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-rw-r--r--drivers/webp/enc/analysis.c347
1 files changed, 107 insertions, 240 deletions
diff --git a/drivers/webp/enc/analysis.c b/drivers/webp/enc/analysis.c
index 7d4cfdc190..22cfb492e7 100644
--- a/drivers/webp/enc/analysis.c
+++ b/drivers/webp/enc/analysis.c
@@ -1,10 +1,8 @@
// Copyright 2011 Google Inc. All Rights Reserved.
//
-// Use of this source code is governed by a BSD-style license
-// that can be found in the COPYING file in the root of the source
-// tree. An additional intellectual property rights grant can be found
-// in the file PATENTS. All contributing project authors may
-// be found in the AUTHORS file in the root of the source tree.
+// This code is licensed under the same terms as WebM:
+// Software License Agreement: http://www.webmproject.org/license/software/
+// Additional IP Rights Grant: http://www.webmproject.org/license/additional/
// -----------------------------------------------------------------------------
//
// Macroblock analysis
@@ -19,8 +17,16 @@
#include "./cost.h"
#include "../utils/utils.h"
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
#define MAX_ITERS_K_MEANS 6
+static int ClipAlpha(int alpha) {
+ return alpha < 0 ? 0 : alpha > 255 ? 255 : alpha;
+}
+
//------------------------------------------------------------------------------
// Smooth the segment map by replacing isolated block by the majority of its
// neighbours.
@@ -51,7 +57,6 @@ static void SmoothSegmentMap(VP8Encoder* const enc) {
for (n = 0; n < NUM_MB_SEGMENTS; ++n) {
if (cnt[n] >= majority_cnt_3_x_3_grid) {
majority_seg = n;
- break;
}
}
tmp[x + y * w] = majority_seg;
@@ -67,10 +72,50 @@ static void SmoothSegmentMap(VP8Encoder* const enc) {
}
//------------------------------------------------------------------------------
-// set segment susceptibility alpha_ / beta_
+// Finalize Segment probability based on the coding tree
+
+static int GetProba(int a, int b) {
+ int proba;
+ const int total = a + b;
+ if (total == 0) return 255; // that's the default probability.
+ proba = (255 * a + total / 2) / total;
+ return proba;
+}
+
+static void SetSegmentProbas(VP8Encoder* const enc) {
+ int p[NUM_MB_SEGMENTS] = { 0 };
+ int n;
+
+ for (n = 0; n < enc->mb_w_ * enc->mb_h_; ++n) {
+ const VP8MBInfo* const mb = &enc->mb_info_[n];
+ p[mb->segment_]++;
+ }
+ if (enc->pic_->stats) {
+ for (n = 0; n < NUM_MB_SEGMENTS; ++n) {
+ enc->pic_->stats->segment_size[n] = p[n];
+ }
+ }
+ if (enc->segment_hdr_.num_segments_ > 1) {
+ uint8_t* const probas = enc->proba_.segments_;
+ probas[0] = GetProba(p[0] + p[1], p[2] + p[3]);
+ probas[1] = GetProba(p[0], p[1]);
+ probas[2] = GetProba(p[2], p[3]);
+
+ enc->segment_hdr_.update_map_ =
+ (probas[0] != 255) || (probas[1] != 255) || (probas[2] != 255);
+ enc->segment_hdr_.size_ =
+ p[0] * (VP8BitCost(0, probas[0]) + VP8BitCost(0, probas[1])) +
+ p[1] * (VP8BitCost(0, probas[0]) + VP8BitCost(1, probas[1])) +
+ p[2] * (VP8BitCost(1, probas[0]) + VP8BitCost(0, probas[2])) +
+ p[3] * (VP8BitCost(1, probas[0]) + VP8BitCost(1, probas[2]));
+ } else {
+ enc->segment_hdr_.update_map_ = 0;
+ enc->segment_hdr_.size_ = 0;
+ }
+}
static WEBP_INLINE int clip(int v, int m, int M) {
- return (v < m) ? m : (v > M) ? M : v;
+ return v < m ? m : v > M ? M : v;
}
static void SetSegmentAlphas(VP8Encoder* const enc,
@@ -97,72 +142,28 @@ static void SetSegmentAlphas(VP8Encoder* const enc,
}
//------------------------------------------------------------------------------
-// Compute susceptibility based on DCT-coeff histograms:
-// the higher, the "easier" the macroblock is to compress.
-
-#define MAX_ALPHA 255 // 8b of precision for susceptibilities.
-#define ALPHA_SCALE (2 * MAX_ALPHA) // scaling factor for alpha.
-#define DEFAULT_ALPHA (-1)
-#define IS_BETTER_ALPHA(alpha, best_alpha) ((alpha) > (best_alpha))
-
-static int FinalAlphaValue(int alpha) {
- alpha = MAX_ALPHA - alpha;
- return clip(alpha, 0, MAX_ALPHA);
-}
-
-static int GetAlpha(const VP8Histogram* const histo) {
- int max_value = 0, last_non_zero = 1;
- int k;
- int alpha;
- for (k = 0; k <= MAX_COEFF_THRESH; ++k) {
- const int value = histo->distribution[k];
- if (value > 0) {
- if (value > max_value) max_value = value;
- last_non_zero = k;
- }
- }
- // 'alpha' will later be clipped to [0..MAX_ALPHA] range, clamping outer
- // values which happen to be mostly noise. This leaves the maximum precision
- // for handling the useful small values which contribute most.
- alpha = (max_value > 1) ? ALPHA_SCALE * last_non_zero / max_value : 0;
- return alpha;
-}
-
-static void MergeHistograms(const VP8Histogram* const in,
- VP8Histogram* const out) {
- int i;
- for (i = 0; i <= MAX_COEFF_THRESH; ++i) {
- out->distribution[i] += in->distribution[i];
- }
-}
-
-//------------------------------------------------------------------------------
// Simplified k-Means, to assign Nb segments based on alpha-histogram
-static void AssignSegments(VP8Encoder* const enc,
- const int alphas[MAX_ALPHA + 1]) {
+static void AssignSegments(VP8Encoder* const enc, const int alphas[256]) {
const int nb = enc->segment_hdr_.num_segments_;
int centers[NUM_MB_SEGMENTS];
int weighted_average = 0;
- int map[MAX_ALPHA + 1];
+ int map[256];
int a, n, k;
- int min_a = 0, max_a = MAX_ALPHA, range_a;
+ int min_a = 0, max_a = 255, range_a;
// 'int' type is ok for histo, and won't overflow
int accum[NUM_MB_SEGMENTS], dist_accum[NUM_MB_SEGMENTS];
- assert(nb >= 1);
-
// bracket the input
- for (n = 0; n <= MAX_ALPHA && alphas[n] == 0; ++n) {}
+ for (n = 0; n < 256 && alphas[n] == 0; ++n) {}
min_a = n;
- for (n = MAX_ALPHA; n > min_a && alphas[n] == 0; --n) {}
+ for (n = 255; n > min_a && alphas[n] == 0; --n) {}
max_a = n;
range_a = max_a - min_a;
// Spread initial centers evenly
- for (k = 0, n = 1; k < nb; ++k, n += 2) {
- assert(n < 2 * nb);
- centers[k] = min_a + (n * range_a) / (2 * nb);
+ for (n = 1, k = 0; n < 2 * nb; n += 2) {
+ centers[k++] = min_a + (n * range_a) / (2 * nb);
}
for (k = 0; k < MAX_ITERS_K_MEANS; ++k) { // few iters are enough
@@ -177,7 +178,7 @@ static void AssignSegments(VP8Encoder* const enc,
n = 0; // track the nearest center for current 'a'
for (a = min_a; a <= max_a; ++a) {
if (alphas[a]) {
- while (n + 1 < nb && abs(a - centers[n + 1]) < abs(a - centers[n])) {
+ while (n < nb - 1 && abs(a - centers[n + 1]) < abs(a - centers[n])) {
n++;
}
map[a] = n;
@@ -209,7 +210,7 @@ static void AssignSegments(VP8Encoder* const enc,
VP8MBInfo* const mb = &enc->mb_info_[n];
const int alpha = mb->alpha_;
mb->segment_ = map[alpha];
- mb->alpha_ = centers[map[alpha]]; // for the record.
+ mb->alpha_ = centers[map[alpha]]; // just for the record.
}
if (nb > 1) {
@@ -217,6 +218,7 @@ static void AssignSegments(VP8Encoder* const enc,
if (smooth) SmoothSegmentMap(enc);
}
+ SetSegmentProbas(enc); // Assign final proba
SetSegmentAlphas(enc, centers, weighted_average); // pick some alphas.
}
@@ -225,32 +227,24 @@ 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
-// (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
+// 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.
#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_ >= FAST_ANALYSIS_METHOD) ? MAX_INTRA16_MODE
- : NUM_PRED_MODES;
+ const int max_mode = (it->enc_->method_ >= 3) ? MAX_INTRA16_MODE : 4;
int mode;
- int best_alpha = DEFAULT_ALPHA;
+ int best_alpha = -1;
int best_mode = 0;
VP8MakeLuma16Preds(it);
for (mode = 0; mode < max_mode; ++mode) {
- VP8Histogram histo = { { 0 } };
- int alpha;
-
- VP8CollectHistogram(it->yuv_in_ + Y_OFF,
- it->yuv_p_ + VP8I16ModeOffsets[mode],
- 0, 16, &histo);
- alpha = GetAlpha(&histo);
- if (IS_BETTER_ALPHA(alpha, best_alpha)) {
+ const int alpha = VP8CollectHistogram(it->yuv_in_ + Y_OFF,
+ it->yuv_p_ + VP8I16ModeOffsets[mode],
+ 0, 16);
+ if (alpha > best_alpha) {
best_alpha = alpha;
best_mode = mode;
}
@@ -262,63 +256,46 @@ 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_ >= FAST_ANALYSIS_METHOD) ? MAX_INTRA4_MODE
- : NUM_BMODES;
- int i4_alpha;
- VP8Histogram total_histo = { { 0 } };
- int cur_histo = 0;
-
+ const int max_mode = (it->enc_->method_ >= 3) ? MAX_INTRA4_MODE : NUM_BMODES;
+ int i4_alpha = 0;
VP8IteratorStartI4(it);
do {
int mode;
- int best_mode_alpha = DEFAULT_ALPHA;
- VP8Histogram histos[2];
+ int best_mode_alpha = -1;
const uint8_t* const src = it->yuv_in_ + Y_OFF + VP8Scan[it->i4_];
VP8MakeIntra4Preds(it);
for (mode = 0; mode < max_mode; ++mode) {
- int alpha;
-
- memset(&histos[cur_histo], 0, sizeof(histos[cur_histo]));
- VP8CollectHistogram(src, it->yuv_p_ + VP8I4ModeOffsets[mode],
- 0, 1, &histos[cur_histo]);
- alpha = GetAlpha(&histos[cur_histo]);
- if (IS_BETTER_ALPHA(alpha, best_mode_alpha)) {
+ const int alpha = VP8CollectHistogram(src,
+ it->yuv_p_ + VP8I4ModeOffsets[mode],
+ 0, 1);
+ if (alpha > best_mode_alpha) {
best_mode_alpha = alpha;
modes[it->i4_] = mode;
- cur_histo ^= 1; // keep track of best histo so far.
}
}
- // accumulate best histogram
- MergeHistograms(&histos[cur_histo ^ 1], &total_histo);
+ i4_alpha += best_mode_alpha;
// Note: we reuse the original samples for predictors
} while (VP8IteratorRotateI4(it, it->yuv_in_ + Y_OFF));
- i4_alpha = GetAlpha(&total_histo);
- if (IS_BETTER_ALPHA(i4_alpha, best_alpha)) {
+ if (i4_alpha > best_alpha) {
VP8SetIntra4Mode(it, modes);
- best_alpha = i4_alpha;
+ best_alpha = ClipAlpha(i4_alpha);
}
return best_alpha;
}
static int MBAnalyzeBestUVMode(VP8EncIterator* const it) {
- int best_alpha = DEFAULT_ALPHA;
+ int best_alpha = -1;
int best_mode = 0;
- const int max_mode =
- (it->enc_->method_ >= FAST_ANALYSIS_METHOD) ? MAX_UV_MODE
- : NUM_PRED_MODES;
+ const int max_mode = (it->enc_->method_ >= 3) ? MAX_UV_MODE : 4;
int mode;
VP8MakeChroma8Preds(it);
for (mode = 0; mode < max_mode; ++mode) {
- VP8Histogram histo = { { 0 } };
- int alpha;
- VP8CollectHistogram(it->yuv_in_ + U_OFF,
- it->yuv_p_ + VP8UVModeOffsets[mode],
- 16, 16 + 4 + 4, &histo);
- alpha = GetAlpha(&histo);
- if (IS_BETTER_ALPHA(alpha, best_alpha)) {
+ const int alpha = VP8CollectHistogram(it->yuv_in_ + U_OFF,
+ it->yuv_p_ + VP8UVModeOffsets[mode],
+ 16, 16 + 4 + 4);
+ if (alpha > best_alpha) {
best_alpha = alpha;
best_mode = mode;
}
@@ -328,8 +305,7 @@ static int MBAnalyzeBestUVMode(VP8EncIterator* const it) {
}
static void MBAnalyze(VP8EncIterator* const it,
- int alphas[MAX_ALPHA + 1],
- int* const alpha, int* const uv_alpha) {
+ int alphas[256], int* const uv_alpha) {
const VP8Encoder* const enc = it->enc_;
int best_alpha, best_uv_alpha;
@@ -338,7 +314,7 @@ static void MBAnalyze(VP8EncIterator* const it,
VP8SetSegment(it, 0); // default segment, spec-wise.
best_alpha = MBAnalyzeBestIntra16Mode(it);
- if (enc->method_ >= 5) {
+ if (enc->method_ != 3) {
// 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.
@@ -348,22 +324,10 @@ static void MBAnalyze(VP8EncIterator* const it,
best_uv_alpha = MBAnalyzeBestUVMode(it);
// Final susceptibility mix
- best_alpha = (3 * best_alpha + best_uv_alpha + 2) >> 2;
- best_alpha = FinalAlphaValue(best_alpha);
+ best_alpha = (best_alpha + best_uv_alpha + 1) / 2;
alphas[best_alpha]++;
- it->mb_->alpha_ = best_alpha; // for later remapping.
-
- // Accumulate for later complexity analysis.
- *alpha += best_alpha; // mixed susceptibility (not just luma)
*uv_alpha += best_uv_alpha;
-}
-
-static void DefaultMBInfo(VP8MBInfo* const mb) {
- mb->type_ = 1; // I16x16
- mb->uv_mode_ = 0;
- mb->skip_ = 0; // not skipped
- mb->segment_ = 0; // default segment
- mb->alpha_ = 0;
+ it->mb_->alpha_ = best_alpha; // Informative only.
}
//------------------------------------------------------------------------------
@@ -376,122 +340,25 @@ static void DefaultMBInfo(VP8MBInfo* const mb) {
// and decide intra4/intra16, but that's usually almost always a bad choice at
// this stage.
-static void ResetAllMBInfo(VP8Encoder* const enc) {
- int n;
- for (n = 0; n < enc->mb_w_ * enc->mb_h_; ++n) {
- DefaultMBInfo(&enc->mb_info_[n]);
- }
- // Default susceptibilities.
- enc->dqm_[0].alpha_ = 0;
- enc->dqm_[0].beta_ = 0;
- // Note: we can't compute this alpha_ / uv_alpha_ -> set to default value.
- enc->alpha_ = 0;
- enc->uv_alpha_ = 0;
- WebPReportProgress(enc->pic_, enc->percent_ + 20, &enc->percent_);
-}
-
-// struct used to collect job result
-typedef struct {
- WebPWorker worker;
- int alphas[MAX_ALPHA + 1];
- int alpha, uv_alpha;
- VP8EncIterator it;
- int delta_progress;
-} SegmentJob;
-
-// main work call
-static int DoSegmentsJob(SegmentJob* const job, VP8EncIterator* const it) {
+int VP8EncAnalyze(VP8Encoder* const enc) {
int ok = 1;
- if (!VP8IteratorIsDone(it)) {
- uint8_t tmp[32 + ALIGN_CST];
- uint8_t* const scratch = (uint8_t*)DO_ALIGN(tmp);
- do {
- // Let's pretend we have perfect lossless reconstruction.
- VP8IteratorImport(it, scratch);
- MBAnalyze(it, job->alphas, &job->alpha, &job->uv_alpha);
- ok = VP8IteratorProgress(it, job->delta_progress);
- } while (ok && VP8IteratorNext(it));
- }
- return ok;
-}
-
-static void MergeJobs(const SegmentJob* const src, SegmentJob* const dst) {
- int i;
- for (i = 0; i <= MAX_ALPHA; ++i) dst->alphas[i] += src->alphas[i];
- dst->alpha += src->alpha;
- dst->uv_alpha += src->uv_alpha;
-}
+ int alphas[256] = { 0 };
+ VP8EncIterator it;
-// initialize the job struct with some TODOs
-static void InitSegmentJob(VP8Encoder* const enc, SegmentJob* const job,
- int start_row, int end_row) {
- WebPWorkerInit(&job->worker);
- job->worker.data1 = job;
- job->worker.data2 = &job->it;
- job->worker.hook = (WebPWorkerHook)DoSegmentsJob;
- VP8IteratorInit(enc, &job->it);
- VP8IteratorSetRow(&job->it, start_row);
- VP8IteratorSetCountDown(&job->it, (end_row - start_row) * enc->mb_w_);
- memset(job->alphas, 0, sizeof(job->alphas));
- job->alpha = 0;
- job->uv_alpha = 0;
- // only one of both jobs can record the progress, since we don't
- // expect the user's hook to be multi-thread safe
- job->delta_progress = (start_row == 0) ? 20 : 0;
-}
+ VP8IteratorInit(enc, &it);
+ enc->uv_alpha_ = 0;
+ do {
+ VP8IteratorImport(&it);
+ MBAnalyze(&it, alphas, &enc->uv_alpha_);
+ ok = VP8IteratorProgress(&it, 20);
+ // Let's pretend we have perfect lossless reconstruction.
+ } while (ok && VP8IteratorNext(&it, it.yuv_in_));
+ enc->uv_alpha_ /= enc->mb_w_ * enc->mb_h_;
+ if (ok) AssignSegments(enc, alphas);
-// main entry point
-int VP8EncAnalyze(VP8Encoder* const enc) {
- int ok = 1;
- const int do_segments =
- enc->config_->emulate_jpeg_size || // We need the complexity evaluation.
- (enc->segment_hdr_.num_segments_ > 1) ||
- (enc->method_ == 0); // for method 0, we need preds_[] to be filled.
- if (do_segments) {
- const int last_row = enc->mb_h_;
- // We give a little more than a half work to the main thread.
- const int split_row = (9 * last_row + 15) >> 4;
- const int total_mb = last_row * enc->mb_w_;
-#ifdef WEBP_USE_THREAD
- const int kMinSplitRow = 2; // minimal rows needed for mt to be worth it
- const int do_mt = (enc->thread_level_ > 0) && (split_row >= kMinSplitRow);
-#else
- const int do_mt = 0;
-#endif
- SegmentJob main_job;
- if (do_mt) {
- SegmentJob side_job;
- // Note the use of '&' instead of '&&' because we must call the functions
- // no matter what.
- InitSegmentJob(enc, &main_job, 0, split_row);
- InitSegmentJob(enc, &side_job, split_row, last_row);
- // we don't need to call Reset() on main_job.worker, since we're calling
- // WebPWorkerExecute() on it
- ok &= WebPWorkerReset(&side_job.worker);
- // launch the two jobs in parallel
- if (ok) {
- WebPWorkerLaunch(&side_job.worker);
- WebPWorkerExecute(&main_job.worker);
- ok &= WebPWorkerSync(&side_job.worker);
- ok &= WebPWorkerSync(&main_job.worker);
- }
- WebPWorkerEnd(&side_job.worker);
- if (ok) MergeJobs(&side_job, &main_job); // merge results together
- } else {
- // Even for single-thread case, we use the generic Worker tools.
- InitSegmentJob(enc, &main_job, 0, last_row);
- WebPWorkerExecute(&main_job.worker);
- ok &= WebPWorkerSync(&main_job.worker);
- }
- WebPWorkerEnd(&main_job.worker);
- if (ok) {
- enc->alpha_ = main_job.alpha / total_mb;
- enc->uv_alpha_ = main_job.uv_alpha / total_mb;
- AssignSegments(enc, main_job.alphas);
- }
- } else { // Use only one default segment.
- ResetAllMBInfo(enc);
- }
return ok;
}
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 23:51:44 +0000