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authorDiego Biurrun <diego@biurrun.de>2011-07-07 23:16:56 +0200
committerDiego Biurrun <diego@biurrun.de>2011-07-17 12:56:42 +0200
commitfd065d3e799033ed0159f766067f3deefecaf48a (patch)
tree2f7e209b612cec175425ec7c7b9a9191faff1cf5 /libavcodec/cabac.c
parent0a858048af695e0d5788f0613fc2dc490572e1de (diff)
downloadffmpeg-fd065d3e799033ed0159f766067f3deefecaf48a.tar.gz
cabac: Move code only used in the cabac test program to cabac.c.
Diffstat (limited to 'libavcodec/cabac.c')
-rw-r--r--libavcodec/cabac.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/libavcodec/cabac.c b/libavcodec/cabac.c
index 4846b32e87..57ab395ed7 100644
--- a/libavcodec/cabac.c
+++ b/libavcodec/cabac.c
@@ -166,6 +166,140 @@ void ff_init_cabac_states(CABACContext *c){
#include "avcodec.h"
#include "cabac.h"
+static void put_cabac(CABACContext *c, uint8_t * const state, int bit){
+ int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + *state];
+
+ if(bit == ((*state)&1)){
+ c->range -= RangeLPS;
+ *state= ff_h264_mps_state[*state];
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ *state= ff_h264_lps_state[*state];
+ }
+
+ renorm_cabac_encoder(c);
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+/**
+ * @param bit 0 -> write zero bit, !=0 write one bit
+ */
+static void put_cabac_bypass(CABACContext *c, int bit){
+ c->low += c->low;
+
+ if(bit){
+ c->low += c->range;
+ }
+//FIXME optimize
+ if(c->low<0x200){
+ put_cabac_bit(c, 0);
+ }else if(c->low<0x400){
+ c->outstanding_count++;
+ c->low -= 0x200;
+ }else{
+ put_cabac_bit(c, 1);
+ c->low -= 0x400;
+ }
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+/**
+ *
+ * @return the number of bytes written
+ */
+static int put_cabac_terminate(CABACContext *c, int bit){
+ c->range -= 2;
+
+ if(!bit){
+ renorm_cabac_encoder(c);
+ }else{
+ c->low += c->range;
+ c->range= 2;
+
+ renorm_cabac_encoder(c);
+
+ assert(c->low <= 0x1FF);
+ put_cabac_bit(c, c->low>>9);
+ put_bits(&c->pb, 2, ((c->low>>7)&3)|1);
+
+ flush_put_bits(&c->pb); //FIXME FIXME FIXME XXX wrong
+ }
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+
+ return (put_bits_count(&c->pb)+7)>>3;
+}
+
+/**
+ * put (truncated) unary binarization.
+ */
+static void put_cabac_u(CABACContext *c, uint8_t * state, int v, int max, int max_index, int truncated){
+ int i;
+
+ assert(v <= max);
+
+ for(i=0; i<v; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+ if(truncated==0 || v<max)
+ put_cabac(c, state, 0);
+}
+
+/**
+ * put unary exp golomb k-th order binarization.
+ */
+static void put_cabac_ueg(CABACContext *c, uint8_t * state, int v, int max, int is_signed, int k, int max_index){
+ int i;
+
+ if(v==0)
+ put_cabac(c, state, 0);
+ else{
+ const int sign= v < 0;
+
+ if(is_signed) v= FFABS(v);
+
+ if(v<max){
+ for(i=0; i<v; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+
+ put_cabac(c, state, 0);
+ }else{
+ int m= 1<<k;
+
+ for(i=0; i<max; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+
+ v -= max;
+ while(v >= m){ //FIXME optimize
+ put_cabac_bypass(c, 1);
+ v-= m;
+ m+= m;
+ }
+ put_cabac_bypass(c, 0);
+ while(m>>=1){
+ put_cabac_bypass(c, v&m);
+ }
+ }
+
+ if(is_signed)
+ put_cabac_bypass(c, sign);
+ }
+}
+
int main(void){
CABACContext c;
uint8_t b[9*SIZE];