FFmpeg  4.4.6
adxenc.c
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1 /*
2  * ADX ADPCM codecs
3  * Copyright (c) 2001,2003 BERO
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 "avcodec.h"
23 #include "adx.h"
24 #include "bytestream.h"
25 #include "internal.h"
26 #include "put_bits.h"
27 
28 /**
29  * @file
30  * SEGA CRI adx codecs.
31  *
32  * Reference documents:
33  * http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html
34  * adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/
35  */
36 
37 static void adx_encode(ADXContext *c, uint8_t *adx, const int16_t *wav,
38  ADXChannelState *prev, int channels)
39 {
40  PutBitContext pb;
41  int scale;
42  int i, j;
43  int s0, s1, s2, d;
44  int max = 0;
45  int min = 0;
46 
47  s1 = prev->s1;
48  s2 = prev->s2;
49  for (i = 0, j = 0; j < 32; i += channels, j++) {
50  s0 = wav[i];
51  d = s0 + ((-c->coeff[0] * s1 - c->coeff[1] * s2) >> COEFF_BITS);
52  if (max < d)
53  max = d;
54  if (min > d)
55  min = d;
56  s2 = s1;
57  s1 = s0;
58  }
59 
60  if (max == 0 && min == 0) {
61  prev->s1 = s1;
62  prev->s2 = s2;
63  memset(adx, 0, BLOCK_SIZE);
64  return;
65  }
66 
67  if (max / 7 > -min / 8)
68  scale = max / 7;
69  else
70  scale = -min / 8;
71 
72  if (scale == 0)
73  scale = 1;
74 
75  AV_WB16(adx, scale);
76 
77  init_put_bits(&pb, adx + 2, 16);
78 
79  s1 = prev->s1;
80  s2 = prev->s2;
81  for (i = 0, j = 0; j < 32; i += channels, j++) {
82  d = wav[i] + ((-c->coeff[0] * s1 - c->coeff[1] * s2) >> COEFF_BITS);
83 
84  d = av_clip_intp2(ROUNDED_DIV(d, scale), 3);
85 
86  put_sbits(&pb, 4, d);
87 
88  s0 = d * scale + ((c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS);
89  s2 = s1;
90  s1 = s0;
91  }
92  prev->s1 = s1;
93  prev->s2 = s2;
94 
95  flush_put_bits(&pb);
96 }
97 
98 #define HEADER_SIZE 36
99 
100 static int adx_encode_header(AVCodecContext *avctx, uint8_t *buf, int bufsize)
101 {
102  ADXContext *c = avctx->priv_data;
103 
104  bytestream_put_be16(&buf, 0x8000); /* header signature */
105  bytestream_put_be16(&buf, HEADER_SIZE - 4); /* copyright offset */
106  bytestream_put_byte(&buf, 3); /* encoding */
107  bytestream_put_byte(&buf, BLOCK_SIZE); /* block size */
108  bytestream_put_byte(&buf, 4); /* sample size */
109  bytestream_put_byte(&buf, avctx->channels); /* channels */
110  bytestream_put_be32(&buf, avctx->sample_rate); /* sample rate */
111  bytestream_put_be32(&buf, 0); /* total sample count */
112  bytestream_put_be16(&buf, c->cutoff); /* cutoff frequency */
113  bytestream_put_byte(&buf, 3); /* version */
114  bytestream_put_byte(&buf, 0); /* flags */
115  bytestream_put_be32(&buf, 0); /* unknown */
116  bytestream_put_be32(&buf, 0); /* loop enabled */
117  bytestream_put_be16(&buf, 0); /* padding */
118  bytestream_put_buffer(&buf, "(c)CRI", 6); /* copyright signature */
119 
120  return HEADER_SIZE;
121 }
122 
124 {
125  ADXContext *c = avctx->priv_data;
126 
127  if (avctx->channels > 2) {
128  av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");
129  return AVERROR(EINVAL);
130  }
131  avctx->frame_size = BLOCK_SAMPLES;
132 
133  /* the cutoff can be adjusted, but this seems to work pretty well */
134  c->cutoff = 500;
135  ff_adx_calculate_coeffs(c->cutoff, avctx->sample_rate, COEFF_BITS, c->coeff);
136 
137  return 0;
138 }
139 
140 static int adx_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
141  const AVFrame *frame, int *got_packet_ptr)
142 {
143  ADXContext *c = avctx->priv_data;
144  const int16_t *samples = frame ? (const int16_t *)frame->data[0] : NULL;
145  uint8_t *dst;
146  int ch, out_size, ret;
147 
148  if (!samples) {
149  if (c->eof)
150  return 0;
151  if ((ret = ff_alloc_packet2(avctx, avpkt, 18, 0)) < 0)
152  return ret;
153  c->eof = 1;
154  dst = avpkt->data;
155  bytestream_put_be16(&dst, 0x8001);
156  bytestream_put_be16(&dst, 0x000E);
157  bytestream_put_be64(&dst, 0x0);
158  bytestream_put_be32(&dst, 0x0);
159  bytestream_put_be16(&dst, 0x0);
160  *got_packet_ptr = 1;
161  return 0;
162  }
163 
164  out_size = BLOCK_SIZE * avctx->channels + !c->header_parsed * HEADER_SIZE;
165  if ((ret = ff_alloc_packet2(avctx, avpkt, out_size, 0)) < 0)
166  return ret;
167  dst = avpkt->data;
168 
169  if (!c->header_parsed) {
170  int hdrsize;
171  if ((hdrsize = adx_encode_header(avctx, dst, avpkt->size)) < 0) {
172  av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");
173  return AVERROR(EINVAL);
174  }
175  dst += hdrsize;
176  c->header_parsed = 1;
177  }
178 
179  for (ch = 0; ch < avctx->channels; ch++) {
180  adx_encode(c, dst, samples + ch, &c->prev[ch], avctx->channels);
181  dst += BLOCK_SIZE;
182  }
183 
184  avpkt->pts = frame->pts;
185  avpkt->duration = frame->nb_samples;
186  *got_packet_ptr = 1;
187  return 0;
188 }
189 
191  .name = "adpcm_adx",
192  .long_name = NULL_IF_CONFIG_SMALL("SEGA CRI ADX ADPCM"),
193  .type = AVMEDIA_TYPE_AUDIO,
194  .id = AV_CODEC_ID_ADPCM_ADX,
195  .priv_data_size = sizeof(ADXContext),
197  .encode2 = adx_encode_frame,
198  .capabilities = AV_CODEC_CAP_DELAY,
199  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16,
201 };
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:925
void ff_adx_calculate_coeffs(int cutoff, int sample_rate, int bits, int *coeff)
Calculate LPC coefficients based on cutoff frequency and sample rate.
Definition: adx.c:26
SEGA CRI adx codecs.
#define COEFF_BITS
Definition: adx.h:51
#define BLOCK_SAMPLES
Definition: adx.h:54
#define BLOCK_SIZE
Definition: adx.h:53
#define HEADER_SIZE
Definition: adxenc.c:98
static int adx_encode_header(AVCodecContext *avctx, uint8_t *buf, int bufsize)
Definition: adxenc.c:100
static void adx_encode(ADXContext *c, uint8_t *adx, const int16_t *wav, ADXChannelState *prev, int channels)
Definition: adxenc.c:37
static av_cold int adx_encode_init(AVCodecContext *avctx)
Definition: adxenc.c:123
AVCodec ff_adpcm_adx_encoder
Definition: adxenc.c:190
static int adx_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: adxenc.c:140
channels
Definition: aptx.h:33
#define av_cold
Definition: attributes.h:88
uint8_t
Libavcodec external API header.
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
Definition: bytestream.h:372
#define av_clip_intp2
Definition: common.h:143
#define ROUNDED_DIV(a, b)
Definition: common.h:56
#define NULL
Definition: coverity.c:32
#define max(a, b)
Definition: cuda_runtime.h:33
static AVFrame * frame
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:33
#define AV_CODEC_CAP_DELAY
Encoder or decoder requires flushing with NULL input at the end in order to give the complete and cor...
Definition: codec.h:77
@ AV_CODEC_ID_ADPCM_ADX
Definition: codec_id.h:362
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:61
int i
Definition: input.c:407
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
bitstream writer API
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:253
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:57
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:110
#define s1
Definition: regdef.h:38
#define s2
Definition: regdef.h:39
#define s0
Definition: regdef.h:37
int s2
Definition: adx.h:39
int s1
Definition: adx.h:39
Definition: adx.h:42
main external API structure.
Definition: avcodec.h:536
int sample_rate
samples per second
Definition: avcodec.h:1196
int channels
number of audio channels
Definition: avcodec.h:1197
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1216
void * priv_data
Definition: avcodec.h:563
AVCodec.
Definition: codec.h:197
const char * name
Name of the codec implementation.
Definition: codec.h:204
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:384
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:411
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:332
This structure stores compressed data.
Definition: packet.h:346
int size
Definition: packet.h:370
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
uint8_t * data
Definition: packet.h:369
#define av_log(a,...)
int out_size
Definition: movenc.c:55
if(ret< 0)
Definition: vf_mcdeint.c:282
float min
static double c[64]