aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/dpx.c
blob: 8e77c09bb17aec20b54cccee501a08e52984fc86 (plain) (blame)
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
/*
 * DPX (.dpx) image decoder
 * Copyright (c) 2009 Jimmy Christensen
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/avstring.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
#include "libavutil/imgutils.h"
#include "libavutil/timecode.h"
#include "bytestream.h"
#include "avcodec.h"
#include "internal.h"

enum DPX_TRC {
    DPX_TRC_USER_DEFINED       = 0,
    DPX_TRC_PRINTING_DENSITY   = 1,
    DPX_TRC_LINEAR             = 2,
    DPX_TRC_LOGARITHMIC        = 3,
    DPX_TRC_UNSPECIFIED_VIDEO  = 4,
    DPX_TRC_SMPTE_274          = 5,
    DPX_TRC_ITU_R_709_4        = 6,
    DPX_TRC_ITU_R_601_625      = 7,
    DPX_TRC_ITU_R_601_525      = 8,
    DPX_TRC_SMPTE_170          = 9,
    DPX_TRC_ITU_R_624_4_PAL    = 10,
    DPX_TRC_Z_LINEAR           = 11,
    DPX_TRC_Z_HOMOGENEOUS      = 12,
};

enum DPX_COL_SPEC {
    DPX_COL_SPEC_USER_DEFINED       = 0,
    DPX_COL_SPEC_PRINTING_DENSITY   = 1,
    /* 2 = N/A */
    /* 3 = N/A */
    DPX_COL_SPEC_UNSPECIFIED_VIDEO  = 4,
    DPX_COL_SPEC_SMPTE_274          = 5,
    DPX_COL_SPEC_ITU_R_709_4        = 6,
    DPX_COL_SPEC_ITU_R_601_625      = 7,
    DPX_COL_SPEC_ITU_R_601_525      = 8,
    DPX_COL_SPEC_SMPTE_170          = 9,
    DPX_COL_SPEC_ITU_R_624_4_PAL    = 10,
    /* 11 = N/A */
    /* 12 = N/A */
};

static unsigned int read16(const uint8_t **ptr, int is_big)
{
    unsigned int temp;
    if (is_big) {
        temp = AV_RB16(*ptr);
    } else {
        temp = AV_RL16(*ptr);
    }
    *ptr += 2;
    return temp;
}

static unsigned int read32(const uint8_t **ptr, int is_big)
{
    unsigned int temp;
    if (is_big) {
        temp = AV_RB32(*ptr);
    } else {
        temp = AV_RL32(*ptr);
    }
    *ptr += 4;
    return temp;
}

static uint16_t read10in32_gray(const uint8_t **ptr, uint32_t *lbuf,
                                int *n_datum, int is_big, int shift)
{
    uint16_t temp;

    if (*n_datum)
        (*n_datum)--;
    else {
        *lbuf = read32(ptr, is_big);
        *n_datum = 2;
    }

    temp = *lbuf >> shift & 0x3FF;
    *lbuf = *lbuf >> 10;

    return temp;
}

static uint16_t read10in32(const uint8_t **ptr, uint32_t *lbuf,
                           int *n_datum, int is_big, int shift)
{
    if (*n_datum)
        (*n_datum)--;
    else {
        *lbuf = read32(ptr, is_big);
        *n_datum = 2;
    }

    *lbuf = *lbuf << 10 | *lbuf >> shift & 0x3FFFFF;

    return *lbuf & 0x3FF;
}

static uint16_t read12in32(const uint8_t **ptr, uint32_t *lbuf,
                           int *n_datum, int is_big)
{
    if (*n_datum)
        (*n_datum)--;
    else {
        *lbuf = read32(ptr, is_big);
        *n_datum = 7;
    }

    switch (*n_datum){
    case 7: return *lbuf & 0xFFF;
    case 6: return (*lbuf >> 12) & 0xFFF;
    case 5: {
            uint32_t c = *lbuf >> 24;
            *lbuf = read32(ptr, is_big);
            c |= *lbuf << 8;
            return c & 0xFFF;
            }
    case 4: return (*lbuf >> 4) & 0xFFF;
    case 3: return (*lbuf >> 16) & 0xFFF;
    case 2: {
            uint32_t c = *lbuf >> 28;
            *lbuf = read32(ptr, is_big);
            c |= *lbuf << 4;
            return c & 0xFFF;
            }
    case 1: return (*lbuf >> 8) & 0xFFF;
    default: return *lbuf >> 20;
    }
}

static int decode_frame(AVCodecContext *avctx,
                        void *data,
                        int *got_frame,
                        AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size       = avpkt->size;
    AVFrame *const p = data;
    uint8_t *ptr[AV_NUM_DATA_POINTERS];
    uint32_t header_version, version = 0;
    char creator[101] = { 0 };
    char input_device[33] = { 0 };

    unsigned int offset;
    int magic_num, endian;
    int x, y, stride, i, j, ret;
    int w, h, bits_per_color, descriptor, elements, packing;
    int yuv, color_trc, color_spec;
    int encoding, need_align = 0, unpadded_10bit = 0;

    unsigned int rgbBuffer = 0;
    int n_datum = 0;

    if (avpkt->size <= 1634) {
        av_log(avctx, AV_LOG_ERROR, "Packet too small for DPX header\n");
        return AVERROR_INVALIDDATA;
    }

    magic_num = AV_RB32(buf);
    buf += 4;

    /* Check if the files "magic number" is "SDPX" which means it uses
     * big-endian or XPDS which is for little-endian files */
    if (magic_num == AV_RL32("SDPX")) {
        endian = 0;
    } else if (magic_num == AV_RB32("SDPX")) {
        endian = 1;
    } else {
        av_log(avctx, AV_LOG_ERROR, "DPX marker not found\n");
        return AVERROR_INVALIDDATA;
    }

    offset = read32(&buf, endian);
    if (avpkt->size <= offset) {
        av_log(avctx, AV_LOG_ERROR, "Invalid data start offset\n");
        return AVERROR_INVALIDDATA;
    }

    header_version = read32(&buf, 0);
    if (header_version == MKTAG('V','1','.','0'))
        version = 1;
    if (header_version == MKTAG('V','2','.','0'))
        version = 2;
    if (!version)
        av_log(avctx, AV_LOG_WARNING, "Unknown header format version %s.\n",
               av_fourcc2str(header_version));

    // Check encryption
    buf = avpkt->data + 660;
    ret = read32(&buf, endian);
    if (ret != 0xFFFFFFFF) {
        avpriv_report_missing_feature(avctx, "Encryption");
        av_log(avctx, AV_LOG_WARNING, "The image is encrypted and may "
               "not properly decode.\n");
    }

    // Need to end in 0x304 offset from start of file
    buf = avpkt->data + 0x304;
    w = read32(&buf, endian);
    h = read32(&buf, endian);

    if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
        return ret;

    // Need to end in 0x320 to read the descriptor
    buf += 20;
    descriptor = buf[0];
    color_trc = buf[1];
    color_spec = buf[2];

    // Need to end in 0x323 to read the bits per color
    buf += 3;
    avctx->bits_per_raw_sample =
    bits_per_color = buf[0];
    buf++;
    packing = read16(&buf, endian);
    encoding = read16(&buf, endian);

    if (encoding) {
        avpriv_report_missing_feature(avctx, "Encoding %d", encoding);
        return AVERROR_PATCHWELCOME;
    }

    if (bits_per_color > 32)
        return AVERROR_INVALIDDATA;

    buf += 820;
    avctx->sample_aspect_ratio.num = read32(&buf, endian);
    avctx->sample_aspect_ratio.den = read32(&buf, endian);
    if (avctx->sample_aspect_ratio.num > 0 && avctx->sample_aspect_ratio.den > 0)
        av_reduce(&avctx->sample_aspect_ratio.num, &avctx->sample_aspect_ratio.den,
                   avctx->sample_aspect_ratio.num,  avctx->sample_aspect_ratio.den,
                  0x10000);
    else
        avctx->sample_aspect_ratio = (AVRational){ 0, 1 };

    /* preferred frame rate from Motion-picture film header */
    if (offset >= 1724 + 4) {
        buf = avpkt->data + 1724;
        i = read32(&buf, endian);
        if(i && i != 0xFFFFFFFF) {
            AVRational q = av_d2q(av_int2float(i), 4096);
            if (q.num > 0 && q.den > 0)
                avctx->framerate = q;
        }
    }

    /* alternative frame rate from television header */
    if (offset >= 1940 + 4 &&
        !(avctx->framerate.num && avctx->framerate.den)) {
        buf = avpkt->data + 1940;
        i = read32(&buf, endian);
        if(i && i != 0xFFFFFFFF) {
            AVRational q = av_d2q(av_int2float(i), 4096);
            if (q.num > 0 && q.den > 0)
                avctx->framerate = q;
        }
    }

    /* SMPTE TC from television header */
    if (offset >= 1920 + 4) {
        uint32_t tc;
        uint32_t *tc_sd;
        char tcbuf[AV_TIMECODE_STR_SIZE];

        buf = avpkt->data + 1920;
        // read32 to native endian, av_bswap32 to opposite of native for
        // compatibility with av_timecode_make_smpte_tc_string2 etc
        tc = av_bswap32(read32(&buf, endian));

        if (i != 0xFFFFFFFF) {
            AVFrameSideData *tcside =
                av_frame_new_side_data(p, AV_FRAME_DATA_S12M_TIMECODE,
                                       sizeof(uint32_t) * 4);
            if (!tcside)
                return AVERROR(ENOMEM);

            tc_sd = (uint32_t*)tcside->data;
            tc_sd[0] = 1;
            tc_sd[1] = tc;

            av_timecode_make_smpte_tc_string2(tcbuf, avctx->framerate,
                                              tc_sd[1], 0, 0);
            av_dict_set(&p->metadata, "timecode", tcbuf, 0);
        }
    }

    /* color range from television header */
    if (offset >= 1964 + 4) {
        buf = avpkt->data + 1952;
        i = read32(&buf, endian);

        buf = avpkt->data + 1964;
        j = read32(&buf, endian);

        if (i != 0xFFFFFFFF && j != 0xFFFFFFFF) {
            float minCV, maxCV;
            minCV = av_int2float(i);
            maxCV = av_int2float(j);
            if (bits_per_color >= 1 &&
                minCV == 0.0f && maxCV == ((1<<bits_per_color) - 1)) {
                avctx->color_range = AVCOL_RANGE_JPEG;
            } else if (bits_per_color >= 8 &&
                       minCV == (1  <<(bits_per_color - 4)) &&
                       maxCV == (235<<(bits_per_color - 8))) {
                avctx->color_range = AVCOL_RANGE_MPEG;
            }
        }
    }

    switch (descriptor) {
    case 1:  // R
    case 2:  // G
    case 3:  // B
    case 4:  // A
    case 6:  // Y
        elements = 1;
        yuv = 1;
        break;
    case 50: // RGB
        elements = 3;
        yuv = 0;
        break;
    case 52: // ABGR
    case 51: // RGBA
        elements = 4;
        yuv = 0;
        break;
    case 100: // UYVY422
        elements = 2;
        yuv = 1;
        break;
    case 102: // UYV444
        elements = 3;
        yuv = 1;
        break;
    case 103: // UYVA4444
        elements = 4;
        yuv = 1;
        break;
    default:
        avpriv_report_missing_feature(avctx, "Descriptor %d", descriptor);
        return AVERROR_PATCHWELCOME;
    }

    switch (bits_per_color) {
    case 8:
        stride = avctx->width * elements;
        break;
    case 10:
        if (!packing) {
            av_log(avctx, AV_LOG_ERROR, "Packing to 32bit required\n");
            return -1;
        }
        stride = (avctx->width * elements + 2) / 3 * 4;
        break;
    case 12:
        stride = avctx->width * elements;
        if (packing) {
            stride *= 2;
        } else {
            stride *= 3;
            if (stride % 8) {
                stride /= 8;
                stride++;
                stride *= 8;
            }
            stride /= 2;
        }
        break;
    case 16:
        stride = 2 * avctx->width * elements;
        break;
    case 32:
        stride = 4 * avctx->width * elements;
        break;
    case 1:
    case 64:
        avpriv_report_missing_feature(avctx, "Depth %d", bits_per_color);
        return AVERROR_PATCHWELCOME;
    default:
        return AVERROR_INVALIDDATA;
    }

    switch (color_trc) {
    case DPX_TRC_LINEAR:
        avctx->color_trc = AVCOL_TRC_LINEAR;
        break;
    case DPX_TRC_SMPTE_274:
    case DPX_TRC_ITU_R_709_4:
        avctx->color_trc = AVCOL_TRC_BT709;
        break;
    case DPX_TRC_ITU_R_601_625:
    case DPX_TRC_ITU_R_601_525:
    case DPX_TRC_SMPTE_170:
        avctx->color_trc = AVCOL_TRC_SMPTE170M;
        break;
    case DPX_TRC_ITU_R_624_4_PAL:
        avctx->color_trc = AVCOL_TRC_GAMMA28;
        break;
    case DPX_TRC_USER_DEFINED:
    case DPX_TRC_UNSPECIFIED_VIDEO:
        /* Nothing to do */
        break;
    default:
        av_log(avctx, AV_LOG_VERBOSE, "Cannot map DPX transfer characteristic "
            "%d to color_trc.\n", color_trc);
        break;
    }

    switch (color_spec) {
    case DPX_COL_SPEC_SMPTE_274:
    case DPX_COL_SPEC_ITU_R_709_4:
        avctx->color_primaries = AVCOL_PRI_BT709;
        break;
    case DPX_COL_SPEC_ITU_R_601_625:
    case DPX_COL_SPEC_ITU_R_624_4_PAL:
        avctx->color_primaries = AVCOL_PRI_BT470BG;
        break;
    case DPX_COL_SPEC_ITU_R_601_525:
    case DPX_COL_SPEC_SMPTE_170:
        avctx->color_primaries = AVCOL_PRI_SMPTE170M;
        break;
    case DPX_COL_SPEC_USER_DEFINED:
    case DPX_COL_SPEC_UNSPECIFIED_VIDEO:
        /* Nothing to do */
        break;
    default:
        av_log(avctx, AV_LOG_VERBOSE, "Cannot map DPX color specification "
            "%d to color_primaries.\n", color_spec);
        break;
    }

    if (yuv) {
        switch (color_spec) {
        case DPX_COL_SPEC_SMPTE_274:
        case DPX_COL_SPEC_ITU_R_709_4:
            avctx->colorspace = AVCOL_SPC_BT709;
            break;
        case DPX_COL_SPEC_ITU_R_601_625:
        case DPX_COL_SPEC_ITU_R_624_4_PAL:
            avctx->colorspace = AVCOL_SPC_BT470BG;
            break;
        case DPX_COL_SPEC_ITU_R_601_525:
        case DPX_COL_SPEC_SMPTE_170:
            avctx->colorspace = AVCOL_SPC_SMPTE170M;
            break;
        case DPX_COL_SPEC_USER_DEFINED:
        case DPX_COL_SPEC_UNSPECIFIED_VIDEO:
            /* Nothing to do */
            break;
        default:
            av_log(avctx, AV_LOG_INFO, "Cannot map DPX color specification "
                "%d to colorspace.\n", color_spec);
            break;
        }
    } else {
        avctx->colorspace = AVCOL_SPC_RGB;
    }

    // Table 3c: Runs will always break at scan line boundaries. Packing
    // will always break to the next 32-bit word at scan-line boundaries.
    // Unfortunately, the encoder produced invalid files, so attempt
    // to detect it
    need_align = FFALIGN(stride, 4);
    if (need_align*avctx->height + (int64_t)offset > avpkt->size) {
        // Alignment seems unappliable, try without
        if (stride*avctx->height + (int64_t)offset > avpkt->size) {
            av_log(avctx, AV_LOG_ERROR, "Overread buffer. Invalid header?\n");
            return AVERROR_INVALIDDATA;
        } else {
            av_log(avctx, AV_LOG_INFO, "Decoding DPX without scanline "
                   "alignment.\n");
            need_align = 0;
        }
    } else {
        need_align -= stride;
        stride = FFALIGN(stride, 4);
    }

    switch (1000 * descriptor + 10 * bits_per_color + endian) {
    case 1081:
    case 1080:
    case 2081:
    case 2080:
    case 3081:
    case 3080:
    case 4081:
    case 4080:
    case 6081:
    case 6080:
        avctx->pix_fmt = AV_PIX_FMT_GRAY8;
        break;
    case 6121:
    case 6120:
        avctx->pix_fmt = AV_PIX_FMT_GRAY12;
        break;
    case 1320:
    case 2320:
    case 3320:
    case 4320:
    case 6320:
        avctx->pix_fmt = AV_PIX_FMT_GRAYF32LE;
        break;
    case 1321:
    case 2321:
    case 3321:
    case 4321:
    case 6321:
        avctx->pix_fmt = AV_PIX_FMT_GRAYF32BE;
        break;
    case 50081:
    case 50080:
        avctx->pix_fmt = AV_PIX_FMT_RGB24;
        break;
    case 52081:
    case 52080:
        avctx->pix_fmt = AV_PIX_FMT_ABGR;
        break;
    case 51081:
    case 51080:
        avctx->pix_fmt = AV_PIX_FMT_RGBA;
        break;
    case 50100:
    case 50101:
        avctx->pix_fmt = AV_PIX_FMT_GBRP10;
        break;
    case 51100:
    case 51101:
        avctx->pix_fmt = AV_PIX_FMT_GBRAP10;
        break;
    case 50120:
    case 50121:
        avctx->pix_fmt = AV_PIX_FMT_GBRP12;
        break;
    case 51120:
    case 51121:
        avctx->pix_fmt = AV_PIX_FMT_GBRAP12;
        break;
    case 6100:
    case 6101:
        avctx->pix_fmt = AV_PIX_FMT_GRAY10;
        break;
    case 6161:
        avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
        break;
    case 6160:
        avctx->pix_fmt = AV_PIX_FMT_GRAY16LE;
        break;
    case 50161:
        avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
        break;
    case 50160:
        avctx->pix_fmt = AV_PIX_FMT_RGB48LE;
        break;
    case 51161:
        avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
        break;
    case 51160:
        avctx->pix_fmt = AV_PIX_FMT_RGBA64LE;
        break;
    case 50320:
        avctx->pix_fmt = AV_PIX_FMT_GBRPF32LE;
        break;
    case 50321:
        avctx->pix_fmt = AV_PIX_FMT_GBRPF32BE;
        break;
    case 51320:
        avctx->pix_fmt = AV_PIX_FMT_GBRAPF32LE;
        break;
    case 51321:
        avctx->pix_fmt = AV_PIX_FMT_GBRAPF32BE;
        break;
    case 100081:
        avctx->pix_fmt = AV_PIX_FMT_UYVY422;
        break;
    case 102081:
        avctx->pix_fmt = AV_PIX_FMT_YUV444P;
        break;
    case 103081:
        avctx->pix_fmt = AV_PIX_FMT_YUVA444P;
        break;
    default:
        av_log(avctx, AV_LOG_ERROR, "Unsupported format %d\n",
               1000 * descriptor + 10 * bits_per_color + endian);
        return AVERROR_PATCHWELCOME;
    }

    ff_set_sar(avctx, avctx->sample_aspect_ratio);

    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
        return ret;

    av_strlcpy(creator, avpkt->data + 160, 100);
    creator[100] = '\0';
    av_dict_set(&p->metadata, "Creator", creator, 0);

    av_strlcpy(input_device, avpkt->data + 1556, 32);
    input_device[32] = '\0';
    av_dict_set(&p->metadata, "Input Device", input_device, 0);

    // Some devices do not pad 10bit samples to whole 32bit words per row
    if (!memcmp(input_device, "Scanity", 7) ||
        !memcmp(creator, "Lasergraphics Inc.", 18)) {
        unpadded_10bit = 1;
    }

    // Move pointer to offset from start of file
    buf =  avpkt->data + offset;

    for (i=0; i<AV_NUM_DATA_POINTERS; i++)
        ptr[i] = p->data[i];

    switch (bits_per_color) {
    case 10:
        for (x = 0; x < avctx->height; x++) {
            uint16_t *dst[4] = {(uint16_t*)ptr[0],
                                (uint16_t*)ptr[1],
                                (uint16_t*)ptr[2],
                                (uint16_t*)ptr[3]};
            int shift = elements > 1 ? packing == 1 ? 22 : 20 : packing == 1 ? 2 : 0;
            for (y = 0; y < avctx->width; y++) {
                if (elements >= 3)
                    *dst[2]++ = read10in32(&buf, &rgbBuffer,
                                           &n_datum, endian, shift);
                if (elements == 1)
                    *dst[0]++ = read10in32_gray(&buf, &rgbBuffer,
                                                &n_datum, endian, shift);
                else
                    *dst[0]++ = read10in32(&buf, &rgbBuffer,
                                           &n_datum, endian, shift);
                if (elements >= 2)
                    *dst[1]++ = read10in32(&buf, &rgbBuffer,
                                           &n_datum, endian, shift);
                if (elements == 4)
                    *dst[3]++ =
                    read10in32(&buf, &rgbBuffer,
                               &n_datum, endian, shift);
            }
            if (!unpadded_10bit)
                n_datum = 0;
            for (i = 0; i < elements; i++)
                ptr[i] += p->linesize[i];
        }
        break;
    case 12:
        for (x = 0; x < avctx->height; x++) {
            uint16_t *dst[4] = {(uint16_t*)ptr[0],
                                (uint16_t*)ptr[1],
                                (uint16_t*)ptr[2],
                                (uint16_t*)ptr[3]};
            int shift = packing == 1 ? 4 : 0;
            for (y = 0; y < avctx->width; y++) {
                if (packing) {
                    if (elements >= 3)
                        *dst[2]++ = read16(&buf, endian) >> shift & 0xFFF;
                    *dst[0]++ = read16(&buf, endian) >> shift & 0xFFF;
                    if (elements >= 2)
                        *dst[1]++ = read16(&buf, endian) >> shift & 0xFFF;
                    if (elements == 4)
                        *dst[3]++ = read16(&buf, endian) >> shift & 0xFFF;
                } else {
                    if (elements >= 3)
                        *dst[2]++ = read12in32(&buf, &rgbBuffer,
                                               &n_datum, endian);
                    *dst[0]++ = read12in32(&buf, &rgbBuffer,
                                           &n_datum, endian);
                    if (elements >= 2)
                        *dst[1]++ = read12in32(&buf, &rgbBuffer,
                                               &n_datum, endian);
                    if (elements == 4)
                        *dst[3]++ = read12in32(&buf, &rgbBuffer,
                                               &n_datum, endian);
                }
            }
            n_datum = 0;
            for (i = 0; i < elements; i++)
                ptr[i] += p->linesize[i];
            // Jump to next aligned position
            buf += need_align;
        }
        break;
    case 32:
        if (elements == 1) {
            av_image_copy_plane(ptr[0], p->linesize[0],
                                buf, stride,
                                elements * avctx->width * 4, avctx->height);
        } else {
            for (y = 0; y < avctx->height; y++) {
                ptr[0] = p->data[0] + y * p->linesize[0];
                ptr[1] = p->data[1] + y * p->linesize[1];
                ptr[2] = p->data[2] + y * p->linesize[2];
                ptr[3] = p->data[3] + y * p->linesize[3];
                for (x = 0; x < avctx->width; x++) {
                    AV_WN32(ptr[2], AV_RN32(buf));
                    AV_WN32(ptr[0], AV_RN32(buf + 4));
                    AV_WN32(ptr[1], AV_RN32(buf + 8));
                    if (avctx->pix_fmt == AV_PIX_FMT_GBRAPF32BE ||
                        avctx->pix_fmt == AV_PIX_FMT_GBRAPF32LE) {
                        AV_WN32(ptr[3], AV_RN32(buf + 12));
                        buf += 4;
                        ptr[3] += 4;
                    }

                    buf += 12;
                    ptr[2] += 4;
                    ptr[0] += 4;
                    ptr[1] += 4;
                }
            }
        }
        break;
    case 16:
        elements *= 2;
    case 8:
        if (   avctx->pix_fmt == AV_PIX_FMT_YUVA444P
            || avctx->pix_fmt == AV_PIX_FMT_YUV444P) {
            for (x = 0; x < avctx->height; x++) {
                ptr[0] = p->data[0] + x * p->linesize[0];
                ptr[1] = p->data[1] + x * p->linesize[1];
                ptr[2] = p->data[2] + x * p->linesize[2];
                ptr[3] = p->data[3] + x * p->linesize[3];
                for (y = 0; y < avctx->width; y++) {
                    *ptr[1]++ = *buf++;
                    *ptr[0]++ = *buf++;
                    *ptr[2]++ = *buf++;
                    if (avctx->pix_fmt == AV_PIX_FMT_YUVA444P)
                        *ptr[3]++ = *buf++;
                }
            }
        } else {
        av_image_copy_plane(ptr[0], p->linesize[0],
                            buf, stride,
                            elements * avctx->width, avctx->height);
        }
        break;
    }

    *got_frame = 1;

    return buf_size;
}

const AVCodec ff_dpx_decoder = {
    .name           = "dpx",
    .long_name      = NULL_IF_CONFIG_SMALL("DPX (Digital Picture Exchange) image"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_DPX,
    .decode         = decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};