Coverage Report

Created: 2025-07-23 08:18

/src/libwebp/src/mux/muxedit.c
Line
Count
Source (jump to first uncovered line)
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
// Set and delete APIs for mux.
11
//
12
// Authors: Urvang (urvang@google.com)
13
//          Vikas (vikasa@google.com)
14
15
#include <assert.h>
16
#include <stddef.h>
17
#include <string.h>
18
19
#include "src/dec/vp8_dec.h"
20
#include "src/mux/muxi.h"
21
#include "src/utils/utils.h"
22
#include "src/webp/format_constants.h"
23
#include "src/webp/mux.h"
24
#include "src/webp/mux_types.h"
25
#include "src/webp/types.h"
26
27
//------------------------------------------------------------------------------
28
// Life of a mux object.
29
30
668
static void MuxInit(WebPMux* const mux) {
31
668
  assert(mux != NULL);
32
668
  memset(mux, 0, sizeof(*mux));
33
668
  mux->canvas_width = 0;     // just to be explicit
34
668
  mux->canvas_height = 0;
35
668
}
36
37
668
WebPMux* WebPNewInternal(int version) {
38
668
  if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_MUX_ABI_VERSION)) {
39
0
    return NULL;
40
668
  } else {
41
668
    WebPMux* const mux = (WebPMux*)WebPSafeMalloc(1ULL, sizeof(WebPMux));
42
668
    if (mux != NULL) MuxInit(mux);
43
668
    return mux;
44
668
  }
45
668
}
46
47
// Delete all images in 'wpi_list'.
48
668
static void DeleteAllImages(WebPMuxImage** const wpi_list) {
49
1.16k
  while (*wpi_list != NULL) {
50
498
    *wpi_list = MuxImageDelete(*wpi_list);
51
498
  }
52
668
}
53
54
668
static void MuxRelease(WebPMux* const mux) {
55
668
  assert(mux != NULL);
56
668
  DeleteAllImages(&mux->images);
57
668
  ChunkListDelete(&mux->vp8x);
58
668
  ChunkListDelete(&mux->iccp);
59
668
  ChunkListDelete(&mux->anim);
60
668
  ChunkListDelete(&mux->exif);
61
668
  ChunkListDelete(&mux->xmp);
62
668
  ChunkListDelete(&mux->unknown);
63
668
}
64
65
3.20k
void WebPMuxDelete(WebPMux* mux) {
66
3.20k
  if (mux != NULL) {
67
668
    MuxRelease(mux);
68
668
    WebPSafeFree(mux);
69
668
  }
70
3.20k
}
71
72
//------------------------------------------------------------------------------
73
// Helper method(s).
74
75
// Handy MACRO, makes MuxSet() very symmetric to MuxGet().
76
#define SWITCH_ID_LIST(INDEX, LIST)                                            \
77
128
  do {                                                                         \
78
128
    if (idx == (INDEX)) {                                                      \
79
52
      err = ChunkAssignData(&chunk, data, copy_data, tag);                     \
80
52
      if (err == WEBP_MUX_OK) {                                                \
81
52
        err = ChunkSetHead(&chunk, (LIST));                                    \
82
52
        if (err != WEBP_MUX_OK) ChunkRelease(&chunk);                          \
83
52
      }                                                                        \
84
52
      return err;                                                              \
85
52
    }                                                                          \
86
128
  } while (0)
87
88
static WebPMuxError MuxSet(WebPMux* const mux, uint32_t tag,
89
52
                           const WebPData* const data, int copy_data) {
90
52
  WebPChunk chunk;
91
52
  WebPMuxError err = WEBP_MUX_NOT_FOUND;
92
52
  const CHUNK_INDEX idx = ChunkGetIndexFromTag(tag);
93
52
  assert(mux != NULL);
94
52
  assert(!IsWPI(kChunks[idx].id));
95
96
52
  ChunkInit(&chunk);
97
52
  SWITCH_ID_LIST(IDX_VP8X,    &mux->vp8x);
98
26
  SWITCH_ID_LIST(IDX_ICCP,    &mux->iccp);
99
25
  SWITCH_ID_LIST(IDX_ANIM,    &mux->anim);
100
25
  SWITCH_ID_LIST(IDX_EXIF,    &mux->exif);
101
0
  SWITCH_ID_LIST(IDX_XMP,     &mux->xmp);
102
0
  SWITCH_ID_LIST(IDX_UNKNOWN, &mux->unknown);
103
0
  return err;
104
0
}
105
#undef SWITCH_ID_LIST
106
107
// Create data for frame given image data, offsets and duration.
108
static WebPMuxError CreateFrameData(
109
    int width, int height, const WebPMuxFrameInfo* const info,
110
0
    WebPData* const frame) {
111
0
  uint8_t* frame_bytes;
112
0
  const size_t frame_size = kChunks[IDX_ANMF].size;
113
114
0
  assert(width > 0 && height > 0 && info->duration >= 0);
115
0
  assert(info->dispose_method == (info->dispose_method & 1));
116
  // Note: assertion on upper bounds is done in PutLE24().
117
118
0
  frame_bytes = (uint8_t*)WebPSafeMalloc(1ULL, frame_size);
119
0
  if (frame_bytes == NULL) return WEBP_MUX_MEMORY_ERROR;
120
121
0
  PutLE24(frame_bytes + 0, info->x_offset / 2);
122
0
  PutLE24(frame_bytes + 3, info->y_offset / 2);
123
124
0
  PutLE24(frame_bytes + 6, width - 1);
125
0
  PutLE24(frame_bytes + 9, height - 1);
126
0
  PutLE24(frame_bytes + 12, info->duration);
127
0
  frame_bytes[15] =
128
0
      (info->blend_method == WEBP_MUX_NO_BLEND ? 2 : 0) |
129
0
      (info->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND ? 1 : 0);
130
131
0
  frame->bytes = frame_bytes;
132
0
  frame->size = frame_size;
133
0
  return WEBP_MUX_OK;
134
0
}
135
136
// Outputs image data given a bitstream. The bitstream can either be a
137
// single-image WebP file or raw VP8/VP8L data.
138
// Also outputs 'is_lossless' to be true if the given bitstream is lossless.
139
static WebPMuxError GetImageData(const WebPData* const bitstream,
140
                                 WebPData* const image, WebPData* const alpha,
141
26
                                 int* const is_lossless) {
142
26
  WebPDataInit(alpha);  // Default: no alpha.
143
26
  if (bitstream->size < TAG_SIZE ||
144
26
      memcmp(bitstream->bytes, "RIFF", TAG_SIZE)) {
145
    // It is NOT webp file data. Return input data as is.
146
0
    *image = *bitstream;
147
26
  } else {
148
    // It is webp file data. Extract image data from it.
149
26
    const WebPMuxImage* wpi;
150
26
    WebPMux* const mux = WebPMuxCreate(bitstream, 0);
151
26
    if (mux == NULL) return WEBP_MUX_BAD_DATA;
152
26
    wpi = mux->images;
153
26
    assert(wpi != NULL && wpi->img != NULL);
154
26
    *image = wpi->img->data;
155
26
    if (wpi->alpha != NULL) {
156
0
      *alpha = wpi->alpha->data;
157
0
    }
158
26
    WebPMuxDelete(mux);
159
26
  }
160
26
  *is_lossless = VP8LCheckSignature(image->bytes, image->size);
161
26
  return WEBP_MUX_OK;
162
26
}
163
164
52
static WebPMuxError DeleteChunks(WebPChunk** chunk_list, uint32_t tag) {
165
52
  WebPMuxError err = WEBP_MUX_NOT_FOUND;
166
52
  assert(chunk_list);
167
52
  while (*chunk_list) {
168
0
    WebPChunk* const chunk = *chunk_list;
169
0
    if (chunk->tag == tag) {
170
0
      *chunk_list = ChunkDelete(chunk);
171
0
      err = WEBP_MUX_OK;
172
0
    } else {
173
0
      chunk_list = &chunk->next;
174
0
    }
175
0
  }
176
52
  return err;
177
52
}
178
179
52
static WebPMuxError MuxDeleteAllNamedData(WebPMux* const mux, uint32_t tag) {
180
52
  const WebPChunkId id = ChunkGetIdFromTag(tag);
181
52
  assert(mux != NULL);
182
52
  if (IsWPI(id)) return WEBP_MUX_INVALID_ARGUMENT;
183
52
  return DeleteChunks(MuxGetChunkListFromId(mux, id), tag);
184
52
}
185
186
//------------------------------------------------------------------------------
187
// Set API(s).
188
189
WebPMuxError WebPMuxSetChunk(WebPMux* mux, const char fourcc[4],
190
26
                             const WebPData* chunk_data, int copy_data) {
191
26
  uint32_t tag;
192
26
  WebPMuxError err;
193
26
  if (mux == NULL || fourcc == NULL || chunk_data == NULL ||
194
26
      chunk_data->bytes == NULL || chunk_data->size > MAX_CHUNK_PAYLOAD) {
195
0
    return WEBP_MUX_INVALID_ARGUMENT;
196
0
  }
197
26
  tag = ChunkGetTagFromFourCC(fourcc);
198
199
  // Delete existing chunk(s) with the same 'fourcc'.
200
26
  err = MuxDeleteAllNamedData(mux, tag);
201
26
  if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
202
203
  // Add the given chunk.
204
26
  return MuxSet(mux, tag, chunk_data, copy_data);
205
26
}
206
207
// Creates a chunk from given 'data' and sets it as 1st chunk in 'chunk_list'.
208
static WebPMuxError AddDataToChunkList(
209
    const WebPData* const data, int copy_data, uint32_t tag,
210
26
    WebPChunk** chunk_list) {
211
26
  WebPChunk chunk;
212
26
  WebPMuxError err;
213
26
  ChunkInit(&chunk);
214
26
  err = ChunkAssignData(&chunk, data, copy_data, tag);
215
26
  if (err != WEBP_MUX_OK) goto Err;
216
26
  err = ChunkSetHead(&chunk, chunk_list);
217
26
  if (err != WEBP_MUX_OK) goto Err;
218
26
  return WEBP_MUX_OK;
219
0
 Err:
220
0
  ChunkRelease(&chunk);
221
0
  return err;
222
26
}
223
224
// Extracts image & alpha data from the given bitstream and then sets wpi.alpha
225
// and wpi.img appropriately.
226
static WebPMuxError SetAlphaAndImageChunks(
227
26
    const WebPData* const bitstream, int copy_data, WebPMuxImage* const wpi) {
228
26
  int is_lossless = 0;
229
26
  WebPData image, alpha;
230
26
  WebPMuxError err = GetImageData(bitstream, &image, &alpha, &is_lossless);
231
26
  const int image_tag =
232
26
      is_lossless ? kChunks[IDX_VP8L].tag : kChunks[IDX_VP8].tag;
233
26
  if (err != WEBP_MUX_OK) return err;
234
26
  if (alpha.bytes != NULL) {
235
0
    err = AddDataToChunkList(&alpha, copy_data, kChunks[IDX_ALPHA].tag,
236
0
                             &wpi->alpha);
237
0
    if (err != WEBP_MUX_OK) return err;
238
0
  }
239
26
  err = AddDataToChunkList(&image, copy_data, image_tag, &wpi->img);
240
26
  if (err != WEBP_MUX_OK) return err;
241
26
  return MuxImageFinalize(wpi) ? WEBP_MUX_OK : WEBP_MUX_INVALID_ARGUMENT;
242
26
}
243
244
WebPMuxError WebPMuxSetImage(WebPMux* mux, const WebPData* bitstream,
245
26
                             int copy_data) {
246
26
  WebPMuxImage wpi;
247
26
  WebPMuxError err;
248
249
26
  if (mux == NULL || bitstream == NULL || bitstream->bytes == NULL ||
250
26
      bitstream->size > MAX_CHUNK_PAYLOAD) {
251
0
    return WEBP_MUX_INVALID_ARGUMENT;
252
0
  }
253
254
26
  if (mux->images != NULL) {
255
    // Only one 'simple image' can be added in mux. So, remove present images.
256
0
    DeleteAllImages(&mux->images);
257
0
  }
258
259
26
  MuxImageInit(&wpi);
260
26
  err = SetAlphaAndImageChunks(bitstream, copy_data, &wpi);
261
26
  if (err != WEBP_MUX_OK) goto Err;
262
263
  // Add this WebPMuxImage to mux.
264
26
  err = MuxImagePush(&wpi, &mux->images);
265
26
  if (err != WEBP_MUX_OK) goto Err;
266
267
  // All is well.
268
26
  return WEBP_MUX_OK;
269
270
0
 Err:  // Something bad happened.
271
0
  MuxImageRelease(&wpi);
272
0
  return err;
273
26
}
274
275
WebPMuxError WebPMuxPushFrame(WebPMux* mux, const WebPMuxFrameInfo* info,
276
0
                              int copy_data) {
277
0
  WebPMuxImage wpi;
278
0
  WebPMuxError err;
279
280
0
  if (mux == NULL || info == NULL) return WEBP_MUX_INVALID_ARGUMENT;
281
282
0
  if (info->id != WEBP_CHUNK_ANMF) return WEBP_MUX_INVALID_ARGUMENT;
283
284
0
  if (info->bitstream.bytes == NULL ||
285
0
      info->bitstream.size > MAX_CHUNK_PAYLOAD) {
286
0
    return WEBP_MUX_INVALID_ARGUMENT;
287
0
  }
288
289
0
  if (mux->images != NULL) {
290
0
    const WebPMuxImage* const image = mux->images;
291
0
    const uint32_t image_id = (image->header != NULL) ?
292
0
        ChunkGetIdFromTag(image->header->tag) : WEBP_CHUNK_IMAGE;
293
0
    if (image_id != info->id) {
294
0
      return WEBP_MUX_INVALID_ARGUMENT;  // Conflicting frame types.
295
0
    }
296
0
  }
297
298
0
  MuxImageInit(&wpi);
299
0
  err = SetAlphaAndImageChunks(&info->bitstream, copy_data, &wpi);
300
0
  if (err != WEBP_MUX_OK) goto Err;
301
0
  assert(wpi.img != NULL);  // As SetAlphaAndImageChunks() was successful.
302
303
0
  {
304
0
    WebPData frame;
305
0
    const uint32_t tag = kChunks[IDX_ANMF].tag;
306
0
    WebPMuxFrameInfo tmp = *info;
307
0
    tmp.x_offset &= ~1;  // Snap offsets to even.
308
0
    tmp.y_offset &= ~1;
309
0
    if (tmp.x_offset < 0 || tmp.x_offset >= MAX_POSITION_OFFSET ||
310
0
        tmp.y_offset < 0 || tmp.y_offset >= MAX_POSITION_OFFSET ||
311
0
        (tmp.duration < 0 || tmp.duration >= MAX_DURATION) ||
312
0
        tmp.dispose_method != (tmp.dispose_method & 1)) {
313
0
      err = WEBP_MUX_INVALID_ARGUMENT;
314
0
      goto Err;
315
0
    }
316
0
    err = CreateFrameData(wpi.width, wpi.height, &tmp, &frame);
317
0
    if (err != WEBP_MUX_OK) goto Err;
318
    // Add frame chunk (with copy_data = 1).
319
0
    err = AddDataToChunkList(&frame, 1, tag, &wpi.header);
320
0
    WebPDataClear(&frame);  // frame owned by wpi.header now.
321
0
    if (err != WEBP_MUX_OK) goto Err;
322
0
  }
323
324
  // Add this WebPMuxImage to mux.
325
0
  err = MuxImagePush(&wpi, &mux->images);
326
0
  if (err != WEBP_MUX_OK) goto Err;
327
328
  // All is well.
329
0
  return WEBP_MUX_OK;
330
331
0
 Err:  // Something bad happened.
332
0
  MuxImageRelease(&wpi);
333
0
  return err;
334
0
}
335
336
WebPMuxError WebPMuxSetAnimationParams(WebPMux* mux,
337
0
                                       const WebPMuxAnimParams* params) {
338
0
  WebPMuxError err;
339
0
  uint8_t data[ANIM_CHUNK_SIZE];
340
0
  const WebPData anim = { data, ANIM_CHUNK_SIZE };
341
342
0
  if (mux == NULL || params == NULL) return WEBP_MUX_INVALID_ARGUMENT;
343
0
  if (params->loop_count < 0 || params->loop_count >= MAX_LOOP_COUNT) {
344
0
    return WEBP_MUX_INVALID_ARGUMENT;
345
0
  }
346
347
  // Delete any existing ANIM chunk(s).
348
0
  err = MuxDeleteAllNamedData(mux, kChunks[IDX_ANIM].tag);
349
0
  if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
350
351
  // Set the animation parameters.
352
0
  PutLE32(data, params->bgcolor);
353
0
  PutLE16(data + 4, params->loop_count);
354
0
  return MuxSet(mux, kChunks[IDX_ANIM].tag, &anim, 1);
355
0
}
356
357
WebPMuxError WebPMuxSetCanvasSize(WebPMux* mux,
358
0
                                  int width, int height) {
359
0
  WebPMuxError err;
360
0
  if (mux == NULL) {
361
0
    return WEBP_MUX_INVALID_ARGUMENT;
362
0
  }
363
0
  if (width < 0 || height < 0 ||
364
0
      width > MAX_CANVAS_SIZE || height > MAX_CANVAS_SIZE) {
365
0
    return WEBP_MUX_INVALID_ARGUMENT;
366
0
  }
367
0
  if (width * (uint64_t)height >= MAX_IMAGE_AREA) {
368
0
    return WEBP_MUX_INVALID_ARGUMENT;
369
0
  }
370
0
  if ((width * height) == 0 && (width | height) != 0) {
371
    // one of width / height is zero, but not both -> invalid!
372
0
    return WEBP_MUX_INVALID_ARGUMENT;
373
0
  }
374
  // If we already assembled a VP8X chunk, invalidate it.
375
0
  err = MuxDeleteAllNamedData(mux, kChunks[IDX_VP8X].tag);
376
0
  if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
377
378
0
  mux->canvas_width = width;
379
0
  mux->canvas_height = height;
380
0
  return WEBP_MUX_OK;
381
0
}
382
383
//------------------------------------------------------------------------------
384
// Delete API(s).
385
386
0
WebPMuxError WebPMuxDeleteChunk(WebPMux* mux, const char fourcc[4]) {
387
0
  if (mux == NULL || fourcc == NULL) return WEBP_MUX_INVALID_ARGUMENT;
388
0
  return MuxDeleteAllNamedData(mux, ChunkGetTagFromFourCC(fourcc));
389
0
}
390
391
0
WebPMuxError WebPMuxDeleteFrame(WebPMux* mux, uint32_t nth) {
392
0
  if (mux == NULL) return WEBP_MUX_INVALID_ARGUMENT;
393
0
  return MuxImageDeleteNth(&mux->images, nth);
394
0
}
395
396
//------------------------------------------------------------------------------
397
// Assembly of the WebP RIFF file.
398
399
static WebPMuxError GetFrameInfo(
400
    const WebPChunk* const frame_chunk,
401
0
    int* const x_offset, int* const y_offset, int* const duration) {
402
0
  const WebPData* const data = &frame_chunk->data;
403
0
  const size_t expected_data_size = ANMF_CHUNK_SIZE;
404
0
  assert(frame_chunk->tag == kChunks[IDX_ANMF].tag);
405
0
  assert(frame_chunk != NULL);
406
0
  if (data->size != expected_data_size) return WEBP_MUX_INVALID_ARGUMENT;
407
408
0
  *x_offset = 2 * GetLE24(data->bytes + 0);
409
0
  *y_offset = 2 * GetLE24(data->bytes + 3);
410
0
  *duration = GetLE24(data->bytes + 12);
411
0
  return WEBP_MUX_OK;
412
0
}
413
414
static WebPMuxError GetImageInfo(const WebPMuxImage* const wpi,
415
                                 int* const x_offset, int* const y_offset,
416
                                 int* const duration,
417
0
                                 int* const width, int* const height) {
418
0
  const WebPChunk* const frame_chunk = wpi->header;
419
0
  WebPMuxError err;
420
0
  assert(wpi != NULL);
421
0
  assert(frame_chunk != NULL);
422
423
  // Get offsets and duration from ANMF chunk.
424
0
  err = GetFrameInfo(frame_chunk, x_offset, y_offset, duration);
425
0
  if (err != WEBP_MUX_OK) return err;
426
427
  // Get width and height from VP8/VP8L chunk.
428
0
  if (width != NULL) *width = wpi->width;
429
0
  if (height != NULL) *height = wpi->height;
430
0
  return WEBP_MUX_OK;
431
0
}
432
433
// Returns the tightest dimension for the canvas considering the image list.
434
static WebPMuxError GetAdjustedCanvasSize(const WebPMux* const mux,
435
26
                                          int* const width, int* const height) {
436
26
  WebPMuxImage* wpi = NULL;
437
26
  assert(mux != NULL);
438
26
  assert(width != NULL && height != NULL);
439
440
26
  wpi = mux->images;
441
26
  assert(wpi != NULL);
442
26
  assert(wpi->img != NULL);
443
444
26
  if (wpi->next != NULL) {
445
0
    int max_x = 0, max_y = 0;
446
    // if we have a chain of wpi's, header is necessarily set
447
0
    assert(wpi->header != NULL);
448
    // Aggregate the bounding box for animation frames.
449
0
    for (; wpi != NULL; wpi = wpi->next) {
450
0
      int x_offset = 0, y_offset = 0, duration = 0, w = 0, h = 0;
451
0
      const WebPMuxError err = GetImageInfo(wpi, &x_offset, &y_offset,
452
0
                                            &duration, &w, &h);
453
0
      const int max_x_pos = x_offset + w;
454
0
      const int max_y_pos = y_offset + h;
455
0
      if (err != WEBP_MUX_OK) return err;
456
0
      assert(x_offset < MAX_POSITION_OFFSET);
457
0
      assert(y_offset < MAX_POSITION_OFFSET);
458
459
0
      if (max_x_pos > max_x) max_x = max_x_pos;
460
0
      if (max_y_pos > max_y) max_y = max_y_pos;
461
0
    }
462
0
    *width = max_x;
463
0
    *height = max_y;
464
26
  } else {
465
    // For a single image, canvas dimensions are same as image dimensions.
466
26
    *width = wpi->width;
467
26
    *height = wpi->height;
468
26
  }
469
26
  return WEBP_MUX_OK;
470
26
}
471
472
// VP8X format:
473
// Total Size : 10,
474
// Flags  : 4 bytes,
475
// Width  : 3 bytes,
476
// Height : 3 bytes.
477
26
static WebPMuxError CreateVP8XChunk(WebPMux* const mux) {
478
26
  WebPMuxError err = WEBP_MUX_OK;
479
26
  uint32_t flags = 0;
480
26
  int width = 0;
481
26
  int height = 0;
482
26
  uint8_t data[VP8X_CHUNK_SIZE];
483
26
  const WebPData vp8x = { data, VP8X_CHUNK_SIZE };
484
26
  const WebPMuxImage* images = NULL;
485
486
26
  assert(mux != NULL);
487
26
  images = mux->images;  // First image.
488
26
  if (images == NULL || images->img == NULL ||
489
26
      images->img->data.bytes == NULL) {
490
0
    return WEBP_MUX_INVALID_ARGUMENT;
491
0
  }
492
493
  // If VP8X chunk(s) is(are) already present, remove them (and later add new
494
  // VP8X chunk with updated flags).
495
26
  err = MuxDeleteAllNamedData(mux, kChunks[IDX_VP8X].tag);
496
26
  if (err != WEBP_MUX_OK && err != WEBP_MUX_NOT_FOUND) return err;
497
498
  // Set flags.
499
26
  if (mux->iccp != NULL && mux->iccp->data.bytes != NULL) {
500
1
    flags |= ICCP_FLAG;
501
1
  }
502
26
  if (mux->exif != NULL && mux->exif->data.bytes != NULL) {
503
25
    flags |= EXIF_FLAG;
504
25
  }
505
26
  if (mux->xmp != NULL && mux->xmp->data.bytes != NULL) {
506
0
    flags |= XMP_FLAG;
507
0
  }
508
26
  if (images->header != NULL) {
509
0
    if (images->header->tag == kChunks[IDX_ANMF].tag) {
510
      // This is an image with animation.
511
0
      flags |= ANIMATION_FLAG;
512
0
    }
513
0
  }
514
26
  if (MuxImageCount(images, WEBP_CHUNK_ALPHA) > 0) {
515
0
    flags |= ALPHA_FLAG;  // Some images have an alpha channel.
516
0
  }
517
518
26
  err = GetAdjustedCanvasSize(mux, &width, &height);
519
26
  if (err != WEBP_MUX_OK) return err;
520
521
26
  if (width <= 0 || height <= 0) {
522
0
    return WEBP_MUX_INVALID_ARGUMENT;
523
0
  }
524
26
  if (width > MAX_CANVAS_SIZE || height > MAX_CANVAS_SIZE) {
525
0
    return WEBP_MUX_INVALID_ARGUMENT;
526
0
  }
527
528
26
  if (mux->canvas_width != 0 || mux->canvas_height != 0) {
529
0
    if (width > mux->canvas_width || height > mux->canvas_height) {
530
0
      return WEBP_MUX_INVALID_ARGUMENT;
531
0
    }
532
0
    width = mux->canvas_width;
533
0
    height = mux->canvas_height;
534
0
  }
535
536
26
  if (flags == 0 && mux->unknown == NULL) {
537
    // For simple file format, VP8X chunk should not be added.
538
0
    return WEBP_MUX_OK;
539
0
  }
540
541
26
  if (MuxHasAlpha(images)) {
542
    // This means some frames explicitly/implicitly contain alpha.
543
    // Note: This 'flags' update must NOT be done for a lossless image
544
    // without a VP8X chunk!
545
0
    flags |= ALPHA_FLAG;
546
0
  }
547
548
26
  PutLE32(data + 0, flags);   // VP8X chunk flags.
549
26
  PutLE24(data + 4, width - 1);   // canvas width.
550
26
  PutLE24(data + 7, height - 1);  // canvas height.
551
552
26
  return MuxSet(mux, kChunks[IDX_VP8X].tag, &vp8x, 1);
553
26
}
554
555
// Cleans up 'mux' by removing any unnecessary chunks.
556
26
static WebPMuxError MuxCleanup(WebPMux* const mux) {
557
26
  int num_frames;
558
26
  int num_anim_chunks;
559
560
  // If we have an image with a single frame, and its rectangle
561
  // covers the whole canvas, convert it to a non-animated image
562
  // (to avoid writing ANMF chunk unnecessarily).
563
26
  WebPMuxError err = WebPMuxNumChunks(mux, kChunks[IDX_ANMF].id, &num_frames);
564
26
  if (err != WEBP_MUX_OK) return err;
565
26
  if (num_frames == 1) {
566
0
    WebPMuxImage* frame = NULL;
567
0
    err = MuxImageGetNth((const WebPMuxImage**)&mux->images, 1, &frame);
568
0
    if (err != WEBP_MUX_OK) return err;
569
    // We know that one frame does exist.
570
0
    assert(frame != NULL);
571
0
    if (frame->header != NULL &&
572
0
        ((mux->canvas_width == 0 && mux->canvas_height == 0) ||
573
0
         (frame->width == mux->canvas_width &&
574
0
          frame->height == mux->canvas_height))) {
575
0
      assert(frame->header->tag == kChunks[IDX_ANMF].tag);
576
0
      ChunkDelete(frame->header);  // Removes ANMF chunk.
577
0
      frame->header = NULL;
578
0
      num_frames = 0;
579
0
    }
580
0
  }
581
  // Remove ANIM chunk if this is a non-animated image.
582
26
  err = WebPMuxNumChunks(mux, kChunks[IDX_ANIM].id, &num_anim_chunks);
583
26
  if (err != WEBP_MUX_OK) return err;
584
26
  if (num_anim_chunks >= 1 && num_frames == 0) {
585
0
    err = MuxDeleteAllNamedData(mux, kChunks[IDX_ANIM].tag);
586
0
    if (err != WEBP_MUX_OK) return err;
587
0
  }
588
26
  return WEBP_MUX_OK;
589
26
}
590
591
// Total size of a list of images.
592
26
static size_t ImageListDiskSize(const WebPMuxImage* wpi_list) {
593
26
  size_t size = 0;
594
52
  while (wpi_list != NULL) {
595
26
    size += MuxImageDiskSize(wpi_list);
596
26
    wpi_list = wpi_list->next;
597
26
  }
598
26
  return size;
599
26
}
600
601
// Write out the given list of images into 'dst'.
602
26
static uint8_t* ImageListEmit(const WebPMuxImage* wpi_list, uint8_t* dst) {
603
52
  while (wpi_list != NULL) {
604
26
    dst = MuxImageEmit(wpi_list, dst);
605
26
    wpi_list = wpi_list->next;
606
26
  }
607
26
  return dst;
608
26
}
609
610
26
WebPMuxError WebPMuxAssemble(WebPMux* mux, WebPData* assembled_data) {
611
26
  size_t size = 0;
612
26
  uint8_t* data = NULL;
613
26
  uint8_t* dst = NULL;
614
26
  WebPMuxError err;
615
616
26
  if (assembled_data == NULL) {
617
0
    return WEBP_MUX_INVALID_ARGUMENT;
618
0
  }
619
  // Clean up returned data, in case something goes wrong.
620
26
  memset(assembled_data, 0, sizeof(*assembled_data));
621
622
26
  if (mux == NULL) {
623
0
    return WEBP_MUX_INVALID_ARGUMENT;
624
0
  }
625
626
  // Finalize mux.
627
26
  err = MuxCleanup(mux);
628
26
  if (err != WEBP_MUX_OK) return err;
629
26
  err = CreateVP8XChunk(mux);
630
26
  if (err != WEBP_MUX_OK) return err;
631
632
  // Allocate data.
633
26
  size = ChunkListDiskSize(mux->vp8x) + ChunkListDiskSize(mux->iccp)
634
26
       + ChunkListDiskSize(mux->anim) + ImageListDiskSize(mux->images)
635
26
       + ChunkListDiskSize(mux->exif) + ChunkListDiskSize(mux->xmp)
636
26
       + ChunkListDiskSize(mux->unknown) + RIFF_HEADER_SIZE;
637
638
26
  data = (uint8_t*)WebPSafeMalloc(1ULL, size);
639
26
  if (data == NULL) return WEBP_MUX_MEMORY_ERROR;
640
641
  // Emit header & chunks.
642
26
  dst = MuxEmitRiffHeader(data, size);
643
26
  dst = ChunkListEmit(mux->vp8x, dst);
644
26
  dst = ChunkListEmit(mux->iccp, dst);
645
26
  dst = ChunkListEmit(mux->anim, dst);
646
26
  dst = ImageListEmit(mux->images, dst);
647
26
  dst = ChunkListEmit(mux->exif, dst);
648
26
  dst = ChunkListEmit(mux->xmp, dst);
649
26
  dst = ChunkListEmit(mux->unknown, dst);
650
26
  assert(dst == data + size);
651
652
  // Validate mux.
653
26
  err = MuxValidate(mux);
654
26
  if (err != WEBP_MUX_OK) {
655
0
    WebPSafeFree(data);
656
0
    data = NULL;
657
0
    size = 0;
658
0
  }
659
660
  // Finalize data.
661
26
  assembled_data->bytes = data;
662
26
  assembled_data->size = size;
663
664
26
  return err;
665
26
}
666
667
//------------------------------------------------------------------------------