xref: /third_party/ffmpeg/libavcodec/dsddec.c (revision cabdff1a) 
1/*
2 * Direct Stream Digital (DSD) decoder
3 * based on BSD licensed dsd2pcm by Sebastian Gesemann
4 * Copyright (c) 2009, 2011 Sebastian Gesemann. All rights reserved.
5 * Copyright (c) 2014 Peter Ross
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24/**
25 * @file
26 * Direct Stream Digital (DSD) decoder
27 */
28
29#include "libavcodec/internal.h"
30#include "avcodec.h"
31#include "codec_internal.h"
32#include "dsd.h"
33
34#define DSD_SILENCE 0x69
35#define DSD_SILENCE_REVERSED 0x96
36/* 0x69 = 01101001
37 * This pattern "on repeat" makes a low energy 352.8 kHz tone
38 * and a high energy 1.0584 MHz tone which should be filtered
39 * out completely by any playback system --> silence
40 */
41
42static av_cold int decode_init(AVCodecContext *avctx)
43{
44    DSDContext * s;
45    int i;
46    uint8_t silence;
47
48    if (!avctx->ch_layout.nb_channels)
49        return AVERROR_INVALIDDATA;
50
51    ff_init_dsd_data();
52
53    s = av_malloc_array(sizeof(DSDContext), avctx->ch_layout.nb_channels);
54    if (!s)
55        return AVERROR(ENOMEM);
56
57    silence = avctx->codec_id == AV_CODEC_ID_DSD_LSBF || avctx->codec_id == AV_CODEC_ID_DSD_LSBF_PLANAR ? DSD_SILENCE_REVERSED : DSD_SILENCE;
58    for (i = 0; i < avctx->ch_layout.nb_channels; i++) {
59        s[i].pos = 0;
60        memset(s[i].buf, silence, sizeof(s[i].buf));
61    }
62
63    avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
64    avctx->priv_data  = s;
65    return 0;
66}
67
68typedef struct ThreadData {
69    AVFrame *frame;
70    const AVPacket *avpkt;
71} ThreadData;
72
73static int dsd_channel(AVCodecContext *avctx, void *tdata, int j, int threadnr)
74{
75    int lsbf = avctx->codec_id == AV_CODEC_ID_DSD_LSBF || avctx->codec_id == AV_CODEC_ID_DSD_LSBF_PLANAR;
76    DSDContext *s = avctx->priv_data;
77    ThreadData *td = tdata;
78    AVFrame *frame = td->frame;
79    const AVPacket *avpkt = td->avpkt;
80    int src_next, src_stride;
81    float *dst = ((float **)frame->extended_data)[j];
82
83    if (avctx->codec_id == AV_CODEC_ID_DSD_LSBF_PLANAR || avctx->codec_id == AV_CODEC_ID_DSD_MSBF_PLANAR) {
84        src_next   = frame->nb_samples;
85        src_stride = 1;
86    } else {
87        src_next   = 1;
88        src_stride = avctx->ch_layout.nb_channels;
89    }
90
91    ff_dsd2pcm_translate(&s[j], frame->nb_samples, lsbf,
92                         avpkt->data + j * src_next, src_stride,
93                         dst, 1);
94
95    return 0;
96}
97
98static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
99                        int *got_frame_ptr, AVPacket *avpkt)
100{
101    ThreadData td;
102    int ret;
103
104    frame->nb_samples = avpkt->size / avctx->ch_layout.nb_channels;
105
106    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
107        return ret;
108
109    td.frame = frame;
110    td.avpkt = avpkt;
111    avctx->execute2(avctx, dsd_channel, &td, NULL, avctx->ch_layout.nb_channels);
112
113    *got_frame_ptr = 1;
114    return frame->nb_samples * avctx->ch_layout.nb_channels;
115}
116
117#define DSD_DECODER(id_, name_, long_name_) \
118const FFCodec ff_ ## name_ ## _decoder = { \
119    .p.name       = #name_, \
120    .p.long_name  = NULL_IF_CONFIG_SMALL(long_name_), \
121    .p.type       = AVMEDIA_TYPE_AUDIO, \
122    .p.id         = AV_CODEC_ID_##id_, \
123    .init         = decode_init, \
124    FF_CODEC_DECODE_CB(decode_frame), \
125    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_SLICE_THREADS, \
126    .p.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP, \
127                                                   AV_SAMPLE_FMT_NONE }, \
128    .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, \
129};
130
131DSD_DECODER(DSD_LSBF, dsd_lsbf, "DSD (Direct Stream Digital), least significant bit first")
132DSD_DECODER(DSD_MSBF, dsd_msbf, "DSD (Direct Stream Digital), most significant bit first")
133DSD_DECODER(DSD_MSBF_PLANAR, dsd_msbf_planar, "DSD (Direct Stream Digital), most significant bit first, planar")
134DSD_DECODER(DSD_LSBF_PLANAR, dsd_lsbf_planar, "DSD (Direct Stream Digital), least significant bit first, planar")
135