// 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.

// -----------------------------------------------------------------------------

//

// WebP encoder: main entry point

//

// Author: Skal (pascal.massimino@gmail.com)

#include <assert.h>

#include <math.h>

#include <stdlib.h>

#include <string.h>

#include "src/dec/common_dec.h"

#include "src/dsp/dsp.h"

#include "src/enc/cost_enc.h"

#include "src/enc/vp8i_enc.h"

#include "src/enc/vp8li_enc.h"

#include "src/utils/utils.h"

#include "src/webp/encode.h"

#include "src/webp/types.h"

// #define PRINT_MEMORY_INFO

#ifdef PRINT_MEMORY_INFO

#include <stdio.h>

#endif

//------------------------------------------------------------------------------

int WebPGetEncoderVersion(void) {

  return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;

}

//------------------------------------------------------------------------------

// VP8Encoder

//------------------------------------------------------------------------------

static void ResetSegmentHeader(VP8Encoder* const enc) {

  VP8EncSegmentHeader* 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) {

  VP8EncFilterHeader* 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

}

// Mapping from config->method to coding tools used.

//-------------------+---+---+---+---+---+---+---+

//   Method          | 0 | 1 | 2 | 3 |(4)| 5 | 6 |

//-------------------+---+---+---+---+---+---+---+

// fast probe        | x |   |   | x |   |   |   |

//-------------------+---+---+---+---+---+---+---+

// dynamic proba     | ~ | x | x | x | x | x | x |

//-------------------+---+---+---+---+---+---+---+

// fast mode analysis|[x]|[x]|   |   | x | x | x |

//-------------------+---+---+---+---+---+---+---+

// basic rd-opt      |   |   |   | x | x | x | x |

//-------------------+---+---+---+---+---+---+---+

// disto-refine i4/16| x | x | x |   |   |   |   |

//-------------------+---+---+---+---+---+---+---+

// disto-refine uv   |   | x | x |   |   |   |   |

//-------------------+---+---+---+---+---+---+---+

// rd-opt i4/16      |   |   | ~ | x | x | x | x |

//-------------------+---+---+---+---+---+---+---+

// token buffer (opt)|   |   |   | x | x | x | x |

//-------------------+---+---+---+---+---+---+---+

// Trellis           |   |   |   |   |   | x |Ful|

//-------------------+---+---+---+---+---+---+---+

// full-SNS          |   |   |   |   | x | x | x |

//-------------------+---+---+---+---+---+---+---+

static void MapConfigToTools(VP8Encoder* const enc) {

  const WebPConfig* const config = enc->config;

  const int method = config->method;

  const int limit = 100 - config->partition_limit;

  enc->method = method;

  enc->rd_opt_level = (method >= 6)   ? RD_OPT_TRELLIS_ALL

                      : (method >= 5) ? RD_OPT_TRELLIS

                      : (method >= 3) ? RD_OPT_BASIC

                                      : RD_OPT_NONE;

  enc->max_i4_header_bits =

      256 * 16 * 16 *                 // upper bound: up to 16bit per 4x4 block

      (limit * limit) / (100 * 100);  // ... modulated with a quadratic curve.

  // partition0 = 512k max.

  enc->mb_header_limit =

      (score_t)256 * 510 * 8 * 1024 / (enc->mb_w * enc->mb_h);

  enc->thread_level = config->thread_level;

  enc->do_search = (config->target_size > 0 || config->target_PSNR > 0);

  if (!config->low_memory) {

#if !defined(DISABLE_TOKEN_BUFFER)

    enc->use_tokens = (enc->rd_opt_level >= RD_OPT_BASIC);  // need rd stats

#endif

    if (enc->use_tokens) {

      enc->num_parts = 1;  // doesn't work with multi-partition

    }

  }

}

// Memory scaling with dimensions:

//  memory (bytes) ~= 2.25 * w + 0.0625 * w * h

//

// Typical memory footprint (614x440 picture)

//              encoder: 22111

//                 info: 4368

//                preds: 17741

//          top samples: 1263

//             non-zero: 175

//             lf-stats: 0

//                total: 45658

// Transient object sizes:

//       VP8EncIterator: 3360

//         VP8ModeScore: 872

//       VP8SegmentInfo: 732

//          VP8EncProba: 18352

//              LFStats: 2048

// Picture size (yuv): 419328

static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,

                                  WebPPicture* const picture) {

  VP8Encoder* enc;

  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(*enc->preds);

  const int top_stride = mb_w * 16;

  const size_t nz_size = (mb_w + 1) * sizeof(*enc->nz) + WEBP_ALIGN_CST;

  const size_t info_size = mb_w * mb_h * sizeof(*enc->mb_info);

  const size_t samples_size =

      2 * top_stride * sizeof(*enc->y_top)  // top-luma/u/v

      + WEBP_ALIGN_CST;                     // align all

  const size_t lf_stats_size =

      config->autofilter ? sizeof(*enc->lf_stats) + WEBP_ALIGN_CST : 0;

  const size_t top_derr_size =

      (config->quality <= ERROR_DIFFUSION_QUALITY || config->pass > 1)

          ? mb_w * sizeof(*enc->top_derr)

          : 0;

  uint8_t* mem;

  const uint64_t size = (uint64_t)sizeof(*enc)  // main struct

                        + WEBP_ALIGN_CST        // cache alignment

                        + info_size             // modes info

                        + preds_size            // prediction modes

                        + samples_size          // top/left samples

                        + top_derr_size         // top diffusion error

                        + nz_size               // coeff context bits

                        + lf_stats_size;        // autofilter stats

#ifdef PRINT_MEMORY_INFO

  printf("===================================\n");

  printf(

      "Memory used:\n"

      "             encoder: %ld\n"

      "                info: %ld\n"

      "               preds: %ld\n"

      "         top samples: %ld\n"

      "       top diffusion: %ld\n"

      "            non-zero: %ld\n"

      "            lf-stats: %ld\n"

      "               total: %ld\n",

      sizeof(*enc) + WEBP_ALIGN_CST, info_size, preds_size, samples_size,

      top_derr_size, nz_size, lf_stats_size, size);

  printf(

      "Transient object sizes:\n"

      "      VP8EncIterator: %ld\n"

      "        VP8ModeScore: %ld\n"

      "      VP8SegmentInfo: %ld\n"

      "         VP8EncProba: %ld\n"

      "             LFStats: %ld\n",

      sizeof(VP8EncIterator), sizeof(VP8ModeScore), sizeof(VP8SegmentInfo),

      sizeof(VP8EncProba), sizeof(LFStats));

  printf("Picture size (yuv): %ld\n", mb_w * mb_h * 384 * sizeof(uint8_t));

  printf("===================================\n");

#endif

  mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));

  if (mem == NULL) {

    WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);

    return NULL;

  }

  enc = (VP8Encoder*)mem;

  mem = (uint8_t*)WEBP_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->mb_info = (VP8MBInfo*)mem;

  mem += info_size;

  enc->preds = mem + 1 + enc->preds_w;

  mem += preds_size;

  enc->nz = 1 + (uint32_t*)WEBP_ALIGN(mem);

  mem += nz_size;

  enc->lf_stats = lf_stats_size ? (LFStats*)WEBP_ALIGN(mem) : NULL;

  mem += lf_stats_size;

  // top samples (all 16-aligned)

  mem = (uint8_t*)WEBP_ALIGN(mem);

  enc->y_top = mem;

  enc->uv_top = enc->y_top + top_stride;

  mem += 2 * top_stride;

  enc->top_derr = top_derr_size ? (DError*)mem : NULL;

  mem += top_derr_size;

  assert(mem <= (uint8_t*)enc + size);

  enc->config = config;

  enc->profile = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;

  enc->pic = picture;

  enc->percent = 0;

  MapConfigToTools(enc);

  VP8EncDspInit();

  VP8DefaultProbas(enc);

  ResetSegmentHeader(enc);

  ResetFilterHeader(enc);

  ResetBoundaryPredictions(enc);

  VP8EncDspCostInit();

  VP8EncInitAlpha(enc);

  // lower quality means smaller output -> we modulate a little the page

  // size based on quality. This is just a crude 1rst-order prediction.

  {

    const float scale = 1.f + config->quality * 5.f / 100.f;  // in [1,6]

    VP8TBufferInit(&enc->tokens, (int)(mb_w * mb_h * 4 * scale));

  }

  return enc;

}

static int DeleteVP8Encoder(VP8Encoder* enc) {

  int ok = 1;

  if (enc != NULL) {

    ok = VP8EncDeleteAlpha(enc);

    VP8TBufferClear(&enc->tokens);

    WebPSafeFree(enc);

  }

  return ok;

}

//------------------------------------------------------------------------------

#if !defined(WEBP_DISABLE_STATS)

static double GetPSNR(uint64_t err, uint64_t size) {

  return (err > 0 && size > 0) ? 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);

  stats->PSNR[4] = (float)GetPSNR(sse[3], size);

}

#endif  // !defined(WEBP_DISABLE_STATS)

static void StoreStats(VP8Encoder* const enc) {

#if !defined(WEBP_DISABLE_STATS)

  WebPAuxStats* const stats = enc->pic->stats;

  if (stats != NULL) {

    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];

    }

  }

#else   // defined(WEBP_DISABLE_STATS)

  WebPReportProgress(enc->pic, 100, &enc->percent);  // done!

#endif  // !defined(WEBP_DISABLE_STATS)

}

int WebPEncodingSetError(const WebPPicture* const pic,

                         WebPEncodingError error) {

  assert((int)error < VP8_ENC_ERROR_LAST);

  assert((int)error >= VP8_ENC_OK);

  // The oldest error reported takes precedence over the new one.

  if (pic->error_code == VP8_ENC_OK) {

    ((WebPPicture*)pic)->error_code = error;

  }

  return 0;

}

int WebPReportProgress(const WebPPicture* const pic, int percent,

                       int* const percent_store) {

  if (percent_store != NULL && percent != *percent_store) {

    *percent_store = percent;

    if (pic->progress_hook && !pic->progress_hook(percent, pic)) {

      // user abort requested

      return WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);

    }

  }

  return 1;  // ok

}

//------------------------------------------------------------------------------

int WebPEncode(const WebPConfig* config, WebPPicture* pic) {

  int ok = 0;

  if (pic == NULL) return 0;

  pic->error_code = 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 (!WebPValidatePicture(pic)) return 0;

  if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION) {

    return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);

  }

  if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));

  if (!config->lossless) {

    VP8Encoder* enc = NULL;

    if (pic->use_argb || pic->y == NULL || pic->u == NULL || pic->v == NULL) {

      // Make sure we have YUVA samples.

      if (config->use_sharp_yuv || (config->preprocessing & 4)) {

        if (!WebPPictureSharpARGBToYUVA(pic)) {

          return 0;

        }

      } else {

        float dithering = 0.f;

        if (config->preprocessing & 2) {

          const float x = config->quality / 100.f;

          const float x2 = x * x;

          // slowly decreasing from max dithering at low quality (q->0)

          // to 0.5 dithering amplitude at high quality (q->100)

          dithering = 1.0f + (0.5f - 1.0f) * x2 * x2;

        }

        if (!WebPPictureARGBToYUVADithered(pic, WEBP_YUV420, dithering)) {

          return 0;

        }

      }

    }

    if (!config->exact) {

      WebPCleanupTransparentArea(pic);

    }

    enc = InitVP8Encoder(config, pic);

    if (enc == NULL) return 0;  // pic->error is already set.

    // Note: each of the tasks below account for 20% in the progress report.

    ok = VP8EncAnalyze(enc);

    // Analysis is done, proceed to actual coding.

    ok = ok && VP8EncStartAlpha(enc);  // possibly done in parallel

    if (!enc->use_tokens) {

      ok = ok && VP8EncLoop(enc);

    } else {

      ok = ok && VP8EncTokenLoop(enc);

    }

    ok = ok && VP8EncFinishAlpha(enc);

    ok = ok && VP8EncWrite(enc);

    StoreStats(enc);

    if (!ok) {

      VP8EncFreeBitWriters(enc);

    }

    ok &= DeleteVP8Encoder(enc);  // must always be called, even if !ok

  } else {

    // Make sure we have ARGB samples.

    if (pic->argb == NULL && !WebPPictureYUVAToARGB(pic)) {

      return 0;

    }

    if (!config->exact) {

      WebPReplaceTransparentPixels(pic, 0x000000);

    }

    ok = VP8LEncodeImage(config, pic);  // Sets pic->error in case of problem.

  }

  return ok;

}