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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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22
src/enc/analysis.c
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@ -223,14 +223,18 @@ static void AssignSegments(VP8Encoder* const enc,
// susceptibility and set best modes for this macroblock.
// Segment assignment is done later.
// Number of modes to inspect for alpha_ evaluation. For high-quality settings,
// we don't need to test all the possible modes during the analysis phase.
// Number of modes to inspect for alpha_ evaluation. For high-quality settings
// (method >= FAST_ANALYSIS_METHOD) we don't need to test all the possible modes
// during the analysis phase.
#define FAST_ANALYSIS_METHOD 4 // method above which we do partial analysis
#define MAX_INTRA16_MODE 2
#define MAX_INTRA4_MODE 2
#define MAX_UV_MODE 2
static int MBAnalyzeBestIntra16Mode(VP8EncIterator* const it) {
const int max_mode = (it->enc_->method_ >= 3) ? MAX_INTRA16_MODE : 4;
const int max_mode =
(it->enc_->method_ >= FAST_ANALYSIS_METHOD) ? MAX_INTRA16_MODE
: NUM_PRED_MODES;
int mode;
int best_alpha = DEFAULT_ALPHA;
int best_mode = 0;
@ -256,7 +260,9 @@ static int MBAnalyzeBestIntra16Mode(VP8EncIterator* const it) {
static int MBAnalyzeBestIntra4Mode(VP8EncIterator* const it,
int best_alpha) {
uint8_t modes[16];
const int max_mode = (it->enc_->method_ >= 3) ? MAX_INTRA4_MODE : NUM_BMODES;
const int max_mode =
(it->enc_->method_ >= FAST_ANALYSIS_METHOD) ? MAX_INTRA4_MODE
: NUM_BMODES;
int i4_alpha;
VP8Histogram total_histo = { { 0 } };
int cur_histo = 0;
@ -298,7 +304,9 @@ static int MBAnalyzeBestIntra4Mode(VP8EncIterator* const it,
static int MBAnalyzeBestUVMode(VP8EncIterator* const it) {
int best_alpha = DEFAULT_ALPHA;
int best_mode = 0;
const int max_mode = (it->enc_->method_ >= 3) ? MAX_UV_MODE : 4;
const int max_mode =
(it->enc_->method_ >= FAST_ANALYSIS_METHOD) ? MAX_UV_MODE
: NUM_PRED_MODES;
int mode;
VP8MakeChroma8Preds(it);
for (mode = 0; mode < max_mode; ++mode) {
@ -328,7 +336,7 @@ static void MBAnalyze(VP8EncIterator* const it,
VP8SetSegment(it, 0); // default segment, spec-wise.
best_alpha = MBAnalyzeBestIntra16Mode(it);
if (enc->method_ != 3) {
if (enc->method_ >= 5) {
// We go and make a fast decision for intra4/intra16.
// It's usually not a good and definitive pick, but helps seeding the stats
// about level bit-cost.
@ -383,7 +391,7 @@ int VP8EncAnalyze(VP8Encoder* const enc) {
const int do_segments =
enc->config_->emulate_jpeg_size || // We need the complexity evaluation.
(enc->segment_hdr_.num_segments_ > 1) ||
(enc->method_ <= 2); // for methods 0,1,2, we need preds_[] to be filled.
(enc->method_ == 0); // for method 0, we need preds_[] to be filled.
enc->alpha_ = 0;
enc->uv_alpha_ = 0;
if (do_segments) {