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rebalance method tools (-m) for methods [0..4]

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(methods 5 and 6 are still untouched).

Methods #0 and #1 got much faster
Method #2 gets vastly improved in quality
Method #3 is noticeably faster for little lower quality
Method #4 (default) is 10-20% faster for comparable quality

+ update the internal doc about the methods' tools.

Example of speed difference:

Time to encode picture:
Method | Before | After
-m 0   | 1.272s | 0.517s
-m 1   | 1.295s | 0.623s
-m 2   | 2.217s | 0.834s
-m 3   | 2.816s | 2.243s
-m 4   | 3.235s | 3.014s
-m 5   | 3.668s | 3.654s
-m 6   | 8.296s | 8.235s

Change-Id: Ic41fda5de65066b3a6586cb8ae1ebb0206d47fe0
This commit is contained in:
Pascal Massimino
2013-02-26 05:22:44 -08:00
parent 5189957e07
commit 58ca6f65b7
5 changed files with 111 additions and 34 deletions
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13
src/enc/frame.c
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@ -811,9 +811,10 @@ static int OneStatPass(VP8Encoder* const enc, float q, VP8RDLevel rd_opt,
static const int dqs[] = { 20, 15, 10, 8, 6, 4, 2, 1, 0 };
int VP8StatLoop(VP8Encoder* const enc) {
const int method = enc->method_;
const int do_search =
(enc->config_->target_size > 0 || enc->config_->target_PSNR > 0);
const int fast_probe = (enc->method_ < 2 && !do_search);
const int fast_probe = ((method == 0 || method == 3) && !do_search);
float q = enc->config_->quality;
const int max_passes = enc->config_->pass;
const int task_percent = 20;
@ -824,12 +825,18 @@ int VP8StatLoop(VP8Encoder* const enc) {
// Fast mode: quick analysis pass over few mbs. Better than nothing.
nb_mbs = enc->mb_w_ * enc->mb_h_;
if (fast_probe && nb_mbs > 100) nb_mbs = 100;
if (fast_probe) {
if (method == 3) { // we need more stats for method 3 to be reliable.
nb_mbs = (nb_mbs > 200) ? nb_mbs >> 1 : 100;
} else {
nb_mbs = (nb_mbs > 200) ? nb_mbs >> 2 : 50;
}
}
// No target size: just do several pass without changing 'q'
if (!do_search) {
for (pass = 0; pass < max_passes; ++pass) {
const VP8RDLevel rd_opt = (enc->method_ > 2) ? RD_OPT_BASIC : RD_OPT_NONE;
const VP8RDLevel rd_opt = (method >= 3) ? RD_OPT_BASIC : RD_OPT_NONE;
if (!OneStatPass(enc, q, rd_opt, nb_mbs, NULL, percent_per_pass)) {
return 0;
}