Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

j2k[c/h] j2kdec.c: Implement 2 code block styles

Browse Source
pull/2/head
Rukhsana Ruby 14 years ago committed by Michael Niedermayer
parent cbe60f3451
commit 88e9397ef1
3 changed files with 33 additions and 15 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 16
      libavcodec/j2k.c
  2. 2
      libavcodec/j2k.h
  3. 30
      libavcodec/j2kdec.c

16
libavcodec/j2k.c
Unescape View File

@ -105,18 +105,20 @@ static void tag_tree_zero(J2kTgtNode *t, int w, int h)
uint8_t ff_j2k_nbctxno_lut[256][4];
static int getnbctxno(int flag, int bandno)
static int getnbctxno(int flag, int bandno, int vert_causal_ctx_csty_symbol)
{
int h, v, d;
h = ((flag & J2K_T1_SIG_E) ? 1:0)+
((flag & J2K_T1_SIG_W) ? 1:0);
v = ((flag & J2K_T1_SIG_N) ? 1:0)+
((flag & J2K_T1_SIG_S) ? 1:0);
v = ((flag & J2K_T1_SIG_N) ? 1:0);
if (!vert_causal_ctx_csty_symbol)
v = v + ((flag & J2K_T1_SIG_S) ? 1:0);
d = ((flag & J2K_T1_SIG_NE) ? 1:0)+
((flag & J2K_T1_SIG_NW) ? 1:0)+
((flag & J2K_T1_SIG_SE) ? 1:0)+
((flag & J2K_T1_SIG_SW) ? 1:0);
((flag & J2K_T1_SIG_NW) ? 1:0);
if (!vert_causal_ctx_csty_symbol)
d = d + ((flag & J2K_T1_SIG_SE) ? 1:0)+
((flag & J2K_T1_SIG_SW) ? 1:0);
if (bandno < 3){
if (bandno == 1)
FFSWAP(int, h, v);
@ -171,7 +173,7 @@ void ff_j2k_init_tier1_luts(void)
int i, j;
for (i = 0; i < 256; i++)
for (j = 0; j < 4; j++)
ff_j2k_nbctxno_lut[i][j] = getnbctxno(i, j);
ff_j2k_nbctxno_lut[i][j] = getnbctxno(i, j, 0);
for (i = 0; i < 16; i++)
for (j = 0; j < 16; j++)
ff_j2k_sgnctxno_lut[i][j] = getsgnctxno(i + (j << 8), &ff_j2k_xorbit_lut[i][j]);

2
libavcodec/j2k.h
Unescape View File

@ -208,7 +208,7 @@ void ff_j2k_set_significant(J2kT1Context *t1, int x, int y, int negative);
extern uint8_t ff_j2k_nbctxno_lut[256][4];
static inline int ff_j2k_getnbctxno(int flag, int bandno)
static inline int ff_j2k_getnbctxno(int flag, int bandno, int vert_causal_ctx_csty_symbol)
{
return ff_j2k_nbctxno_lut[flag&255][bandno];
}

30
libavcodec/j2kdec.c
Unescape View File

@ -592,7 +592,8 @@ static int decode_packets(J2kDecoderContext *s, J2kTile *tile)
}
/* TIER-1 routines */
static void decode_sigpass(J2kT1Context *t1, int width, int height, int bpno, int bandno)
static void decode_sigpass(J2kT1Context *t1, int width, int height, int bpno, int bandno, int bpass_csty_symbol,
int vert_causal_ctx_csty_symbol)
{
int mask = 3 << (bpno - 1), y0, x, y;
@ -601,10 +602,15 @@ static void decode_sigpass(J2kT1Context *t1, int width, int height, int bpno, in
for (y = y0; y < height && y < y0+4; y++){
if ((t1->flags[y+1][x+1] & J2K_T1_SIG_NB)
&& !(t1->flags[y+1][x+1] & (J2K_T1_SIG | J2K_T1_VIS))){
if (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ff_j2k_getnbctxno(t1->flags[y+1][x+1], bandno))){
int vert_causal_ctx_csty_loc_symbol = vert_causal_ctx_csty_symbol && (x == 3 && y == 3);
if (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ff_j2k_getnbctxno(t1->flags[y+1][x+1], bandno,
vert_causal_ctx_csty_loc_symbol))){
int xorbit, ctxno = ff_j2k_getsgnctxno(t1->flags[y+1][x+1], &xorbit);
t1->data[y][x] = (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ^ xorbit) ? -mask : mask;
if (bpass_csty_symbol)
t1->data[y][x] = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ? -mask : mask;
else
t1->data[y][x] = (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ^ xorbit) ?
-mask : mask;
ff_j2k_set_significant(t1, x, y, t1->data[y][x] < 0);
}
@ -658,7 +664,8 @@ static void decode_clnpass(J2kDecoderContext *s, J2kT1Context *t1, int width, in
for (y = y0 + runlen; y < y0 + 4 && y < height; y++){
if (!dec){
if (!(t1->flags[y+1][x+1] & (J2K_T1_SIG | J2K_T1_VIS)))
dec = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ff_j2k_getnbctxno(t1->flags[y+1][x+1], bandno));
dec = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ff_j2k_getnbctxno(t1->flags[y+1][x+1],
bandno, 0));
}
if (dec){
int xorbit, ctxno = ff_j2k_getsgnctxno(t1->flags[y+1][x+1], &xorbit);
@ -685,7 +692,7 @@ static void decode_clnpass(J2kDecoderContext *s, J2kT1Context *t1, int width, in
static int decode_cblk(J2kDecoderContext *s, J2kCodingStyle *codsty, J2kT1Context *t1, J2kCblk *cblk,
int width, int height, int bandpos)
{
int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1, y;
int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1, y, clnpass_cnt = 0;
for (y = 0; y < height+2; y++)
memset(t1->flags[y], 0, (width+2)*sizeof(int));
@ -697,14 +704,23 @@ static int decode_cblk(J2kDecoderContext *s, J2kCodingStyle *codsty, J2kT1Contex
cblk->data[cblk->length] = 0xff;
cblk->data[cblk->length+1] = 0xff;
int bpass_csty_symbol = J2K_CBLK_BYPASS & codsty->cblk_style;
int vert_causal_ctx_csty_symbol = J2K_CBLK_VSC & codsty->cblk_style;
while(passno--){
switch(pass_t){
case 0: decode_sigpass(t1, width, height, bpno+1, bandpos);
case 0: decode_sigpass(t1, width, height, bpno+1, bandpos,
bpass_csty_symbol && (clnpass_cnt >= 4), vert_causal_ctx_csty_symbol);
break;
case 1: decode_refpass(t1, width, height, bpno+1);
if (bpass_csty_symbol && clnpass_cnt >= 4)
ff_mqc_initdec(&t1->mqc, cblk->data);
break;
case 2: decode_clnpass(s, t1, width, height, bpno+1, bandpos,
codsty->cblk_style & J2K_CBLK_SEGSYM);
clnpass_cnt = clnpass_cnt + 1;
if (bpass_csty_symbol && clnpass_cnt >= 4)
ff_mqc_initdec(&t1->mqc, cblk->data);
break;
}

Write Preview
Loading…
Cancel
Save