This increases the search space from the hardcoded 17 tables
to ~ 23^512 tables
The mul_count choice is chosen by bruteforce
All testcases tried, improve
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc>
---
libavcodec/ffv1enc.c | 89 +++++++++++++++++++++++++-------------------
1 file changed, 51 insertions(+), 38 deletions(-)
diff --git a/libavcodec/ffv1enc.c b/libavcodec/ffv1enc.c
index bc59f96746c..5e7c714035e 100644
--- a/libavcodec/ffv1enc.c
+++ b/libavcodec/ffv1enc.c
@@ -1409,52 +1409,65 @@ static void encode_float32_remap(FFV1Context *f,
FFV1SliceContext *sc,
av_assert0 (s.pixel_num <= 65536);
for (int p= 0; p < 1 + 2*f->chroma_planes + f->transparency; p++) {
- float score_tab[16] = {0};
- int64_t last_val = -1;
- int best_index = 0;
+ float score_sum[2] = {0};
+ int mul_all[2][513];
s.rc = sc->c;
s.i = 0;
s.p = p;
- for(int v = 0; v< 512; v++) {
- if (v >= 0x378/8 && v <= 23 + 0x378/8) {
- s.mul[v] = -(0x800080 >> (v - 0x378/8));
- } else
- s.mul[v] = -1;
- }
- for (int i= 0; i<s.pixel_num; i++) {
- int64_t val = sc->unit[p][i].val;
- if (val != last_val) {
- av_assert2(last_val < val);
- for(int si= 0; si < FF_ARRAY_ELEMS(score_tab); si++) {
- int64_t delta = val - last_val;
- int mul;
- int64_t cost;
-
- if (last_val < 0) {
- mul = 1;
- } else if (si + 1 == FF_ARRAY_ELEMS(score_tab)) {
- mul = -s.mul[ (last_val + 1) >> (32-9) ];
- } else
- mul = 1<<si;
-
- cost = FFMAX((delta + mul/2) / mul, 1);
- score_tab[si] += log2(cost) + log2(fabs(delta -
cost*mul)+1);
+ for (int mul_count= 1; mul_count<=512; mul_count+=511) {
+ float score_tab_all[513][23] = {0};
+ int64_t last_val = -1;
+ int *mul_tab = mul_all[mul_count>>9];
+ int last_mul_index = -1;
+ score_sum[mul_count>>9] += log2(mul_count);
+ for (int i= 0; i<s.pixel_num; i++) {
+ int64_t val = sc->unit[p][i].val;
+ int mul_index = (val + 1LL)*mul_count >> 32;
+ if (val != last_val) {
+ float *score_tab = score_tab_all[(last_val +
1LL)*mul_count >> 32];
+ av_assert2(last_val < val);
+ for(int si= 0; si < FF_ARRAY_ELEMS(*score_tab_all); si++) {
+ int64_t delta = val - last_val;
+ int mul;
+ int64_t cost;
+
+ if (last_val < 0) {
+ mul = 1;
+ } else {
+ mul = (0x10001LL)<<si >> 16;
+ }
+
+ cost = FFMAX((delta + mul/2) / mul, 1);
+ score_tab[si] += log2(cost);
+ if (mul > 1)
+ score_tab[si] += log2(fabs(delta - cost*mul)+1) *
(1 + (mul_count > 1));
+ if (mul_index != last_mul_index)
+ score_tab[si] += 0.5*log2(mul);
+ }
}
last_val = val;
+ last_mul_index = mul_index;
}
+ for(int i= 0; i<mul_count; i++) {
+ int best_index = 0;
+ float *score_tab = score_tab_all[i];
+ for(int si= 1; si < FF_ARRAY_ELEMS(*score_tab_all); si++) {
+ if (score_tab[si] < score_tab[ best_index ])
+ best_index = si;
+ }
+ mul_tab[i] = -((0x10001LL)<<best_index >> 16);
+ score_sum[mul_count>>9] += score_tab[ best_index ];
+ }
+ mul_tab[mul_count] = 1;
+
+ s.mul_count = mul_count;
+ memcpy(s.mul, mul_all[s.mul_count>>9],
sizeof(*s.mul)*(s.mul_count+1));
+ score_sum[mul_count>>9] = encode_float32_remap_segment(sc, &s, 0,
0);
}
- for(int si= 1; si < FF_ARRAY_ELEMS(score_tab); si++) {
- if (score_tab[si] < score_tab[ best_index ])
- best_index = si;
- }
- if (best_index + 1 < FF_ARRAY_ELEMS(score_tab)) {
- s.mul[0] = -1 << best_index;
- s.mul_count = 1;
- } else {
- s.mul_count = 512;
- }
- s.mul[s.mul_count] = 1;
+
+ s.mul_count = score_sum[0] <= score_sum[1] ? 1 : 512;
+ memcpy(s.mul, mul_all[s.mul_count>>9], sizeof(*s.mul)*(s.mul_count+1));
encode_float32_remap_segment(sc, &s, 1, 1);
--
2.48.1
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