xref: /third_party/ffmpeg/libavcodec/cbs_av1.c (revision cabdff1a)
1/*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19#include "libavutil/avassert.h"
20#include "libavutil/opt.h"
21#include "libavutil/pixfmt.h"
22
23#include "avcodec.h"
24#include "cbs.h"
25#include "cbs_internal.h"
26#include "cbs_av1.h"
27
28
29static int cbs_av1_read_uvlc(CodedBitstreamContext *ctx, GetBitContext *gbc,
30                             const char *name, uint32_t *write_to,
31                             uint32_t range_min, uint32_t range_max)
32{
33    uint32_t zeroes, bits_value, value;
34    int position;
35
36    if (ctx->trace_enable)
37        position = get_bits_count(gbc);
38
39    zeroes = 0;
40    while (1) {
41        if (get_bits_left(gbc) < 1) {
42            av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid uvlc code at "
43                   "%s: bitstream ended.\n", name);
44            return AVERROR_INVALIDDATA;
45        }
46
47        if (get_bits1(gbc))
48            break;
49        ++zeroes;
50    }
51
52    if (zeroes >= 32) {
53        value = MAX_UINT_BITS(32);
54    } else {
55        if (get_bits_left(gbc) < zeroes) {
56            av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid uvlc code at "
57                   "%s: bitstream ended.\n", name);
58            return AVERROR_INVALIDDATA;
59        }
60
61        bits_value = get_bits_long(gbc, zeroes);
62        value = bits_value + (UINT32_C(1) << zeroes) - 1;
63    }
64
65    if (ctx->trace_enable) {
66        char bits[65];
67        int i, j, k;
68
69        if (zeroes >= 32) {
70            while (zeroes > 32) {
71                k = FFMIN(zeroes - 32, 32);
72                for (i = 0; i < k; i++)
73                    bits[i] = '0';
74                bits[i] = 0;
75                ff_cbs_trace_syntax_element(ctx, position, name,
76                                            NULL, bits, 0);
77                zeroes -= k;
78                position += k;
79            }
80        }
81
82        for (i = 0; i < zeroes; i++)
83            bits[i] = '0';
84        bits[i++] = '1';
85
86        if (zeroes < 32) {
87            for (j = 0; j < zeroes; j++)
88                bits[i++] = (bits_value >> (zeroes - j - 1) & 1) ? '1' : '0';
89        }
90
91        bits[i] = 0;
92        ff_cbs_trace_syntax_element(ctx, position, name,
93                                    NULL, bits, value);
94    }
95
96    if (value < range_min || value > range_max) {
97        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
98               "%"PRIu32", but must be in [%"PRIu32",%"PRIu32"].\n",
99               name, value, range_min, range_max);
100        return AVERROR_INVALIDDATA;
101    }
102
103    *write_to = value;
104    return 0;
105}
106
107static int cbs_av1_write_uvlc(CodedBitstreamContext *ctx, PutBitContext *pbc,
108                              const char *name, uint32_t value,
109                              uint32_t range_min, uint32_t range_max)
110{
111    uint32_t v;
112    int position, zeroes;
113
114    if (value < range_min || value > range_max) {
115        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
116               "%"PRIu32", but must be in [%"PRIu32",%"PRIu32"].\n",
117               name, value, range_min, range_max);
118        return AVERROR_INVALIDDATA;
119    }
120
121    if (ctx->trace_enable)
122        position = put_bits_count(pbc);
123
124    zeroes = av_log2(value + 1);
125    v = value - (1U << zeroes) + 1;
126    put_bits(pbc, zeroes, 0);
127    put_bits(pbc, 1, 1);
128    put_bits(pbc, zeroes, v);
129
130    if (ctx->trace_enable) {
131        char bits[65];
132        int i, j;
133        i = 0;
134        for (j = 0; j < zeroes; j++)
135            bits[i++] = '0';
136        bits[i++] = '1';
137        for (j = 0; j < zeroes; j++)
138            bits[i++] = (v >> (zeroes - j - 1) & 1) ? '1' : '0';
139        bits[i++] = 0;
140        ff_cbs_trace_syntax_element(ctx, position, name, NULL,
141                                    bits, value);
142    }
143
144    return 0;
145}
146
147static int cbs_av1_read_leb128(CodedBitstreamContext *ctx, GetBitContext *gbc,
148                               const char *name, uint64_t *write_to)
149{
150    uint64_t value;
151    int position, err, i;
152
153    if (ctx->trace_enable)
154        position = get_bits_count(gbc);
155
156    value = 0;
157    for (i = 0; i < 8; i++) {
158        int subscript[2] = { 1, i };
159        uint32_t byte;
160        err = ff_cbs_read_unsigned(ctx, gbc, 8, "leb128_byte[i]", subscript,
161                                   &byte, 0x00, 0xff);
162        if (err < 0)
163            return err;
164
165        value |= (uint64_t)(byte & 0x7f) << (i * 7);
166        if (!(byte & 0x80))
167            break;
168    }
169
170    if (value > UINT32_MAX)
171        return AVERROR_INVALIDDATA;
172
173    if (ctx->trace_enable)
174        ff_cbs_trace_syntax_element(ctx, position, name, NULL, "", value);
175
176    *write_to = value;
177    return 0;
178}
179
180static int cbs_av1_write_leb128(CodedBitstreamContext *ctx, PutBitContext *pbc,
181                                const char *name, uint64_t value)
182{
183    int position, err, len, i;
184    uint8_t byte;
185
186    len = (av_log2(value) + 7) / 7;
187
188    if (ctx->trace_enable)
189        position = put_bits_count(pbc);
190
191    for (i = 0; i < len; i++) {
192        int subscript[2] = { 1, i };
193
194        byte = value >> (7 * i) & 0x7f;
195        if (i < len - 1)
196            byte |= 0x80;
197
198        err = ff_cbs_write_unsigned(ctx, pbc, 8, "leb128_byte[i]", subscript,
199                                    byte, 0x00, 0xff);
200        if (err < 0)
201            return err;
202    }
203
204    if (ctx->trace_enable)
205        ff_cbs_trace_syntax_element(ctx, position, name, NULL, "", value);
206
207    return 0;
208}
209
210static int cbs_av1_read_ns(CodedBitstreamContext *ctx, GetBitContext *gbc,
211                           uint32_t n, const char *name,
212                           const int *subscripts, uint32_t *write_to)
213{
214    uint32_t m, v, extra_bit, value;
215    int position, w;
216
217    av_assert0(n > 0);
218
219    if (ctx->trace_enable)
220        position = get_bits_count(gbc);
221
222    w = av_log2(n) + 1;
223    m = (1 << w) - n;
224
225    if (get_bits_left(gbc) < w) {
226        av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid non-symmetric value at "
227               "%s: bitstream ended.\n", name);
228        return AVERROR_INVALIDDATA;
229    }
230
231    if (w - 1 > 0)
232        v = get_bits(gbc, w - 1);
233    else
234        v = 0;
235
236    if (v < m) {
237        value = v;
238    } else {
239        extra_bit = get_bits1(gbc);
240        value = (v << 1) - m + extra_bit;
241    }
242
243    if (ctx->trace_enable) {
244        char bits[33];
245        int i;
246        for (i = 0; i < w - 1; i++)
247            bits[i] = (v >> i & 1) ? '1' : '0';
248        if (v >= m)
249            bits[i++] = extra_bit ? '1' : '0';
250        bits[i] = 0;
251
252        ff_cbs_trace_syntax_element(ctx, position,
253                                    name, subscripts, bits, value);
254    }
255
256    *write_to = value;
257    return 0;
258}
259
260static int cbs_av1_write_ns(CodedBitstreamContext *ctx, PutBitContext *pbc,
261                            uint32_t n, const char *name,
262                            const int *subscripts, uint32_t value)
263{
264    uint32_t w, m, v, extra_bit;
265    int position;
266
267    if (value > n) {
268        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
269               "%"PRIu32", but must be in [0,%"PRIu32"].\n",
270               name, value, n);
271        return AVERROR_INVALIDDATA;
272    }
273
274    if (ctx->trace_enable)
275        position = put_bits_count(pbc);
276
277    w = av_log2(n) + 1;
278    m = (1 << w) - n;
279
280    if (put_bits_left(pbc) < w)
281        return AVERROR(ENOSPC);
282
283    if (value < m) {
284        v = value;
285        put_bits(pbc, w - 1, v);
286    } else {
287        v = m + ((value - m) >> 1);
288        extra_bit = (value - m) & 1;
289        put_bits(pbc, w - 1, v);
290        put_bits(pbc, 1, extra_bit);
291    }
292
293    if (ctx->trace_enable) {
294        char bits[33];
295        int i;
296        for (i = 0; i < w - 1; i++)
297            bits[i] = (v >> i & 1) ? '1' : '0';
298        if (value >= m)
299            bits[i++] = extra_bit ? '1' : '0';
300        bits[i] = 0;
301
302        ff_cbs_trace_syntax_element(ctx, position,
303                                    name, subscripts, bits, value);
304    }
305
306    return 0;
307}
308
309static int cbs_av1_read_increment(CodedBitstreamContext *ctx, GetBitContext *gbc,
310                                  uint32_t range_min, uint32_t range_max,
311                                  const char *name, uint32_t *write_to)
312{
313    uint32_t value;
314    int position, i;
315    char bits[33];
316
317    av_assert0(range_min <= range_max && range_max - range_min < sizeof(bits) - 1);
318    if (ctx->trace_enable)
319        position = get_bits_count(gbc);
320
321    for (i = 0, value = range_min; value < range_max;) {
322        if (get_bits_left(gbc) < 1) {
323            av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid increment value at "
324                   "%s: bitstream ended.\n", name);
325            return AVERROR_INVALIDDATA;
326        }
327        if (get_bits1(gbc)) {
328            bits[i++] = '1';
329            ++value;
330        } else {
331            bits[i++] = '0';
332            break;
333        }
334    }
335
336    if (ctx->trace_enable) {
337        bits[i] = 0;
338        ff_cbs_trace_syntax_element(ctx, position,
339                                    name, NULL, bits, value);
340    }
341
342    *write_to = value;
343    return 0;
344}
345
346static int cbs_av1_write_increment(CodedBitstreamContext *ctx, PutBitContext *pbc,
347                                   uint32_t range_min, uint32_t range_max,
348                                   const char *name, uint32_t value)
349{
350    int len;
351
352    av_assert0(range_min <= range_max && range_max - range_min < 32);
353    if (value < range_min || value > range_max) {
354        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
355               "%"PRIu32", but must be in [%"PRIu32",%"PRIu32"].\n",
356               name, value, range_min, range_max);
357        return AVERROR_INVALIDDATA;
358    }
359
360    if (value == range_max)
361        len = range_max - range_min;
362    else
363        len = value - range_min + 1;
364    if (put_bits_left(pbc) < len)
365        return AVERROR(ENOSPC);
366
367    if (ctx->trace_enable) {
368        char bits[33];
369        int i;
370        for (i = 0; i < len; i++) {
371            if (range_min + i == value)
372                bits[i] = '0';
373            else
374                bits[i] = '1';
375        }
376        bits[i] = 0;
377        ff_cbs_trace_syntax_element(ctx, put_bits_count(pbc),
378                                    name, NULL, bits, value);
379    }
380
381    if (len > 0)
382        put_bits(pbc, len, (1U << len) - 1 - (value != range_max));
383
384    return 0;
385}
386
387static int cbs_av1_read_subexp(CodedBitstreamContext *ctx, GetBitContext *gbc,
388                               uint32_t range_max, const char *name,
389                               const int *subscripts, uint32_t *write_to)
390{
391    uint32_t value;
392    int position, err;
393    uint32_t max_len, len, range_offset, range_bits;
394
395    if (ctx->trace_enable)
396        position = get_bits_count(gbc);
397
398    av_assert0(range_max > 0);
399    max_len = av_log2(range_max - 1) - 3;
400
401    err = cbs_av1_read_increment(ctx, gbc, 0, max_len,
402                                 "subexp_more_bits", &len);
403    if (err < 0)
404        return err;
405
406    if (len) {
407        range_bits   = 2 + len;
408        range_offset = 1 << range_bits;
409    } else {
410        range_bits   = 3;
411        range_offset = 0;
412    }
413
414    if (len < max_len) {
415        err = ff_cbs_read_unsigned(ctx, gbc, range_bits,
416                                   "subexp_bits", NULL, &value,
417                                   0, MAX_UINT_BITS(range_bits));
418        if (err < 0)
419            return err;
420
421    } else {
422        err = cbs_av1_read_ns(ctx, gbc, range_max - range_offset,
423                              "subexp_final_bits", NULL, &value);
424        if (err < 0)
425            return err;
426    }
427    value += range_offset;
428
429    if (ctx->trace_enable)
430        ff_cbs_trace_syntax_element(ctx, position,
431                                    name, subscripts, "", value);
432
433    *write_to = value;
434    return err;
435}
436
437static int cbs_av1_write_subexp(CodedBitstreamContext *ctx, PutBitContext *pbc,
438                                uint32_t range_max, const char *name,
439                                const int *subscripts, uint32_t value)
440{
441    int position, err;
442    uint32_t max_len, len, range_offset, range_bits;
443
444    if (value > range_max) {
445        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
446               "%"PRIu32", but must be in [0,%"PRIu32"].\n",
447               name, value, range_max);
448        return AVERROR_INVALIDDATA;
449    }
450
451    if (ctx->trace_enable)
452        position = put_bits_count(pbc);
453
454    av_assert0(range_max > 0);
455    max_len = av_log2(range_max - 1) - 3;
456
457    if (value < 8) {
458        range_bits   = 3;
459        range_offset = 0;
460        len = 0;
461    } else {
462        range_bits = av_log2(value);
463        len = range_bits - 2;
464        if (len > max_len) {
465            // The top bin is combined with the one below it.
466            av_assert0(len == max_len + 1);
467            --range_bits;
468            len = max_len;
469        }
470        range_offset = 1 << range_bits;
471    }
472
473    err = cbs_av1_write_increment(ctx, pbc, 0, max_len,
474                                  "subexp_more_bits", len);
475    if (err < 0)
476        return err;
477
478    if (len < max_len) {
479        err = ff_cbs_write_unsigned(ctx, pbc, range_bits,
480                                    "subexp_bits", NULL,
481                                    value - range_offset,
482                                    0, MAX_UINT_BITS(range_bits));
483        if (err < 0)
484            return err;
485
486    } else {
487        err = cbs_av1_write_ns(ctx, pbc, range_max - range_offset,
488                               "subexp_final_bits", NULL,
489                               value - range_offset);
490        if (err < 0)
491            return err;
492    }
493
494    if (ctx->trace_enable)
495        ff_cbs_trace_syntax_element(ctx, position,
496                                    name, subscripts, "", value);
497
498    return err;
499}
500
501
502static int cbs_av1_tile_log2(int blksize, int target)
503{
504    int k;
505    for (k = 0; (blksize << k) < target; k++);
506    return k;
507}
508
509static int cbs_av1_get_relative_dist(const AV1RawSequenceHeader *seq,
510                                     unsigned int a, unsigned int b)
511{
512    unsigned int diff, m;
513    if (!seq->enable_order_hint)
514        return 0;
515    diff = a - b;
516    m = 1 << seq->order_hint_bits_minus_1;
517    diff = (diff & (m - 1)) - (diff & m);
518    return diff;
519}
520
521static size_t cbs_av1_get_payload_bytes_left(GetBitContext *gbc)
522{
523    GetBitContext tmp = *gbc;
524    size_t size = 0;
525    for (int i = 0; get_bits_left(&tmp) >= 8; i++) {
526        if (get_bits(&tmp, 8))
527            size = i;
528    }
529    return size;
530}
531
532
533#define HEADER(name) do { \
534        ff_cbs_trace_header(ctx, name); \
535    } while (0)
536
537#define CHECK(call) do { \
538        err = (call); \
539        if (err < 0) \
540            return err; \
541    } while (0)
542
543#define FUNC_NAME(rw, codec, name) cbs_ ## codec ## _ ## rw ## _ ## name
544#define FUNC_AV1(rw, name) FUNC_NAME(rw, av1, name)
545#define FUNC(name) FUNC_AV1(READWRITE, name)
546
547#define SUBSCRIPTS(subs, ...) (subs > 0 ? ((int[subs + 1]){ subs, __VA_ARGS__ }) : NULL)
548
549#define fb(width, name) \
550        xf(width, name, current->name, 0, MAX_UINT_BITS(width), 0, )
551#define fc(width, name, range_min, range_max) \
552        xf(width, name, current->name, range_min, range_max, 0, )
553#define flag(name) fb(1, name)
554#define su(width, name) \
555        xsu(width, name, current->name, 0, )
556
557#define fbs(width, name, subs, ...) \
558        xf(width, name, current->name, 0, MAX_UINT_BITS(width), subs, __VA_ARGS__)
559#define fcs(width, name, range_min, range_max, subs, ...) \
560        xf(width, name, current->name, range_min, range_max, subs, __VA_ARGS__)
561#define flags(name, subs, ...) \
562        xf(1, name, current->name, 0, 1, subs, __VA_ARGS__)
563#define sus(width, name, subs, ...) \
564        xsu(width, name, current->name, subs, __VA_ARGS__)
565
566#define fixed(width, name, value) do { \
567        av_unused uint32_t fixed_value = value; \
568        xf(width, name, fixed_value, value, value, 0, ); \
569    } while (0)
570
571
572#define READ
573#define READWRITE read
574#define RWContext GetBitContext
575
576#define xf(width, name, var, range_min, range_max, subs, ...) do { \
577        uint32_t value; \
578        CHECK(ff_cbs_read_unsigned(ctx, rw, width, #name, \
579                                   SUBSCRIPTS(subs, __VA_ARGS__), \
580                                   &value, range_min, range_max)); \
581        var = value; \
582    } while (0)
583
584#define xsu(width, name, var, subs, ...) do { \
585        int32_t value; \
586        CHECK(ff_cbs_read_signed(ctx, rw, width, #name, \
587                                 SUBSCRIPTS(subs, __VA_ARGS__), &value, \
588                                 MIN_INT_BITS(width), \
589                                 MAX_INT_BITS(width))); \
590        var = value; \
591    } while (0)
592
593#define uvlc(name, range_min, range_max) do { \
594        uint32_t value; \
595        CHECK(cbs_av1_read_uvlc(ctx, rw, #name, \
596                                &value, range_min, range_max)); \
597        current->name = value; \
598    } while (0)
599
600#define ns(max_value, name, subs, ...) do { \
601        uint32_t value; \
602        CHECK(cbs_av1_read_ns(ctx, rw, max_value, #name, \
603                              SUBSCRIPTS(subs, __VA_ARGS__), &value)); \
604        current->name = value; \
605    } while (0)
606
607#define increment(name, min, max) do { \
608        uint32_t value; \
609        CHECK(cbs_av1_read_increment(ctx, rw, min, max, #name, &value)); \
610        current->name = value; \
611    } while (0)
612
613#define subexp(name, max, subs, ...) do { \
614        uint32_t value; \
615        CHECK(cbs_av1_read_subexp(ctx, rw, max, #name, \
616                                  SUBSCRIPTS(subs, __VA_ARGS__), &value)); \
617        current->name = value; \
618    } while (0)
619
620#define delta_q(name) do { \
621        uint8_t delta_coded; \
622        int8_t delta_q; \
623        xf(1, name.delta_coded, delta_coded, 0, 1, 0, ); \
624        if (delta_coded) \
625            xsu(1 + 6, name.delta_q, delta_q, 0, ); \
626        else \
627            delta_q = 0; \
628        current->name = delta_q; \
629    } while (0)
630
631#define leb128(name) do { \
632        uint64_t value; \
633        CHECK(cbs_av1_read_leb128(ctx, rw, #name, &value)); \
634        current->name = value; \
635    } while (0)
636
637#define infer(name, value) do { \
638        current->name = value; \
639    } while (0)
640
641#define byte_alignment(rw) (get_bits_count(rw) % 8)
642
643#include "cbs_av1_syntax_template.c"
644
645#undef READ
646#undef READWRITE
647#undef RWContext
648#undef xf
649#undef xsu
650#undef uvlc
651#undef ns
652#undef increment
653#undef subexp
654#undef delta_q
655#undef leb128
656#undef infer
657#undef byte_alignment
658
659
660#define WRITE
661#define READWRITE write
662#define RWContext PutBitContext
663
664#define xf(width, name, var, range_min, range_max, subs, ...) do { \
665        CHECK(ff_cbs_write_unsigned(ctx, rw, width, #name, \
666                                    SUBSCRIPTS(subs, __VA_ARGS__), \
667                                    var, range_min, range_max)); \
668    } while (0)
669
670#define xsu(width, name, var, subs, ...) do { \
671        CHECK(ff_cbs_write_signed(ctx, rw, width, #name, \
672                                  SUBSCRIPTS(subs, __VA_ARGS__), var, \
673                                  MIN_INT_BITS(width), \
674                                  MAX_INT_BITS(width))); \
675    } while (0)
676
677#define uvlc(name, range_min, range_max) do { \
678        CHECK(cbs_av1_write_uvlc(ctx, rw, #name, current->name, \
679                                 range_min, range_max)); \
680    } while (0)
681
682#define ns(max_value, name, subs, ...) do { \
683        CHECK(cbs_av1_write_ns(ctx, rw, max_value, #name, \
684                               SUBSCRIPTS(subs, __VA_ARGS__), \
685                               current->name)); \
686    } while (0)
687
688#define increment(name, min, max) do { \
689        CHECK(cbs_av1_write_increment(ctx, rw, min, max, #name, \
690                                      current->name)); \
691    } while (0)
692
693#define subexp(name, max, subs, ...) do { \
694        CHECK(cbs_av1_write_subexp(ctx, rw, max, #name, \
695                                   SUBSCRIPTS(subs, __VA_ARGS__), \
696                                   current->name)); \
697    } while (0)
698
699#define delta_q(name) do { \
700        xf(1, name.delta_coded, current->name != 0, 0, 1, 0, ); \
701        if (current->name) \
702            xsu(1 + 6, name.delta_q, current->name, 0, ); \
703    } while (0)
704
705#define leb128(name) do { \
706        CHECK(cbs_av1_write_leb128(ctx, rw, #name, current->name)); \
707    } while (0)
708
709#define infer(name, value) do { \
710        if (current->name != (value)) { \
711            av_log(ctx->log_ctx, AV_LOG_ERROR, \
712                   "%s does not match inferred value: " \
713                   "%"PRId64", but should be %"PRId64".\n", \
714                   #name, (int64_t)current->name, (int64_t)(value)); \
715            return AVERROR_INVALIDDATA; \
716        } \
717    } while (0)
718
719#define byte_alignment(rw) (put_bits_count(rw) % 8)
720
721#include "cbs_av1_syntax_template.c"
722
723#undef WRITE
724#undef READWRITE
725#undef RWContext
726#undef xf
727#undef xsu
728#undef uvlc
729#undef ns
730#undef increment
731#undef subexp
732#undef delta_q
733#undef leb128
734#undef infer
735#undef byte_alignment
736
737
738static int cbs_av1_split_fragment(CodedBitstreamContext *ctx,
739                                  CodedBitstreamFragment *frag,
740                                  int header)
741{
742    GetBitContext gbc;
743    uint8_t *data;
744    size_t size;
745    uint64_t obu_length;
746    int pos, err, trace;
747
748    // Don't include this parsing in trace output.
749    trace = ctx->trace_enable;
750    ctx->trace_enable = 0;
751
752    data = frag->data;
753    size = frag->data_size;
754
755    if (INT_MAX / 8 < size) {
756        av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid fragment: "
757               "too large (%"SIZE_SPECIFIER" bytes).\n", size);
758        err = AVERROR_INVALIDDATA;
759        goto fail;
760    }
761
762    if (header && size && data[0] & 0x80) {
763        // first bit is nonzero, the extradata does not consist purely of
764        // OBUs. Expect MP4/Matroska AV1CodecConfigurationRecord
765        int config_record_version = data[0] & 0x7f;
766
767        if (config_record_version != 1) {
768            av_log(ctx->log_ctx, AV_LOG_ERROR,
769                   "Unknown version %d of AV1CodecConfigurationRecord "
770                   "found!\n",
771                   config_record_version);
772            err = AVERROR_INVALIDDATA;
773            goto fail;
774        }
775
776        if (size <= 4) {
777            if (size < 4) {
778                av_log(ctx->log_ctx, AV_LOG_WARNING,
779                       "Undersized AV1CodecConfigurationRecord v%d found!\n",
780                       config_record_version);
781                err = AVERROR_INVALIDDATA;
782                goto fail;
783            }
784
785            goto success;
786        }
787
788        // In AV1CodecConfigurationRecord v1, actual OBUs start after
789        // four bytes. Thus set the offset as required for properly
790        // parsing them.
791        data += 4;
792        size -= 4;
793    }
794
795    while (size > 0) {
796        AV1RawOBUHeader header;
797        uint64_t obu_size;
798
799        init_get_bits(&gbc, data, 8 * size);
800
801        err = cbs_av1_read_obu_header(ctx, &gbc, &header);
802        if (err < 0)
803            goto fail;
804
805        if (header.obu_has_size_field) {
806            if (get_bits_left(&gbc) < 8) {
807                av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid OBU: fragment "
808                       "too short (%"SIZE_SPECIFIER" bytes).\n", size);
809                err = AVERROR_INVALIDDATA;
810                goto fail;
811            }
812            err = cbs_av1_read_leb128(ctx, &gbc, "obu_size", &obu_size);
813            if (err < 0)
814                goto fail;
815        } else
816            obu_size = size - 1 - header.obu_extension_flag;
817
818        pos = get_bits_count(&gbc);
819        av_assert0(pos % 8 == 0 && pos / 8 <= size);
820
821        obu_length = pos / 8 + obu_size;
822
823        if (size < obu_length) {
824            av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid OBU length: "
825                   "%"PRIu64", but only %"SIZE_SPECIFIER" bytes remaining in fragment.\n",
826                   obu_length, size);
827            err = AVERROR_INVALIDDATA;
828            goto fail;
829        }
830
831        err = ff_cbs_append_unit_data(frag, header.obu_type,
832                                      data, obu_length, frag->data_ref);
833        if (err < 0)
834            goto fail;
835
836        data += obu_length;
837        size -= obu_length;
838    }
839
840success:
841    err = 0;
842fail:
843    ctx->trace_enable = trace;
844    return err;
845}
846
847static int cbs_av1_ref_tile_data(CodedBitstreamContext *ctx,
848                                 CodedBitstreamUnit *unit,
849                                 GetBitContext *gbc,
850                                 AV1RawTileData *td)
851{
852    int pos;
853
854    pos = get_bits_count(gbc);
855    if (pos >= 8 * unit->data_size) {
856        av_log(ctx->log_ctx, AV_LOG_ERROR, "Bitstream ended before "
857               "any data in tile group (%d bits read).\n", pos);
858        return AVERROR_INVALIDDATA;
859    }
860    // Must be byte-aligned at this point.
861    av_assert0(pos % 8 == 0);
862
863    td->data_ref = av_buffer_ref(unit->data_ref);
864    if (!td->data_ref)
865        return AVERROR(ENOMEM);
866
867    td->data      = unit->data      + pos / 8;
868    td->data_size = unit->data_size - pos / 8;
869
870    return 0;
871}
872
873static int cbs_av1_read_unit(CodedBitstreamContext *ctx,
874                             CodedBitstreamUnit *unit)
875{
876    CodedBitstreamAV1Context *priv = ctx->priv_data;
877    AV1RawOBU *obu;
878    GetBitContext gbc;
879    int err, start_pos, end_pos;
880
881    err = ff_cbs_alloc_unit_content2(ctx, unit);
882    if (err < 0)
883        return err;
884    obu = unit->content;
885
886    err = init_get_bits(&gbc, unit->data, 8 * unit->data_size);
887    if (err < 0)
888        return err;
889
890    err = cbs_av1_read_obu_header(ctx, &gbc, &obu->header);
891    if (err < 0)
892        return err;
893    av_assert0(obu->header.obu_type == unit->type);
894
895    if (obu->header.obu_has_size_field) {
896        uint64_t obu_size;
897        err = cbs_av1_read_leb128(ctx, &gbc, "obu_size", &obu_size);
898        if (err < 0)
899            return err;
900        obu->obu_size = obu_size;
901    } else {
902        if (unit->data_size < 1 + obu->header.obu_extension_flag) {
903            av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid OBU length: "
904                   "unit too short (%"SIZE_SPECIFIER").\n", unit->data_size);
905            return AVERROR_INVALIDDATA;
906        }
907        obu->obu_size = unit->data_size - 1 - obu->header.obu_extension_flag;
908    }
909
910    start_pos = get_bits_count(&gbc);
911
912    if (obu->header.obu_extension_flag) {
913        if (obu->header.obu_type != AV1_OBU_SEQUENCE_HEADER &&
914            obu->header.obu_type != AV1_OBU_TEMPORAL_DELIMITER &&
915            priv->operating_point_idc) {
916            int in_temporal_layer =
917                (priv->operating_point_idc >>  priv->temporal_id    ) & 1;
918            int in_spatial_layer  =
919                (priv->operating_point_idc >> (priv->spatial_id + 8)) & 1;
920            if (!in_temporal_layer || !in_spatial_layer) {
921                return AVERROR(EAGAIN); // drop_obu()
922            }
923        }
924    }
925
926    switch (obu->header.obu_type) {
927    case AV1_OBU_SEQUENCE_HEADER:
928        {
929            err = cbs_av1_read_sequence_header_obu(ctx, &gbc,
930                                                   &obu->obu.sequence_header);
931            if (err < 0)
932                return err;
933
934            if (priv->operating_point >= 0) {
935                AV1RawSequenceHeader *sequence_header = &obu->obu.sequence_header;
936
937                if (priv->operating_point > sequence_header->operating_points_cnt_minus_1) {
938                    av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid Operating Point %d requested. "
939                                                       "Must not be higher than %u.\n",
940                           priv->operating_point, sequence_header->operating_points_cnt_minus_1);
941                    return AVERROR(EINVAL);
942                }
943                priv->operating_point_idc = sequence_header->operating_point_idc[priv->operating_point];
944            }
945
946            av_buffer_unref(&priv->sequence_header_ref);
947            priv->sequence_header = NULL;
948
949            priv->sequence_header_ref = av_buffer_ref(unit->content_ref);
950            if (!priv->sequence_header_ref)
951                return AVERROR(ENOMEM);
952            priv->sequence_header = &obu->obu.sequence_header;
953        }
954        break;
955    case AV1_OBU_TEMPORAL_DELIMITER:
956        {
957            err = cbs_av1_read_temporal_delimiter_obu(ctx, &gbc);
958            if (err < 0)
959                return err;
960        }
961        break;
962    case AV1_OBU_FRAME_HEADER:
963    case AV1_OBU_REDUNDANT_FRAME_HEADER:
964        {
965            err = cbs_av1_read_frame_header_obu(ctx, &gbc,
966                                                &obu->obu.frame_header,
967                                                obu->header.obu_type ==
968                                                AV1_OBU_REDUNDANT_FRAME_HEADER,
969                                                unit->data_ref);
970            if (err < 0)
971                return err;
972        }
973        break;
974    case AV1_OBU_TILE_GROUP:
975        {
976            err = cbs_av1_read_tile_group_obu(ctx, &gbc,
977                                              &obu->obu.tile_group);
978            if (err < 0)
979                return err;
980
981            err = cbs_av1_ref_tile_data(ctx, unit, &gbc,
982                                        &obu->obu.tile_group.tile_data);
983            if (err < 0)
984                return err;
985        }
986        break;
987    case AV1_OBU_FRAME:
988        {
989            err = cbs_av1_read_frame_obu(ctx, &gbc, &obu->obu.frame,
990                                         unit->data_ref);
991            if (err < 0)
992                return err;
993
994            err = cbs_av1_ref_tile_data(ctx, unit, &gbc,
995                                        &obu->obu.frame.tile_group.tile_data);
996            if (err < 0)
997                return err;
998        }
999        break;
1000    case AV1_OBU_TILE_LIST:
1001        {
1002            err = cbs_av1_read_tile_list_obu(ctx, &gbc,
1003                                             &obu->obu.tile_list);
1004            if (err < 0)
1005                return err;
1006
1007            err = cbs_av1_ref_tile_data(ctx, unit, &gbc,
1008                                        &obu->obu.tile_list.tile_data);
1009            if (err < 0)
1010                return err;
1011        }
1012        break;
1013    case AV1_OBU_METADATA:
1014        {
1015            err = cbs_av1_read_metadata_obu(ctx, &gbc, &obu->obu.metadata);
1016            if (err < 0)
1017                return err;
1018        }
1019        break;
1020    case AV1_OBU_PADDING:
1021        {
1022            err = cbs_av1_read_padding_obu(ctx, &gbc, &obu->obu.padding);
1023            if (err < 0)
1024                return err;
1025        }
1026        break;
1027    default:
1028        return AVERROR(ENOSYS);
1029    }
1030
1031    end_pos = get_bits_count(&gbc);
1032    av_assert0(end_pos <= unit->data_size * 8);
1033
1034    if (obu->obu_size > 0 &&
1035        obu->header.obu_type != AV1_OBU_TILE_GROUP &&
1036        obu->header.obu_type != AV1_OBU_TILE_LIST &&
1037        obu->header.obu_type != AV1_OBU_FRAME) {
1038        int nb_bits = obu->obu_size * 8 + start_pos - end_pos;
1039
1040        if (nb_bits <= 0)
1041            return AVERROR_INVALIDDATA;
1042
1043        err = cbs_av1_read_trailing_bits(ctx, &gbc, nb_bits);
1044        if (err < 0)
1045            return err;
1046    }
1047
1048    return 0;
1049}
1050
1051static int cbs_av1_write_obu(CodedBitstreamContext *ctx,
1052                             CodedBitstreamUnit *unit,
1053                             PutBitContext *pbc)
1054{
1055    CodedBitstreamAV1Context *priv = ctx->priv_data;
1056    AV1RawOBU *obu = unit->content;
1057    PutBitContext pbc_tmp;
1058    AV1RawTileData *td;
1059    size_t header_size;
1060    int err, start_pos, end_pos, data_pos;
1061
1062    // OBUs in the normal bitstream format must contain a size field
1063    // in every OBU (in annex B it is optional, but we don't support
1064    // writing that).
1065    obu->header.obu_has_size_field = 1;
1066
1067    err = cbs_av1_write_obu_header(ctx, pbc, &obu->header);
1068    if (err < 0)
1069        return err;
1070
1071    if (obu->header.obu_has_size_field) {
1072        pbc_tmp = *pbc;
1073        // Add space for the size field to fill later.
1074        put_bits32(pbc, 0);
1075        put_bits32(pbc, 0);
1076    }
1077
1078    td = NULL;
1079    start_pos = put_bits_count(pbc);
1080
1081    switch (obu->header.obu_type) {
1082    case AV1_OBU_SEQUENCE_HEADER:
1083        {
1084            err = cbs_av1_write_sequence_header_obu(ctx, pbc,
1085                                                    &obu->obu.sequence_header);
1086            if (err < 0)
1087                return err;
1088
1089            av_buffer_unref(&priv->sequence_header_ref);
1090            priv->sequence_header = NULL;
1091
1092            err = ff_cbs_make_unit_refcounted(ctx, unit);
1093            if (err < 0)
1094                return err;
1095
1096            priv->sequence_header_ref = av_buffer_ref(unit->content_ref);
1097            if (!priv->sequence_header_ref)
1098                return AVERROR(ENOMEM);
1099            priv->sequence_header = &obu->obu.sequence_header;
1100        }
1101        break;
1102    case AV1_OBU_TEMPORAL_DELIMITER:
1103        {
1104            err = cbs_av1_write_temporal_delimiter_obu(ctx, pbc);
1105            if (err < 0)
1106                return err;
1107        }
1108        break;
1109    case AV1_OBU_FRAME_HEADER:
1110    case AV1_OBU_REDUNDANT_FRAME_HEADER:
1111        {
1112            err = cbs_av1_write_frame_header_obu(ctx, pbc,
1113                                                 &obu->obu.frame_header,
1114                                                 obu->header.obu_type ==
1115                                                 AV1_OBU_REDUNDANT_FRAME_HEADER,
1116                                                 NULL);
1117            if (err < 0)
1118                return err;
1119        }
1120        break;
1121    case AV1_OBU_TILE_GROUP:
1122        {
1123            err = cbs_av1_write_tile_group_obu(ctx, pbc,
1124                                               &obu->obu.tile_group);
1125            if (err < 0)
1126                return err;
1127
1128            td = &obu->obu.tile_group.tile_data;
1129        }
1130        break;
1131    case AV1_OBU_FRAME:
1132        {
1133            err = cbs_av1_write_frame_obu(ctx, pbc, &obu->obu.frame, NULL);
1134            if (err < 0)
1135                return err;
1136
1137            td = &obu->obu.frame.tile_group.tile_data;
1138        }
1139        break;
1140    case AV1_OBU_TILE_LIST:
1141        {
1142            err = cbs_av1_write_tile_list_obu(ctx, pbc, &obu->obu.tile_list);
1143            if (err < 0)
1144                return err;
1145
1146            td = &obu->obu.tile_list.tile_data;
1147        }
1148        break;
1149    case AV1_OBU_METADATA:
1150        {
1151            err = cbs_av1_write_metadata_obu(ctx, pbc, &obu->obu.metadata);
1152            if (err < 0)
1153                return err;
1154        }
1155        break;
1156    case AV1_OBU_PADDING:
1157        {
1158            err = cbs_av1_write_padding_obu(ctx, pbc, &obu->obu.padding);
1159            if (err < 0)
1160                return err;
1161        }
1162        break;
1163    default:
1164        return AVERROR(ENOSYS);
1165    }
1166
1167    end_pos = put_bits_count(pbc);
1168    header_size = (end_pos - start_pos + 7) / 8;
1169    if (td) {
1170        obu->obu_size = header_size + td->data_size;
1171    } else if (header_size > 0) {
1172        // Add trailing bits and recalculate.
1173        err = cbs_av1_write_trailing_bits(ctx, pbc, 8 - end_pos % 8);
1174        if (err < 0)
1175            return err;
1176        end_pos = put_bits_count(pbc);
1177        obu->obu_size = header_size = (end_pos - start_pos + 7) / 8;
1178    } else {
1179        // Empty OBU.
1180        obu->obu_size = 0;
1181    }
1182
1183    end_pos = put_bits_count(pbc);
1184    // Must now be byte-aligned.
1185    av_assert0(end_pos % 8 == 0);
1186    flush_put_bits(pbc);
1187    start_pos /= 8;
1188    end_pos   /= 8;
1189
1190    *pbc = pbc_tmp;
1191    err = cbs_av1_write_leb128(ctx, pbc, "obu_size", obu->obu_size);
1192    if (err < 0)
1193        return err;
1194
1195    data_pos = put_bits_count(pbc) / 8;
1196    flush_put_bits(pbc);
1197    av_assert0(data_pos <= start_pos);
1198
1199    if (8 * obu->obu_size > put_bits_left(pbc))
1200        return AVERROR(ENOSPC);
1201
1202    if (obu->obu_size > 0) {
1203        memmove(pbc->buf + data_pos,
1204                pbc->buf + start_pos, header_size);
1205        skip_put_bytes(pbc, header_size);
1206
1207        if (td) {
1208            memcpy(pbc->buf + data_pos + header_size,
1209                   td->data, td->data_size);
1210            skip_put_bytes(pbc, td->data_size);
1211        }
1212    }
1213
1214    // OBU data must be byte-aligned.
1215    av_assert0(put_bits_count(pbc) % 8 == 0);
1216
1217    return 0;
1218}
1219
1220static int cbs_av1_assemble_fragment(CodedBitstreamContext *ctx,
1221                                     CodedBitstreamFragment *frag)
1222{
1223    size_t size, pos;
1224    int i;
1225
1226    size = 0;
1227    for (i = 0; i < frag->nb_units; i++)
1228        size += frag->units[i].data_size;
1229
1230    frag->data_ref = av_buffer_alloc(size + AV_INPUT_BUFFER_PADDING_SIZE);
1231    if (!frag->data_ref)
1232        return AVERROR(ENOMEM);
1233    frag->data = frag->data_ref->data;
1234    memset(frag->data + size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
1235
1236    pos = 0;
1237    for (i = 0; i < frag->nb_units; i++) {
1238        memcpy(frag->data + pos, frag->units[i].data,
1239               frag->units[i].data_size);
1240        pos += frag->units[i].data_size;
1241    }
1242    av_assert0(pos == size);
1243    frag->data_size = size;
1244
1245    return 0;
1246}
1247
1248static void cbs_av1_flush(CodedBitstreamContext *ctx)
1249{
1250    CodedBitstreamAV1Context *priv = ctx->priv_data;
1251
1252    av_buffer_unref(&priv->frame_header_ref);
1253    priv->sequence_header = NULL;
1254    priv->frame_header = NULL;
1255
1256    memset(priv->ref, 0, sizeof(priv->ref));
1257    priv->operating_point_idc = 0;
1258    priv->seen_frame_header = 0;
1259    priv->tile_num = 0;
1260}
1261
1262static void cbs_av1_close(CodedBitstreamContext *ctx)
1263{
1264    CodedBitstreamAV1Context *priv = ctx->priv_data;
1265
1266    av_buffer_unref(&priv->sequence_header_ref);
1267    av_buffer_unref(&priv->frame_header_ref);
1268}
1269
1270static void cbs_av1_free_metadata(void *unit, uint8_t *content)
1271{
1272    AV1RawOBU *obu = (AV1RawOBU*)content;
1273    AV1RawMetadata *md;
1274
1275    av_assert0(obu->header.obu_type == AV1_OBU_METADATA);
1276    md = &obu->obu.metadata;
1277
1278    switch (md->metadata_type) {
1279    case AV1_METADATA_TYPE_ITUT_T35:
1280        av_buffer_unref(&md->metadata.itut_t35.payload_ref);
1281        break;
1282    }
1283    av_free(content);
1284}
1285
1286static const CodedBitstreamUnitTypeDescriptor cbs_av1_unit_types[] = {
1287    CBS_UNIT_TYPE_POD(AV1_OBU_SEQUENCE_HEADER,        AV1RawOBU),
1288    CBS_UNIT_TYPE_POD(AV1_OBU_TEMPORAL_DELIMITER,     AV1RawOBU),
1289    CBS_UNIT_TYPE_POD(AV1_OBU_FRAME_HEADER,           AV1RawOBU),
1290    CBS_UNIT_TYPE_POD(AV1_OBU_REDUNDANT_FRAME_HEADER, AV1RawOBU),
1291
1292    CBS_UNIT_TYPE_INTERNAL_REF(AV1_OBU_TILE_GROUP, AV1RawOBU,
1293                               obu.tile_group.tile_data.data),
1294    CBS_UNIT_TYPE_INTERNAL_REF(AV1_OBU_FRAME,      AV1RawOBU,
1295                               obu.frame.tile_group.tile_data.data),
1296    CBS_UNIT_TYPE_INTERNAL_REF(AV1_OBU_TILE_LIST,  AV1RawOBU,
1297                               obu.tile_list.tile_data.data),
1298    CBS_UNIT_TYPE_INTERNAL_REF(AV1_OBU_PADDING,    AV1RawOBU,
1299                               obu.padding.payload),
1300
1301    CBS_UNIT_TYPE_COMPLEX(AV1_OBU_METADATA, AV1RawOBU,
1302                          &cbs_av1_free_metadata),
1303
1304    CBS_UNIT_TYPE_END_OF_LIST
1305};
1306
1307#define OFFSET(x) offsetof(CodedBitstreamAV1Context, x)
1308static const AVOption cbs_av1_options[] = {
1309    { "operating_point",  "Set operating point to select layers to parse from a scalable bitstream",
1310                          OFFSET(operating_point), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, AV1_MAX_OPERATING_POINTS - 1, 0 },
1311    { NULL }
1312};
1313
1314static const AVClass cbs_av1_class = {
1315    .class_name = "cbs_av1",
1316    .item_name  = av_default_item_name,
1317    .option     = cbs_av1_options,
1318    .version    = LIBAVUTIL_VERSION_INT,
1319};
1320
1321const CodedBitstreamType ff_cbs_type_av1 = {
1322    .codec_id          = AV_CODEC_ID_AV1,
1323
1324    .priv_class        = &cbs_av1_class,
1325    .priv_data_size    = sizeof(CodedBitstreamAV1Context),
1326
1327    .unit_types        = cbs_av1_unit_types,
1328
1329    .split_fragment    = &cbs_av1_split_fragment,
1330    .read_unit         = &cbs_av1_read_unit,
1331    .write_unit        = &cbs_av1_write_obu,
1332    .assemble_fragment = &cbs_av1_assemble_fragment,
1333
1334    .flush             = &cbs_av1_flush,
1335    .close             = &cbs_av1_close,
1336};
1337