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