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adxdec.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 "libavutil/intreadwrite.h"
23 #include "avcodec.h"
24 #include "adx.h"
25 #include "get_bits.h"
26 #include "internal.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 
38 {
39  ADXContext *c = avctx->priv_data;
40  int ret, header_size;
41 
42  if (avctx->extradata_size >= 24) {
43  if ((ret = ff_adx_decode_header(avctx, avctx->extradata,
44  avctx->extradata_size, &header_size,
45  c->coeff)) < 0) {
46  av_log(avctx, AV_LOG_ERROR, "error parsing ADX header\n");
47  return AVERROR_INVALIDDATA;
48  }
49  c->channels = avctx->channels;
50  c->header_parsed = 1;
51  }
52 
54 
55  return 0;
56 }
57 
58 /**
59  * Decode 32 samples from 18 bytes.
60  *
61  * A 16-bit scalar value is applied to 32 residuals, which then have a
62  * 2nd-order LPC filter applied to it to form the output signal for a single
63  * channel.
64  */
65 static int adx_decode(ADXContext *c, int16_t *out, int offset,
66  const uint8_t *in, int ch)
67 {
68  ADXChannelState *prev = &c->prev[ch];
69  GetBitContext gb;
70  int scale = AV_RB16(in);
71  int i;
72  int s0, s1, s2, d;
73 
74  /* check if this is an EOF packet */
75  if (scale & 0x8000)
76  return -1;
77 
78  init_get_bits(&gb, in + 2, (BLOCK_SIZE - 2) * 8);
79  out += offset;
80  s1 = prev->s1;
81  s2 = prev->s2;
82  for (i = 0; i < BLOCK_SAMPLES; i++) {
83  d = get_sbits(&gb, 4);
84  s0 = ((d << COEFF_BITS) * scale + c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS;
85  s2 = s1;
86  s1 = av_clip_int16(s0);
87  *out++ = s1;
88  }
89  prev->s1 = s1;
90  prev->s2 = s2;
91 
92  return 0;
93 }
94 
95 static int adx_decode_frame(AVCodecContext *avctx, void *data,
96  int *got_frame_ptr, AVPacket *avpkt)
97 {
98  AVFrame *frame = data;
99  int buf_size = avpkt->size;
100  ADXContext *c = avctx->priv_data;
101  int16_t **samples;
102  int samples_offset;
103  const uint8_t *buf = avpkt->data;
104  const uint8_t *buf_end = buf + avpkt->size;
105  int num_blocks, ch, ret;
106 
107  if (c->eof) {
108  *got_frame_ptr = 0;
109  return buf_size;
110  }
111 
112  if (!c->header_parsed && buf_size >= 2 && AV_RB16(buf) == 0x8000) {
113  int header_size;
114  if ((ret = ff_adx_decode_header(avctx, buf, buf_size, &header_size,
115  c->coeff)) < 0) {
116  av_log(avctx, AV_LOG_ERROR, "error parsing ADX header\n");
117  return AVERROR_INVALIDDATA;
118  }
119  c->channels = avctx->channels;
120  c->header_parsed = 1;
121  if (buf_size < header_size)
122  return AVERROR_INVALIDDATA;
123  buf += header_size;
124  buf_size -= header_size;
125  }
126  if (!c->header_parsed)
127  return AVERROR_INVALIDDATA;
128 
129  /* calculate number of blocks in the packet */
130  num_blocks = buf_size / (BLOCK_SIZE * c->channels);
131 
132  /* if the packet is not an even multiple of BLOCK_SIZE, check for an EOF
133  packet */
134  if (!num_blocks || buf_size % (BLOCK_SIZE * avctx->channels)) {
135  if (buf_size >= 4 && (AV_RB16(buf) & 0x8000)) {
136  c->eof = 1;
137  *got_frame_ptr = 0;
138  return avpkt->size;
139  }
140  return AVERROR_INVALIDDATA;
141  }
142 
143  /* get output buffer */
144  frame->nb_samples = num_blocks * BLOCK_SAMPLES;
145  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
146  return ret;
147  samples = (int16_t **)frame->extended_data;
148  samples_offset = 0;
149 
150  while (num_blocks--) {
151  for (ch = 0; ch < c->channels; ch++) {
152  if (buf_end - buf < BLOCK_SIZE || adx_decode(c, samples[ch], samples_offset, buf, ch)) {
153  c->eof = 1;
154  buf = avpkt->data + avpkt->size;
155  break;
156  }
157  buf_size -= BLOCK_SIZE;
158  buf += BLOCK_SIZE;
159  }
160  if (!c->eof)
161  samples_offset += BLOCK_SAMPLES;
162  }
163 
164  frame->nb_samples = samples_offset;
165  *got_frame_ptr = 1;
166 
167  return buf - avpkt->data;
168 }
169 
170 static void adx_decode_flush(AVCodecContext *avctx)
171 {
172  ADXContext *c = avctx->priv_data;
173  memset(c->prev, 0, sizeof(c->prev));
174  c->eof = 0;
175 }
176 
178  .name = "adpcm_adx",
179  .long_name = NULL_IF_CONFIG_SMALL("SEGA CRI ADX ADPCM"),
180  .type = AVMEDIA_TYPE_AUDIO,
181  .id = AV_CODEC_ID_ADPCM_ADX,
182  .priv_data_size = sizeof(ADXContext),
186  .capabilities = AV_CODEC_CAP_DR1,
187  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
189 };
int ff_adx_decode_header(AVCodecContext *avctx, const uint8_t *buf, int bufsize, int *header_size, int *coeff)
Decode ADX stream header.
Definition: adx.c:38
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:180
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static void flush(AVCodecContext *avctx)
static av_cold int adx_decode_init(AVCodecContext *avctx)
Definition: adxdec.c:37
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1578
int coeff[2]
Definition: adx.h:48
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
AVCodec.
Definition: avcodec.h:3535
#define BLOCK_SAMPLES
Definition: adxdec.c:31
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:245
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2411
uint8_t
#define av_cold
Definition: attributes.h:82
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1757
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1577
bitstream reader API header.
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define COEFF_BITS
Definition: adx.h:51
#define s2
Definition: regdef.h:39
#define BLOCK_SIZE
Definition: adxdec.c:30
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
#define s0
Definition: regdef.h:37
const char * name
Name of the codec implementation.
Definition: avcodec.h:3542
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
static void adx_decode_flush(AVCodecContext *avctx)
Definition: adxdec.c:170
int header_parsed
Definition: adx.h:45
static int adx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: adxdec.c:95
FILE * out
Definition: movenc-test.c:54
static int adx_decode(ADXContext *c, int16_t *out, int offset, const uint8_t *in, int ch)
Decode 32 samples from 18 bytes.
Definition: adxdec.c:65
Libavcodec external API header.
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
main external API structure.
Definition: avcodec.h:1642
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:928
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
void * buf
Definition: avisynth_c.h:553
int extradata_size
Definition: avcodec.h:1758
Definition: adx.h:42
int s2
Definition: adx.h:39
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:418
#define s1
Definition: regdef.h:38
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:722
common internal api header.
static double c[64]
AVCodec ff_adpcm_adx_decoder
Definition: adxdec.c:177
int eof
Definition: adx.h:46
int s1
Definition: adx.h:39
void * priv_data
Definition: avcodec.h:1684
ADXChannelState prev[2]
Definition: adx.h:44
int channels
number of audio channels
Definition: avcodec.h:2404
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:701
signed 16 bits, planar
Definition: samplefmt.h:67
SEGA CRI adx codecs.
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:227
This structure stores compressed data.
Definition: avcodec.h:1554
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:237
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:953
int channels
Definition: adx.h:43