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20% less memory needed for 8bit AC state (worst compression rate loss was 0.2%, all other files had <=0.1% loss)

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Originally committed as revision 2000 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2003-07-02 10:45:04 +00:00
parent 9085af0751
commit 085565f71f
1 changed files with 68 additions and 47 deletions
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115
libavcodec/ffv1.c
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@ -209,7 +209,7 @@ static inline int get_context(FFV1Context *f, uint8_t *src, uint8_t *last, uint8
/**
* put
*/
static inline void put_symbol(CABACContext *c, uint8_t *state, int v, int is_signed){
static inline void put_symbol(CABACContext *c, uint8_t *state, int v, int is_signed, int max_exp){
int i;
if(v){
@ -217,42 +217,46 @@ static inline void put_symbol(CABACContext *c, uint8_t *state, int v, int is_sig
const int e= av_log2(a);
put_cabac(c, state+0, 0);
put_cabac_u(c, state+1, e, 7, 6, 1); //1..7
if(e<7){
for(i=0; i<e; i++){
put_cabac(c, state+1+i, 1); //1..8
}
if(e<max_exp){
put_cabac(c, state+1+i, 0); //1..8
for(i=e-1; i>=0; i--){
static const int offset[7]= {15+0, 15+0, 15+1, 15+3, 15+6, 15+10, 15+11};
put_cabac(c, state+offset[e]+i, (a>>i)&1); //15..31
put_cabac(c, state+16+e+i, (a>>i)&1); //17..29
}
if(is_signed)
put_cabac(c, state+8 + e, v < 0); //8..14
put_cabac(c, state+9 + e, v < 0); //9..16
}
}else{
put_cabac(c, state+0, 1);
}
}
static inline int get_symbol(CABACContext *c, uint8_t *state, int is_signed){
int i;
static inline int get_symbol(CABACContext *c, uint8_t *state, int is_signed, int max_exp){
if(get_cabac(c, state+0))
return 0;
else{
const int e= get_cabac_u(c, state+1, 7, 6, 1); //1..7
if(e<7){
int i, e;
for(e=0; e<max_exp; e++){
int a= 1<<e;
for(i=e-1; i>=0; i--){
static const int offset[7]= {15+0, 15+0, 15+1, 15+3, 15+6, 15+10, 15+11};
a += get_cabac(c, state+offset[e]+i)<<i; //14..31
}
if(get_cabac(c, state + 1 + e)==0){ // 1..8
for(i=e-1; i>=0; i--){
a += get_cabac(c, state+16+e+i)<<i; //17..29
}
if(is_signed && get_cabac(c, state+8 + e)) //8..14
return -a;
else
return a;
}else
return -128;
if(is_signed && get_cabac(c, state+9 + e)) //9..16
return -a;
else
return a;
}
}
return -(1<<e);
}
}
@ -382,9 +386,9 @@ static void encode_plane(FFV1Context *s, uint8_t *src, int w, int h, int stride,
diff= (int8_t)diff;
if(s->ac)
put_symbol(c, p->state[context], diff, 1);
else{
if(s->ac){
put_symbol(c, p->state[context], diff, 1, 7);
}else{
if(context == 0) run_mode=1;
if(run_mode){
@ -434,11 +438,11 @@ static void write_quant_table(CABACContext *c, int16_t *quant_table){
for(i=1; i<128 ; i++){
if(quant_table[i] != quant_table[i-1]){
put_symbol(c, state, i-last-1, 0);
put_symbol(c, state, i-last-1, 0, 7);
last= i;
}
}
put_symbol(c, state, i-last-1, 0);
put_symbol(c, state, i-last-1, 0, 7);
}
static void write_header(FFV1Context *f){
@ -446,12 +450,12 @@ static void write_header(FFV1Context *f){
int i;
CABACContext * const c= &f->c;
put_symbol(c, state, f->version, 0);
put_symbol(c, state, f->avctx->coder_type, 0);
put_symbol(c, state, 0, 0); //YUV cs type
put_symbol(c, state, f->version, 0, 7);
put_symbol(c, state, f->avctx->coder_type, 0, 7);
put_symbol(c, state, 0, 0, 7); //YUV cs type
put_cabac(c, state, 1); //chroma planes
put_symbol(c, state, f->chroma_h_shift, 0);
put_symbol(c, state, f->chroma_v_shift, 0);
put_symbol(c, state, f->chroma_h_shift, 0, 7);
put_symbol(c, state, f->chroma_v_shift, 0, 7);
put_cabac(c, state, 0); //no transparency plane
for(i=0; i<5; i++)
@ -673,7 +677,7 @@ static void decode_plane(FFV1Context *s, uint8_t *src, int w, int h, int stride,
if(s->ac)
diff= get_symbol(c, p->state[context], 1);
diff= get_symbol(c, p->state[context], 1, 7);
else{
if(context == 0 && run_mode==0) run_mode=1;
@ -719,7 +723,7 @@ static int read_quant_table(CABACContext *c, int16_t *quant_table, int scale){
uint8_t state[CONTEXT_SIZE]={0};
for(v=0; i<128 ; v++){
int len= get_symbol(c, state, 0) + 1;
int len= get_symbol(c, state, 0, 7) + 1;
if(len + i > 128) return -1;
@ -744,18 +748,34 @@ static int read_header(FFV1Context *f){
int i, context_count;
CABACContext * const c= &f->c;
f->version= get_symbol(c, state, 0);
f->ac= f->avctx->coder_type= get_symbol(c, state, 0);
get_symbol(c, state, 0); //YUV cs type
f->version= get_symbol(c, state, 0, 7);
f->ac= f->avctx->coder_type= get_symbol(c, state, 0, 7);
get_symbol(c, state, 0, 7); //YUV cs type
get_cabac(c, state); //no chroma = false
f->chroma_h_shift= get_symbol(c, state, 0);
f->chroma_v_shift= get_symbol(c, state, 0);
f->chroma_h_shift= get_symbol(c, state, 0, 7);
f->chroma_v_shift= get_symbol(c, state, 0, 7);
get_cabac(c, state); //transparency plane
f->plane_count= 3;
switch(16*f->chroma_h_shift + f->chroma_v_shift){
case 0x00: f->avctx->pix_fmt= PIX_FMT_YUV444P; break;
case 0x10: f->avctx->pix_fmt= PIX_FMT_YUV422P; break;
case 0x11: f->avctx->pix_fmt= PIX_FMT_YUV420P; break;
case 0x20: f->avctx->pix_fmt= PIX_FMT_YUV411P; break;
case 0x33: f->avctx->pix_fmt= PIX_FMT_YUV410P; break;
default:
fprintf(stderr, "format not supported\n");
return -1;
}
//printf("%d %d %d\n", f->chroma_h_shift, f->chroma_v_shift,f->avctx->pix_fmt);
context_count=1;
for(i=0; i<5; i++){
context_count*= read_quant_table(c, f->quant_table[i], context_count);
if(context_count < 0){
printf("read_quant_table error\n");
return -1;
}
}
context_count= (context_count+1)/2;
@ -823,12 +843,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
ff_init_cabac_decoder(c, buf, buf_size);
ff_init_cabac_states(c, ff_h264_lps_range, ff_h264_mps_state, ff_h264_lps_state, 64);
p->reference= 0;
if(avctx->get_buffer(avctx, p) < 0){
fprintf(stderr, "get_buffer() failed\n");
return -1;
}
p->pict_type= FF_I_TYPE; //FIXME I vs. P
if(get_cabac_bypass(c)){
p->key_frame= 1;
@ -837,8 +851,15 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
}else{
p->key_frame= 0;
}
p->reference= 0;
if(avctx->get_buffer(avctx, p) < 0){
fprintf(stderr, "get_buffer() failed\n");
return -1;
}
if(avctx->debug&FF_DEBUG_PICT_INFO)
printf("keyframe:%d\n", p->key_frame);
printf("keyframe:%d coder:%d\n", p->key_frame, f->ac);
if(!f->ac){
bytes_read = get_cabac_terminate(c);