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_ENC_H_ |
15 | #define WEBP_ENC_VP8LI_ENC_H_ |
16 | |
17 | #ifdef HAVE_CONFIG_H |
18 | #include "src/webp/config.h" |
19 | #endif |
20 | // Either WEBP_NEAR_LOSSLESS is defined as 0 in config.h when compiling to |
21 | // disable near-lossless, or it is enabled by default. |
22 | #ifndef WEBP_NEAR_LOSSLESS |
23 | #define WEBP_NEAR_LOSSLESS 1 |
24 | #endif |
25 | |
26 | #include "src/enc/backward_references_enc.h" |
27 | #include "src/enc/histogram_enc.h" |
28 | #include "src/utils/bit_writer_utils.h" |
29 | #include "src/webp/encode.h" |
30 | #include "src/webp/format_constants.h" |
31 | |
32 | #ifdef __cplusplus |
33 | extern "C" { |
34 | #endif |
35 | |
36 | // maximum value of transform_bits_ in VP8LEncoder. |
37 | #define MAX_TRANSFORM_BITS 6 |
38 | |
39 | typedef enum { |
40 | kEncoderNone = 0, |
41 | kEncoderARGB, |
42 | kEncoderNearLossless, |
43 | kEncoderPalette |
44 | } VP8LEncoderARGBContent; |
45 | |
46 | typedef struct { |
47 | const WebPConfig* config_; // user configuration and parameters |
48 | const WebPPicture* pic_; // input picture. |
49 | |
50 | uint32_t* argb_; // Transformed argb image data. |
51 | VP8LEncoderARGBContent argb_content_; // Content type of the argb buffer. |
52 | uint32_t* argb_scratch_; // Scratch memory for argb rows |
53 | // (used for prediction). |
54 | uint32_t* transform_data_; // Scratch memory for transform data. |
55 | uint32_t* transform_mem_; // Currently allocated memory. |
56 | size_t transform_mem_size_; // Currently allocated memory size. |
57 | |
58 | int current_width_; // Corresponds to packed image width. |
59 | |
60 | // Encoding parameters derived from quality parameter. |
61 | int histo_bits_; |
62 | int transform_bits_; // <= MAX_TRANSFORM_BITS. |
63 | int cache_bits_; // If equal to 0, don't use color cache. |
64 | |
65 | // Encoding parameters derived from image characteristics. |
66 | int use_cross_color_; |
67 | int use_subtract_green_; |
68 | int use_predict_; |
69 | int use_palette_; |
70 | int palette_size_; |
71 | uint32_t palette_[MAX_PALETTE_SIZE]; |
72 | |
73 | // Some 'scratch' (potentially large) objects. |
74 | struct VP8LBackwardRefs refs_[3]; // Backward Refs array for temporaries. |
75 | VP8LHashChain hash_chain_; // HashChain data for constructing |
76 | // backward references. |
77 | } VP8LEncoder; |
78 | |
79 | //------------------------------------------------------------------------------ |
80 | // internal functions. Not public. |
81 | |
82 | // Encodes the picture. |
83 | // Returns 0 if config or picture is NULL or picture doesn't have valid argb |
84 | // input. |
85 | int VP8LEncodeImage(const WebPConfig* const config, |
86 | const WebPPicture* const picture); |
87 | |
88 | // Encodes the main image stream using the supplied bit writer. |
89 | // If 'use_cache' is false, disables the use of color cache. |
90 | WebPEncodingError VP8LEncodeStream(const WebPConfig* const config, |
91 | const WebPPicture* const picture, |
92 | VP8LBitWriter* const bw, int use_cache); |
93 | |
94 | #if (WEBP_NEAR_LOSSLESS == 1) |
95 | // in near_lossless.c |
96 | // Near lossless preprocessing in RGB color-space. |
97 | int VP8ApplyNearLossless(const WebPPicture* const picture, int quality, |
98 | uint32_t* const argb_dst); |
99 | #endif |
100 | |
101 | //------------------------------------------------------------------------------ |
102 | // Image transforms in predictor.c. |
103 | |
104 | void VP8LResidualImage(int width, int height, int bits, int low_effort, |
105 | uint32_t* const argb, uint32_t* const argb_scratch, |
106 | uint32_t* const image, int near_lossless, int exact, |
107 | int used_subtract_green); |
108 | |
109 | void VP8LColorSpaceTransform(int width, int height, int bits, int quality, |
110 | uint32_t* const argb, uint32_t* image); |
111 | |
112 | //------------------------------------------------------------------------------ |
113 | |
114 | #ifdef __cplusplus |
115 | } // extern "C" |
116 | #endif |
117 | |
118 | #endif // WEBP_ENC_VP8LI_ENC_H_ |
119 | |