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 "bytestream.h"
20#include "h2645_parse.h"
21#include "hevc.h"
22#include "hevc_parse.h"
23
24static int hevc_decode_nal_units(const uint8_t *buf, int buf_size, HEVCParamSets *ps,
25                                 HEVCSEI *sei, int is_nalff, int nal_length_size,
26                                 int err_recognition, int apply_defdispwin, void *logctx)
27{
28    int i;
29    int ret = 0;
30    H2645Packet pkt = { 0 };
31
32    ret = ff_h2645_packet_split(&pkt, buf, buf_size, logctx, is_nalff,
33                                nal_length_size, AV_CODEC_ID_HEVC, 1, 0);
34    if (ret < 0) {
35        goto done;
36    }
37
38    for (i = 0; i < pkt.nb_nals; i++) {
39        H2645NAL *nal = &pkt.nals[i];
40        if (nal->nuh_layer_id > 0)
41            continue;
42
43        /* ignore everything except parameter sets and VCL NALUs */
44        switch (nal->type) {
45        case HEVC_NAL_VPS:
46            ret = ff_hevc_decode_nal_vps(&nal->gb, logctx, ps);
47            if (ret < 0)
48                goto done;
49            break;
50        case HEVC_NAL_SPS:
51            ret = ff_hevc_decode_nal_sps(&nal->gb, logctx, ps, apply_defdispwin);
52            if (ret < 0)
53                goto done;
54            break;
55        case HEVC_NAL_PPS:
56            ret = ff_hevc_decode_nal_pps(&nal->gb, logctx, ps);
57            if (ret < 0)
58                goto done;
59            break;
60        case HEVC_NAL_SEI_PREFIX:
61        case HEVC_NAL_SEI_SUFFIX:
62            ret = ff_hevc_decode_nal_sei(&nal->gb, logctx, sei, ps, nal->type);
63            if (ret < 0)
64                goto done;
65            break;
66        default:
67            av_log(logctx, AV_LOG_VERBOSE, "Ignoring NAL type %d in extradata\n", nal->type);
68            break;
69        }
70    }
71
72done:
73    ff_h2645_packet_uninit(&pkt);
74    if (err_recognition & AV_EF_EXPLODE)
75        return ret;
76
77    return 0;
78}
79
80int ff_hevc_decode_extradata(const uint8_t *data, int size, HEVCParamSets *ps,
81                             HEVCSEI *sei, int *is_nalff, int *nal_length_size,
82                             int err_recognition, int apply_defdispwin, void *logctx)
83{
84    int ret = 0;
85    GetByteContext gb;
86
87    bytestream2_init(&gb, data, size);
88
89    if (size > 3 && (data[0] || data[1] || data[2] > 1)) {
90        /* It seems the extradata is encoded as hvcC format.
91         * Temporarily, we support configurationVersion==0 until 14496-15 3rd
92         * is finalized. When finalized, configurationVersion will be 1 and we
93         * can recognize hvcC by checking if avctx->extradata[0]==1 or not. */
94        int i, j, num_arrays, nal_len_size;
95
96        *is_nalff = 1;
97
98        bytestream2_skip(&gb, 21);
99        nal_len_size = (bytestream2_get_byte(&gb) & 3) + 1;
100        num_arrays   = bytestream2_get_byte(&gb);
101
102        /* nal units in the hvcC always have length coded with 2 bytes,
103         * so put a fake nal_length_size = 2 while parsing them */
104        *nal_length_size = 2;
105
106        /* Decode nal units from hvcC. */
107        for (i = 0; i < num_arrays; i++) {
108            int type = bytestream2_get_byte(&gb) & 0x3f;
109            int cnt  = bytestream2_get_be16(&gb);
110
111            for (j = 0; j < cnt; j++) {
112                // +2 for the nal size field
113                int nalsize = bytestream2_peek_be16(&gb) + 2;
114                if (bytestream2_get_bytes_left(&gb) < nalsize) {
115                    av_log(logctx, AV_LOG_ERROR,
116                           "Invalid NAL unit size in extradata.\n");
117                    return AVERROR_INVALIDDATA;
118                }
119
120                ret = hevc_decode_nal_units(gb.buffer, nalsize, ps, sei, *is_nalff,
121                                            *nal_length_size, err_recognition, apply_defdispwin,
122                                            logctx);
123                if (ret < 0) {
124                    av_log(logctx, AV_LOG_ERROR,
125                           "Decoding nal unit %d %d from hvcC failed\n",
126                           type, i);
127                    return ret;
128                }
129                bytestream2_skip(&gb, nalsize);
130            }
131        }
132
133        /* Now store right nal length size, that will be used to parse
134         * all other nals */
135        *nal_length_size = nal_len_size;
136    } else {
137        *is_nalff = 0;
138        ret = hevc_decode_nal_units(data, size, ps, sei, *is_nalff, *nal_length_size,
139                                    err_recognition, apply_defdispwin, logctx);
140        if (ret < 0)
141            return ret;
142    }
143
144    return ret;
145}
146