FFmpeg
qoadec.c
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1 /*
2  * QOA decoder
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 "avcodec.h"
22 #include "codec_internal.h"
23 #include "decode.h"
24 #include "get_bits.h"
25 #include "bytestream.h"
26 #include "mathops.h"
27 
28 #define QOA_SLICE_LEN 20
29 #define QOA_LMS_LEN 4
30 
31 typedef struct QOAChannel {
34 } QOAChannel;
35 
36 typedef struct QOAContext {
37  QOAChannel ch[256];
38 } QOAContext;
39 
40 static const int16_t qoa_dequant_tab[16][8] = {
41  { 1, -1, 3, -3, 5, -5, 7, -7},
42  { 5, -5, 18, -18, 32, -32, 49, -49},
43  { 16, -16, 53, -53, 95, -95, 147, -147},
44  { 34, -34, 113, -113, 203, -203, 315, -315},
45  { 63, -63, 210, -210, 378, -378, 588, -588},
46  { 104, -104, 345, -345, 621, -621, 966, -966},
47  { 158, -158, 528, -528, 950, -950, 1477, -1477},
48  { 228, -228, 760, -760, 1368, -1368, 2128, -2128},
49  { 316, -316, 1053, -1053, 1895, -1895, 2947, -2947},
50  { 422, -422, 1405, -1405, 2529, -2529, 3934, -3934},
51  { 548, -548, 1828, -1828, 3290, -3290, 5117, -5117},
52  { 696, -696, 2320, -2320, 4176, -4176, 6496, -6496},
53  { 868, -868, 2893, -2893, 5207, -5207, 8099, -8099},
54  {1064, -1064, 3548, -3548, 6386, -6386, 9933, -9933},
55  {1286, -1286, 4288, -4288, 7718, -7718, 12005, -12005},
56  {1536, -1536, 5120, -5120, 9216, -9216, 14336, -14336},
57 };
58 
60 {
62 
63  return 0;
64 }
65 
66 static int qoa_lms_predict(QOAChannel *lms)
67 {
68  int prediction = 0;
69  for (int i = 0; i < QOA_LMS_LEN; i++)
70  prediction += lms->weights[i] * lms->history[i];
71  return prediction >> 13;
72 }
73 
74 static void qoa_lms_update(QOAChannel *lms, int sample, int residual)
75 {
76  int delta = residual >> 4;
77  for (int i = 0; i < QOA_LMS_LEN; i++)
78  lms->weights[i] += lms->history[i] < 0 ? -delta : delta;
79  for (int i = 0; i < QOA_LMS_LEN-1; i++)
80  lms->history[i] = lms->history[i+1];
81  lms->history[QOA_LMS_LEN-1] = sample;
82 }
83 
85  int *got_frame_ptr, AVPacket *avpkt)
86 {
87  QOAContext *s = avctx->priv_data;
88  int ret, frame_size, nb_channels, sample_rate;
89  GetByteContext gb;
90  int16_t *samples;
91 
92  bytestream2_init(&gb, avpkt->data, avpkt->size);
93 
94  nb_channels = bytestream2_get_byte(&gb);
95  sample_rate = bytestream2_get_be24(&gb);
96  if (!sample_rate || !nb_channels)
97  return AVERROR_INVALIDDATA;
98 
99  if (nb_channels != avctx->ch_layout.nb_channels) {
101  av_channel_layout_default(&avctx->ch_layout, nb_channels);
102  if ((ret = av_channel_layout_copy(&frame->ch_layout, &avctx->ch_layout)) < 0)
103  return ret;
104  }
105 
107 
108  frame->nb_samples = bytestream2_get_be16(&gb);
109  frame_size = bytestream2_get_be16(&gb);
110  if (frame_size > avpkt->size)
111  return AVERROR_INVALIDDATA;
112 
113  if (avpkt->size < 8 + QOA_LMS_LEN * 4 * nb_channels +
114  8LL * ((frame->nb_samples + QOA_SLICE_LEN - 1) / QOA_SLICE_LEN) * nb_channels)
115  return AVERROR_INVALIDDATA;
116 
117  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
118  return ret;
119  samples = (int16_t *)frame->data[0];
120 
121  for (int ch = 0; ch < nb_channels; ch++) {
122  QOAChannel *qch = &s->ch[ch];
123 
124  for (int n = 0; n < QOA_LMS_LEN; n++)
125  qch->history[n] = sign_extend(bytestream2_get_be16u(&gb), 16);
126  for (int n = 0; n < QOA_LMS_LEN; n++)
127  qch->weights[n] = sign_extend(bytestream2_get_be16u(&gb), 16);
128  }
129 
130  for (int sample_index = 0; sample_index < frame->nb_samples;
131  sample_index += QOA_SLICE_LEN) {
132  for (int ch = 0; ch < nb_channels; ch++) {
133  QOAChannel *lms = &s->ch[ch];
134  uint64_t slice = bytestream2_get_be64u(&gb);
135  int scalefactor = (slice >> 60) & 0xf;
136  int slice_start = sample_index * nb_channels + ch;
137  int slice_end = av_clip(sample_index + QOA_SLICE_LEN, 0, frame->nb_samples) * nb_channels + ch;
138 
139  for (int si = slice_start; si < slice_end; si += nb_channels) {
140  int predicted = qoa_lms_predict(lms);
141  int quantized = (slice >> 57) & 0x7;
142  int dequantized = qoa_dequant_tab[scalefactor][quantized];
143  int reconstructed = av_clip_int16(predicted + dequantized);
144 
145  samples[si] = reconstructed;
146  slice <<= 3;
147 
148  qoa_lms_update(lms, reconstructed, dequantized);
149  }
150  }
151  }
152 
153  *got_frame_ptr = 1;
154 
155  return avpkt->size;
156 }
157 
159  .p.name = "qoa",
160  CODEC_LONG_NAME("QOA (Quite OK Audio)"),
161  .p.type = AVMEDIA_TYPE_AUDIO,
162  .p.id = AV_CODEC_ID_QOA,
163  .priv_data_size = sizeof(QOAContext),
166  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
168  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16,
170 };
av_clip
#define av_clip
Definition: common.h:98
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1068
GetByteContext
Definition: bytestream.h:33
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
FFCodec
Definition: codec_internal.h:127
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:323
sample_rate
sample_rate
Definition: ffmpeg_filter.c:424
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2111
AVFrame::ch_layout
AVChannelLayout ch_layout
Channel layout of the audio data.
Definition: frame.h:802
slice_start
static int slice_start(SliceContext *sc, VVCContext *s, VVCFrameContext *fc, const CodedBitstreamUnit *unit, const int is_first_slice)
Definition: vvcdec.c:685
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
s
#define s(width, name)
Definition: cbs_vp9.c:198
frame_size
int frame_size
Definition: mxfenc.c:2422
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
slice_end
static int slice_end(AVCodecContext *avctx, AVFrame *pict)
Handle slice ends.
Definition: mpeg12dec.c:1717
qoa_lms_predict
static int qoa_lms_predict(QOAChannel *lms)
Definition: qoadec.c:66
decode.h
get_bits.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
av_clip_int16
#define av_clip_int16
Definition: common.h:113
qoa_lms_update
static void qoa_lms_update(QOAChannel *lms, int sample, int residual)
Definition: qoadec.c:74
QOAChannel
Definition: qoadec.c:31
mathops.h
AV_CODEC_ID_QOA
@ AV_CODEC_ID_QOA
Definition: codec_id.h:548
AV_CODEC_CAP_CHANNEL_CONF
#define AV_CODEC_CAP_CHANNEL_CONF
Codec should fill in channel configuration and samplerate instead of container.
Definition: codec.h:106
QOAContext::ch
QOAChannel ch[256]
Definition: qoadec.c:37
qoa_decode_frame
static int qoa_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt)
Definition: qoadec.c:84
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1618
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:365
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:523
codec_internal.h
AVFrame::sample_rate
int sample_rate
Sample rate of the audio data.
Definition: frame.h:567
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1084
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
sample
#define sample
Definition: flacdsp_template.c:44
QOAChannel::history
int history[QOA_LMS_LEN]
Definition: qoadec.c:32
QOAChannel::weights
int weights[QOA_LMS_LEN]
Definition: qoadec.c:33
prediction
static int64_t prediction(int delta, ChannelContext *c)
Definition: misc4.c:78
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:1033
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:420
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
delta
float delta
Definition: vorbis_enc_data.h:430
xf
#define xf(width, name, var, range_min, range_max, subs,...)
Definition: cbs_av1.c:590
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
qoa_dequant_tab
static const int16_t qoa_dequant_tab[16][8]
Definition: qoadec.c:40
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:445
QOAContext
Definition: qoadec.c:36
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:662
ff_qoa_decoder
const FFCodec ff_qoa_decoder
Definition: qoadec.c:158
sign_extend
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:133
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
av_channel_layout_copy
int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src)
Make a copy of a channel layout.
Definition: channel_layout.c:669
QOA_SLICE_LEN
#define QOA_SLICE_LEN
Definition: qoadec.c:28
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
AVPacket
This structure stores compressed data.
Definition: packet.h:499
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
qoa_decode_init
static av_cold int qoa_decode_init(AVCodecContext *avctx)
Definition: qoadec.c:59
QOA_LMS_LEN
#define QOA_LMS_LEN
Definition: qoadec.c:29