1// Copyright 2012 Google Inc. All Rights Reserved.
2//
3// Use of this source code is governed by a BSD-style license
4// that can be found in the COPYING file in the root of the source
5// tree. An additional intellectual property rights grant can be found
6// in the file PATENTS. All contributing project authors may
7// be found in the AUTHORS file in the root of the source tree.
8// -----------------------------------------------------------------------------
9//
10// Lossless encoder: internal header.
11//
12// Author: Vikas Arora (vikaas.arora@gmail.com)
13
14#ifndef WEBP_ENC_VP8LI_H_
15#define WEBP_ENC_VP8LI_H_
16
17#include "./backward_references_enc.h"
18#include "./histogram_enc.h"
19#include "../utils/bit_writer_utils.h"
20#include "../webp/encode.h"
21#include "../webp/format_constants.h"
22
23#ifdef __cplusplus
24extern "C" {
25#endif
26
27// maximum value of transform_bits_ in VP8LEncoder.
28#define MAX_TRANSFORM_BITS 6
29
30typedef struct {
31 const WebPConfig* config_; // user configuration and parameters
32 const WebPPicture* pic_; // input picture.
33
34 uint32_t* argb_; // Transformed argb image data.
35 uint32_t* argb_scratch_; // Scratch memory for argb rows
36 // (used for prediction).
37 uint32_t* transform_data_; // Scratch memory for transform data.
38 uint32_t* transform_mem_; // Currently allocated memory.
39 size_t transform_mem_size_; // Currently allocated memory size.
40
41 int current_width_; // Corresponds to packed image width.
42
43 // Encoding parameters derived from quality parameter.
44 int histo_bits_;
45 int transform_bits_; // <= MAX_TRANSFORM_BITS.
46 int cache_bits_; // If equal to 0, don't use color cache.
47
48 // Encoding parameters derived from image characteristics.
49 int use_cross_color_;
50 int use_subtract_green_;
51 int use_predict_;
52 int use_palette_;
53 int palette_size_;
54 uint32_t palette_[MAX_PALETTE_SIZE];
55
56 // Some 'scratch' (potentially large) objects.
57 struct VP8LBackwardRefs refs_[2]; // Backward Refs array corresponding to
58 // LZ77 & RLE coding.
59 VP8LHashChain hash_chain_; // HashChain data for constructing
60 // backward references.
61} VP8LEncoder;
62
63//------------------------------------------------------------------------------
64// internal functions. Not public.
65
66// Encodes the picture.
67// Returns 0 if config or picture is NULL or picture doesn't have valid argb
68// input.
69int VP8LEncodeImage(const WebPConfig* const config,
70 const WebPPicture* const picture);
71
72// Encodes the main image stream using the supplied bit writer.
73// If 'use_cache' is false, disables the use of color cache.
74WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
75 const WebPPicture* const picture,
76 VP8LBitWriter* const bw, int use_cache);
77
78//------------------------------------------------------------------------------
79// Image transforms in predictor.c.
80
81void VP8LResidualImage(int width, int height, int bits, int low_effort,
82 uint32_t* const argb, uint32_t* const argb_scratch,
83 uint32_t* const image, int near_lossless, int exact,
84 int used_subtract_green);
85
86void VP8LColorSpaceTransform(int width, int height, int bits, int quality,
87 uint32_t* const argb, uint32_t* image);
88
89//------------------------------------------------------------------------------
90
91#ifdef __cplusplus
92} // extern "C"
93#endif
94
95#endif /* WEBP_ENC_VP8LI_H_ */
96