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// Copyright 2012 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.
// -----------------------------------------------------------------------------
//
// Lossless encoder: internal header.
//
// Author: Vikas Arora (vikaas.arora@gmail.com)
#ifndef WEBP_ENC_VP8LI_ENC_H_
#define WEBP_ENC_VP8LI_ENC_H_
#ifdef HAVE_CONFIG_H
#include "src/webp/config.h"
#endif
// Either WEBP_NEAR_LOSSLESS is defined as 0 in config.h when compiling to
// disable near-lossless, or it is enabled by default.
#ifndef WEBP_NEAR_LOSSLESS
#define WEBP_NEAR_LOSSLESS 1
#endif
#include "src/enc/backward_references_enc.h"
#include "src/enc/histogram_enc.h"
#include "src/utils/bit_writer_utils.h"
#include "src/webp/encode.h"
#include "src/webp/format_constants.h"
#ifdef __cplusplus
extern "C" {
#endif
// maximum value of transform_bits_ in VP8LEncoder.
#define MAX_TRANSFORM_BITS 6
typedef enum {
kEncoderNone = 0,
kEncoderARGB,
kEncoderNearLossless,
kEncoderPalette
} VP8LEncoderARGBContent;
typedef struct {
const WebPConfig* config_; // user configuration and parameters
const WebPPicture* pic_; // input picture.
uint32_t* argb_; // Transformed argb image data.
VP8LEncoderARGBContent argb_content_; // Content type of the argb buffer.
uint32_t* argb_scratch_; // Scratch memory for argb rows
// (used for prediction).
uint32_t* transform_data_; // Scratch memory for transform data.
uint32_t* transform_mem_; // Currently allocated memory.
size_t transform_mem_size_; // Currently allocated memory size.
int current_width_; // Corresponds to packed image width.
// Encoding parameters derived from quality parameter.
int histo_bits_;
int transform_bits_; // <= MAX_TRANSFORM_BITS.
int cache_bits_; // If equal to 0, don't use color cache.
// Encoding parameters derived from image characteristics.
int use_cross_color_;
int use_subtract_green_;
int use_predict_;
int use_palette_;
int palette_size_;
uint32_t palette_[MAX_PALETTE_SIZE];
// Sorted version of palette_ for cache purposes.
uint32_t palette_sorted_[MAX_PALETTE_SIZE];
// Some 'scratch' (potentially large) objects.
struct VP8LBackwardRefs refs_[4]; // Backward Refs array for temporaries.
VP8LHashChain hash_chain_; // HashChain data for constructing
// backward references.
} VP8LEncoder;
//------------------------------------------------------------------------------
// internal functions. Not public.
// Encodes the picture.
// Returns 0 if config or picture is NULL or picture doesn't have valid argb
// input.
int VP8LEncodeImage(const WebPConfig* const config,
const WebPPicture* const picture);
// Encodes the main image stream using the supplied bit writer.
// If 'use_cache' is false, disables the use of color cache.
WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
const WebPPicture* const picture,
VP8LBitWriter* const bw, int use_cache);
#if (WEBP_NEAR_LOSSLESS == 1)
// in near_lossless.c
// Near lossless preprocessing in RGB color-space.
int VP8ApplyNearLossless(const WebPPicture* const picture, int quality,
uint32_t* const argb_dst);
#endif
//------------------------------------------------------------------------------
// Image transforms in predictor.c.
void VP8LResidualImage(int width, int height, int bits, int low_effort,
uint32_t* const argb, uint32_t* const argb_scratch,
uint32_t* const image, int near_lossless, int exact,
int used_subtract_green);
void VP8LColorSpaceTransform(int width, int height, int bits, int quality,
uint32_t* const argb, uint32_t* image);
//------------------------------------------------------------------------------
#ifdef __cplusplus
} // extern "C"
#endif
#endif // WEBP_ENC_VP8LI_ENC_H_