FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/dvaudiodec.c
Date: 2021-09-22 05:58:22
Exec Total Coverage
Lines: 0 53 0.0%
Branches: 0 32 0.0%

Line Branch Exec Source
1 /*
2 * Copyright (c) 2012 Laurent Aimar
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 "libavutil/channel_layout.h"
22 #include "libavutil/intreadwrite.h"
23 #include "avcodec.h"
24 #include "internal.h"
25 #include "dvaudio.h"
26
27 typedef struct DVAudioContext {
28 int block_size;
29 int is_12bit;
30 int is_pal;
31 int16_t shuffle[2000];
32 } DVAudioContext;
33
34 static av_cold int decode_init(AVCodecContext *avctx)
35 {
36 DVAudioContext *s = avctx->priv_data;
37 int i;
38
39 if (avctx->channels != 2) {
40 av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
41 return AVERROR(EINVAL);
42 }
43
44 if (avctx->codec_tag == 0x0215) {
45 s->block_size = 7200;
46 } else if (avctx->codec_tag == 0x0216) {
47 s->block_size = 8640;
48 } else if (avctx->block_align == 7200 ||
49 avctx->block_align == 8640) {
50 s->block_size = avctx->block_align;
51 } else {
52 return AVERROR(EINVAL);
53 }
54
55 s->is_pal = s->block_size == 8640;
56 s->is_12bit = avctx->bits_per_coded_sample == 12;
57 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
58 avctx->channel_layout = AV_CH_LAYOUT_STEREO;
59
60 for (i = 0; i < FF_ARRAY_ELEMS(s->shuffle); i++) {
61 const unsigned a = s->is_pal ? 18 : 15;
62 const unsigned b = 3 * a;
63
64 s->shuffle[i] = 80 * ((21 * (i % 3) + 9 * (i / 3) + ((i / a) % 3)) % b) +
65 (2 + s->is_12bit) * (i / b) + 8;
66 }
67
68 return 0;
69 }
70
71 static inline uint16_t dv_audio_12to16(uint16_t sample)
72 {
73 uint16_t shift, result;
74
75 sample = (sample < 0x800) ? sample : sample | 0xf000;
76 shift = (sample & 0xf00) >> 8;
77
78 if (shift < 0x2 || shift > 0xd) {
79 result = sample;
80 } else if (shift < 0x8) {
81 shift--;
82 result = (sample - (256 * shift)) << shift;
83 } else {
84 shift = 0xe - shift;
85 result = ((sample + ((256 * shift) + 1)) << shift) - 1;
86 }
87
88 return result;
89 }
90
91 static int decode_frame(AVCodecContext *avctx, void *data,
92 int *got_frame_ptr, AVPacket *pkt)
93 {
94 DVAudioContext *s = avctx->priv_data;
95 AVFrame *frame = data;
96 const uint8_t *src = pkt->data;
97 int16_t *dst;
98 int ret, i;
99
100 if (pkt->size < s->block_size)
101 return AVERROR_INVALIDDATA;
102
103 frame->nb_samples = dv_get_audio_sample_count(pkt->data + 244, s->is_pal);
104 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
105 return ret;
106 dst = (int16_t *)frame->data[0];
107
108 for (i = 0; i < frame->nb_samples; i++) {
109 const uint8_t *v = &src[s->shuffle[i]];
110
111 if (s->is_12bit) {
112 *dst++ = dv_audio_12to16((v[0] << 4) | ((v[2] >> 4) & 0x0f));
113 *dst++ = dv_audio_12to16((v[1] << 4) | ((v[2] >> 0) & 0x0f));
114 } else {
115 *dst++ = AV_RB16(&v[0]);
116 *dst++ = AV_RB16(&v[s->is_pal ? 4320 : 3600]);
117 }
118 }
119
120 *got_frame_ptr = 1;
121
122 return s->block_size;
123 }
124
125 const AVCodec ff_dvaudio_decoder = {
126 .name = "dvaudio",
127 .long_name = NULL_IF_CONFIG_SMALL("Ulead DV Audio"),
128 .type = AVMEDIA_TYPE_AUDIO,
129 .id = AV_CODEC_ID_DVAUDIO,
130 .init = decode_init,
131 .decode = decode_frame,
132 .capabilities = AV_CODEC_CAP_DR1,
133 .priv_data_size = sizeof(DVAudioContext),
134 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
135 };
136