| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * Copyright (c) 2026 Zhao Zhili | ||
| 3 | * | ||
| 4 | * This file is part of FFmpeg. | ||
| 5 | * | ||
| 6 | * FFmpeg is free software; you can redistribute it and/or | ||
| 7 | * modify it under the terms of the GNU Lesser General Public | ||
| 8 | * License as published by the Free Software Foundation; either | ||
| 9 | * version 2.1 of the License, or (at your option) any later version. | ||
| 10 | * | ||
| 11 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 14 | * Lesser General Public License for more details. | ||
| 15 | * | ||
| 16 | * You should have received a copy of the GNU Lesser General Public | ||
| 17 | * License along with FFmpeg; if not, write to the Free Software | ||
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 19 | */ | ||
| 20 | |||
| 21 | #include <limits.h> | ||
| 22 | |||
| 23 | #include "libavutil/intreadwrite.h" | ||
| 24 | #include "libavutil/mem.h" | ||
| 25 | #include "avformat.h" | ||
| 26 | #include "demux.h" | ||
| 27 | #include "internal.h" | ||
| 28 | |||
| 29 | /* | ||
| 30 | * Layout: [512 B header][index: N x 8 B (start_ms:u32, offset:u32)] | ||
| 31 | * [chunks: 16 B local header + H.264 Annex-B NALs] | ||
| 32 | * Each chunk is a self-contained GOP (SPS+PPS+IDR + P-slices). | ||
| 33 | */ | ||
| 34 | #define MVR_HEADER_SIZE 512 | ||
| 35 | #define MVR_ENTRY_SIZE 8 | ||
| 36 | #define MVR_CHUNK_HEADER 16 | ||
| 37 | |||
| 38 | typedef struct MVRContext { | ||
| 39 | /* index of the chunk to read next */ | ||
| 40 | unsigned next_chunk; | ||
| 41 | } MVRContext; | ||
| 42 | |||
| 43 | 8071 | static int mvr_probe(const AVProbeData *p) | |
| 44 | { | ||
| 45 | unsigned width, height; | ||
| 46 | unsigned index_table_size, index_capacity, index_count; | ||
| 47 | size_t index_size; | ||
| 48 | |||
| 49 |
2/2✓ Branch 0 taken 5 times.
✓ Branch 1 taken 8066 times.
|
8071 | if (p->buf_size < 0x40) |
| 50 | 5 | return 0; | |
| 51 | |||
| 52 |
1/2✓ Branch 0 taken 8066 times.
✗ Branch 1 not taken.
|
8066 | if (AV_RL32(p->buf) != 4) |
| 53 | 8066 | return 0; | |
| 54 | |||
| 55 | ✗ | width = AV_RL32(p->buf + 0x04); | |
| 56 | ✗ | height = AV_RL32(p->buf + 0x08); | |
| 57 | ✗ | if (width == 0 || width > 8192 || height == 0 || height > 8192) | |
| 58 | ✗ | return 0; | |
| 59 | |||
| 60 | ✗ | index_table_size = AV_RL32(p->buf + 0x34); | |
| 61 | ✗ | index_capacity = AV_RL32(p->buf + 0x38); | |
| 62 | ✗ | index_count = AV_RL32(p->buf + 0x3c); | |
| 63 | |||
| 64 | ✗ | if (index_capacity == 0 || | |
| 65 | ✗ | av_size_mult(index_capacity, MVR_ENTRY_SIZE, &index_size) < 0 || | |
| 66 | ✗ | index_table_size != index_size || | |
| 67 | index_count > index_capacity) | ||
| 68 | ✗ | return 0; | |
| 69 | |||
| 70 | /* Must outrank h264 */ | ||
| 71 | ✗ | return AVPROBE_SCORE_EXTENSION + 2; | |
| 72 | } | ||
| 73 | |||
| 74 | ✗ | static int mvr_read_header(AVFormatContext *s) | |
| 75 | { | ||
| 76 | ✗ | AVIOContext *pb = s->pb; | |
| 77 | AVStream *st; | ||
| 78 | int64_t filesize; | ||
| 79 | uint64_t time_meta_ms; | ||
| 80 | uint32_t index_count, start_ms, offset; | ||
| 81 | int64_t index_table_size, data_start; | ||
| 82 | int ret; | ||
| 83 | |||
| 84 | ✗ | filesize = avio_size(pb); | |
| 85 | ✗ | if (filesize < MVR_HEADER_SIZE + MVR_ENTRY_SIZE) | |
| 86 | ✗ | return AVERROR_INVALIDDATA; | |
| 87 | |||
| 88 | ✗ | st = avformat_new_stream(s, NULL); | |
| 89 | ✗ | if (!st) | |
| 90 | ✗ | return AVERROR(ENOMEM); | |
| 91 | |||
| 92 | ✗ | st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; | |
| 93 | ✗ | st->codecpar->codec_id = AV_CODEC_ID_H264; | |
| 94 | ✗ | ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL; | |
| 95 | ✗ | avpriv_set_pts_info(st, 64, 1, 1000); | |
| 96 | |||
| 97 | ✗ | avio_skip(pb, 4); | |
| 98 | ✗ | st->codecpar->width = avio_rl32(pb); | |
| 99 | ✗ | st->codecpar->height = avio_rl32(pb); | |
| 100 | |||
| 101 | ✗ | avio_skip(pb, 0x28 - 0x0c); | |
| 102 | ✗ | time_meta_ms = avio_rl64(pb); | |
| 103 | ✗ | ff_dict_set_timestamp(&s->metadata, "creation_time", | |
| 104 | ✗ | time_meta_ms * 1000); | |
| 105 | ✗ | st->duration = avio_rl32(pb); | |
| 106 | |||
| 107 | /* Skip index_capacity; data starts after the full index table. */ | ||
| 108 | ✗ | index_table_size = avio_rl32(pb); | |
| 109 | ✗ | avio_skip(pb, 4); | |
| 110 | ✗ | index_count = avio_rl32(pb); | |
| 111 | |||
| 112 | ✗ | if (index_table_size == 0 || | |
| 113 | ✗ | index_table_size > UINT32_MAX - MVR_HEADER_SIZE || | |
| 114 | ✗ | index_table_size % MVR_ENTRY_SIZE != 0 || | |
| 115 | ✗ | index_table_size / MVR_ENTRY_SIZE < index_count) | |
| 116 | ✗ | return AVERROR_INVALIDDATA; | |
| 117 | |||
| 118 | ✗ | if (avio_seek(pb, MVR_HEADER_SIZE, SEEK_SET) < 0) | |
| 119 | ✗ | return AVERROR_INVALIDDATA; | |
| 120 | |||
| 121 | ✗ | data_start = MVR_HEADER_SIZE + index_table_size; | |
| 122 | ✗ | if (filesize < data_start) | |
| 123 | ✗ | return AVERROR_INVALIDDATA; | |
| 124 | |||
| 125 | ✗ | start_ms = avio_rl32(pb); | |
| 126 | ✗ | offset = avio_rl32(pb); | |
| 127 | ✗ | for (unsigned i = 0; i < index_count; i++) { | |
| 128 | uint32_t next_start_ms; | ||
| 129 | int64_t next_offset, chunk_size; | ||
| 130 | |||
| 131 | ✗ | if (i + 1 < index_count) { | |
| 132 | ✗ | next_start_ms = avio_rl32(pb); | |
| 133 | ✗ | next_offset = avio_rl32(pb); | |
| 134 | } else { | ||
| 135 | ✗ | next_start_ms = 0; | |
| 136 | ✗ | next_offset = filesize; | |
| 137 | } | ||
| 138 | |||
| 139 | ✗ | if (offset < data_start || next_offset > filesize) | |
| 140 | ✗ | return AVERROR_INVALIDDATA; | |
| 141 | |||
| 142 | ✗ | chunk_size = next_offset - offset; | |
| 143 | ✗ | if (chunk_size <= MVR_CHUNK_HEADER || chunk_size > INT_MAX) | |
| 144 | ✗ | return AVERROR_INVALIDDATA; | |
| 145 | |||
| 146 | ✗ | ret = av_add_index_entry(st, offset, start_ms, | |
| 147 | chunk_size, 0, AVINDEX_KEYFRAME); | ||
| 148 | ✗ | if (ret < 0) | |
| 149 | ✗ | return ret; | |
| 150 | |||
| 151 | ✗ | start_ms = next_start_ms; | |
| 152 | ✗ | offset = next_offset; | |
| 153 | } | ||
| 154 | |||
| 155 | ✗ | return 0; | |
| 156 | } | ||
| 157 | |||
| 158 | ✗ | static int mvr_read_packet(AVFormatContext *s, AVPacket *pkt) | |
| 159 | { | ||
| 160 | ✗ | MVRContext *mvr = s->priv_data; | |
| 161 | ✗ | AVStream *st = s->streams[0]; | |
| 162 | ✗ | FFStream *const sti = ffstream(st); | |
| 163 | AVIndexEntry *e; | ||
| 164 | int64_t h264_pos; | ||
| 165 | int h264_size, ret; | ||
| 166 | |||
| 167 | /* Resync after a generic seek. */ | ||
| 168 | ✗ | if (s->io_repositioned) { | |
| 169 | ✗ | int idx = av_index_search_timestamp(st, sti->cur_dts, | |
| 170 | AVSEEK_FLAG_BACKWARD); | ||
| 171 | ✗ | if (idx < 0) | |
| 172 | ✗ | return AVERROR(EINVAL); | |
| 173 | ✗ | mvr->next_chunk = idx; | |
| 174 | ✗ | s->io_repositioned = 0; | |
| 175 | } | ||
| 176 | |||
| 177 | ✗ | if (mvr->next_chunk >= sti->nb_index_entries) | |
| 178 | ✗ | return AVERROR_EOF; | |
| 179 | |||
| 180 | ✗ | e = &sti->index_entries[mvr->next_chunk]; | |
| 181 | ✗ | h264_pos = e->pos + MVR_CHUNK_HEADER; | |
| 182 | ✗ | h264_size = e->size - MVR_CHUNK_HEADER; | |
| 183 | |||
| 184 | ✗ | if (avio_seek(s->pb, h264_pos, SEEK_SET) < 0) | |
| 185 | ✗ | return AVERROR_EOF; | |
| 186 | |||
| 187 | ✗ | ret = av_get_packet(s->pb, pkt, h264_size); | |
| 188 | ✗ | if (ret < 0) | |
| 189 | ✗ | return ret; | |
| 190 | |||
| 191 | ✗ | pkt->pts = e->timestamp; | |
| 192 | ✗ | pkt->dts = AV_NOPTS_VALUE; | |
| 193 | ✗ | pkt->pos = e->pos; | |
| 194 | ✗ | mvr->next_chunk++; | |
| 195 | |||
| 196 | ✗ | return 0; | |
| 197 | } | ||
| 198 | |||
| 199 | const FFInputFormat ff_mvr_demuxer = { | ||
| 200 | .p.name = "mvr", | ||
| 201 | .p.long_name = NULL_IF_CONFIG_SMALL("MVR CCTV"), | ||
| 202 | .p.extensions = "mvr", | ||
| 203 | .p.flags = AVFMT_GENERIC_INDEX, | ||
| 204 | .priv_data_size = sizeof(MVRContext), | ||
| 205 | .read_probe = mvr_probe, | ||
| 206 | .read_header = mvr_read_header, | ||
| 207 | .read_packet = mvr_read_packet, | ||
| 208 | }; | ||
| 209 |