FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavformat/dtsdec.c
Date: 2025-11-01 17:46:10
Exec Total Coverage
Lines: 56 66 84.8%
Functions: 1 1 100.0%
Branches: 41 62 66.1%
Line Branch Exec Source
1 /*
2 * RAW DTS demuxer
3 * Copyright (c) 2008 Benjamin Larsson
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "libavutil/crc.h"
23
24 #include "libavcodec/bytestream.h"
25 #include "libavcodec/dca.h"
26 #include "libavcodec/dca_syncwords.h"
27 #include "libavcodec/get_bits.h"
28
29 #include "avformat.h"
30 #include "demux.h"
31 #include "rawdec.h"
32
33 7282 static int dts_probe(const AVProbeData *p)
34 {
35 const uint8_t *buf, *bufp;
36 7282 uint32_t state = -1;
37 7282 int markers[4*16] = {0};
38 7282 int exss_markers = 0, exss_nextpos = 0;
39 int sum, max, pos, ret, i;
40 7282 int64_t diff = 0;
41 7282 int diffcount = 1;
42 7282 uint8_t hdr[DCA_CORE_FRAME_HEADER_SIZE + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 };
43
44
2/2
✓ Branch 0 taken 185351665 times.
✓ Branch 1 taken 7282 times.
 185358947 for (pos = FFMIN(4096, p->buf_size); pos < p->buf_size - 2; pos += 2) {
45 int marker, wide_hdr, hdr_size, framesize;
46 DCACoreFrameHeader h;
47 GetBitContext gb;
48
49 185351665 bufp = buf = p->buf + pos;
50 185351665 state = (state << 16) | bytestream_get_be16(&bufp);
51
52
1/2
✓ Branch 0 taken 185351665 times.
✗ Branch 1 not taken.
 185351665 if (pos >= 4) {
53
4/4
✓ Branch 0 taken 4072368 times.
✓ Branch 1 taken 181279297 times.
✓ Branch 2 taken 803776 times.
✓ Branch 3 taken 3268592 times.
 185351665 if (AV_RL16(buf) || AV_RL16(buf-4)) {
54
2/2
✓ Branch 0 taken 106880681 times.
✓ Branch 1 taken 75202392 times.
 182083073 diff += FFABS(((int16_t)AV_RL16(buf)) - (int16_t)AV_RL16(buf-4));
55 182083073 diffcount ++;
56 }
57 }
58
59 /* extension substream (EXSS) */
60
2/2
✓ Branch 0 taken 28 times.
✓ Branch 1 taken 185351637 times.
 185351665 if (state == DCA_SYNCWORD_SUBSTREAM) {
61
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 28 times.
 28 if (pos < exss_nextpos)
62 185351601 continue;
63
64 28 init_get_bits(&gb, buf - 2, 96);
65 28 skip_bits_long(&gb, 42);
66
67 28 wide_hdr = get_bits1(&gb);
68 28 hdr_size = get_bits(&gb, 8 + 4 * wide_hdr) + 1;
69 28 framesize = get_bits(&gb, 16 + 4 * wide_hdr) + 1;
70
2/4
✓ Branch 0 taken 28 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 28 times.
 28 if (hdr_size & 3 || framesize & 3)
71 ✗ continue;
72
2/4
✓ Branch 0 taken 28 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 28 times.
 28 if (hdr_size < 16 || framesize < hdr_size)
73 ✗ continue;
74
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 28 times.
 28 if (pos - 2 + hdr_size > p->buf_size)
75 ✗ continue;
76
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 28 times.
 28 if (av_crc(av_crc_get_table(AV_CRC_16_CCITT), 0xffff, buf + 3, hdr_size - 5))
77 ✗ continue;
78
79
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 28 times.
 28 if (pos == exss_nextpos)
80 ✗ exss_markers++;
81 else
82 28 exss_markers = FFMAX(1, exss_markers - 1);
83 28 exss_nextpos = pos + framesize;
84 28 continue;
85 }
86
87 /* regular bitstream */
88
2/2
✓ Branch 0 taken 50 times.
✓ Branch 1 taken 185351587 times.
 185351637 if (state == DCA_SYNCWORD_CORE_BE &&
89
1/2
✓ Branch 1 taken 50 times.
✗ Branch 2 not taken.
 50 (bytestream_get_be16(&bufp) & 0xFC00) == 0xFC00)
90 50 marker = 0;
91
2/2
✓ Branch 0 taken 4 times.
✓ Branch 1 taken 185351583 times.
 185351587 else if (state == DCA_SYNCWORD_CORE_LE &&
92
1/2
✓ Branch 1 taken 4 times.
✗ Branch 2 not taken.
 4 (bytestream_get_be16(&bufp) & 0x00FC) == 0x00FC)
93 4 marker = 1;
94
95 /* 14 bits big-endian bitstream */
96
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 185351583 times.
 185351583 else if (state == DCA_SYNCWORD_CORE_14B_BE &&
97 ✗ (bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
98 ✗ marker = 2;
99
100 /* 14 bits little-endian bitstream */
101
2/2
✓ Branch 0 taken 10 times.
✓ Branch 1 taken 185351573 times.
 185351583 else if (state == DCA_SYNCWORD_CORE_14B_LE &&
102
1/2
✓ Branch 1 taken 10 times.
✗ Branch 2 not taken.
 10 (bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
103 10 marker = 3;
104 else
105 185351573 continue;
106
107
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 64 times.
 64 if ((ret = avpriv_dca_convert_bitstream(buf - 2, DCA_CORE_FRAME_HEADER_SIZE,
108 hdr, DCA_CORE_FRAME_HEADER_SIZE)) < 0)
109 ✗ continue;
110
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 64 times.
 64 if (avpriv_dca_parse_core_frame_header(&h, hdr, ret) < 0)
111 ✗ continue;
112
113 64 marker += 4 * h.sr_code;
114
115 64 markers[marker] ++;
116 }
117
118
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 7282 times.
 7282 if (exss_markers > 3)
119 ✗ return AVPROBE_SCORE_EXTENSION + 1;
120
121 7282 sum = max = 0;
122
2/2
✓ Branch 0 taken 466048 times.
✓ Branch 1 taken 7282 times.
 473330 for (i=0; i<FF_ARRAY_ELEMS(markers); i++) {
123 466048 sum += markers[i];
124
2/2
✓ Branch 0 taken 18 times.
✓ Branch 1 taken 466030 times.
 466048 if (markers[max] < markers[i])
125 18 max = i;
126 }
127
128
3/4
✓ Branch 0 taken 8 times.
✓ Branch 1 taken 7274 times.
✓ Branch 2 taken 8 times.
✗ Branch 3 not taken.
 7282 if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 &&
129
1/2
✓ Branch 0 taken 8 times.
✗ Branch 1 not taken.
 8 markers[max] * 4 > sum * 3 &&
130
1/2
✓ Branch 0 taken 8 times.
✗ Branch 1 not taken.
 8 diff / diffcount > 600)
131 8 return AVPROBE_SCORE_EXTENSION + 1;
132
133 7274 return 0;
134 }
135
136 const FFInputFormat ff_dts_demuxer = {
137 .p.name = "dts",
138 .p.long_name = NULL_IF_CONFIG_SMALL("raw DTS"),
139 .p.flags = AVFMT_GENERIC_INDEX,
140 .p.extensions = "dts",
141 .p.priv_class = &ff_raw_demuxer_class,
142 .read_probe = dts_probe,
143 .read_header = ff_raw_audio_read_header,
144 .read_packet = ff_raw_read_partial_packet,
145 .raw_codec_id = AV_CODEC_ID_DTS,
146 .priv_data_size = sizeof(FFRawDemuxerContext),
147 };
148