use_quant_matrix = get_bits1(&s->gb);
w->dquant = dquant;
w->quant = dquant >> 1;
w->qsum = quant_offset;
w->divide_quant_dc_luma = ((1<<16) + (w->quant>>1)) / w->quant;
if(w->quant < 5){
w->quant_dc_chroma = w->quant;
w->divide_quant_dc_chroma = w->divide_quant_dc_luma;
}else{
w->quant_dc_chroma = w->quant+((w->quant+3)>>3);
w->divide_quant_dc_chroma = ((1<<16) + (w->quant_dc_chroma>>1)) / w->quant_dc_chroma;
}
x8_reset_vlc_tables(w);
s->resync_mb_x=0;
s->resync_mb_y=0;
for(s->mb_y=0; s->mb_y < s->mb_height*2; s->mb_y++){
x8_init_block_index(s);
mb_xy=(s->mb_y>>1)*s->mb_stride;
for(s->mb_x=0; s->mb_x < s->mb_width*2; s->mb_x++){
x8_get_prediction(w);
if(x8_setup_spatial_predictor(w,0)) goto error;
if(x8_decode_intra_mb(w,0)) goto error;
if( s->mb_x & s->mb_y & 1 ){
x8_get_prediction_chroma(w);
/*when setting up chroma, no vlc is read,
so no error condition can be reached*/
x8_setup_spatial_predictor(w,1);
if(x8_decode_intra_mb(w,1)) goto error;
x8_setup_spatial_predictor(w,2);
if(x8_decode_intra_mb(w,2)) goto error;
s->dest[1]+= 8;
s->dest[2]+= 8;
/*emulate MB info in the relevant tables*/
s->mbskip_table [mb_xy]=0;
s->mbintra_table[mb_xy]=1;
s->current_picture.qscale_table[mb_xy]=w->quant;
mb_xy++;
}
s->dest[0]+= 8;
}
if(s->mb_y&1){
ff_draw_horiz_band(s, (s->mb_y-1)*8, 16);
}
}
error:
ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y,
(s->mb_x>>1)-1, (s->mb_y>>1)-1,
(AC_END|DC_END|MV_END) );
return 0;
}