forked from micropython/micropython
-
Notifications
You must be signed in to change notification settings - Fork 1.3k
/
Copy pathgif.c
1043 lines (999 loc) · 39.1 KB
/
gif.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
//
// GIF Animator
// written by Larry Bank
// bitbank@pobox.com
// Arduino port started 7/5/2020
// Original GIF code written 20+ years ago :)
// The goal of this code is to decode images up to 480x320
// using no more than 22K of RAM (if sent directly to an LCD display)
//
// Copyright 2020 BitBank Software, Inc. All Rights Reserved.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//===========================================================================
//
// Modified 2023 by Mark Komus to work for CircuitPython
//
#include "AnimatedGIF_circuitpy.h"
#ifdef HAL_ESP32_HAL_H_
#define memcpy_P memcpy
#endif
static const unsigned char cGIFBits[9] = {1,4,4,4,8,8,8,8,8}; // convert odd bpp values to ones we can handle
// forward references
static int GIFInit(GIFIMAGE *pGIF);
static int GIFParseInfo(GIFIMAGE *pPage, int bInfoOnly);
static int GIFGetMoreData(GIFIMAGE *pPage);
static void GIFMakePels(GIFIMAGE *pPage, unsigned int code);
static int DecodeLZW(GIFIMAGE *pImage, int iOptions);
static int32_t readMem(GIFFILE *pFile, uint8_t *pBuf, int32_t iLen);
static int32_t seekMem(GIFFILE *pFile, int32_t iPosition);
int GIF_getInfo(GIFIMAGE *pPage, GIFINFO *pInfo);
#if defined ( __LINUX__ ) || defined( __MCUXPRESSO )
static int32_t readFile(GIFFILE *pFile, uint8_t *pBuf, int32_t iLen);
static int32_t seekFile(GIFFILE *pFile, int32_t iPosition);
static void closeFile(void *handle);
#endif
// C API
int GIF_openRAM(GIFIMAGE *pGIF, uint8_t *pData, int iDataSize, GIF_DRAW_CALLBACK *pfnDraw)
{
pGIF->iError = GIF_SUCCESS;
pGIF->pfnRead = readMem;
pGIF->pfnSeek = seekMem;
pGIF->pfnDraw = pfnDraw;
pGIF->pfnOpen = NULL;
pGIF->pfnClose = NULL;
pGIF->GIFFile.iSize = iDataSize;
pGIF->GIFFile.pData = pData;
return GIFInit(pGIF);
} /* GIF_openRAM() */
#ifdef __LINUX__
int GIF_openFile(GIFIMAGE *pGIF, const char *szFilename, GIF_DRAW_CALLBACK *pfnDraw)
{
pGIF->iError = GIF_SUCCESS;
pGIF->pfnRead = readFile;
pGIF->pfnSeek = seekFile;
pGIF->pfnDraw = pfnDraw;
pGIF->pfnOpen = NULL;
pGIF->pfnClose = closeFile;
pGIF->GIFFile.fHandle = fopen(szFilename, "r+b");
if (pGIF->GIFFile.fHandle == NULL)
return 0;
fseek((FILE *)pGIF->GIFFile.fHandle, 0, SEEK_END);
pGIF->GIFFile.iSize = (int)ftell((FILE *)pGIF->GIFFile.fHandle);
fseek((FILE *)pGIF->GIFFile.fHandle, 0, SEEK_SET);
return GIFInit(pGIF);
} /* GIF_openFile() */
#endif
void GIF_close(GIFIMAGE *pGIF)
{
if (pGIF->pfnClose)
(*pGIF->pfnClose)(pGIF->GIFFile.fHandle);
} /* GIF_close() */
void GIF_begin(GIFIMAGE *pGIF, unsigned char ucPaletteType)
{
memset(pGIF, 0, sizeof(GIFIMAGE));
pGIF->ucPaletteType = ucPaletteType;
} /* GIF_begin() */
void GIF_reset(GIFIMAGE *pGIF)
{
(*pGIF->pfnSeek)(&pGIF->GIFFile, 0);
} /* GIF_reset() */
//
// Return value:
// 1 = good decode, more frames exist
// 0 = good decode, no more frames
// -1 = error
//
int GIF_playFrame(GIFIMAGE *pGIF, int *delayMilliseconds, void *pUser)
{
int rc;
if (delayMilliseconds)
*delayMilliseconds = 0; // clear any old valid
if (pGIF->GIFFile.iPos >= pGIF->GIFFile.iSize-1) // no more data exists
{
(*pGIF->pfnSeek)(&pGIF->GIFFile, 0); // seek to start
}
if (GIFParseInfo(pGIF, 0))
{
pGIF->pUser = pUser;
if (pGIF->iError == GIF_EMPTY_FRAME) // don't try to decode it
return 0;
rc = DecodeLZW(pGIF, 0);
if (rc != 0) // problem
return 0;
}
else
{
return 0; // error parsing the frame info, we may be at the end of the file
}
// Return 1 for more frames or 0 if this was the last frame
if (delayMilliseconds) // if not NULL, return the frame delay time
*delayMilliseconds = pGIF->iFrameDelay;
return (pGIF->GIFFile.iPos < pGIF->GIFFile.iSize-1);
} /* GIF_playFrame() */
int GIF_getCanvasWidth(GIFIMAGE *pGIF)
{
return pGIF->iCanvasWidth;
} /* GIF_getCanvasWidth() */
int GIF_getCanvasHeight(GIFIMAGE *pGIF)
{
return pGIF->iCanvasHeight;
} /* GIF_getCanvasHeight() */
int GIF_getLoopCount(GIFIMAGE *pGIF)
{
return pGIF->iRepeatCount;
} /* GIF_getLoopCount() */
int GIF_getComment(GIFIMAGE *pGIF, char *pDest)
{
int32_t iOldPos;
iOldPos = pGIF->GIFFile.iPos; // keep old position
(*pGIF->pfnSeek)(&pGIF->GIFFile, pGIF->iCommentPos);
(*pGIF->pfnRead)(&pGIF->GIFFile, (uint8_t *)pDest, pGIF->sCommentLen);
(*pGIF->pfnSeek)(&pGIF->GIFFile, iOldPos);
pDest[pGIF->sCommentLen] = 0; // zero terminate the string
return (int)pGIF->sCommentLen;
} /* GIF_getComment() */
int GIF_getLastError(GIFIMAGE *pGIF)
{
return pGIF->iError;
} /* GIF_getLastError() */
int GIF_init(GIFIMAGE *pGIF) {
return GIFInit(pGIF);
}
//
// Helper functions for memory based images
//
static int32_t readMem(GIFFILE *pFile, uint8_t *pBuf, int32_t iLen)
{
int32_t iBytesRead;
iBytesRead = iLen;
if ((pFile->iSize - pFile->iPos) < iLen)
iBytesRead = pFile->iSize - pFile->iPos;
if (iBytesRead <= 0)
return 0;
memmove(pBuf, &pFile->pData[pFile->iPos], iBytesRead);
pFile->iPos += iBytesRead;
return iBytesRead;
} /* readMem() */
#ifndef CIRCUITPY
static int32_t readFLASH(GIFFILE *pFile, uint8_t *pBuf, int32_t iLen)
{
int32_t iBytesRead;
iBytesRead = iLen;
if ((pFile->iSize - pFile->iPos) < iLen)
iBytesRead = pFile->iSize - pFile->iPos;
if (iBytesRead <= 0)
return 0;
memcpy_P(pBuf, &pFile->pData[pFile->iPos], iBytesRead);
pFile->iPos += iBytesRead;
return iBytesRead;
} /* readFLASH() */
#endif
static int32_t seekMem(GIFFILE *pFile, int32_t iPosition)
{
if (iPosition < 0) iPosition = 0;
else if (iPosition >= pFile->iSize) iPosition = pFile->iSize-1;
pFile->iPos = iPosition;
return iPosition;
} /* seekMem() */
#if defined ( __LINUX__ ) || defined( __MCUXPRESSO )
static void closeFile(void *handle)
{
fclose((FILE *)handle);
} /* closeFile() */
static int32_t seekFile(GIFFILE *pFile, int32_t iPosition)
{
if (iPosition < 0) iPosition = 0;
else if (iPosition >= pFile->iSize) iPosition = pFile->iSize-1;
pFile->iPos = iPosition;
fseek((FILE *)pFile->fHandle, iPosition, SEEK_SET);
return iPosition;
} /* seekMem() */
static int32_t readFile(GIFFILE *pFile, uint8_t *pBuf, int32_t iLen)
{
int32_t iBytesRead;
iBytesRead = iLen;
if ((pFile->iSize - pFile->iPos) < iLen)
iBytesRead = pFile->iSize - pFile->iPos;
if (iBytesRead <= 0)
return 0;
iBytesRead = (int)fread(pBuf, 1, iBytesRead, (FILE *)pFile->fHandle);
pFile->iPos += iBytesRead;
return iBytesRead;
} /* readFile() */
#endif // __LINUX__
//
// The following functions are written in plain C and have no
// 3rd party dependencies, not even the C runtime library
//
//
// Initialize a GIF file and callback access from a file on SD or memory
// returns 1 for success, 0 for failure
// Fills in the canvas size of the GIFIMAGE structure
//
static int GIFInit(GIFIMAGE *pGIF)
{
pGIF->GIFFile.iPos = 0; // start at beginning of file
if (!GIFParseInfo(pGIF, 1)) // gather info for the first frame
return 0; // something went wrong; not a GIF file?
(*pGIF->pfnSeek)(&pGIF->GIFFile, 0); // seek back to start of the file
if (pGIF->iCanvasWidth > MAX_WIDTH) { // need to allocate more space
pGIF->iError = GIF_TOO_WIDE;
return 0;
}
return 1;
} /* GIFInit() */
//
// Parse the GIF header, gather the size and palette info
// If called with bInfoOnly set to true, it will test for a valid file
// and return the canvas size only
// Returns 1 for success, 0 for failure
//
static int GIFParseInfo(GIFIMAGE *pPage, int bInfoOnly)
{
int i, j, iColorTableBits;
int iBytesRead;
unsigned char c, *p;
int32_t iOffset = 0;
int32_t iStartPos = pPage->GIFFile.iPos; // starting file position
int iReadSize;
pPage->bUseLocalPalette = 0; // assume no local palette
pPage->bEndOfFrame = 0; // we're just getting started
pPage->iFrameDelay = 0; // may not have a gfx extension block
pPage->iRepeatCount = -1; // assume NETSCAPE loop count is not specified
iReadSize = (bInfoOnly) ? 12 : MAX_CHUNK_SIZE;
// If you try to read past the EOF, the SD lib will return garbage data
if (iStartPos + iReadSize > pPage->GIFFile.iSize)
iReadSize = (pPage->GIFFile.iSize - iStartPos - 1);
p = pPage->ucFileBuf;
iBytesRead = (*pPage->pfnRead)(&pPage->GIFFile, pPage->ucFileBuf, iReadSize); // 255 is plenty for now
if (iBytesRead != iReadSize) // we're at the end of the file
{
pPage->iError = GIF_EARLY_EOF;
return 0;
}
if (iStartPos == 0) // start of the file
{ // canvas size
if (memcmp(p, "GIF89", 5) != 0 && memcmp(p, "GIF87", 5) != 0) // not a GIF file
{
pPage->iError = GIF_BAD_FILE;
return 0;
}
pPage->iCanvasWidth = pPage->iWidth = INTELSHORT(&p[6]);
pPage->iCanvasHeight = pPage->iHeight = INTELSHORT(&p[8]);
pPage->iBpp = ((p[10] & 0x70) >> 4) + 1;
if (bInfoOnly)
return 1; // we've got the info we needed, leave
iColorTableBits = (p[10] & 7) + 1; // Log2(size) of the color table
pPage->ucBackground = p[11]; // background color
pPage->ucGIFBits = 0;
iOffset = 13;
if (p[10] & 0x80) // global color table?
{ // by default, convert to byte-reversed RGB565 for immediate use
// Read enough additional data for the color table
iBytesRead += (*pPage->pfnRead)(&pPage->GIFFile, &pPage->ucFileBuf[iBytesRead], 3*(1<<iColorTableBits));
if (pPage->ucPaletteType == GIF_PALETTE_RGB565_LE || pPage->ucPaletteType == GIF_PALETTE_RGB565_BE)
{
for (i=0; i<(1<<iColorTableBits); i++)
{
uint16_t usRGB565;
usRGB565 = ((p[iOffset] >> 3) << 11); // R
usRGB565 |= ((p[iOffset+1] >> 2) << 5); // G
usRGB565 |= (p[iOffset+2] >> 3); // B
if (pPage->ucPaletteType == GIF_PALETTE_RGB565_LE)
pPage->pPalette[i] = usRGB565;
else
pPage->pPalette[i] = __builtin_bswap16(usRGB565); // SPI wants MSB first
iOffset += 3;
}
}
else // just copy it as-is
{
memcpy(pPage->pPalette, &p[iOffset], (1<<iColorTableBits) * 3);
iOffset += (1 << iColorTableBits) * 3;
}
}
}
while (p[iOffset] != ',' && p[iOffset] != ';') /* Wait for image separator */
{
if (p[iOffset] == '!') /* Extension block */
{
iOffset++;
switch(p[iOffset++]) /* Block type */
{
case 0xf9: /* Graphic extension */
if (p[iOffset] == 4) // correct length
{
pPage->ucGIFBits = p[iOffset+1]; // packed fields
pPage->iFrameDelay = (INTELSHORT(&p[iOffset+2]))*10; // delay in ms
if (pPage->iFrameDelay <= 1) // 0-1 is going to make it run at 60fps; use 100 (10fps) as a reasonable substitute
pPage->iFrameDelay = 100;
if (pPage->ucGIFBits & 1) // transparent color is used
pPage->ucTransparent = p[iOffset+4]; // transparent color index
iOffset += 6;
}
// else // error
break;
case 0xff: /* App extension */
c = 1;
while (c) /* Skip all data sub-blocks */
{
c = p[iOffset++]; /* Block length */
if ((iBytesRead - iOffset) < (c+32)) // need to read more data first
{
memmove(pPage->ucFileBuf, &pPage->ucFileBuf[iOffset], (iBytesRead-iOffset)); // move existing data down
iBytesRead -= iOffset;
iStartPos += iOffset;
iOffset = 0;
iBytesRead += (*pPage->pfnRead)(&pPage->GIFFile, &pPage->ucFileBuf[iBytesRead], c+32);
}
if (c == 11) // fixed block length
{ // Netscape app block contains the repeat count
if (memcmp(&p[iOffset], "NETSCAPE2.0", 11) == 0)
{
if (p[iOffset+11] == 3 && p[iOffset+12] == 1) // loop count
pPage->iRepeatCount = INTELSHORT(&p[iOffset+13]);
}
}
iOffset += (int)c; /* Skip to next sub-block */
}
break;
case 0x01: /* Text extension */
c = 1;
j = 0;
while (c) /* Skip all data sub-blocks */
{
c = p[iOffset++]; /* Block length */
if (j == 0) // use only first block
{
j = c;
if (j > 127) // max comment length = 127
j = 127;
// memcpy(pPage->szInfo1, &p[iOffset], j);
// pPage->szInfo1[j] = '\0';
j = 1;
}
iOffset += (int)c; /* Skip this sub-block */
}
break;
case 0xfe: /* Comment */
c = 1;
while (c) /* Skip all data sub-blocks */
{
c = p[iOffset++]; /* Block length */
if ((iBytesRead - iOffset) < (c+32)) // need to read more data first
{
memmove(pPage->ucFileBuf, &pPage->ucFileBuf[iOffset], (iBytesRead-iOffset)); // move existing data down
iBytesRead -= iOffset;
iStartPos += iOffset;
iOffset = 0;
iBytesRead += (*pPage->pfnRead)(&pPage->GIFFile, &pPage->ucFileBuf[iBytesRead], c+32);
}
if (pPage->iCommentPos == 0) // Save first block info
{
pPage->iCommentPos = iStartPos + iOffset;
pPage->sCommentLen = c;
}
iOffset += (int)c; /* Skip this sub-block */
}
break;
default:
/* Bad header info */
pPage->iError = GIF_DECODE_ERROR;
return 0;
} /* switch */
}
else // invalid byte, stop decoding
{
if (pPage->GIFFile.iSize - iStartPos < 32) // non-image bytes at end of file?
pPage->iError = GIF_EMPTY_FRAME;
else
/* Bad header info */
pPage->iError = GIF_DECODE_ERROR;
return 0;
}
} /* while */
if (p[iOffset] == ';') { // end of file, quit and return a correct error code
pPage->iError = GIF_EMPTY_FRAME;
return 1;
}
if (p[iOffset] == ',')
iOffset++;
// This particular frame's size and position on the main frame (if animated)
pPage->iX = INTELSHORT(&p[iOffset]);
pPage->iY = INTELSHORT(&p[iOffset+2]);
pPage->iWidth = INTELSHORT(&p[iOffset+4]);
pPage->iHeight = INTELSHORT(&p[iOffset+6]);
iOffset += 8;
/* Image descriptor
7 6 5 4 3 2 1 0 M=0 - use global color map, ignore pixel
M I 0 0 0 pixel M=1 - local color map follows, use pixel
I=0 - Image in sequential order
I=1 - Image in interlaced order
pixel+1 = # bits per pixel for this image
*/
pPage->ucMap = p[iOffset++];
if (pPage->ucMap & 0x80) // local color table?
{// by default, convert to byte-reversed RGB565 for immediate use
j = (1<<((pPage->ucMap & 7)+1));
// Read enough additional data for the color table
iBytesRead += (*pPage->pfnRead)(&pPage->GIFFile, &pPage->ucFileBuf[iBytesRead], j*3);
if (pPage->ucPaletteType == GIF_PALETTE_RGB565_LE || pPage->ucPaletteType == GIF_PALETTE_RGB565_BE)
{
for (i=0; i<j; i++)
{
uint16_t usRGB565;
usRGB565 = ((p[iOffset] >> 3) << 11); // R
usRGB565 |= ((p[iOffset+1] >> 2) << 5); // G
usRGB565 |= (p[iOffset+2] >> 3); // B
if (pPage->ucPaletteType == GIF_PALETTE_RGB565_LE)
pPage->pLocalPalette[i] = usRGB565;
else
pPage->pLocalPalette[i] = __builtin_bswap16(usRGB565); // SPI wants MSB first
iOffset += 3;
}
}
else // just copy it as-is
{
memcpy(pPage->pLocalPalette, &p[iOffset], j * 3);
iOffset += j*3;
}
pPage->bUseLocalPalette = 1;
}
pPage->ucCodeStart = p[iOffset++]; /* initial code size */
/* Since GIF can be 1-8 bpp, we only allow 1,4,8 */
pPage->iBpp = cGIFBits[pPage->ucCodeStart];
// we are re-using the same buffer turning GIF file data
// into "pure" LZW
pPage->iLZWSize = 0; // we're starting with no LZW data yet
c = 1; // get chunk length
while (c && iOffset < iBytesRead)
{
// Serial.printf("iOffset=%d, iBytesRead=%d\n", iOffset, iBytesRead);
c = p[iOffset++]; // get chunk length
// Serial.printf("Chunk size = %d\n", c);
if (c <= (iBytesRead - iOffset))
{
memcpy(&pPage->ucLZW[pPage->iLZWSize], &p[iOffset], c);
pPage->iLZWSize += c;
iOffset += c;
}
else // partial chunk in our buffer
{
int iPartialLen = (iBytesRead - iOffset);
memcpy(&pPage->ucLZW[pPage->iLZWSize], &p[iOffset], iPartialLen);
pPage->iLZWSize += iPartialLen;
iOffset += iPartialLen;
(*pPage->pfnRead)(&pPage->GIFFile, &pPage->ucLZW[pPage->iLZWSize], c - iPartialLen);
pPage->iLZWSize += (c - iPartialLen);
}
if (c == 0)
pPage->bEndOfFrame = 1; // signal not to read beyond the end of the frame
}
// seeking on an SD card is VERY VERY SLOW, so use the data we've already read by de-chunking it
// in this case, there's too much data, so we have to seek backwards a bit
if (iOffset < iBytesRead)
{
// Serial.printf("Need to seek back %d bytes\n", iBytesRead - iOffset);
(*pPage->pfnSeek)(&pPage->GIFFile, iStartPos + iOffset); // position file to new spot
}
return 1; // we are now at the start of the chunk data
} /* GIFParseInfo() */
//
// Gather info about an animated GIF file
//
int GIF_getInfo(GIFIMAGE *pPage, GIFINFO *pInfo)
{
int iOff, iNumFrames;
int iDelay, iMaxDelay, iMinDelay, iTotalDelay;
int iReadAmount;
int iDataAvailable = 0;
int iDataRemaining = 0;
uint32_t lFileOff = 0;
int bDone = 0;
int bExt;
uint8_t c, *cBuf;
iMaxDelay = iTotalDelay = 0;
iMinDelay = 10000;
iNumFrames = 1;
iDataRemaining = pPage->GIFFile.iSize;
cBuf = (uint8_t *) pPage->ucFileBuf;
(*pPage->pfnSeek)(&pPage->GIFFile, 0);
iDataAvailable = (*pPage->pfnRead)(&pPage->GIFFile, cBuf, FILE_BUF_SIZE);
iDataRemaining -= iDataAvailable;
lFileOff += iDataAvailable;
iOff = 10;
c = cBuf[iOff]; // get info bits
iOff += 3; /* Skip flags, background color & aspect ratio */
if (c & 0x80) /* Deal with global color table */
{
c &= 7; /* Get the number of colors defined */
iOff += (2<<c)*3; /* skip color table */
}
while (!bDone) // && iNumFrames < MAX_FRAMES)
{
bExt = 1; /* skip extension blocks */
while (bExt && iOff < iDataAvailable)
{
if ((iDataAvailable - iOff) < 258) // need to read more data first
{
memmove(cBuf, &cBuf[iOff], (iDataAvailable-iOff)); // move existing data down
iDataAvailable -= iOff;
iOff = 0;
iReadAmount = (*pPage->pfnRead)(&pPage->GIFFile, &cBuf[iDataAvailable], FILE_BUF_SIZE-iDataAvailable);
iDataAvailable += iReadAmount;
iDataRemaining -= iReadAmount;
lFileOff += iReadAmount;
}
switch(cBuf[iOff])
{
case 0x3b: /* End of file */
/* we were fooled into thinking there were more pages */
iNumFrames--;
goto gifpagesz;
// F9 = Graphic Control Extension (fixed length of 4 bytes)
// FE = Comment Extension
// FF = Application Extension
// 01 = Plain Text Extension
case 0x21: /* Extension block */
if (cBuf[iOff+1] == 0xf9 && cBuf[iOff+2] == 4) // Graphic Control Extension
{
//cBuf[iOff+3]; // page disposition flags
iDelay = cBuf[iOff+4]; // delay low byte
iDelay |= ((uint16_t)(cBuf[iOff+5]) << 8); // delay high byte
if (iDelay < 2) // too fast, provide a default
iDelay = 2;
iDelay *= 10; // turn JIFFIES into milliseconds
iTotalDelay += iDelay;
if (iDelay > iMaxDelay) iMaxDelay = iDelay;
else if (iDelay < iMinDelay) iMinDelay = iDelay;
// (cBuf[iOff+6]; // transparent color index
}
iOff += 2; /* skip to length */
iOff += (int)cBuf[iOff]; /* Skip the data block */
iOff++;
// block terminator or optional sub blocks
c = cBuf[iOff++]; /* Skip any sub-blocks */
while (c)
{
iOff += (int)c;
c = cBuf[iOff++];
if ((iDataAvailable - iOff) < (c+258)) // need to read more data first
{
memmove(cBuf, &cBuf[iOff], (iDataAvailable-iOff)); // move existing data down
iDataAvailable -= iOff;
iOff = 0;
iReadAmount = (*pPage->pfnRead)(&pPage->GIFFile, &cBuf[iDataAvailable], FILE_BUF_SIZE-iDataAvailable);
iDataAvailable += iReadAmount;
iDataRemaining -= iReadAmount;
lFileOff += iReadAmount;
}
}
if (c != 0) // problem, we went past the end
{
iNumFrames--; // possible corrupt data; stop
goto gifpagesz;
}
break;
case 0x2c: /* Start of image data */
bExt = 0; /* Stop doing extension blocks */
break;
default:
/* Corrupt data, stop here */
iNumFrames--;
goto gifpagesz;
} // switch
} // while
if (iOff >= iDataAvailable) // problem
{
iNumFrames--; // possible corrupt data; stop
goto gifpagesz;
}
/* Start of image data */
c = cBuf[iOff+9]; /* Get the flags byte */
iOff += 10; /* Skip image position and size */
if (c & 0x80) /* Local color table */
{
c &= 7;
iOff += (2<<c)*3;
}
iOff++; /* Skip LZW code size byte */
if ((iDataAvailable - iOff) < (c+258)) // need to read more data first
{
if (iOff < iDataAvailable) {
memmove(cBuf, &cBuf[iOff], (iDataAvailable-iOff)); // move existing data down
iDataAvailable -= iOff;
iOff = 0;
} else { // already points beyond end
iOff -= iDataAvailable;
iDataAvailable = 0;
}
iReadAmount = (*pPage->pfnRead)(&pPage->GIFFile, &cBuf[iDataAvailable], FILE_BUF_SIZE-iDataAvailable);
iDataAvailable += iReadAmount;
iDataRemaining -= iReadAmount;
lFileOff += iReadAmount;
}
c = cBuf[iOff++];
while (c) /* While there are more data blocks */
{
if (iOff > (3*FILE_BUF_SIZE/4) && iDataRemaining > 0) /* Near end of buffer, re-align */
{
memmove(cBuf, &cBuf[iOff], (iDataAvailable-iOff)); // move existing data down
iDataAvailable -= iOff;
iOff = 0;
iReadAmount = (FILE_BUF_SIZE - iDataAvailable);
if (iReadAmount > iDataRemaining)
iReadAmount = iDataRemaining;
iReadAmount = (*pPage->pfnRead)(&pPage->GIFFile, &cBuf[iDataAvailable], iReadAmount);
iDataAvailable += iReadAmount;
iDataRemaining -= iReadAmount;
lFileOff += iReadAmount;
}
iOff += (int)c; /* Skip this data block */
// if ((int)lFileOff + iOff > pPage->GIFFile.iSize) // past end of file, stop
// {
// iNumFrames--; // don't count this page
// break; // last page is corrupted, don't use it
// }
c = cBuf[iOff++]; /* Get length of next */
}
/* End of image data, check for more pages... */
if (cBuf[iOff] == 0x3b || (iDataRemaining == 0 && (iDataAvailable - iOff) < 32))
{
bDone = 1; /* End of file has been reached */
}
else /* More pages to scan */
{
iNumFrames++;
// read new page data starting at this offset
if (pPage->GIFFile.iSize > FILE_BUF_SIZE && iDataRemaining > 0) // since we didn't read the whole file in one shot
{
memmove(cBuf, &cBuf[iOff], (iDataAvailable-iOff)); // move existing data down
iDataAvailable -= iOff;
iOff = 0;
iReadAmount = (FILE_BUF_SIZE - iDataAvailable);
if (iReadAmount > iDataRemaining)
iReadAmount = iDataRemaining;
iReadAmount = (*pPage->pfnRead)(&pPage->GIFFile, &cBuf[iDataAvailable], iReadAmount);
iDataAvailable += iReadAmount;
iDataRemaining -= iReadAmount;
lFileOff += iReadAmount;
}
}
} /* while !bDone */
gifpagesz:
pInfo->iFrameCount = iNumFrames;
pInfo->iMaxDelay = iMaxDelay;
pInfo->iMinDelay = iMinDelay;
pInfo->iDuration = iTotalDelay;
return 1;
} /* GIF_getInfo() */
//
// Unpack more chunk data for decoding
// returns 1 to signify more data available for this image
// 0 indicates there is no more data
//
static int GIFGetMoreData(GIFIMAGE *pPage)
{
int iDelta = (pPage->iLZWSize - pPage->iLZWOff);
unsigned char c = 1;
// move any existing data down
if (pPage->bEndOfFrame || iDelta >= (LZW_BUF_SIZE - MAX_CHUNK_SIZE) || iDelta <= 0)
return 1; // frame is finished or buffer is already full; no need to read more data
if (pPage->iLZWOff != 0)
{
// NB: memcpy() fails on some systems because the src and dest ptrs overlap
// so copy the bytes in a simple loop to avoid problems
for (int i=0; i<pPage->iLZWSize - pPage->iLZWOff; i++) {
pPage->ucLZW[i] = pPage->ucLZW[i + pPage->iLZWOff];
}
pPage->iLZWSize -= pPage->iLZWOff;
pPage->iLZWOff = 0;
}
while (c && pPage->GIFFile.iPos < pPage->GIFFile.iSize && pPage->iLZWSize < (LZW_BUF_SIZE-MAX_CHUNK_SIZE))
{
(*pPage->pfnRead)(&pPage->GIFFile, &c, 1); // current length
(*pPage->pfnRead)(&pPage->GIFFile, &pPage->ucLZW[pPage->iLZWSize], c);
pPage->iLZWSize += c;
}
if (c == 0) // end of frame
pPage->bEndOfFrame = 1;
return (c != 0 && pPage->GIFFile.iPos < pPage->GIFFile.iSize); // more data available?
} /* GIFGetMoreData() */
//
// Handle transparent pixels and disposal method
// Used only when a frame buffer is allocated
//
static void DrawNewPixels(GIFIMAGE *pPage, GIFDRAW *pDraw)
{
uint8_t *d, *s;
int x, iPitch = pPage->iCanvasWidth;
s = pDraw->pPixels;
d = (uint8_t*)&pPage->pFrameBuffer[pDraw->iX + (pDraw->y + pDraw->iY) * iPitch]; // dest pointer in our complete canvas buffer
if (pDraw->ucDisposalMethod == 2) // restore to background color
{
memset(d, pDraw->ucBackground, pDraw->iWidth);
}
// Apply the new pixels to the main image
if (pDraw->ucHasTransparency) // if transparency used
{
uint8_t c, ucTransparent = pDraw->ucTransparent;
for (x=0; x<pDraw->iWidth; x++)
{
c = *s++;
if (c != ucTransparent)
*d = c;
d++;
}
}
else
{
memcpy(d, s, pDraw->iWidth); // just overwrite the old pixels
}
} /* DrawNewPixels() */
//
// Convert current line of pixels through the palette
// to either RGB565 or RGB888 output
// Used only when a frame buffer has been allocated
//
static void ConvertNewPixels(GIFIMAGE *pPage, GIFDRAW *pDraw)
{
uint8_t *d, *s;
int x;
s = (uint8_t*)&pPage->pFrameBuffer[(pPage->iCanvasWidth * (pDraw->iY + pDraw->y)) + pDraw->iX];
d = (uint8_t*)&pPage->pFrameBuffer[pPage->iCanvasHeight * pPage->iCanvasWidth]; // point past bottom of frame buffer
if (pPage->ucPaletteType == GIF_PALETTE_RGB565_LE || pPage->ucPaletteType == GIF_PALETTE_RGB565_BE)
{
uint16_t *pPal, *pu16;
pPal = (uint16_t *)pDraw->pPalette;
pu16 = (uint16_t *)&pPage->pFrameBuffer[pPage->iCanvasHeight * pPage->iCanvasWidth];
for (x=0; x<pPage->iWidth; x++)
{
*pu16++ = pPal[*s++]; // convert to RGB565 pixels
}
}
else
{
uint8_t *pPal;
int pixel;
pPal = (uint8_t *)pDraw->pPalette;
for (x=0; x<pPage->iWidth; x++)
{
pixel = *s++;
*d++ = pPal[(pixel * 3) + 0]; // convert to RGB888 pixels
*d++ = pPal[(pixel * 3) + 1];
*d++ = pPal[(pixel * 3) + 2];
}
}
} /* ConvertNewPixels() */
//
// GIFMakePels
//
static void GIFMakePels(GIFIMAGE *pPage, unsigned int code)
{
int iPixCount;
unsigned short *giftabs;
unsigned char *buf, *s, *pEnd, *gifpels;
unsigned char ucNeedMore = 0;
/* Copy this string of sequential pixels to output buffer */
// iPixCount = 0;
s = pPage->ucFileBuf + FILE_BUF_SIZE; /* Pixels will come out in reversed order */
buf = pPage->ucLineBuf + (pPage->iWidth - pPage->iXCount);
giftabs = pPage->usGIFTable;
gifpels = &pPage->ucGIFPixels[PIXEL_LAST];
while (code < LINK_UNUSED)
{
if (s == pPage->ucFileBuf) /* Houston, we have a problem */
{
return; /* Exit with error */
}
*(--s) = gifpels[code];
code = giftabs[code];
}
iPixCount = (int)(intptr_t)(pPage->ucFileBuf + FILE_BUF_SIZE - s);
while (iPixCount && pPage->iYCount > 0)
{
if (pPage->iXCount > iPixCount) /* Pixels fit completely on the line */
{
// memcpy(buf, s, iPixCount);
// buf += iPixCount;
pEnd = buf + iPixCount;
while (buf < pEnd)
{
*buf++ = *s++;
}
pPage->iXCount -= iPixCount;
// iPixCount = 0;
if (ucNeedMore)
GIFGetMoreData(pPage); // check if we need to read more LZW data every 4 lines
return;
}
else /* Pixels cross into next line */
{
GIFDRAW gd;
pEnd = buf + pPage->iXCount;
while (buf < pEnd)
{
*buf++ = *s++;
}
iPixCount -= pPage->iXCount;
pPage->iXCount = pPage->iWidth; /* Reset pixel count */
// Prepare GIDRAW structure for callback
gd.iX = pPage->iX;
gd.iY = pPage->iY;
gd.iWidth = pPage->iWidth;
gd.iHeight = pPage->iHeight;
gd.pPixels = pPage->ucLineBuf;
gd.pPalette = (pPage->bUseLocalPalette) ? pPage->pLocalPalette : pPage->pPalette;
gd.pPalette24 = (uint8_t *)gd.pPalette; // just cast the pointer for RGB888
gd.ucIsGlobalPalette = pPage->bUseLocalPalette==1?0:1;
gd.y = pPage->iHeight - pPage->iYCount;
// Ugly logic to handle the interlaced line position, but it
// saves having to have another set of state variables
if (pPage->ucMap & 0x40) { // interlaced?
int height = pPage->iHeight-1;
if (gd.y > height / 2)
gd.y = gd.y * 2 - (height | 1);
else if (gd.y > height / 4)
gd.y = gd.y * 4 - ((height & ~1) | 2);
else if (gd.y > height / 8)
gd.y = gd.y * 8 - ((height & ~3) | 4);
else
gd.y = gd.y * 8;
}
gd.ucDisposalMethod = (pPage->ucGIFBits & 0x1c)>>2;
gd.ucTransparent = pPage->ucTransparent;
gd.ucHasTransparency = pPage->ucGIFBits & 1;
gd.ucBackground = pPage->ucBackground;
gd.pUser = pPage->pUser;
if (pPage->pFrameBuffer) // update the frame buffer
{
DrawNewPixels(pPage, &gd);
if (pPage->ucDrawType == GIF_DRAW_COOKED)
{
ConvertNewPixels(pPage, &gd); // prepare for output
gd.pPixels = (uint8_t*)&pPage->pFrameBuffer[pPage->iCanvasWidth * pPage->iCanvasHeight];
}
}
(*pPage->pfnDraw)(&gd); // callback to handle this line
pPage->iYCount--;
buf = pPage->ucLineBuf;
if ((pPage->iYCount & 3) == 0) // since we support only small images...
ucNeedMore = 1;
}
} /* while */
if (ucNeedMore)
GIFGetMoreData(pPage); // check if we need to read more LZW data every 4 lines
return;
} /* GIFMakePels() */
//
// Macro to extract a variable length code
//
#define GET_CODE if (bitnum > (REGISTER_WIDTH - codesize)) { pImage->iLZWOff += (bitnum >> 3); \
bitnum &= 7; ulBits = INTELLONG(&p[pImage->iLZWOff]); } \
code = (unsigned short) (ulBits >> bitnum); /* Read a 32-bit chunk */ \
code &= sMask; bitnum += codesize;
//
// Decode LZW into an image
//
static int DecodeLZW(GIFIMAGE *pImage, int iOptions)
{
int i, bitnum;
unsigned short oldcode, codesize, nextcode, nextlim;
unsigned short *giftabs, cc, eoi;
signed short sMask;
unsigned char *gifpels, *p;
// int iStripSize;
//unsigned char **index;
uint32_t ulBits;
unsigned short code;
(void)iOptions; // not used for now
// if output can be used for string table, do it faster
// if (bGIF && (OutPage->cBitsperpixel == 8 && ((OutPage->iWidth & 3) == 0)))
// return PILFastLZW(InPage, OutPage, bGIF, iOptions);
p = pImage->ucLZW; // un-chunked LZW data
sMask = 0xffff << (pImage->ucCodeStart + 1);
sMask = 0xffff - sMask;
cc = (sMask >> 1) + 1; /* Clear code */
eoi = cc + 1;
giftabs = pImage->usGIFTable;
gifpels = pImage->ucGIFPixels;
pImage->iYCount = pImage->iHeight; // count down the lines
pImage->iXCount = pImage->iWidth;
bitnum = 0;
pImage->iLZWOff = 0; // Offset into compressed data
GIFGetMoreData(pImage); // Read some data to start
// Initialize code table
// this part only needs to be initialized once
for (i = 0; i < cc; i++)
{
gifpels[PIXEL_FIRST + i] = gifpels[PIXEL_LAST + i] = (unsigned short) i;
giftabs[i] = LINK_END;
}
init_codetable:
codesize = pImage->ucCodeStart + 1;
sMask = 0xffff << (pImage->ucCodeStart + 1);
sMask = 0xffff - sMask;
nextcode = cc + 2;
nextlim = (unsigned short) ((1 << codesize));
// This part of the table needs to be reset multiple times
memset(&giftabs[cc], LINK_UNUSED, (4096 - cc)*sizeof(short));
ulBits = INTELLONG(&p[pImage->iLZWOff]); // start by reading 4 bytes of LZW data
GET_CODE
if (code == cc) // we just reset the dictionary, so get another code
{
GET_CODE
}
oldcode = code;
GIFMakePels(pImage, code); // first code is output as the first pixel
// Main decode loop
while (code != eoi && pImage->iYCount > 0) // && y < pImage->iHeight+1) /* Loop through all lines of the image (or strip) */
{
GET_CODE
if (code == cc) /* Clear code?, and not first code */
goto init_codetable;
if (code != eoi)
{
if (nextcode < nextlim) // for deferred cc case, don't let it overwrite the last entry (fff)
{
giftabs[nextcode] = oldcode;
gifpels[PIXEL_FIRST + nextcode] = gifpels[PIXEL_FIRST + oldcode];
if (giftabs[code] == LINK_UNUSED) /* Old code */
gifpels[PIXEL_LAST + nextcode] = gifpels[PIXEL_FIRST + oldcode];
else
gifpels[PIXEL_LAST + nextcode] = gifpels[PIXEL_FIRST + code];
}
nextcode++;
if (nextcode >= nextlim && codesize < 12)
{
codesize++;
nextlim <<= 1;
sMask = (sMask << 1) | 1;