Adding libwebp: Adding clean copy of libwebp 0.4.0

This commit imports libwebp 0.4.0, including AUTHORS, COPYING, ChangeLog,
NEWS, PATENTS, README and src directories. In src, only includes header
and source files.

The patches required to build it in Qt will follow in separate
commit(s).

Task-number: QTBUG-14205
Change-Id: I747918fe2a07716f66cffb795129f7aa5e067759
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

1 files changed, 570 insertions, 0 deletions

diff --git a/src/3rdparty/libwebp/src/enc/vp8enci.h b/src/3rdparty/libwebp/src/enc/vp8enci.h
new file mode 100644
index 0000000..71adf6c
--- /dev/null
+++ b/src/3rdparty/libwebp/src/enc/vp8enci.h
@@ -0,0 +1,570 @@
+// 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: internal header.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_ENC_VP8ENCI_H_
+#define WEBP_ENC_VP8ENCI_H_
+
+#include <string.h>     // for memcpy()
+#include "../webp/encode.h"
+#include "../dsp/dsp.h"
+#include "../utils/bit_writer.h"
+#include "../utils/thread.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//------------------------------------------------------------------------------
+// Various defines and enums
+
+// version numbers
+#define ENC_MAJ_VERSION 0
+#define ENC_MIN_VERSION 4
+#define ENC_REV_VERSION 0
+
+// intra prediction modes
+enum { B_DC_PRED = 0,   // 4x4 modes
+       B_TM_PRED = 1,
+       B_VE_PRED = 2,
+       B_HE_PRED = 3,
+       B_RD_PRED = 4,
+       B_VR_PRED = 5,
+       B_LD_PRED = 6,
+       B_VL_PRED = 7,
+       B_HD_PRED = 8,
+       B_HU_PRED = 9,
+       NUM_BMODES = B_HU_PRED + 1 - B_DC_PRED,  // = 10
+
+       // Luma16 or UV modes
+       DC_PRED = B_DC_PRED, V_PRED = B_VE_PRED,
+       H_PRED = B_HE_PRED, TM_PRED = B_TM_PRED,
+       NUM_PRED_MODES = 4
+     };
+
+enum { NUM_MB_SEGMENTS = 4,
+       MAX_NUM_PARTITIONS = 8,
+       NUM_TYPES = 4,   // 0: i16-AC,  1: i16-DC,  2:chroma-AC,  3:i4-AC
+       NUM_BANDS = 8,
+       NUM_CTX = 3,
+       NUM_PROBAS = 11,
+       MAX_LF_LEVELS = 64,       // Maximum loop filter level
+       MAX_VARIABLE_LEVEL = 67,  // last (inclusive) level with variable cost
+       MAX_LEVEL = 2047          // max level (note: max codable is 2047 + 67)
+     };
+
+typedef enum {   // Rate-distortion optimization levels
+  RD_OPT_NONE        = 0,  // no rd-opt
+  RD_OPT_BASIC       = 1,  // basic scoring (no trellis)
+  RD_OPT_TRELLIS     = 2,  // perform trellis-quant on the final decision only
+  RD_OPT_TRELLIS_ALL = 3   // trellis-quant for every scoring (much slower)
+} VP8RDLevel;
+
+// YUV-cache parameters. Cache is 16-pixels wide.
+// The original or reconstructed samples can be accessed using VP8Scan[]
+// The predicted blocks can be accessed using offsets to yuv_p_ and
+// the arrays VP8*ModeOffsets[];
+//         +----+      YUV Samples area. See VP8Scan[] for accessing the blocks.
+//  Y_OFF  |YYYY| <- original samples  ('yuv_in_')
+//         |YYYY|
+//         |YYYY|
+//         |YYYY|
+//  U_OFF  |UUVV| V_OFF  (=U_OFF + 8)
+//         |UUVV|
+//         +----+
+//  Y_OFF  |YYYY| <- compressed/decoded samples  ('yuv_out_')
+//         |YYYY|    There are two buffers like this ('yuv_out_'/'yuv_out2_')
+//         |YYYY|
+//         |YYYY|
+//  U_OFF  |UUVV| V_OFF
+//         |UUVV|
+//          x2 (for yuv_out2_)
+//         +----+     Prediction area ('yuv_p_', size = PRED_SIZE)
+// I16DC16 |YYYY|  Intra16 predictions (16x16 block each)
+//         |YYYY|
+//         |YYYY|
+//         |YYYY|
+// I16TM16 |YYYY|
+//         |YYYY|
+//         |YYYY|
+//         |YYYY|
+// I16VE16 |YYYY|
+//         |YYYY|
+//         |YYYY|
+//         |YYYY|
+// I16HE16 |YYYY|
+//         |YYYY|
+//         |YYYY|
+//         |YYYY|
+//         +----+  Chroma U/V predictions (16x8 block each)
+// C8DC8   |UUVV|
+//         |UUVV|
+// C8TM8   |UUVV|
+//         |UUVV|
+// C8VE8   |UUVV|
+//         |UUVV|
+// C8HE8   |UUVV|
+//         |UUVV|
+//         +----+  Intra 4x4 predictions (4x4 block each)
+//         |YYYY| I4DC4 I4TM4 I4VE4 I4HE4
+//         |YYYY| I4RD4 I4VR4 I4LD4 I4VL4
+//         |YY..| I4HD4 I4HU4 I4TMP
+//         +----+
+#define BPS       16   // this is the common stride
+#define Y_SIZE   (BPS * 16)
+#define UV_SIZE  (BPS * 8)
+#define YUV_SIZE (Y_SIZE + UV_SIZE)
+#define PRED_SIZE (6 * 16 * BPS + 12 * BPS)
+#define Y_OFF    (0)
+#define U_OFF    (Y_SIZE)
+#define V_OFF    (U_OFF + 8)
+#define ALIGN_CST 15
+#define DO_ALIGN(PTR) ((uintptr_t)((PTR) + ALIGN_CST) & ~ALIGN_CST)
+
+extern const int VP8Scan[16 + 4 + 4];           // in quant.c
+extern const int VP8UVModeOffsets[4];           // in analyze.c
+extern const int VP8I16ModeOffsets[4];
+extern const int VP8I4ModeOffsets[NUM_BMODES];
+
+// Layout of prediction blocks
+// intra 16x16
+#define I16DC16 (0 * 16 * BPS)
+#define I16TM16 (1 * 16 * BPS)
+#define I16VE16 (2 * 16 * BPS)
+#define I16HE16 (3 * 16 * BPS)
+// chroma 8x8, two U/V blocks side by side (hence: 16x8 each)
+#define C8DC8 (4 * 16 * BPS)
+#define C8TM8 (4 * 16 * BPS + 8 * BPS)
+#define C8VE8 (5 * 16 * BPS)
+#define C8HE8 (5 * 16 * BPS + 8 * BPS)
+// intra 4x4
+#define I4DC4 (6 * 16 * BPS +  0)
+#define I4TM4 (6 * 16 * BPS +  4)
+#define I4VE4 (6 * 16 * BPS +  8)
+#define I4HE4 (6 * 16 * BPS + 12)
+#define I4RD4 (6 * 16 * BPS + 4 * BPS +  0)
+#define I4VR4 (6 * 16 * BPS + 4 * BPS +  4)
+#define I4LD4 (6 * 16 * BPS + 4 * BPS +  8)
+#define I4VL4 (6 * 16 * BPS + 4 * BPS + 12)
+#define I4HD4 (6 * 16 * BPS + 8 * BPS +  0)
+#define I4HU4 (6 * 16 * BPS + 8 * BPS +  4)
+#define I4TMP (6 * 16 * BPS + 8 * BPS +  8)
+
+typedef int64_t score_t;     // type used for scores, rate, distortion
+#define MAX_COST ((score_t)0x7fffffffffffffLL)
+
+#define QFIX 17
+#define BIAS(b)  ((b) << (QFIX - 8))
+// Fun fact: this is the _only_ line where we're actually being lossy and
+// discarding bits.
+static WEBP_INLINE int QUANTDIV(int n, int iQ, int B) {
+  return (n * iQ + B) >> QFIX;
+}
+
+// size of histogram used by CollectHistogram.
+#define MAX_COEFF_THRESH   31
+typedef struct VP8Histogram VP8Histogram;
+struct VP8Histogram {
+  // TODO(skal): we only need to store the max_value and last_non_zero actually.
+  int distribution[MAX_COEFF_THRESH + 1];
+};
+
+// Uncomment the following to remove token-buffer code:
+// #define DISABLE_TOKEN_BUFFER
+
+//------------------------------------------------------------------------------
+// Headers
+
+typedef uint32_t proba_t;   // 16b + 16b
+typedef uint8_t ProbaArray[NUM_CTX][NUM_PROBAS];
+typedef proba_t StatsArray[NUM_CTX][NUM_PROBAS];
+typedef uint16_t CostArray[NUM_CTX][MAX_VARIABLE_LEVEL + 1];
+typedef double LFStats[NUM_MB_SEGMENTS][MAX_LF_LEVELS];  // filter stats
+
+typedef struct VP8Encoder VP8Encoder;
+
+// segment features
+typedef struct {
+  int num_segments_;      // Actual number of segments. 1 segment only = unused.
+  int update_map_;        // whether to update the segment map or not.
+                          // must be 0 if there's only 1 segment.
+  int size_;              // bit-cost for transmitting the segment map
+} VP8SegmentHeader;
+
+// Struct collecting all frame-persistent probabilities.
+typedef struct {
+  uint8_t segments_[3];     // probabilities for segment tree
+  uint8_t skip_proba_;      // final probability of being skipped.
+  ProbaArray coeffs_[NUM_TYPES][NUM_BANDS];      // 924 bytes
+  StatsArray stats_[NUM_TYPES][NUM_BANDS];       // 4224 bytes
+  CostArray level_cost_[NUM_TYPES][NUM_BANDS];   // 11.4k
+  int dirty_;               // if true, need to call VP8CalculateLevelCosts()
+  int use_skip_proba_;      // Note: we always use skip_proba for now.
+  int nb_skip_;             // number of skipped blocks
+} VP8Proba;
+
+// Filter parameters. Not actually used in the code (we don't perform
+// the in-loop filtering), but filled from user's config
+typedef struct {
+  int simple_;             // filtering type: 0=complex, 1=simple
+  int level_;              // base filter level [0..63]
+  int sharpness_;          // [0..7]
+  int i4x4_lf_delta_;      // delta filter level for i4x4 relative to i16x16
+} VP8FilterHeader;
+
+//------------------------------------------------------------------------------
+// Informations about the macroblocks.
+
+typedef struct {
+  // block type
+  unsigned int type_:2;     // 0=i4x4, 1=i16x16
+  unsigned int uv_mode_:2;
+  unsigned int skip_:1;
+  unsigned int segment_:2;
+  uint8_t alpha_;      // quantization-susceptibility
+} VP8MBInfo;
+
+typedef struct VP8Matrix {
+  uint16_t q_[16];        // quantizer steps
+  uint16_t iq_[16];       // reciprocals, fixed point.
+  uint16_t bias_[16];     // rounding bias
+  uint16_t zthresh_[16];  // value under which a coefficient is zeroed
+  uint16_t sharpen_[16];  // frequency boosters for slight sharpening
+} VP8Matrix;
+
+typedef struct {
+  VP8Matrix y1_, y2_, uv_;  // quantization matrices
+  int alpha_;      // quant-susceptibility, range [-127,127]. Zero is neutral.
+                   // Lower values indicate a lower risk of blurriness.
+  int beta_;       // filter-susceptibility, range [0,255].
+  int quant_;      // final segment quantizer.
+  int fstrength_;  // final in-loop filtering strength
+  int max_edge_;   // max edge delta (for filtering strength)
+  int min_disto_;  // minimum distortion required to trigger filtering record
+  // reactivities
+  int lambda_i16_, lambda_i4_, lambda_uv_;
+  int lambda_mode_, lambda_trellis_, tlambda_;
+  int lambda_trellis_i16_, lambda_trellis_i4_, lambda_trellis_uv_;
+} VP8SegmentInfo;
+
+// Handy transient struct to accumulate score and info during RD-optimization
+// and mode evaluation.
+typedef struct {
+  score_t D, SD;              // Distortion, spectral distortion
+  score_t H, R, score;        // header bits, rate, score.
+  int16_t y_dc_levels[16];    // Quantized levels for luma-DC, luma-AC, chroma.
+  int16_t y_ac_levels[16][16];
+  int16_t uv_levels[4 + 4][16];
+  int mode_i16;               // mode number for intra16 prediction
+  uint8_t modes_i4[16];       // mode numbers for intra4 predictions
+  int mode_uv;                // mode number of chroma prediction
+  uint32_t nz;                // non-zero blocks
+} VP8ModeScore;
+
+// Iterator structure to iterate through macroblocks, pointing to the
+// right neighbouring data (samples, predictions, contexts, ...)
+typedef struct {
+  int x_, y_;                      // current macroblock
+  int y_stride_, uv_stride_;       // respective strides
+  uint8_t*      yuv_in_;           // input samples
+  uint8_t*      yuv_out_;          // output samples
+  uint8_t*      yuv_out2_;         // secondary buffer swapped with yuv_out_.
+  uint8_t*      yuv_p_;            // scratch buffer for prediction
+  VP8Encoder*   enc_;              // back-pointer
+  VP8MBInfo*    mb_;               // current macroblock
+  VP8BitWriter* bw_;               // current bit-writer
+  uint8_t*      preds_;            // intra mode predictors (4x4 blocks)
+  uint32_t*     nz_;               // non-zero pattern
+  uint8_t       i4_boundary_[37];  // 32+5 boundary samples needed by intra4x4
+  uint8_t*      i4_top_;           // pointer to the current top boundary sample
+  int           i4_;               // current intra4x4 mode being tested
+  int           top_nz_[9];        // top-non-zero context.
+  int           left_nz_[9];       // left-non-zero. left_nz[8] is independent.
+  uint64_t      bit_count_[4][3];  // bit counters for coded levels.
+  uint64_t      luma_bits_;        // macroblock bit-cost for luma
+  uint64_t      uv_bits_;          // macroblock bit-cost for chroma
+  LFStats*      lf_stats_;         // filter stats (borrowed from enc_)
+  int           do_trellis_;       // if true, perform extra level optimisation
+  int           count_down_;       // number of mb still to be processed
+  int           count_down0_;      // starting counter value (for progress)
+  int           percent0_;         // saved initial progress percent
+
+  uint8_t* y_left_;    // left luma samples (addressable from index -1 to 15).
+  uint8_t* u_left_;    // left u samples (addressable from index -1 to 7)
+  uint8_t* v_left_;    // left v samples (addressable from index -1 to 7)
+
+  uint8_t* y_top_;     // top luma samples at position 'x_'
+  uint8_t* uv_top_;    // top u/v samples at position 'x_', packed as 16 bytes
+
+  // memory for storing y/u/v_left_ and yuv_in_/out_*
+  uint8_t yuv_left_mem_[17 + 16 + 16 + 8 + ALIGN_CST];     // memory for *_left_
+  uint8_t yuv_mem_[3 * YUV_SIZE + PRED_SIZE + ALIGN_CST];  // memory for yuv_*
+} VP8EncIterator;
+
+  // in iterator.c
+// must be called first
+void VP8IteratorInit(VP8Encoder* const enc, VP8EncIterator* const it);
+// restart a scan
+void VP8IteratorReset(VP8EncIterator* const it);
+// reset iterator position to row 'y'
+void VP8IteratorSetRow(VP8EncIterator* const it, int y);
+// set count down (=number of iterations to go)
+void VP8IteratorSetCountDown(VP8EncIterator* const it, int count_down);
+// return true if iteration is finished
+int VP8IteratorIsDone(const VP8EncIterator* const it);
+// Import uncompressed samples from source.
+// If tmp_32 is not NULL, import boundary samples too.
+// tmp_32 is a 32-bytes scratch buffer that must be aligned in memory.
+void VP8IteratorImport(VP8EncIterator* const it, uint8_t* tmp_32);
+// export decimated samples
+void VP8IteratorExport(const VP8EncIterator* const it);
+// go to next macroblock. Returns false if not finished.
+int VP8IteratorNext(VP8EncIterator* const it);
+// save the yuv_out_ boundary values to top_/left_ arrays for next iterations.
+void VP8IteratorSaveBoundary(VP8EncIterator* const it);
+// Report progression based on macroblock rows. Return 0 for user-abort request.
+int VP8IteratorProgress(const VP8EncIterator* const it,
+                        int final_delta_percent);
+// Intra4x4 iterations
+void VP8IteratorStartI4(VP8EncIterator* const it);
+// returns true if not done.
+int VP8IteratorRotateI4(VP8EncIterator* const it,
+                        const uint8_t* const yuv_out);
+
+// Non-zero context setup/teardown
+void VP8IteratorNzToBytes(VP8EncIterator* const it);
+void VP8IteratorBytesToNz(VP8EncIterator* const it);
+
+// Helper functions to set mode properties
+void VP8SetIntra16Mode(const VP8EncIterator* const it, int mode);
+void VP8SetIntra4Mode(const VP8EncIterator* const it, const uint8_t* modes);
+void VP8SetIntraUVMode(const VP8EncIterator* const it, int mode);
+void VP8SetSkip(const VP8EncIterator* const it, int skip);
+void VP8SetSegment(const VP8EncIterator* const it, int segment);
+
+//------------------------------------------------------------------------------
+// Paginated token buffer
+
+typedef struct VP8Tokens VP8Tokens;  // struct details in token.c
+
+typedef struct {
+#if !defined(DISABLE_TOKEN_BUFFER)
+  VP8Tokens* pages_;        // first page
+  VP8Tokens** last_page_;   // last page
+  uint16_t* tokens_;        // set to (*last_page_)->tokens_
+  int left_;          // how many free tokens left before the page is full.
+#endif
+  int error_;         // true in case of malloc error
+} VP8TBuffer;
+
+void VP8TBufferInit(VP8TBuffer* const b);    // initialize an empty buffer
+void VP8TBufferClear(VP8TBuffer* const b);   // de-allocate pages memory
+
+#if !defined(DISABLE_TOKEN_BUFFER)
+
+// Finalizes bitstream when probabilities are known.
+// Deletes the allocated token memory if final_pass is true.
+int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw,
+                  const uint8_t* const probas, int final_pass);
+
+// record the coding of coefficients without knowing the probabilities yet
+int VP8RecordCoeffTokens(int ctx, int coeff_type, int first, int last,
+                         const int16_t* const coeffs,
+                         VP8TBuffer* const tokens);
+
+// Estimate the final coded size given a set of 'probas'.
+size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas);
+
+// unused for now
+void VP8TokenToStats(const VP8TBuffer* const b, proba_t* const stats);
+
+#endif  // !DISABLE_TOKEN_BUFFER
+
+//------------------------------------------------------------------------------
+// VP8Encoder
+
+struct VP8Encoder {
+  const WebPConfig* config_;    // user configuration and parameters
+  WebPPicture* pic_;            // input / output picture
+
+  // headers
+  VP8FilterHeader   filter_hdr_;     // filtering information
+  VP8SegmentHeader  segment_hdr_;    // segment information
+
+  int profile_;                      // VP8's profile, deduced from Config.
+
+  // dimension, in macroblock units.
+  int mb_w_, mb_h_;
+  int preds_w_;   // stride of the *preds_ prediction plane (=4*mb_w + 1)
+
+  // number of partitions (1, 2, 4 or 8 = MAX_NUM_PARTITIONS)
+  int num_parts_;
+
+  // per-partition boolean decoders.
+  VP8BitWriter bw_;                         // part0
+  VP8BitWriter parts_[MAX_NUM_PARTITIONS];  // token partitions
+  VP8TBuffer tokens_;                       // token buffer
+
+  int percent_;                             // for progress
+
+  // transparency blob
+  int has_alpha_;
+  uint8_t* alpha_data_;       // non-NULL if transparency is present
+  uint32_t alpha_data_size_;
+  WebPWorker alpha_worker_;
+
+  // enhancement layer
+  int use_layer_;
+  VP8BitWriter layer_bw_;
+  uint8_t* layer_data_;
+  size_t layer_data_size_;
+
+  // quantization info (one set of DC/AC dequant factor per segment)
+  VP8SegmentInfo dqm_[NUM_MB_SEGMENTS];
+  int base_quant_;                 // nominal quantizer value. Only used
+                                   // for relative coding of segments' quant.
+  int alpha_;                      // global susceptibility (<=> complexity)
+  int uv_alpha_;                   // U/V quantization susceptibility
+  // global offset of quantizers, shared by all segments
+  int dq_y1_dc_;
+  int dq_y2_dc_, dq_y2_ac_;
+  int dq_uv_dc_, dq_uv_ac_;
+
+  // probabilities and statistics
+  VP8Proba proba_;
+  uint64_t sse_[4];        // sum of Y/U/V/A squared errors for all macroblocks
+  uint64_t sse_count_;     // pixel count for the sse_[] stats
+  int      coded_size_;
+  int      residual_bytes_[3][4];
+  int      block_count_[3];
+
+  // quality/speed settings
+  int method_;               // 0=fastest, 6=best/slowest.
+  VP8RDLevel rd_opt_level_;  // Deduced from method_.
+  int max_i4_header_bits_;   // partition #0 safeness factor
+  int thread_level_;         // derived from config->thread_level
+  int do_search_;            // derived from config->target_XXX
+  int use_tokens_;           // if true, use token buffer
+
+  // Memory
+  VP8MBInfo* mb_info_;   // contextual macroblock infos (mb_w_ + 1)
+  uint8_t*   preds_;     // predictions modes: (4*mb_w+1) * (4*mb_h+1)
+  uint32_t*  nz_;        // non-zero bit context: mb_w+1
+  uint8_t   *y_top_;     // top luma samples.
+  uint8_t   *uv_top_;    // top u/v samples.
+                         // U and V are packed into 16 bytes (8 U + 8 V)
+  LFStats   *lf_stats_;  // autofilter stats (if NULL, autofilter is off)
+};
+
+//------------------------------------------------------------------------------
+// internal functions. Not public.
+
+  // in tree.c
+extern const uint8_t VP8CoeffsProba0[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS];
+extern const uint8_t
+    VP8CoeffsUpdateProba[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS];
+// Reset the token probabilities to their initial (default) values
+void VP8DefaultProbas(VP8Encoder* const enc);
+// Write the token probabilities
+void VP8WriteProbas(VP8BitWriter* const bw, const VP8Proba* const probas);
+// Writes the partition #0 modes (that is: all intra modes)
+void VP8CodeIntraModes(VP8Encoder* const enc);
+
+  // in syntax.c
+// Generates the final bitstream by coding the partition0 and headers,
+// and appending an assembly of all the pre-coded token partitions.
+// Return true if everything is ok.
+int VP8EncWrite(VP8Encoder* const enc);
+// Release memory allocated for bit-writing in VP8EncLoop & seq.
+void VP8EncFreeBitWriters(VP8Encoder* const enc);
+
+  // in frame.c
+extern const uint8_t VP8EncBands[16 + 1];
+extern const uint8_t VP8Cat3[];
+extern const uint8_t VP8Cat4[];
+extern const uint8_t VP8Cat5[];
+extern const uint8_t VP8Cat6[];
+
+// Form all the four Intra16x16 predictions in the yuv_p_ cache
+void VP8MakeLuma16Preds(const VP8EncIterator* const it);
+// Form all the four Chroma8x8 predictions in the yuv_p_ cache
+void VP8MakeChroma8Preds(const VP8EncIterator* const it);
+// Form all the ten Intra4x4 predictions in the yuv_p_ cache
+// for the 4x4 block it->i4_
+void VP8MakeIntra4Preds(const VP8EncIterator* const it);
+// Rate calculation
+int VP8GetCostLuma16(VP8EncIterator* const it, const VP8ModeScore* const rd);
+int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]);
+int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd);
+// Main coding calls
+int VP8EncLoop(VP8Encoder* const enc);
+int VP8EncTokenLoop(VP8Encoder* const enc);
+
+  // in webpenc.c
+// Assign an error code to a picture. Return false for convenience.
+int WebPEncodingSetError(const WebPPicture* const pic, WebPEncodingError error);
+int WebPReportProgress(const WebPPicture* const pic,
+                       int percent, int* const percent_store);
+
+  // in analysis.c
+// Main analysis loop. Decides the segmentations and complexity.
+// Assigns a first guess for Intra16 and uvmode_ prediction modes.
+int VP8EncAnalyze(VP8Encoder* const enc);
+
+  // in quant.c
+// Sets up segment's quantization values, base_quant_ and filter strengths.
+void VP8SetSegmentParams(VP8Encoder* const enc, float quality);
+// Pick best modes and fills the levels. Returns true if skipped.
+int VP8Decimate(VP8EncIterator* const it, VP8ModeScore* const rd,
+                VP8RDLevel rd_opt);
+
+  // in alpha.c
+void VP8EncInitAlpha(VP8Encoder* const enc);    // initialize alpha compression
+int VP8EncStartAlpha(VP8Encoder* const enc);    // start alpha coding process
+int VP8EncFinishAlpha(VP8Encoder* const enc);   // finalize compressed data
+int VP8EncDeleteAlpha(VP8Encoder* const enc);   // delete compressed data
+
+  // in layer.c
+void VP8EncInitLayer(VP8Encoder* const enc);     // init everything
+void VP8EncCodeLayerBlock(VP8EncIterator* it);   // code one more macroblock
+int VP8EncFinishLayer(VP8Encoder* const enc);    // finalize coding
+void VP8EncDeleteLayer(VP8Encoder* enc);         // reclaim memory
+
+  // in filter.c
+
+// SSIM utils
+typedef struct {
+  double w, xm, ym, xxm, xym, yym;
+} DistoStats;
+void VP8SSIMAddStats(const DistoStats* const src, DistoStats* const dst);
+void VP8SSIMAccumulatePlane(const uint8_t* src1, int stride1,
+                            const uint8_t* src2, int stride2,
+                            int W, int H, DistoStats* const stats);
+double VP8SSIMGet(const DistoStats* const stats);
+double VP8SSIMGetSquaredError(const DistoStats* const stats);
+
+// autofilter
+void VP8InitFilter(VP8EncIterator* const it);
+void VP8StoreFilterStats(VP8EncIterator* const it);
+void VP8AdjustFilterStrength(VP8EncIterator* const it);
+
+// returns the approximate filtering strength needed to smooth a edge
+// step of 'delta', given a sharpness parameter 'sharpness'.
+int VP8FilterStrengthFromDelta(int sharpness, int delta);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  /* WEBP_ENC_VP8ENCI_H_ */