summaryrefslogtreecommitdiff
path: root/libavformat/av1.c
blob: b6eaf506278e4353c739682d87b6f4a2c5372657 (plain)
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
/*
 * AV1 helper functions for muxers
 * Copyright (c) 2018 James Almer <jamrial@gmail.com>
 *
 * 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/avassert.h"
#include "libavutil/mem.h"
#include "libavcodec/av1.h"
#include "libavcodec/av1_parse.h"
#include "libavcodec/avcodec.h"
#include "libavcodec/put_bits.h"
#include "av1.h"
#include "avio.h"
#include "avio_internal.h"

static int av1_filter_obus(AVIOContext *pb, const uint8_t *buf,
                           int size, int *offset)
{
    const uint8_t *start = buf, *end = buf + size;
    int off;
    enum {
        START_NOT_FOUND,
        START_FOUND,
        END_FOUND,
        OFFSET_IMPOSSIBLE,
    } state = START_NOT_FOUND;

    off = size = 0;
    while (buf < end) {
        int64_t obu_size;
        int start_pos, type, temporal_id, spatial_id;
        int len = parse_obu_header(buf, end - buf, &obu_size, &start_pos,
                                   &type, &temporal_id, &spatial_id);
        if (len < 0)
            return len;

        switch (type) {
        case AV1_OBU_TEMPORAL_DELIMITER:
        case AV1_OBU_REDUNDANT_FRAME_HEADER:
        case AV1_OBU_TILE_LIST:
        case AV1_OBU_PADDING:
            if (state == START_FOUND)
                state = END_FOUND;
            break;
        default:
            if (state == START_NOT_FOUND) {
                off   = buf - start;
                state = START_FOUND;
            } else if (state == END_FOUND) {
                state = OFFSET_IMPOSSIBLE;
            }
            if (pb)
                avio_write(pb, buf, len);
            size += len;
            break;
        }
        buf += len;
    }

    if (offset)
        *offset = state != OFFSET_IMPOSSIBLE ? off : -1;

    return size;
}

int ff_av1_filter_obus(AVIOContext *pb, const uint8_t *buf, int size)
{
    return av1_filter_obus(pb, buf, size, NULL);
}

int ff_av1_filter_obus_buf(const uint8_t *in, uint8_t **out,
                           int *size, int *offset)
{
    FFIOContext pb;
    uint8_t *buf;
    int len, off, ret;

    len = ret = av1_filter_obus(NULL, in, *size, &off);
    if (ret < 0) {
        return ret;
    }
    if (off >= 0) {
        *out    = (uint8_t *)in;
        *size   = len;
        *offset = off;

        return 0;
    }

    buf = av_malloc(len + AV_INPUT_BUFFER_PADDING_SIZE);
    if (!buf)
        return AVERROR(ENOMEM);

    ffio_init_context(&pb, buf, len, 1, NULL, NULL, NULL, NULL);

    ret = av1_filter_obus(&pb.pub, in, *size, NULL);
    av_assert1(ret == len);

    memset(buf + len, 0, AV_INPUT_BUFFER_PADDING_SIZE);

    *out  = buf;
    *size = len;
    *offset = 0;

    return 0;
}

static inline void uvlc(GetBitContext *gb)
{
    int leading_zeros = 0;

    while (get_bits_left(gb)) {
        if (get_bits1(gb))
            break;
        leading_zeros++;
    }

    if (leading_zeros >= 32)
        return;

    skip_bits_long(gb, leading_zeros);
}

static int parse_color_config(AV1SequenceParameters *seq_params, GetBitContext *gb)
{
    int twelve_bit = 0;
    int high_bitdepth = get_bits1(gb);
    if (seq_params->profile == FF_PROFILE_AV1_PROFESSIONAL && high_bitdepth)
        twelve_bit = get_bits1(gb);

    seq_params->bitdepth = 8 + (high_bitdepth * 2) + (twelve_bit * 2);

    if (seq_params->profile == FF_PROFILE_AV1_HIGH)
        seq_params->monochrome = 0;
    else
        seq_params->monochrome = get_bits1(gb);

    seq_params->color_description_present_flag = get_bits1(gb);
    if (seq_params->color_description_present_flag) {
        seq_params->color_primaries          = get_bits(gb, 8);
        seq_params->transfer_characteristics = get_bits(gb, 8);
        seq_params->matrix_coefficients      = get_bits(gb, 8);
    } else {
        seq_params->color_primaries          = AVCOL_PRI_UNSPECIFIED;
        seq_params->transfer_characteristics = AVCOL_TRC_UNSPECIFIED;
        seq_params->matrix_coefficients      = AVCOL_SPC_UNSPECIFIED;
    }

    if (seq_params->monochrome) {
        seq_params->color_range = get_bits1(gb);
        seq_params->chroma_subsampling_x = 1;
        seq_params->chroma_subsampling_y = 1;
        seq_params->chroma_sample_position = 0;
        return 0;
    } else if (seq_params->color_primaries          == AVCOL_PRI_BT709 &&
               seq_params->transfer_characteristics == AVCOL_TRC_IEC61966_2_1 &&
               seq_params->matrix_coefficients      == AVCOL_SPC_RGB) {
        seq_params->chroma_subsampling_x = 0;
        seq_params->chroma_subsampling_y = 0;
    } else {
        seq_params->color_range = get_bits1(gb);

        if (seq_params->profile == FF_PROFILE_AV1_MAIN) {
            seq_params->chroma_subsampling_x = 1;
            seq_params->chroma_subsampling_y = 1;
        } else if (seq_params->profile == FF_PROFILE_AV1_HIGH) {
            seq_params->chroma_subsampling_x = 0;
            seq_params->chroma_subsampling_y = 0;
        } else {
            if (twelve_bit) {
                seq_params->chroma_subsampling_x = get_bits1(gb);
                if (seq_params->chroma_subsampling_x)
                    seq_params->chroma_subsampling_y = get_bits1(gb);
                else
                    seq_params->chroma_subsampling_y = 0;
            } else {
                seq_params->chroma_subsampling_x = 1;
                seq_params->chroma_subsampling_y = 0;
            }
        }
        if (seq_params->chroma_subsampling_x && seq_params->chroma_subsampling_y)
            seq_params->chroma_sample_position = get_bits(gb, 2);
    }

    skip_bits1(gb); // separate_uv_delta_q

    return 0;
}

static int parse_sequence_header(AV1SequenceParameters *seq_params, const uint8_t *buf, int size)
{
    GetBitContext gb;
    int reduced_still_picture_header;
    int frame_width_bits_minus_1, frame_height_bits_minus_1;
    int size_bits, ret;

    size_bits = get_obu_bit_length(buf, size, AV1_OBU_SEQUENCE_HEADER);
    if (size_bits < 0)
        return size_bits;

    ret = init_get_bits(&gb, buf, size_bits);
    if (ret < 0)
        return ret;

    memset(seq_params, 0, sizeof(*seq_params));

    seq_params->profile = get_bits(&gb, 3);

    skip_bits1(&gb); // still_picture
    reduced_still_picture_header = get_bits1(&gb);

    if (reduced_still_picture_header) {
        seq_params->level = get_bits(&gb, 5);
        seq_params->tier = 0;
    } else {
        int initial_display_delay_present_flag, operating_points_cnt_minus_1;
        int decoder_model_info_present_flag, buffer_delay_length_minus_1;

        if (get_bits1(&gb)) { // timing_info_present_flag
            skip_bits_long(&gb, 32); // num_units_in_display_tick
            skip_bits_long(&gb, 32); // time_scale

            if (get_bits1(&gb)) // equal_picture_interval
                uvlc(&gb); // num_ticks_per_picture_minus_1

            decoder_model_info_present_flag = get_bits1(&gb);
            if (decoder_model_info_present_flag) {
                buffer_delay_length_minus_1 = get_bits(&gb, 5);
                skip_bits_long(&gb, 32); // num_units_in_decoding_tick
                skip_bits(&gb, 10); // buffer_removal_time_length_minus_1 (5)
                                    // frame_presentation_time_length_minus_1 (5)
            }
        } else
            decoder_model_info_present_flag = 0;

        initial_display_delay_present_flag = get_bits1(&gb);

        operating_points_cnt_minus_1 = get_bits(&gb, 5);
        for (int i = 0; i <= operating_points_cnt_minus_1; i++) {
            int seq_level_idx, seq_tier;

            skip_bits(&gb, 12); // operating_point_idc
            seq_level_idx = get_bits(&gb, 5);

            if (seq_level_idx > 7)
                seq_tier = get_bits1(&gb);
            else
                seq_tier = 0;

            if (decoder_model_info_present_flag) {
                if (get_bits1(&gb)) { // decoder_model_present_for_this_op
                    skip_bits_long(&gb, buffer_delay_length_minus_1 + 1); // decoder_buffer_delay
                    skip_bits_long(&gb, buffer_delay_length_minus_1 + 1); // encoder_buffer_delay
                    skip_bits1(&gb); // low_delay_mode_flag
                }
            }

            if (initial_display_delay_present_flag) {
                if (get_bits1(&gb)) // initial_display_delay_present_for_this_op
                    skip_bits(&gb, 4); // initial_display_delay_minus_1
            }

            if (i == 0) {
               seq_params->level = seq_level_idx;
               seq_params->tier = seq_tier;
            }
        }
    }

    frame_width_bits_minus_1  = get_bits(&gb, 4);
    frame_height_bits_minus_1 = get_bits(&gb, 4);

    skip_bits(&gb, frame_width_bits_minus_1 + 1); // max_frame_width_minus_1
    skip_bits(&gb, frame_height_bits_minus_1 + 1); // max_frame_height_minus_1

    if (!reduced_still_picture_header) {
        if (get_bits1(&gb)) // frame_id_numbers_present_flag
            skip_bits(&gb, 7); // delta_frame_id_length_minus_2 (4), additional_frame_id_length_minus_1 (3)
    }

    skip_bits(&gb, 3); // use_128x128_superblock (1), enable_filter_intra (1), enable_intra_edge_filter (1)

    if (!reduced_still_picture_header) {
        int enable_order_hint, seq_force_screen_content_tools;

        skip_bits(&gb, 4); // enable_interintra_compound (1), enable_masked_compound (1)
                           // enable_warped_motion (1), enable_dual_filter (1)

        enable_order_hint = get_bits1(&gb);
        if (enable_order_hint)
            skip_bits(&gb, 2); // enable_jnt_comp (1), enable_ref_frame_mvs (1)

        if (get_bits1(&gb)) // seq_choose_screen_content_tools
            seq_force_screen_content_tools = 2;
        else
            seq_force_screen_content_tools = get_bits1(&gb);

        if (seq_force_screen_content_tools) {
            if (!get_bits1(&gb)) // seq_choose_integer_mv
                skip_bits1(&gb); // seq_force_integer_mv
        }

        if (enable_order_hint)
            skip_bits(&gb, 3); // order_hint_bits_minus_1
    }

    skip_bits(&gb, 3); // enable_superres (1), enable_cdef (1), enable_restoration (1)

    parse_color_config(seq_params, &gb);

    skip_bits1(&gb); // film_grain_params_present

    if (get_bits_left(&gb))
        return AVERROR_INVALIDDATA;

    return 0;
}

int ff_av1_parse_seq_header(AV1SequenceParameters *seq, const uint8_t *buf, int size)
{
    int is_av1c;

    if (size <= 0)
        return AVERROR_INVALIDDATA;

    is_av1c = !!(buf[0] & 0x80);
    if (is_av1c) {
        GetBitContext gb;
        int ret, version = buf[0] & 0x7F;

        if (version != 1 || size < 4)
            return AVERROR_INVALIDDATA;

        ret = init_get_bits8(&gb, buf, 4);
        if (ret < 0)
            return ret;

        memset(seq, 0, sizeof(*seq));

        skip_bits(&gb, 8);
        seq->profile    = get_bits(&gb, 3);
        seq->level      = get_bits(&gb, 5);
        seq->tier       = get_bits(&gb, 1);
        seq->bitdepth   = get_bits(&gb, 1) * 2 + 8;
        seq->bitdepth  += get_bits(&gb, 1) * 2;
        seq->monochrome               = get_bits(&gb, 1);
        seq->chroma_subsampling_x     = get_bits(&gb, 1);
        seq->chroma_subsampling_y     = get_bits(&gb, 1);
        seq->chroma_sample_position   = get_bits(&gb, 2);
        seq->color_primaries          = AVCOL_PRI_UNSPECIFIED;
        seq->transfer_characteristics = AVCOL_TRC_UNSPECIFIED;
        seq->matrix_coefficients      = AVCOL_SPC_UNSPECIFIED;

        size -= 4;
        buf  += 4;
    }

    while (size > 0) {
        int64_t obu_size;
        int start_pos, type, temporal_id, spatial_id;
        int len = parse_obu_header(buf, size, &obu_size, &start_pos,
                                   &type, &temporal_id, &spatial_id);
        if (len < 0)
            return len;

        switch (type) {
        case AV1_OBU_SEQUENCE_HEADER:
            if (!obu_size)
                return AVERROR_INVALIDDATA;

            return parse_sequence_header(seq, buf + start_pos, obu_size);
        default:
            break;
        }
        size -= len;
        buf  += len;
    }

    return is_av1c ? 0 : AVERROR_INVALIDDATA;
}

int ff_isom_write_av1c(AVIOContext *pb, const uint8_t *buf, int size,
                       int write_seq_header)
{
    AVIOContext *meta_pb;
    AV1SequenceParameters seq_params;
    PutBitContext pbc;
    uint8_t header[4], *meta;
    const uint8_t *seq;
    int ret, nb_seq = 0, seq_size, meta_size;

    if (size <= 0)
        return AVERROR_INVALIDDATA;

    if (buf[0] & 0x80) {
        // first bit is nonzero, the passed data does not consist purely of
        // OBUs. Expect that the data is already in AV1CodecConfigurationRecord
        // format.
        int config_record_version = buf[0] & 0x7f;
        if (config_record_version != 1 || size < 4) {
            return AVERROR_INVALIDDATA;
        }

        avio_write(pb, buf, size);

        return 0;
    }

    ret = avio_open_dyn_buf(&meta_pb);
    if (ret < 0)
        return ret;

    while (size > 0) {
        int64_t obu_size;
        int start_pos, type, temporal_id, spatial_id;
        int len = parse_obu_header(buf, size, &obu_size, &start_pos,
                                   &type, &temporal_id, &spatial_id);
        if (len < 0) {
            ret = len;
            goto fail;
        }

        switch (type) {
        case AV1_OBU_SEQUENCE_HEADER:
            nb_seq++;
            if (!obu_size || nb_seq > 1) {
                ret = AVERROR_INVALIDDATA;
                goto fail;
            }
            ret = parse_sequence_header(&seq_params, buf + start_pos, obu_size);
            if (ret < 0)
                goto fail;

            seq      = buf;
            seq_size = len;
            break;
        case AV1_OBU_METADATA:
            if (!obu_size) {
                ret = AVERROR_INVALIDDATA;
                goto fail;
            }
            avio_write(meta_pb, buf, len);
            break;
        default:
            break;
        }
        size -= len;
        buf  += len;
    }

    if (!nb_seq) {
        ret = AVERROR_INVALIDDATA;
        goto fail;
    }

    init_put_bits(&pbc, header, sizeof(header));

    put_bits(&pbc, 1, 1); // marker
    put_bits(&pbc, 7, 1); // version
    put_bits(&pbc, 3, seq_params.profile);
    put_bits(&pbc, 5, seq_params.level);
    put_bits(&pbc, 1, seq_params.tier);
    put_bits(&pbc, 1, seq_params.bitdepth > 8);
    put_bits(&pbc, 1, seq_params.bitdepth == 12);
    put_bits(&pbc, 1, seq_params.monochrome);
    put_bits(&pbc, 1, seq_params.chroma_subsampling_x);
    put_bits(&pbc, 1, seq_params.chroma_subsampling_y);
    put_bits(&pbc, 2, seq_params.chroma_sample_position);
    put_bits(&pbc, 8, 0); // padding
    flush_put_bits(&pbc);

    avio_write(pb, header, sizeof(header));
    if (write_seq_header) {
        avio_write(pb, seq, seq_size);
    }

    meta_size = avio_get_dyn_buf(meta_pb, &meta);
    if (meta_size)
        avio_write(pb, meta, meta_size);

fail:
    ffio_free_dyn_buf(&meta_pb);

    return ret;
}