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.h"
19 #include "../dec/vp8li.h"
20 #include "../webp/mux.h"
21
22 #if defined(__cplusplus) || defined(c_plusplus)
23 extern "C" {
24 #endif
25
26 //------------------------------------------------------------------------------
27 // Defines and constants.
28
29 #define MUX_MAJ_VERSION 0
30 #define MUX_MIN_VERSION 1
31 #define MUX_REV_VERSION 1
32
33 // Chunk object.
34 typedef struct WebPChunk WebPChunk;
35 struct 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/FRGM are always owned.
40 WebPData data_;
41 WebPChunk* next_;
42 };
43
44 // MuxImage object. Store a full WebP image (including ANMF/FRGM chunk, ALPH
45 // chunk and VP8/VP8L chunk),
46 typedef struct WebPMuxImage WebPMuxImage;
47 struct WebPMuxImage {
48 WebPChunk* header_; // Corresponds to WEBP_CHUNK_ANMF/WEBP_CHUNK_FRGM.
49 WebPChunk* alpha_; // Corresponds to WEBP_CHUNK_ALPHA.
50 WebPChunk* img_; // Corresponds to WEBP_CHUNK_IMAGE.
51 int is_partial_; // True if only some of the chunks are filled.
52 WebPMuxImage* next_;
53 };
54
55 // Main mux object. Stores data chunks.
56 struct WebPMux {
57 WebPMuxImage* images_;
58 WebPChunk* iccp_;
59 WebPChunk* exif_;
60 WebPChunk* xmp_;
61 WebPChunk* anim_;
62 WebPChunk* vp8x_;
63
64 WebPChunk* unknown_;
65 };
66
67 // CHUNK_INDEX enum: used for indexing within 'kChunks' (defined below) only.
68 // Note: the reason for having two enums ('WebPChunkId' and 'CHUNK_INDEX') is to
69 // allow two different chunks to have the same id (e.g. WebPChunkId
70 // 'WEBP_CHUNK_IMAGE' can correspond to CHUNK_INDEX 'IDX_VP8' or 'IDX_VP8L').
71 typedef enum {
72 IDX_VP8X = 0,
73 IDX_ICCP,
74 IDX_ANIM,
75 IDX_ANMF,
76 IDX_FRGM,
77 IDX_ALPHA,
78 IDX_VP8,
79 IDX_VP8L,
80 IDX_EXIF,
81 IDX_XMP,
82 IDX_UNKNOWN,
83
84 IDX_NIL,
85 IDX_LAST_CHUNK
86 } CHUNK_INDEX;
87
88 #define NIL_TAG 0x00000000u // To signal void chunk.
89
90 typedef struct {
91 uint32_t tag;
92 WebPChunkId id;
93 uint32_t size;
94 } ChunkInfo;
95
96 extern const ChunkInfo kChunks[IDX_LAST_CHUNK];
97
98 //------------------------------------------------------------------------------
99 // Chunk object management.
100
101 // Initialize.
102 void ChunkInit(WebPChunk* const chunk);
103
104 // Get chunk index from chunk tag. Returns IDX_NIL if not found.
105 CHUNK_INDEX ChunkGetIndexFromTag(uint32_t tag);
106
107 // Get chunk id from chunk tag. Returns WEBP_CHUNK_NIL if not found.
108 WebPChunkId ChunkGetIdFromTag(uint32_t tag);
109
110 // Convert a fourcc string to a tag.
111 uint32_t ChunkGetTagFromFourCC(const char fourcc[4]);
112
113 // Get chunk index from fourcc. Returns IDX_UNKNOWN if given fourcc is unknown.
114 CHUNK_INDEX ChunkGetIndexFromFourCC(const char fourcc[4]);
115
116 // Search for nth chunk with given 'tag' in the chunk list.
117 // nth = 0 means "last of the list".
118 WebPChunk* ChunkSearchList(WebPChunk* first, uint32_t nth, uint32_t tag);
119
120 // Fill the chunk with the given data.
121 WebPMuxError ChunkAssignData(WebPChunk* chunk, const WebPData* const data,
122 int copy_data, uint32_t tag);
123
124 // Sets 'chunk' at nth position in the 'chunk_list'.
125 // nth = 0 has the special meaning "last of the list".
126 // On success ownership is transferred from 'chunk' to the 'chunk_list'.
127 WebPMuxError ChunkSetNth(WebPChunk* chunk, WebPChunk** chunk_list,
128 uint32_t nth);
129
130 // Releases chunk and returns chunk->next_.
131 WebPChunk* ChunkRelease(WebPChunk* const chunk);
132
133 // Deletes given chunk & returns chunk->next_.
134 WebPChunk* ChunkDelete(WebPChunk* const chunk);
135
136 // Returns size of the chunk including chunk header and padding byte (if any).
SizeWithPadding(size_t chunk_size)137 static WEBP_INLINE size_t SizeWithPadding(size_t chunk_size) {
138 return CHUNK_HEADER_SIZE + ((chunk_size + 1) & ~1U);
139 }
140
141 // Size of a chunk including header and padding.
ChunkDiskSize(const WebPChunk * chunk)142 static WEBP_INLINE size_t ChunkDiskSize(const WebPChunk* chunk) {
143 const size_t data_size = chunk->data_.size;
144 assert(data_size < MAX_CHUNK_PAYLOAD);
145 return SizeWithPadding(data_size);
146 }
147
148 // Total size of a list of chunks.
149 size_t ChunksListDiskSize(const WebPChunk* chunk_list);
150
151 // Write out the given list of chunks into 'dst'.
152 uint8_t* ChunkListEmit(const WebPChunk* chunk_list, uint8_t* dst);
153
154 // Get the width & height of image stored in 'image_chunk'.
155 WebPMuxError MuxGetImageWidthHeight(const WebPChunk* const image_chunk,
156 int* const width, int* const height);
157
158 //------------------------------------------------------------------------------
159 // MuxImage object management.
160
161 // Initialize.
162 void MuxImageInit(WebPMuxImage* const wpi);
163
164 // Releases image 'wpi' and returns wpi->next.
165 WebPMuxImage* MuxImageRelease(WebPMuxImage* const wpi);
166
167 // Delete image 'wpi' and return the next image in the list or NULL.
168 // 'wpi' can be NULL.
169 WebPMuxImage* MuxImageDelete(WebPMuxImage* const wpi);
170
171 // Delete all images in 'wpi_list'.
172 void MuxImageDeleteAll(WebPMuxImage** const wpi_list);
173
174 // Count number of images matching the given tag id in the 'wpi_list'.
175 // If id == WEBP_CHUNK_NIL, all images will be matched.
176 int MuxImageCount(const WebPMuxImage* wpi_list, WebPChunkId id);
177
178 // Check if given ID corresponds to an image related chunk.
IsWPI(WebPChunkId id)179 static WEBP_INLINE int IsWPI(WebPChunkId id) {
180 switch (id) {
181 case WEBP_CHUNK_ANMF:
182 case WEBP_CHUNK_FRGM:
183 case WEBP_CHUNK_ALPHA:
184 case WEBP_CHUNK_IMAGE: return 1;
185 default: return 0;
186 }
187 }
188
189 // Get a reference to appropriate chunk list within an image given chunk tag.
MuxImageGetListFromId(const WebPMuxImage * const wpi,WebPChunkId id)190 static WEBP_INLINE WebPChunk** MuxImageGetListFromId(
191 const WebPMuxImage* const wpi, WebPChunkId id) {
192 assert(wpi != NULL);
193 switch (id) {
194 case WEBP_CHUNK_ANMF:
195 case WEBP_CHUNK_FRGM: return (WebPChunk**)&wpi->header_;
196 case WEBP_CHUNK_ALPHA: return (WebPChunk**)&wpi->alpha_;
197 case WEBP_CHUNK_IMAGE: return (WebPChunk**)&wpi->img_;
198 default: return NULL;
199 }
200 }
201
202 // Pushes 'wpi' at the end of 'wpi_list'.
203 WebPMuxError MuxImagePush(const WebPMuxImage* wpi, WebPMuxImage** wpi_list);
204
205 // Delete nth image in the image list.
206 WebPMuxError MuxImageDeleteNth(WebPMuxImage** wpi_list, uint32_t nth);
207
208 // Get nth image in the image list.
209 WebPMuxError MuxImageGetNth(const WebPMuxImage** wpi_list, uint32_t nth,
210 WebPMuxImage** wpi);
211
212 // Total size of the given image.
213 size_t MuxImageDiskSize(const WebPMuxImage* const wpi);
214
215 // Total size of a list of images.
216 size_t MuxImageListDiskSize(const WebPMuxImage* wpi_list);
217
218 // Write out the given image into 'dst'.
219 uint8_t* MuxImageEmit(const WebPMuxImage* const wpi, uint8_t* dst);
220
221 // Write out the given list of images into 'dst'.
222 uint8_t* MuxImageListEmit(const WebPMuxImage* wpi_list, uint8_t* dst);
223
224 //------------------------------------------------------------------------------
225 // Helper methods for mux.
226
227 // Checks if the given image list contains at least one lossless image.
228 int MuxHasLosslessImages(const WebPMuxImage* images);
229
230 // Write out RIFF header into 'data', given total data size 'size'.
231 uint8_t* MuxEmitRiffHeader(uint8_t* const data, size_t size);
232
233 // Returns the list where chunk with given ID is to be inserted in mux.
234 // Return value is NULL if this chunk should be inserted in mux->images_ list
235 // or if 'id' is not known.
236 WebPChunk** MuxGetChunkListFromId(const WebPMux* mux, WebPChunkId id);
237
238 // Validates that the given mux has a single image.
239 WebPMuxError MuxValidateForImage(const WebPMux* const mux);
240
241 // Validates the given mux object.
242 WebPMuxError MuxValidate(const WebPMux* const mux);
243
244 //------------------------------------------------------------------------------
245
246 #if defined(__cplusplus) || defined(c_plusplus)
247 } // extern "C"
248 #endif
249
250 #endif /* WEBP_MUX_MUXI_H_ */
251