// Copyright 2011 Google Inc.
//
// 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/
// -----------------------------------------------------------------------------
//
// WebP encoder: main entry point
//
// Author: Skal (pascal.massimino@gmail.com)
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "vp8enci.h"
// #define PRINT_MEMORY_INFO
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
#ifdef PRINT_MEMORY_INFO
#include <stdio.h>
#endif
#define MAX_DIMENSION 16384 // maximum width/height allowed by the spec
//-----------------------------------------------------------------------------
int WebPGetEncoderVersion(void) {
return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;
}
//-----------------------------------------------------------------------------
// WebPPicture
//-----------------------------------------------------------------------------
static int DummyWriter(const uint8_t* data, size_t data_size,
const WebPPicture* const picture) {
// The following are to prevent 'unused variable' error message.
(void)data;
(void)data_size;
(void)picture;
return 1;
}
int WebPPictureInitInternal(WebPPicture* const picture, int version) {
if (version != WEBP_ENCODER_ABI_VERSION) {
return 0; // caller/system version mismatch!
}
if (picture) {
memset(picture, 0, sizeof(*picture));
picture->writer = DummyWriter;
WebPEncodingSetError(picture, VP8_ENC_OK);
}
return 1;
}
//-----------------------------------------------------------------------------
// VP8Encoder
//-----------------------------------------------------------------------------
static void ResetSegmentHeader(VP8Encoder* const enc) {
VP8SegmentHeader* const hdr = &enc->segment_hdr_;
hdr->num_segments_ = enc->config_->segments;
hdr->update_map_ = (hdr->num_segments_ > 1);
hdr->size_ = 0;
}
static void ResetFilterHeader(VP8Encoder* const enc) {
VP8FilterHeader* const hdr = &enc->filter_hdr_;
hdr->simple_ = 1;
hdr->level_ = 0;
hdr->sharpness_ = 0;
hdr->i4x4_lf_delta_ = 0;
}
static void ResetBoundaryPredictions(VP8Encoder* const enc) {
// init boundary values once for all
// Note: actually, initializing the preds_[] is only needed for intra4.
int i;
uint8_t* const top = enc->preds_ - enc->preds_w_;
uint8_t* const left = enc->preds_ - 1;
for (i = -1; i < 4 * enc->mb_w_; ++i) {
top[i] = B_DC_PRED;
}
for (i = 0; i < 4 * enc->mb_h_; ++i) {
left[i * enc->preds_w_] = B_DC_PRED;
}
enc->nz_[-1] = 0; // constant
}
// Map configured quality level to coding tools used.
//-------------+---+---+---+---+---+---+
// Quality | 0 | 1 | 2 | 3 | 4 | 5 +
//-------------+---+---+---+---+---+---+
// dynamic prob| ~ | x | x | x | x | x |
//-------------+---+---+---+---+---+---+
// rd-opt modes| | | x | x | x | x |
//-------------+---+---+---+---+---+---+
// fast i4/i16 | x | x | | | | |
//-------------+---+---+---+---+---+---+
// rd-opt i4/16| | | x | x | x | x |
//-------------+---+---+---+---+---+---+
// Trellis | | x | | | x | x |
//-------------+---+---+---+---+---+---+
// full-SNS | | | | | | x |
//-------------+---+---+---+---+---+---+
static void MapConfigToTools(VP8Encoder* const enc) {
const int method = enc->config_->method;
enc->method_ = method;
enc->rd_opt_level_ = (method >= 6) ? 3
: (method >= 5) ? 2
: (method >= 3) ? 1
: 0;
}
// Memory scaling with dimensions:
// memory (bytes) ~= 2.25 * w + 0.0625 * w * h
//
// Typical memory footprint (768x510 picture)
// Memory used:
// encoder: 33919
// block cache: 2880
// info: 3072
// preds: 24897
// top samples: 1623
// non-zero: 196
// lf-stats: 2048
// total: 68635
// Transcient object sizes:
// VP8EncIterator: 352
// VP8ModeScore: 912
// VP8SegmentInfo: 532
// VP8Proba: 31032
// LFStats: 2048
// Picture size (yuv): 589824
static VP8Encoder* InitEncoder(const WebPConfig* const config,
WebPPicture* const picture) {
const int use_filter =
(config->filter_strength > 0) || (config->autofilter > 0);
const int mb_w = (picture->width + 15) >> 4;
const int mb_h = (picture->height + 15) >> 4;
const int preds_w = 4 * mb_w + 1;
const int preds_h = 4 * mb_h + 1;
const size_t preds_size = preds_w * preds_h * sizeof(uint8_t);
const int top_stride = mb_w * 16;
const size_t nz_size = (mb_w + 1) * sizeof(uint32_t);
const size_t cache_size = (3 * YUV_SIZE + PRED_SIZE) * sizeof(uint8_t);
const size_t info_size = mb_w * mb_h * sizeof(VP8MBInfo);
const size_t samples_size = (2 * top_stride + // top-luma/u/v
16 + 16 + 16 + 8 + 1 + // left y/u/v
2 * ALIGN_CST) // align all
* sizeof(uint8_t);
const size_t lf_stats_size =
config->autofilter ? sizeof(LFStats) + ALIGN_CST : 0;
VP8Encoder* enc;
uint8_t* mem;
size_t size = sizeof(VP8Encoder) + ALIGN_CST // main struct
+ cache_size // working caches
+ info_size // modes info
+ preds_size // prediction modes
+ samples_size // top/left samples
+ nz_size // coeff context bits
+ lf_stats_size; // autofilter stats
#ifdef PRINT_MEMORY_INFO
printf("===================================\n");
printf("Memory used:\n"
" encoder: %ld\n"
" block cache: %ld\n"
" info: %ld\n"
" preds: %ld\n"
" top samples: %ld\n"
" non-zero: %ld\n"
" lf-stats: %ld\n"
" total: %ld\n",
sizeof(VP8Encoder) + ALIGN_CST, cache_size, info_size,
preds_size, samples_size, nz_size, lf_stats_size, size);
printf("Transcient object sizes:\n"
" VP8EncIterator: %ld\n"
" VP8ModeScore: %ld\n"
" VP8SegmentInfo: %ld\n"
" VP8Proba: %ld\n"
" LFStats: %ld\n",
sizeof(VP8EncIterator), sizeof(VP8ModeScore),
sizeof(VP8SegmentInfo), sizeof(VP8Proba),
sizeof(LFStats));
printf("Picture size (yuv): %ld\n",
mb_w * mb_h * 384 * sizeof(uint8_t));
printf("===================================\n");
#endif
mem = (uint8_t*)malloc(size);
if (mem == NULL) {
WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
return NULL;
}
enc = (VP8Encoder*)mem;
mem = (uint8_t*)DO_ALIGN(mem + sizeof(*enc));
memset(enc, 0, sizeof(*enc));
enc->num_parts_ = 1 << config->partitions;
enc->mb_w_ = mb_w;
enc->mb_h_ = mb_h;
enc->preds_w_ = preds_w;
enc->yuv_in_ = (uint8_t*)mem;
mem += YUV_SIZE;
enc->yuv_out_ = (uint8_t*)mem;
mem += YUV_SIZE;
enc->yuv_out2_ = (uint8_t*)mem;
mem += YUV_SIZE;
enc->yuv_p_ = (uint8_t*)mem;
mem += PRED_SIZE;
enc->mb_info_ = (VP8MBInfo*)mem;
mem += info_size;
enc->preds_ = ((uint8_t*)mem) + 1 + enc->preds_w_;
mem += preds_w * preds_h * sizeof(uint8_t);
enc->nz_ = 1 + (uint32_t*)mem;
mem += nz_size;
enc->lf_stats_ = lf_stats_size ? (LFStats*)DO_ALIGN(mem) : NULL;
mem += lf_stats_size;
// top samples (all 16-aligned)
mem = (uint8_t*)DO_ALIGN(mem);
enc->y_top_ = (uint8_t*)mem;
enc->uv_top_ = enc->y_top_ + top_stride;
mem += 2 * top_stride;
mem = (uint8_t*)DO_ALIGN(mem + 1);
enc->y_left_ = (uint8_t*)mem;
mem += 16 + 16;
enc->u_left_ = (uint8_t*)mem;
mem += 16;
enc->v_left_ = (uint8_t*)mem;
mem += 8;
enc->config_ = config;
enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
enc->pic_ = picture;
MapConfigToTools(enc);
VP8EncDspInit();
VP8DefaultProbas(enc);
ResetSegmentHeader(enc);
ResetFilterHeader(enc);
ResetBoundaryPredictions(enc);
#ifdef WEBP_EXPERIMENTAL_FEATURES
VP8EncInitAlpha(enc);
VP8EncInitLayer(enc);
#endif
return enc;
}
static void DeleteEncoder(VP8Encoder* enc) {
if (enc) {
#ifdef WEBP_EXPERIMENTAL_FEATURES
VP8EncDeleteAlpha(enc);
VP8EncDeleteLayer(enc);
#endif
free(enc);
}
}
//-----------------------------------------------------------------------------
static double GetPSNR(uint64_t err, uint64_t size) {
return err ? 10. * log10(255. * 255. * size / err) : 99.;
}
static void FinalizePSNR(const VP8Encoder* const enc) {
WebPAuxStats* stats = enc->pic_->stats;
const uint64_t size = enc->sse_count_;
const uint64_t* const sse = enc->sse_;
stats->PSNR[0] = (float)GetPSNR(sse[0], size);
stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
}
static void StoreStats(VP8Encoder* const enc) {
WebPAuxStats* const stats = enc->pic_->stats;
if (stats) {
int i, s;
for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
stats->segment_level[i] = enc->dqm_[i].fstrength_;
stats->segment_quant[i] = enc->dqm_[i].quant_;
for (s = 0; s <= 2; ++s) {
stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
}
}
FinalizePSNR(enc);
stats->coded_size = enc->coded_size_;
for (i = 0; i < 3; ++i) {
stats->block_count[i] = enc->block_count_[i];
}
}
}
int WebPEncodingSetError(WebPPicture* const pic, WebPEncodingError error) {
assert((int)error <= VP8_ENC_ERROR_BAD_WRITE);
assert((int)error >= VP8_ENC_OK);
pic->error_code = error;
return 0;
}
//-----------------------------------------------------------------------------
int WebPEncode(const WebPConfig* const config, WebPPicture* const pic) {
VP8Encoder* enc;
int ok;
if (pic == NULL)
return 0;
WebPEncodingSetError(pic, VP8_ENC_OK); // all ok so far
if (config == NULL) // bad params
return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
if (!WebPValidateConfig(config))
return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
if (pic->width <= 0 || pic->height <= 0)
return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
if (pic->y == NULL || pic->u == NULL || pic->v == NULL)
return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
if (pic->width >= MAX_DIMENSION || pic->height >= MAX_DIMENSION)
return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
enc = InitEncoder(config, pic);
if (enc == NULL) return 0; // pic->error is already set.
ok = VP8EncAnalyze(enc)
&& VP8StatLoop(enc)
&& VP8EncLoop(enc)
#ifdef WEBP_EXPERIMENTAL_FEATURES
&& VP8EncFinishAlpha(enc)
&& VP8EncFinishLayer(enc)
#endif
&& VP8EncWrite(enc);
StoreStats(enc);
DeleteEncoder(enc);
return ok;
}
#if defined(__cplusplus) || defined(c_plusplus)
} // extern "C"
#endif