1// Copyright 2011 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// Internal header for mux library.
11//
12// Author: Urvang (urvang@google.com)
13
14#ifndef WEBP_MUX_MUXI_H_
15#define WEBP_MUX_MUXI_H_
16
17#include <assert.h>
18#include <stdlib.h>
19#include "src/dec/vp8i_dec.h"
20#include "src/dec/vp8li_dec.h"
21#include "src/webp/mux.h"
22
23#ifdef __cplusplus
24extern "C" {
25#endif
26
27//------------------------------------------------------------------------------
28// Defines and constants.
29
30#define MUX_MAJ_VERSION 1
31#define MUX_MIN_VERSION 1
32#define MUX_REV_VERSION 0
33
34// Chunk object.
35typedef struct WebPChunk WebPChunk;
36struct WebPChunk {
37 uint32_t tag_;
38 int owner_; // True if *data_ memory is owned internally.
39 // VP8X, ANIM, and other internally created chunks
40 // like ANMF are always owned.
41 WebPData data_;
42 WebPChunk* next_;
43};
44
45// MuxImage object. Store a full WebP image (including ANMF chunk, ALPH
46// chunk and VP8/VP8L chunk),
47typedef struct WebPMuxImage WebPMuxImage;
48struct WebPMuxImage {
49 WebPChunk* header_; // Corresponds to WEBP_CHUNK_ANMF.
50 WebPChunk* alpha_; // Corresponds to WEBP_CHUNK_ALPHA.
51 WebPChunk* img_; // Corresponds to WEBP_CHUNK_IMAGE.
52 WebPChunk* unknown_; // Corresponds to WEBP_CHUNK_UNKNOWN.
53 int width_;
54 int height_;
55 int has_alpha_; // Through ALPH chunk or as part of VP8L.
56 int is_partial_; // True if only some of the chunks are filled.
57 WebPMuxImage* next_;
58};
59
60// Main mux object. Stores data chunks.
61struct WebPMux {
62 WebPMuxImage* images_;
63 WebPChunk* iccp_;
64 WebPChunk* exif_;
65 WebPChunk* xmp_;
66 WebPChunk* anim_;
67 WebPChunk* vp8x_;
68
69 WebPChunk* unknown_;
70 int canvas_width_;
71 int canvas_height_;
72};
73
74// CHUNK_INDEX enum: used for indexing within 'kChunks' (defined below) only.
75// Note: the reason for having two enums ('WebPChunkId' and 'CHUNK_INDEX') is to
76// allow two different chunks to have the same id (e.g. WebPChunkId
77// 'WEBP_CHUNK_IMAGE' can correspond to CHUNK_INDEX 'IDX_VP8' or 'IDX_VP8L').
78typedef enum {
79 IDX_VP8X = 0,
80 IDX_ICCP,
81 IDX_ANIM,
82 IDX_ANMF,
83 IDX_ALPHA,
84 IDX_VP8,
85 IDX_VP8L,
86 IDX_EXIF,
87 IDX_XMP,
88 IDX_UNKNOWN,
89
90 IDX_NIL,
91 IDX_LAST_CHUNK
92} CHUNK_INDEX;
93
94#define NIL_TAG 0x00000000u // To signal void chunk.
95
96typedef struct {
97 uint32_t tag;
98 WebPChunkId id;
99 uint32_t size;
100} ChunkInfo;
101
102extern const ChunkInfo kChunks[IDX_LAST_CHUNK];
103
104//------------------------------------------------------------------------------
105// Chunk object management.
106
107// Initialize.
108void ChunkInit(WebPChunk* const chunk);
109
110// Get chunk index from chunk tag. Returns IDX_UNKNOWN if not found.
111CHUNK_INDEX ChunkGetIndexFromTag(uint32_t tag);
112
113// Get chunk id from chunk tag. Returns WEBP_CHUNK_UNKNOWN if not found.
114WebPChunkId ChunkGetIdFromTag(uint32_t tag);
115
116// Convert a fourcc string to a tag.
117uint32_t ChunkGetTagFromFourCC(const char fourcc[4]);
118
119// Get chunk index from fourcc. Returns IDX_UNKNOWN if given fourcc is unknown.
120CHUNK_INDEX ChunkGetIndexFromFourCC(const char fourcc[4]);
121
122// Search for nth chunk with given 'tag' in the chunk list.
123// nth = 0 means "last of the list".
124WebPChunk* ChunkSearchList(WebPChunk* first, uint32_t nth, uint32_t tag);
125
126// Fill the chunk with the given data.
127WebPMuxError ChunkAssignData(WebPChunk* chunk, const WebPData* const data,
128 int copy_data, uint32_t tag);
129
130// Sets 'chunk' as the only element in 'chunk_list' if it is empty.
131// On success ownership is transferred from 'chunk' to the 'chunk_list'.
132WebPMuxError ChunkSetHead(WebPChunk* const chunk, WebPChunk** const chunk_list);
133// Sets 'chunk' at last position in the 'chunk_list'.
134// On success ownership is transferred from 'chunk' to the 'chunk_list'.
135// *chunk_list also points towards the last valid element of the initial
136// *chunk_list.
137WebPMuxError ChunkAppend(WebPChunk* const chunk, WebPChunk*** const chunk_list);
138
139// Releases chunk and returns chunk->next_.
140WebPChunk* ChunkRelease(WebPChunk* const chunk);
141
142// Deletes given chunk & returns chunk->next_.
143WebPChunk* ChunkDelete(WebPChunk* const chunk);
144
145// Deletes all chunks in the given chunk list.
146void ChunkListDelete(WebPChunk** const chunk_list);
147
148// Returns size of the chunk including chunk header and padding byte (if any).
149static WEBP_INLINE size_t SizeWithPadding(size_t chunk_size) {
150 assert(chunk_size <= MAX_CHUNK_PAYLOAD);
151 return CHUNK_HEADER_SIZE + ((chunk_size + 1) & ~1U);
152}
153
154// Size of a chunk including header and padding.
155static WEBP_INLINE size_t ChunkDiskSize(const WebPChunk* chunk) {
156 const size_t data_size = chunk->data_.size;
157 return SizeWithPadding(data_size);
158}
159
160// Total size of a list of chunks.
161size_t ChunkListDiskSize(const WebPChunk* chunk_list);
162
163// Write out the given list of chunks into 'dst'.
164uint8_t* ChunkListEmit(const WebPChunk* chunk_list, uint8_t* dst);
165
166//------------------------------------------------------------------------------
167// MuxImage object management.
168
169// Initialize.
170void MuxImageInit(WebPMuxImage* const wpi);
171
172// Releases image 'wpi' and returns wpi->next.
173WebPMuxImage* MuxImageRelease(WebPMuxImage* const wpi);
174
175// Delete image 'wpi' and return the next image in the list or NULL.
176// 'wpi' can be NULL.
177WebPMuxImage* MuxImageDelete(WebPMuxImage* const wpi);
178
179// Count number of images matching the given tag id in the 'wpi_list'.
180// If id == WEBP_CHUNK_NIL, all images will be matched.
181int MuxImageCount(const WebPMuxImage* wpi_list, WebPChunkId id);
182
183// Update width/height/has_alpha info from chunks within wpi.
184// Also remove ALPH chunk if not needed.
185int MuxImageFinalize(WebPMuxImage* const wpi);
186
187// Check if given ID corresponds to an image related chunk.
188static WEBP_INLINE int IsWPI(WebPChunkId id) {
189 switch (id) {
190 case WEBP_CHUNK_ANMF:
191 case WEBP_CHUNK_ALPHA:
192 case WEBP_CHUNK_IMAGE: return 1;
193 default: return 0;
194 }
195}
196
197// Pushes 'wpi' at the end of 'wpi_list'.
198WebPMuxError MuxImagePush(const WebPMuxImage* wpi, WebPMuxImage** wpi_list);
199
200// Delete nth image in the image list.
201WebPMuxError MuxImageDeleteNth(WebPMuxImage** wpi_list, uint32_t nth);
202
203// Get nth image in the image list.
204WebPMuxError MuxImageGetNth(const WebPMuxImage** wpi_list, uint32_t nth,
205 WebPMuxImage** wpi);
206
207// Total size of the given image.
208size_t MuxImageDiskSize(const WebPMuxImage* const wpi);
209
210// Write out the given image into 'dst'.
211uint8_t* MuxImageEmit(const WebPMuxImage* const wpi, uint8_t* dst);
212
213//------------------------------------------------------------------------------
214// Helper methods for mux.
215
216// Checks if the given image list contains at least one image with alpha.
217int MuxHasAlpha(const WebPMuxImage* images);
218
219// Write out RIFF header into 'data', given total data size 'size'.
220uint8_t* MuxEmitRiffHeader(uint8_t* const data, size_t size);
221
222// Returns the list where chunk with given ID is to be inserted in mux.
223WebPChunk** MuxGetChunkListFromId(const WebPMux* mux, WebPChunkId id);
224
225// Validates the given mux object.
226WebPMuxError MuxValidate(const WebPMux* const mux);
227
228//------------------------------------------------------------------------------
229
230#ifdef __cplusplus
231} // extern "C"
232#endif
233
234#endif // WEBP_MUX_MUXI_H_
235