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quantizer noise shaping

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Originally committed as revision 2742 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Michael Niedermayer 21 years ago
parent 95ba2c8f43
commit 77ea0d4bdd
3 changed files with 485 additions and 39 deletions
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  1. 9
      ffmpeg.c
  2. 8
      libavcodec/avcodec.h
  3. 507
      libavcodec/mpegvideo.c

9
ffmpeg.c
Unescape View File

@ -125,6 +125,7 @@ static int use_umv = 0;
static int use_alt_scan = 0;
static int use_trell = 0;
static int use_scan_offset = 0;
static int qns = 0;
static int closed_gop = 0;
static int do_deinterlace = 0;
static int do_interlace_dct = 0;
@ -659,7 +660,6 @@ static void do_video_out(AVFormatContext *s,
big_picture.quality = ist->st->quality;
}else
big_picture.quality = ost->st->quality;
ret = avcodec_encode_video(enc,
video_buffer, VIDEO_BUFFER_SIZE,
&big_picture);
@ -1987,6 +1987,11 @@ static void opt_noise_reduction(const char *arg)
noise_reduction= atoi(arg);
}
static void opt_qns(const char *arg)
{
qns= atoi(arg);
}
static void opt_sc_threshold(const char *arg)
{
sc_threshold= atoi(arg);
@ -2400,6 +2405,7 @@ static void opt_output_file(const char *filename)
video_enc->ildct_cmp = ildct_cmp;
video_enc->me_sub_cmp = sub_cmp;
video_enc->me_cmp = cmp;
video_enc->quantizer_noise_shaping= qns;
if (use_umv) {
video_enc->flags |= CODEC_FLAG_H263P_UMV;
@ -3080,6 +3086,7 @@ const OptionDef options[] = {
{ "inter_matrix", HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)opt_inter_matrix}, "specify inter matrix coeffs", "matrix" },
{ "top", HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)opt_top_field_first}, "top=1/bottom=0/auto=-1 field first", "" },
{ "nr", HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)opt_noise_reduction}, "noise reduction", "" },
{ "qns", HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)opt_qns}, "quantization noise shaping", "" },
{ "sc_threshold", HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)opt_sc_threshold}, "scene change threshold", "threshold" },
/* audio options */

8
libavcodec/avcodec.h
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@ -17,7 +17,7 @@ extern "C" {
#define FFMPEG_VERSION_INT 0x000408
#define FFMPEG_VERSION "0.4.8"
#define LIBAVCODEC_BUILD 4699
#define LIBAVCODEC_BUILD 4700
#define LIBAVCODEC_VERSION_INT FFMPEG_VERSION_INT
#define LIBAVCODEC_VERSION FFMPEG_VERSION
@ -1504,6 +1504,12 @@ typedef struct AVCodecContext {
#define FF_AA_FASTINT 1 //not implemented yet
#define FF_AA_INT 2
#define FF_AA_FLOAT 3
/**
* Quantizer noise shaping.
* - encoding: set by user
* - decoding: unused
*/
int quantizer_noise_shaping;
} AVCodecContext;

507
libavcodec/mpegvideo.c
Unescape View File

@ -26,6 +26,7 @@
*/
#include <limits.h>
#include <math.h> //for PI
#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
@ -57,6 +58,7 @@ static void draw_edges_c(uint8_t *buf, int wrap, int width, int height, int w);
#ifdef CONFIG_ENCODERS
static int dct_quantize_c(MpegEncContext *s, DCTELEM *block, int n, int qscale, int *overflow);
static int dct_quantize_trellis_c(MpegEncContext *s, DCTELEM *block, int n, int qscale, int *overflow);
static int dct_quantize_refine(MpegEncContext *s, DCTELEM *block, int16_t *weight, DCTELEM *orig, int n, int qscale);
static int sse_mb(MpegEncContext *s);
static void denoise_dct_c(MpegEncContext *s, DCTELEM *block);
#endif //CONFIG_ENCODERS
@ -3264,8 +3266,33 @@ void ff_init_block_index(MpegEncContext *s){ //FIXME maybe rename
#ifdef CONFIG_ENCODERS
static void get_vissual_weight(int16_t *weight, uint8_t *ptr, int stride){
int x, y;
//FIXME optimize
for(y=0; y<8; y++){
for(x=0; x<8; x++){
int x2, y2;
int sum=0;
int sqr=0;
int count=0;
for(y2= FFMAX(y-1, 0); y2 < FFMIN(8, y+2); y2++){
for(x2= FFMAX(x-1, 0); x2 < FFMIN(8, x+2); x2++){
int v= ptr[x2 + y2*stride];
sum += v;
sqr += v*v;
count++;
}
}
weight[x + 8*y]= (36*ff_sqrt(count*sqr - sum*sum)) / count;
}
}
}
static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
{
int16_t weight[6][64];
DCTELEM orig[6][64];
const int mb_x= s->mb_x;
const int mb_y= s->mb_y;
int i;
@ -3298,16 +3325,19 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
}
if (s->mb_intra) {
uint8_t *ptr;
int wrap_y;
uint8_t *ptr_y, *ptr_cb, *ptr_cr;
int wrap_y, wrap_c;
int emu=0;
wrap_y = s->linesize;
ptr = s->new_picture.data[0] + (mb_y * 16 * wrap_y) + mb_x * 16;
wrap_c = s->uvlinesize;
ptr_y = s->new_picture.data[0] + (mb_y * 16 * wrap_y) + mb_x * 16;
ptr_cb = s->new_picture.data[1] + (mb_y * 8 * wrap_c) + mb_x * 8;
ptr_cr = s->new_picture.data[2] + (mb_y * 8 * wrap_c) + mb_x * 8;
if(mb_x*16+16 > s->width || mb_y*16+16 > s->height){
ff_emulated_edge_mc(s->edge_emu_buffer, ptr, wrap_y, 16, 16, mb_x*16, mb_y*16, s->width, s->height);
ptr= s->edge_emu_buffer;
ff_emulated_edge_mc(s->edge_emu_buffer, ptr_y, wrap_y, 16, 16, mb_x*16, mb_y*16, s->width, s->height);
ptr_y= s->edge_emu_buffer;
emu=1;
}
@ -3315,12 +3345,12 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
int progressive_score, interlaced_score;
s->interlaced_dct=0;
progressive_score= s->dsp.ildct_cmp[4](s, ptr , NULL, wrap_y, 8)
+s->dsp.ildct_cmp[4](s, ptr + wrap_y*8, NULL, wrap_y, 8) - 400;
progressive_score= s->dsp.ildct_cmp[4](s, ptr_y , NULL, wrap_y, 8)
+s->dsp.ildct_cmp[4](s, ptr_y + wrap_y*8, NULL, wrap_y, 8) - 400;
if(progressive_score > 0){
interlaced_score = s->dsp.ildct_cmp[4](s, ptr , NULL, wrap_y*2, 8)
+s->dsp.ildct_cmp[4](s, ptr + wrap_y , NULL, wrap_y*2, 8);
interlaced_score = s->dsp.ildct_cmp[4](s, ptr_y , NULL, wrap_y*2, 8)
+s->dsp.ildct_cmp[4](s, ptr_y + wrap_y , NULL, wrap_y*2, 8);
if(progressive_score > interlaced_score){
s->interlaced_dct=1;
@ -3330,29 +3360,36 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
}
}
s->dsp.get_pixels(s->block[0], ptr , wrap_y);
s->dsp.get_pixels(s->block[1], ptr + 8, wrap_y);
s->dsp.get_pixels(s->block[2], ptr + dct_offset , wrap_y);
s->dsp.get_pixels(s->block[3], ptr + dct_offset + 8, wrap_y);
s->dsp.get_pixels(s->block[0], ptr_y , wrap_y);
s->dsp.get_pixels(s->block[1], ptr_y + 8, wrap_y);
s->dsp.get_pixels(s->block[2], ptr_y + dct_offset , wrap_y);
s->dsp.get_pixels(s->block[3], ptr_y + dct_offset + 8, wrap_y);
if(s->flags&CODEC_FLAG_GRAY){
skip_dct[4]= 1;
skip_dct[5]= 1;
}else{
int wrap_c = s->uvlinesize;
ptr = s->new_picture.data[1] + (mb_y * 8 * wrap_c) + mb_x * 8;
if(emu){
ff_emulated_edge_mc(s->edge_emu_buffer, ptr, wrap_c, 8, 8, mb_x*8, mb_y*8, s->width>>1, s->height>>1);
ptr= s->edge_emu_buffer;
ff_emulated_edge_mc(s->edge_emu_buffer, ptr_cb, wrap_c, 8, 8, mb_x*8, mb_y*8, s->width>>1, s->height>>1);
ptr_cb= s->edge_emu_buffer;
}
s->dsp.get_pixels(s->block[4], ptr, wrap_c);
s->dsp.get_pixels(s->block[4], ptr_cb, wrap_c);
ptr = s->new_picture.data[2] + (mb_y * 8 * wrap_c) + mb_x * 8;
if(emu){
ff_emulated_edge_mc(s->edge_emu_buffer, ptr, wrap_c, 8, 8, mb_x*8, mb_y*8, s->width>>1, s->height>>1);
ptr= s->edge_emu_buffer;
ff_emulated_edge_mc(s->edge_emu_buffer, ptr_cr, wrap_c, 8, 8, mb_x*8, mb_y*8, s->width>>1, s->height>>1);
ptr_cr= s->edge_emu_buffer;
}
s->dsp.get_pixels(s->block[5], ptr, wrap_c);
s->dsp.get_pixels(s->block[5], ptr_cr, wrap_c);
}
if(s->avctx->quantizer_noise_shaping){
get_vissual_weight(weight[0], ptr_y , wrap_y);
get_vissual_weight(weight[1], ptr_y + 8, wrap_y);
get_vissual_weight(weight[2], ptr_y + dct_offset , wrap_y);
get_vissual_weight(weight[3], ptr_y + dct_offset + 8, wrap_y);
get_vissual_weight(weight[4], ptr_cb , wrap_c);
get_vissual_weight(weight[5], ptr_cr , wrap_c);
memcpy(orig[0], s->block[0], sizeof(DCTELEM)*64*6);
}
}else{
op_pixels_func (*op_pix)[4];
@ -3445,23 +3482,17 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
if(s->dsp.sad[1](NULL, ptr_y +dct_offset+ 8, dest_y +dct_offset+ 8, wrap_y, 8) < 20*s->qscale) skip_dct[3]= 1;
if(s->dsp.sad[1](NULL, ptr_cb , dest_cb , wrap_c, 8) < 20*s->qscale) skip_dct[4]= 1;
if(s->dsp.sad[1](NULL, ptr_cr , dest_cr , wrap_c, 8) < 20*s->qscale) skip_dct[5]= 1;
#if 0
{
static int stat[7];
int num=0;
for(i=0; i<6; i++)
if(skip_dct[i]) num++;
stat[num]++;
if(s->mb_x==0 && s->mb_y==0){
for(i=0; i<7; i++){
printf("%6d %1d\n", stat[i], i);
}
}
}
#endif
}
if(s->avctx->quantizer_noise_shaping){
if(!skip_dct[0]) get_vissual_weight(weight[0], ptr_y , wrap_y);
if(!skip_dct[1]) get_vissual_weight(weight[1], ptr_y + 8, wrap_y);
if(!skip_dct[2]) get_vissual_weight(weight[2], ptr_y + dct_offset , wrap_y);
if(!skip_dct[3]) get_vissual_weight(weight[3], ptr_y + dct_offset + 8, wrap_y);
if(!skip_dct[4]) get_vissual_weight(weight[4], ptr_cb , wrap_c);
if(!skip_dct[5]) get_vissual_weight(weight[5], ptr_cr , wrap_c);
memcpy(orig[0], s->block[0], sizeof(DCTELEM)*64*6);
}
}
/* DCT & quantize */
@ -3483,6 +3514,13 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
}else
s->block_last_index[i]= -1;
}
if(s->avctx->quantizer_noise_shaping){
for(i=0;i<6;i++) {
if(!skip_dct[i]){
s->block_last_index[i] = dct_quantize_refine(s, s->block[i], weight[i], orig[i], i, s->qscale);
}
}
}
if(s->luma_elim_threshold && !s->mb_intra)
for(i=0; i<4; i++)
@ -4911,6 +4949,401 @@ static int dct_quantize_trellis_c(MpegEncContext *s,
return last_non_zero;
}
#define BASIS_SHIFT 16
#define RECON_SHIFT 6
//#define REFINE_STATS 1
static int16_t basis[64][64];
static void build_basis(uint8_t *perm){
int i, j, x, y;
emms_c();
for(i=0; i<8; i++){
for(j=0; j<8; j++){
for(y=0; y<8; y++){
for(x=0; x<8; x++){
double s= 0.25*(1<<BASIS_SHIFT);
int index= 8*i + j;
int perm_index= perm[index];
if(i==0) s*= sqrt(0.5);
if(j==0) s*= sqrt(0.5);
basis[perm_index][8*x + y]= lrintf(s * cos((M_PI/8.0)*i*(x+0.5)) * cos((M_PI/8.0)*j*(y+0.5)));
}
}
}
}
}
static int try_basis(int16_t rem[64], int16_t weight[64], int index, int scale){
int i;
unsigned int sum=0;
for(i=0; i<8*8; i++){
int b= rem[i] - ((basis[index][i]*scale + (1<<(BASIS_SHIFT - RECON_SHIFT-1)))>>(BASIS_SHIFT - RECON_SHIFT));
int w= weight[i];
b= (b + (1<<(RECON_SHIFT-1))) >> RECON_SHIFT;
assert(-512<b && b<512);
sum += (w*b)*(w*b)>>4;
}
return sum>>2;
}
static void add_basis(int16_t rem[64], int index, int scale){
int i;
for(i=0; i<8*8; i++){
rem[i] -= (basis[index][i]*scale + (1<<(BASIS_SHIFT - RECON_SHIFT-1)))>>(BASIS_SHIFT - RECON_SHIFT);
}
}
static int dct_quantize_refine(MpegEncContext *s, //FIXME breaks denoise?
DCTELEM *block, int16_t *weight, DCTELEM *orig,
int n, int qscale){
int16_t rem[64];
const int *qmat;
const uint8_t *scantable= s->intra_scantable.scantable;
const uint8_t *perm_scantable= s->intra_scantable.permutated;
// unsigned int threshold1, threshold2;
// int bias=0;
int run_tab[65];
int prev_run=0;
int prev_level=0;
int qmul, qadd, start_i, last_non_zero, i, dc;
const int esc_length= s->ac_esc_length;
uint8_t * length;
uint8_t * last_length;
int lambda;
int rle_index, run, q, sum;
#ifdef REFINE_STATS
static int count=0;
static int after_last=0;
static int to_zero=0;
static int from_zero=0;
static int raise=0;
static int lower=0;
static int messed_sign=0;
#endif
if(basis[0][0] == 0)
build_basis(s->dsp.idct_permutation);
qmul= qscale*2;
qadd= (qscale-1)|1;
if (s->mb_intra) {
if (!s->h263_aic) {
if (n < 4)
q = s->y_dc_scale;
else
q = s->c_dc_scale;
} else{
/* For AIC we skip quant/dequant of INTRADC */
q = 1;
qadd=0;
}
q <<= RECON_SHIFT-3;
/* note: block[0] is assumed to be positive */
dc= block[0]*q;
// block[0] = (block[0] + (q >> 1)) / q;
start_i = 1;
qmat = s->q_intra_matrix[qscale];
// if(s->mpeg_quant || s->out_format == FMT_MPEG1)
// bias= 1<<(QMAT_SHIFT-1);
length = s->intra_ac_vlc_length;
last_length= s->intra_ac_vlc_last_length;
} else {
dc= 0;
start_i = 0;
qmat = s->q_inter_matrix[qscale];
length = s->inter_ac_vlc_length;
last_length= s->inter_ac_vlc_last_length;
}
last_non_zero = s->block_last_index[n];
#ifdef REFINE_STATS
{START_TIMER
#endif
for(i=0; i<64; i++){ //FIXME memsetw or similar
rem[i]= (orig[i]<<RECON_SHIFT) - dc; //FIXME use orig dirrectly insteadof copying to rem[]
}
#ifdef REFINE_STATS
STOP_TIMER("memset rem[]")}
#endif
sum=0;
for(i=0; i<64; i++){
int one= 36;
int qns=4;
int w;
w= ABS(weight[i]) + qns*one;
w= 15 + (48*qns*one + w/2)/w; // 16 .. 63
weight[i] = w;
// w=weight[i] = (63*qns + (w/2)) / w;
assert(w>0);
assert(w<(1<<6));
sum += w*w;
}
lambda= sum*(uint64_t)s->lambda2 >> (FF_LAMBDA_SHIFT - 6 + 6 + 6 + 6);
#ifdef REFINE_STATS
{START_TIMER
#endif
run=0;
rle_index=0;
for(i=start_i; i<=last_non_zero; i++){
int j= perm_scantable[i];
const int level= block[j];
int coeff;
if(level){
if(level<0) coeff= qmul*level - qadd;
else coeff= qmul*level + qadd;
run_tab[rle_index++]=run;
run=0;
add_basis(rem, j, coeff);
}else{
run++;
}
}
#ifdef REFINE_STATS
if(last_non_zero>0){
STOP_TIMER("init rem[]")
}
}
{START_TIMER
#endif
for(;;){
int best_score=try_basis(rem, weight, 0, 0);
int nochange_score= best_score;
int best_coeff=0;
int best_change=0;
int run2, best_unquant_change;
#ifdef REFINE_STATS
{START_TIMER
#endif
if(start_i){
const int level= block[0];
int change, old_coeff;
assert(s->mb_intra);
old_coeff= q*level;
for(change=-1; change<=1; change+=2){
int new_level= level + change;
int score, new_coeff;
new_coeff= q*new_level;
if(new_coeff >= 2048 || new_coeff < 0)
continue;
score= try_basis(rem, weight, 0, new_coeff - old_coeff);
if(score<best_score){
best_score= score;
best_coeff= 0;
best_change= change;
best_unquant_change= new_coeff - old_coeff;
}
}
}
run=0;
rle_index=0;
run2= run_tab[rle_index++];
prev_level=0;
prev_run=0;
for(i=start_i; i<64; i++){
int j= perm_scantable[i];
const int level= block[j];
int change, old_coeff;
if(s->avctx->quantizer_noise_shaping < 3 && i > last_non_zero + 1)
break;
if(level){
if(level<0) old_coeff= qmul*level - qadd;
else old_coeff= qmul*level + qadd;
run2= run_tab[rle_index++]; //FIXME ! maybe after last
}else{
old_coeff=0;
run2--;
assert(run2>=0 || i >= last_non_zero );
}
for(change=-1; change<=1; change+=2){
int new_level= level + change;
int score, new_coeff, unquant_change;
score=0;
if(s->avctx->quantizer_noise_shaping < 2 && ABS(new_level) > ABS(level))
continue;
if(new_level){
if(new_level<0) new_coeff= qmul*new_level - qadd;
else new_coeff= qmul*new_level + qadd;
if(new_coeff >= 2048 || new_coeff <= -2048)
continue;
//FIXME check for overflow
if(level){
if(level < 63 && level > -63){
if(i < last_non_zero)
score += length[UNI_AC_ENC_INDEX(run, new_level+64)]
- length[UNI_AC_ENC_INDEX(run, level+64)];
else
score += last_length[UNI_AC_ENC_INDEX(run, new_level+64)]
- last_length[UNI_AC_ENC_INDEX(run, level+64)];
}
}else{
assert(ABS(new_level)==1);
if(i < last_non_zero){
int next_i= i + run2 + 1;
int next_level= block[ perm_scantable[next_i] ] + 64;
if(next_level&(~127))
next_level= 0;
if(next_i < last_non_zero)
score += length[UNI_AC_ENC_INDEX(run, 65)]
+ length[UNI_AC_ENC_INDEX(run2, next_level)]
- length[UNI_AC_ENC_INDEX(run + run2 + 1, next_level)];
else
score += length[UNI_AC_ENC_INDEX(run, 65)]
+ last_length[UNI_AC_ENC_INDEX(run2, next_level)]
- last_length[UNI_AC_ENC_INDEX(run + run2 + 1, next_level)];
}else{
score += last_length[UNI_AC_ENC_INDEX(run, 65)];
if(prev_level){
score += length[UNI_AC_ENC_INDEX(prev_run, prev_level)]
- last_length[UNI_AC_ENC_INDEX(prev_run, prev_level)];
}
}
}
}else{
new_coeff=0;
assert(ABS(level)==1);
if(i < last_non_zero){
int next_i= i + run2 + 1;
int next_level= block[ perm_scantable[next_i] ] + 64;
if(next_level&(~127))
next_level= 0;
if(next_i < last_non_zero)
score += length[UNI_AC_ENC_INDEX(run + run2 + 1, next_level)]
- length[UNI_AC_ENC_INDEX(run2, next_level)]
- length[UNI_AC_ENC_INDEX(run, 65)];
else
score += last_length[UNI_AC_ENC_INDEX(run + run2 + 1, next_level)]
- last_length[UNI_AC_ENC_INDEX(run2, next_level)]
- length[UNI_AC_ENC_INDEX(run, 65)];
}else{
score += -last_length[UNI_AC_ENC_INDEX(run, 65)];
if(prev_level){
score += last_length[UNI_AC_ENC_INDEX(prev_run, prev_level)]
- length[UNI_AC_ENC_INDEX(prev_run, prev_level)];
}
}
}
score *= lambda;
unquant_change= new_coeff - old_coeff;
assert((score < 100*lambda && score > -100*lambda) || lambda==0);
score+= try_basis(rem, weight, j, unquant_change);
if(score<best_score){
best_score= score;
best_coeff= i;
best_change= change;
best_unquant_change= unquant_change;
}
}
if(level){
prev_level= level + 64;
if(prev_level&(~127))
prev_level= 0;
prev_run= run;
run=0;
}else{
run++;
}
}
#ifdef REFINE_STATS
STOP_TIMER("iterative step")}
#endif
if(best_change){
int j= perm_scantable[ best_coeff ];
block[j] += best_change;
if(best_coeff > last_non_zero){
last_non_zero= best_coeff;
assert(block[j]);
#ifdef REFINE_STATS
after_last++;
#endif
}else{
#ifdef REFINE_STATS
if(block[j]){
if(block[j] - best_change){
if(ABS(block[j]) > ABS(block[j] - best_change)){
raise++;
}else{
lower++;
}
}else{
from_zero++;
}
}else{
to_zero++;
}
#endif
for(; last_non_zero>=start_i; last_non_zero--){
if(block[perm_scantable[last_non_zero]])
break;
}
}
#ifdef REFINE_STATS
count++;
if(256*256*256*64 % count == 0){
printf("after_last:%d to_zero:%d from_zero:%d raise:%d lower:%d sign:%d xyp:%d/%d/%d\n", after_last, to_zero, from_zero, raise, lower, messed_sign, s->mb_x, s->mb_y, s->picture_number);
}
#endif
run=0;
rle_index=0;
for(i=start_i; i<=last_non_zero; i++){
int j= perm_scantable[i];
const int level= block[j];
if(level){
run_tab[rle_index++]=run;
run=0;
}else{
run++;
}
}
add_basis(rem, j, best_unquant_change);
}else{
break;
}
}
#ifdef REFINE_STATS
if(last_non_zero>0){
STOP_TIMER("iterative search")
}
}
#endif
return last_non_zero;
}
static int dct_quantize_c(MpegEncContext *s,
DCTELEM *block, int n,
int qscale, int *overflow)

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