nellymoserdec.c
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1 /*
2  * NellyMoser audio decoder
3  * Copyright (c) 2007 a840bda5870ba11f19698ff6eb9581dfb0f95fa5,
4  * 539459aeb7d425140b62a3ec7dbf6dc8e408a306, and
5  * 520e17cd55896441042b14df2566a6eb610ed444
6  * Copyright (c) 2007 Loic Minier <lool at dooz.org>
7  * Benjamin Larsson
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
10  * copy of this software and associated documentation files (the "Software"),
11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
24  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25  * DEALINGS IN THE SOFTWARE.
26  */
27 
35 #include "libavutil/lfg.h"
36 #include "libavutil/random_seed.h"
37 #include "avcodec.h"
38 #include "dsputil.h"
39 #include "fft.h"
40 #include "fmtconvert.h"
41 #include "internal.h"
42 #include "nellymoser.h"
43 #include "sinewin.h"
44 
45 #define BITSTREAM_READER_LE
46 #include "get_bits.h"
47 
48 
49 typedef struct NellyMoserDecodeContext {
54  float scale_bias;
58  float *imdct_out;
59  float *imdct_prev;
61 
63  const unsigned char block[NELLY_BLOCK_LEN],
64  float audio[NELLY_SAMPLES])
65 {
66  int i,j;
67  float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
68  float *aptr, *bptr, *pptr, val, pval;
69  int bits[NELLY_BUF_LEN];
70  unsigned char v;
71 
72  init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
73 
74  bptr = buf;
75  pptr = pows;
76  val = ff_nelly_init_table[get_bits(&s->gb, 6)];
77  for (i=0 ; i<NELLY_BANDS ; i++) {
78  if (i > 0)
79  val += ff_nelly_delta_table[get_bits(&s->gb, 5)];
80  pval = -pow(2, val/2048) * s->scale_bias;
81  for (j = 0; j < ff_nelly_band_sizes_table[i]; j++) {
82  *bptr++ = val;
83  *pptr++ = pval;
84  }
85 
86  }
87 
88  ff_nelly_get_sample_bits(buf, bits);
89 
90  for (i = 0; i < 2; i++) {
91  aptr = audio + i * NELLY_BUF_LEN;
92 
93  init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
95 
96  for (j = 0; j < NELLY_FILL_LEN; j++) {
97  if (bits[j] <= 0) {
98  aptr[j] = M_SQRT1_2*pows[j];
99  if (av_lfg_get(&s->random_state) & 1)
100  aptr[j] *= -1.0;
101  } else {
102  v = get_bits(&s->gb, bits[j]);
103  aptr[j] = ff_nelly_dequantization_table[(1<<bits[j])-1+v]*pows[j];
104  }
105  }
106  memset(&aptr[NELLY_FILL_LEN], 0,
107  (NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));
108 
109  s->imdct_ctx.imdct_half(&s->imdct_ctx, s->imdct_out, aptr);
110  s->dsp.vector_fmul_window(aptr, s->imdct_prev + NELLY_BUF_LEN/2, s->imdct_out, ff_sine_128, NELLY_BUF_LEN/2);
111  FFSWAP(float *, s->imdct_out, s->imdct_prev);
112  }
113 }
114 
115 static av_cold int decode_init(AVCodecContext * avctx) {
117 
118  s->avctx = avctx;
119  s->imdct_out = s->imdct_buf[0];
120  s->imdct_prev = s->imdct_buf[1];
121  av_lfg_init(&s->random_state, 0);
122  ff_mdct_init(&s->imdct_ctx, 8, 1, 1.0);
123 
124  ff_dsputil_init(&s->dsp, avctx);
125 
126  s->scale_bias = 1.0/(32768*8);
127  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
128 
129  /* Generate overlap window */
130  if (!ff_sine_128[127])
132 
133  avctx->channels = 1;
135 
137  avctx->coded_frame = &s->frame;
138 
139  return 0;
140 }
141 
142 static int decode_tag(AVCodecContext *avctx, void *data,
143  int *got_frame_ptr, AVPacket *avpkt)
144 {
145  const uint8_t *buf = avpkt->data;
146  int buf_size = avpkt->size;
148  int blocks, i, ret;
149  float *samples_flt;
150 
151  blocks = buf_size / NELLY_BLOCK_LEN;
152  if (blocks <= 0) {
153  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
154  return AVERROR_INVALIDDATA;
155  }
156  if (buf_size % NELLY_BLOCK_LEN) {
157  av_log(avctx, AV_LOG_WARNING, "Leftover bytes: %d.\n",
158  buf_size % NELLY_BLOCK_LEN);
159  }
160  /* Normal numbers of blocks for sample rates:
161  * 8000 Hz - 1
162  * 11025 Hz - 2
163  * 16000 Hz - 3
164  * 22050 Hz - 4
165  * 44100 Hz - 8
166  */
167 
168  /* get output buffer */
169  s->frame.nb_samples = NELLY_SAMPLES * blocks;
170  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
171  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
172  return ret;
173  }
174  samples_flt = (float *)s->frame.data[0];
175 
176  for (i=0 ; i<blocks ; i++) {
177  nelly_decode_block(s, buf, samples_flt);
178  samples_flt += NELLY_SAMPLES;
179  buf += NELLY_BLOCK_LEN;
180  }
181 
182  *got_frame_ptr = 1;
183  *(AVFrame *)data = s->frame;
184 
185  return buf_size;
186 }
187 
188 static av_cold int decode_end(AVCodecContext * avctx) {
190 
191  ff_mdct_end(&s->imdct_ctx);
192 
193  return 0;
194 }
195 
197  .name = "nellymoser",
198  .type = AVMEDIA_TYPE_AUDIO,
200  .priv_data_size = sizeof(NellyMoserDecodeContext),
201  .init = decode_init,
202  .close = decode_end,
203  .decode = decode_tag,
204  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_PARAM_CHANGE,
205  .long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
206  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
208 };
Definition: lfg.h:25
void(* vector_fmul_window)(float *dst, const float *src0, const float *src1, const float *win, int len)
Definition: dsputil.h:358
av_cold void ff_dsputil_init(DSPContext *c, AVCodecContext *avctx)
Definition: dsputil.c:2656
This structure describes decoded (raw) audio or video data.
Definition: avcodec.h:989
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:237
static void skip_bits_long(GetBitContext *s, int n)
Definition: get_bits.h:197
AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2725
AVCodecContext * avctx
Definition: nellymoserdec.c:50
int size
Definition: avcodec.h:916
const float ff_nelly_dequantization_table[127]
Definition: nellymoser.c:41
static av_cold int decode_end(AVCodecContext *avctx)
AVCodec.
Definition: avcodec.h:2960
#define NELLY_DETAIL_BITS
Definition: nellymoser.h:42
const uint16_t ff_nelly_init_table[64]
Definition: nellymoser.c:72
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:228
uint8_t bits
Definition: crc.c:31
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2112
uint8_t
struct NellyMoserDecodeContext NellyMoserDecodeContext
const char data[16]
Definition: mxf.c:66
uint8_t * data
Definition: avcodec.h:915
bitstream reader API header.
static int init(AVCodecParserContext *s)
Definition: h264_parser.c:335
static int decode_tag(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
const char * name
Name of the codec implementation.
Definition: avcodec.h:2967
#define ff_mdct_init
Definition: fft.h:146
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2165
AVCodec ff_nellymoser_decoder
Definition: fft.h:62
audio channel layout utility functions
static DCTELEM block[64]
Definition: dct-test.c:169
#define NELLY_BLOCK_LEN
Definition: nellymoser.h:40
const uint8_t ff_nelly_band_sizes_table[NELLY_BANDS]
Definition: nellymoser.c:68
#define NELLY_HEADER_BITS
Definition: nellymoser.h:41
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame)
Get a buffer for a frame.
Definition: utils.c:464
static void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NELLY_BLOCK_LEN], float audio[NELLY_SAMPLES])
Definition: nellymoserdec.c:62
static av_cold int decode_init(AVCodecContext *avctx)
external API header
AV_SAMPLE_FMT_NONE
Definition: avconv_filter.c:63
main external API structure.
Definition: avcodec.h:1339
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:326
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:38
void(* imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:82
void avcodec_get_frame_defaults(AVFrame *frame)
Set the fields of the given AVFrame to default values.
Definition: utils.c:604
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:372
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:30
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: avcodec.h:997
float imdct_buf[2][NELLY_BUF_LEN]
Definition: nellymoserdec.c:57
common internal api header.
#define ff_mdct_end
Definition: fft.h:147
#define NELLY_BUF_LEN
Definition: nellymoser.h:43
AVSampleFormat
Audio Sample Formats.
Definition: samplefmt.h:49
DSP utils.
void * priv_data
Definition: avcodec.h:1382
int channels
number of audio channels
Definition: avcodec.h:2105
const int16_t ff_nelly_delta_table[32]
Definition: nellymoser.c:81
#define NELLY_BANDS
Definition: nellymoser.h:39
void ff_nelly_get_sample_bits(const float *buf, int *bits)
Definition: nellymoser.c:118
#define AV_CH_LAYOUT_MONO
The 3 alphanumeric copyright notices are md5summed they are from the original implementors.
#define NELLY_SAMPLES
Definition: nellymoser.h:48
This structure stores compressed data.
Definition: avcodec.h:898
#define NELLY_FILL_LEN
Definition: nellymoser.h:44
int nb_samples
number of audio samples (per channel) described by this frame
Definition: avcodec.h:1042
for(j=16;j >0;--j)
void ff_init_ff_sine_windows(int index)
initialize the specified entry of ff_sine_windows
DSPContext.
Definition: dsputil.h:194