[FFmpeg-cvslog] mss12: reduce SliceContext size from 1067 to 164 KB
Alberto Delmás
git at videolan.org
Tue Sep 4 17:15:01 CEST 2012
ffmpeg | branch: master | Alberto Delmás <adelmas at gmail.com> | Sun Sep 2 12:44:21 2012 +0200| [626c1a33ed43c943b142f3357aaf369239cfe54a] | committer: Kostya Shishkov
mss12: reduce SliceContext size from 1067 to 164 KB
Signed-off-by: Kostya Shishkov <kostya.shishkov at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=626c1a33ed43c943b142f3357aaf369239cfe54a
---
libavcodec/mss1.c | 2 +-
libavcodec/mss12.c | 54 +++++++++++++++++++++++-----------------------------
libavcodec/mss12.h | 9 ++++-----
libavcodec/mss2.c | 2 +-
4 files changed, 30 insertions(+), 37 deletions(-)
diff --git a/libavcodec/mss1.c b/libavcodec/mss1.c
index 678208b..1591bba 100644
--- a/libavcodec/mss1.c
+++ b/libavcodec/mss1.c
@@ -89,7 +89,7 @@ static int arith_get_number(ArithCoder *c, int mod_val)
return val;
}
-static int arith_get_prob(ArithCoder *c, int *probs)
+static int arith_get_prob(ArithCoder *c, int16_t *probs)
{
int range = c->high - c->low + 1;
int val = ((c->value - c->low + 1) * probs[0] - 1) / range;
diff --git a/libavcodec/mss12.c b/libavcodec/mss12.c
index ea12769..1059f66 100644
--- a/libavcodec/mss12.c
+++ b/libavcodec/mss12.c
@@ -61,13 +61,9 @@ static void model_reset(Model *m)
m->weights[i] = 1;
m->cum_prob[i] = m->num_syms - i;
}
- m->weights[0] = -1;
- m->idx2sym[0] = -1;
- m->sym2idx[m->num_syms] = -1;
- for (i = 0; i < m->num_syms; i++) {
- m->sym2idx[i] = i + 1;
+ m->weights[0] = 0;
+ for (i = 0; i < m->num_syms; i++)
m->idx2sym[i + 1] = i;
- }
}
static av_cold void model_init(Model *m, int num_syms, int thr_weight)
@@ -75,7 +71,6 @@ static av_cold void model_init(Model *m, int num_syms, int thr_weight)
m->num_syms = num_syms;
m->thr_weight = thr_weight;
m->threshold = num_syms * thr_weight;
- model_reset(m);
}
static void model_rescale_weights(Model *m)
@@ -109,8 +104,6 @@ void ff_mss12_model_update(Model *m, int val)
m->idx2sym[val] = sym2;
m->idx2sym[i] = sym1;
- m->sym2idx[sym1] = i;
- m->sym2idx[sym2] = val;
val = i;
}
@@ -123,7 +116,7 @@ void ff_mss12_model_update(Model *m, int val)
static void pixctx_reset(PixContext *ctx)
{
- int i, j, k;
+ int i, j;
if (!ctx->special_initial_cache)
for (i = 0; i < ctx->cache_size; i++)
@@ -137,16 +130,15 @@ static void pixctx_reset(PixContext *ctx)
model_reset(&ctx->cache_model);
model_reset(&ctx->full_model);
- for (i = 0; i < 4; i++)
- for (j = 0; j < sec_order_sizes[i]; j++)
- for (k = 0; k < 4; k++)
- model_reset(&ctx->sec_models[i][j][k]);
+ for (i = 0; i < 15; i++)
+ for (j = 0; j < 4; j++)
+ model_reset(&ctx->sec_models[i][j]);
}
static av_cold void pixctx_init(PixContext *ctx, int cache_size,
int full_model_syms, int special_initial_cache)
{
- int i, j, k;
+ int i, j, k, idx;
ctx->cache_size = cache_size + 4;
ctx->num_syms = cache_size;
@@ -155,10 +147,10 @@ static av_cold void pixctx_init(PixContext *ctx, int cache_size,
model_init(&ctx->cache_model, ctx->num_syms + 1, THRESH_LOW);
model_init(&ctx->full_model, full_model_syms, THRESH_HIGH);
- for (i = 0; i < 4; i++)
- for (j = 0; j < sec_order_sizes[i]; j++)
+ for (i = 0, idx = 0; i < 4; i++)
+ for (j = 0; j < sec_order_sizes[i]; j++, idx++)
for (k = 0; k < 4; k++)
- model_init(&ctx->sec_models[i][j][k], 2 + i,
+ model_init(&ctx->sec_models[idx][k], 2 + i,
i ? THRESH_LOW : THRESH_ADAPTIVE);
}
@@ -268,46 +260,48 @@ static int decode_pixel_in_context(ArithCoder *acoder, PixContext *pctx,
switch (nlen) {
case 1:
- case 4:
layer = 0;
break;
case 2:
if (neighbours[TOP] == neighbours[TOP_LEFT]) {
if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
- layer = 3;
+ layer = 1;
else if (neighbours[LEFT] == neighbours[TOP_LEFT])
layer = 2;
else
- layer = 4;
+ layer = 3;
} else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) {
if (neighbours[LEFT] == neighbours[TOP_LEFT])
- layer = 1;
+ layer = 4;
else
layer = 5;
} else if (neighbours[LEFT] == neighbours[TOP_LEFT]) {
layer = 6;
} else {
- layer = 0;
+ layer = 7;
}
break;
case 3:
if (neighbours[TOP] == neighbours[TOP_LEFT])
- layer = 0;
+ layer = 8;
else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
- layer = 1;
+ layer = 9;
else if (neighbours[LEFT] == neighbours[TOP_LEFT])
- layer = 2;
+ layer = 10;
else if (neighbours[TOP_RIGHT] == neighbours[TOP])
- layer = 3;
+ layer = 11;
else if (neighbours[TOP] == neighbours[LEFT])
- layer = 4;
+ layer = 12;
else
- layer = 5;
+ layer = 13;
+ break;
+ case 4:
+ layer = 14;
break;
}
pix = acoder->get_model_sym(acoder,
- &pctx->sec_models[nlen - 1][layer][sub]);
+ &pctx->sec_models[layer][sub]);
if (pix < nlen)
return ref_pix[pix];
else
diff --git a/libavcodec/mss12.h b/libavcodec/mss12.h
index 97cd25f..678a0c0 100644
--- a/libavcodec/mss12.h
+++ b/libavcodec/mss12.h
@@ -38,10 +38,9 @@
#define THRESH_HIGH 50
typedef struct Model {
- int cum_prob[MODEL_MAX_SYMS + 1];
- int weights[MODEL_MAX_SYMS + 1];
- int idx2sym[MODEL_MAX_SYMS + 1];
- int sym2idx[MODEL_MAX_SYMS + 1];
+ int16_t cum_prob[MODEL_MAX_SYMS + 1];
+ int16_t weights[MODEL_MAX_SYMS + 1];
+ uint8_t idx2sym[MODEL_MAX_SYMS + 1];
int num_syms;
int thr_weight, threshold;
} Model;
@@ -60,7 +59,7 @@ typedef struct PixContext {
int cache_size, num_syms;
uint8_t cache[12];
Model cache_model, full_model;
- Model sec_models[4][8][4];
+ Model sec_models[15][4];
int special_initial_cache;
} PixContext;
diff --git a/libavcodec/mss2.c b/libavcodec/mss2.c
index e4c854a..ce3cfb8 100644
--- a/libavcodec/mss2.c
+++ b/libavcodec/mss2.c
@@ -106,7 +106,7 @@ static int arith2_get_number(ArithCoder *c, int n)
return val;
}
-static int arith2_get_prob(ArithCoder *c, int *probs)
+static int arith2_get_prob(ArithCoder *c, int16_t *probs)
{
int range = c->high - c->low + 1, n = *probs;
int scale = av_log2(range) - av_log2(n);
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