FFmpeg
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 
28 /**
29  * @file
30  * The 3 alphanumeric copyright notices are md5summed they are from the original
31  * implementors. The original code is available from http://code.google.com/p/nelly2pcm/
32  */
33 
35 #include "libavutil/float_dsp.h"
36 #include "libavutil/lfg.h"
37 #include "libavutil/mem_internal.h"
38 
39 #define BITSTREAM_READER_LE
40 #include "avcodec.h"
41 #include "codec_internal.h"
42 #include "decode.h"
43 #include "fft.h"
44 #include "get_bits.h"
45 #include "nellymoser.h"
46 #include "sinewin.h"
47 
48 
49 typedef struct NellyMoserDecodeContext {
53  float scale_bias;
57  float *imdct_out;
58  float *imdct_prev;
60 
62  const unsigned char block[NELLY_BLOCK_LEN],
63  float audio[NELLY_SAMPLES])
64 {
65  int i,j;
66  float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
67  float *aptr, *bptr, *pptr, val, pval;
68  int bits[NELLY_BUF_LEN];
69  unsigned char v;
70 
72 
73  bptr = buf;
74  pptr = pows;
75  val = ff_nelly_init_table[get_bits(&s->gb, 6)];
76  for (i=0 ; i<NELLY_BANDS ; i++) {
77  if (i > 0)
78  val += ff_nelly_delta_table[get_bits(&s->gb, 5)];
79  pval = -exp2(val/2048) * s->scale_bias;
80  for (j = 0; j < ff_nelly_band_sizes_table[i]; j++) {
81  *bptr++ = val;
82  *pptr++ = pval;
83  }
84 
85  }
86 
88 
89  for (i = 0; i < 2; i++) {
90  aptr = audio + i * NELLY_BUF_LEN;
91 
94 
95  for (j = 0; j < NELLY_FILL_LEN; j++) {
96  if (bits[j] <= 0) {
97  aptr[j] = M_SQRT1_2*pows[j];
98  if (av_lfg_get(&s->random_state) & 1)
99  aptr[j] *= -1.0;
100  } else {
101  v = get_bits(&s->gb, bits[j]);
102  aptr[j] = ff_nelly_dequantization_table[(1<<bits[j])-1+v]*pows[j];
103  }
104  }
105  memset(&aptr[NELLY_FILL_LEN], 0,
106  (NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));
107 
108  s->imdct_ctx.imdct_half(&s->imdct_ctx, s->imdct_out, aptr);
109  s->fdsp->vector_fmul_window(aptr, s->imdct_prev + NELLY_BUF_LEN / 2,
110  s->imdct_out, ff_sine_128,
111  NELLY_BUF_LEN / 2);
112  FFSWAP(float *, s->imdct_out, s->imdct_prev);
113  }
114 }
115 
116 static av_cold int decode_init(AVCodecContext * avctx) {
118 
119  s->avctx = avctx;
120  s->imdct_out = s->imdct_buf[0];
121  s->imdct_prev = s->imdct_buf[1];
122  av_lfg_init(&s->random_state, 0);
123  ff_mdct_init(&s->imdct_ctx, 8, 1, 1.0);
124 
126  if (!s->fdsp)
127  return AVERROR(ENOMEM);
128 
129  s->scale_bias = 1.0/(32768*8);
130  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
131 
134 
135  /* Generate overlap window */
137 
138  return 0;
139 }
140 
142  int *got_frame_ptr, AVPacket *avpkt)
143 {
144  const uint8_t *buf = avpkt->data;
145  int buf_size = avpkt->size;
147  int blocks, i, ret;
148  float *samples_flt;
149 
150  blocks = buf_size / NELLY_BLOCK_LEN;
151 
152  if (blocks <= 0) {
153  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
154  return AVERROR_INVALIDDATA;
155  }
156 
157  if (buf_size % NELLY_BLOCK_LEN) {
158  av_log(avctx, AV_LOG_WARNING, "Leftover bytes: %d.\n",
159  buf_size % NELLY_BLOCK_LEN);
160  }
161 
162  /* get output buffer */
163  frame->nb_samples = NELLY_SAMPLES * blocks;
164  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
165  return ret;
166  samples_flt = (float *)frame->data[0];
167 
168  for (i=0 ; i<blocks ; i++) {
169  nelly_decode_block(s, buf, samples_flt);
170  samples_flt += NELLY_SAMPLES;
171  buf += NELLY_BLOCK_LEN;
172  }
173 
174  *got_frame_ptr = 1;
175 
176  return buf_size;
177 }
178 
179 static av_cold int decode_end(AVCodecContext * avctx) {
181 
182  ff_mdct_end(&s->imdct_ctx);
183  av_freep(&s->fdsp);
184 
185  return 0;
186 }
187 
189  .p.name = "nellymoser",
190  CODEC_LONG_NAME("Nellymoser Asao"),
191  .p.type = AVMEDIA_TYPE_AUDIO,
192  .p.id = AV_CODEC_ID_NELLYMOSER,
193  .priv_data_size = sizeof(NellyMoserDecodeContext),
194  .init = decode_init,
195  .close = decode_end,
198  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
200 };
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:291
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
NELLY_HEADER_BITS
#define NELLY_HEADER_BITS
Definition: nellymoser.h:41
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
mem_internal.h
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: nellymoserdec.c:116
av_lfg_init
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
nellymoser.h
NELLY_FILL_LEN
#define NELLY_FILL_LEN
Definition: nellymoser.h:44
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVPacket::data
uint8_t * data
Definition: packet.h:374
NELLY_BLOCK_LEN
#define NELLY_BLOCK_LEN
Definition: nellymoser.h:40
ff_mdct_init
#define ff_mdct_init
Definition: fft.h:154
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:356
FFCodec
Definition: codec_internal.h:119
NellyMoserDecodeContext::imdct_ctx
FFTContext imdct_ctx
Definition: nellymoserdec.c:55
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:649
ff_nellymoser_decoder
const FFCodec ff_nellymoser_decoder
Definition: nellymoserdec.c:188
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:123
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2059
ff_nelly_band_sizes_table
const uint8_t ff_nelly_band_sizes_table[NELLY_BANDS]
Definition: nellymoser.c:68
GetBitContext
Definition: get_bits.h:61
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:478
val
static double val(void *priv, double ch)
Definition: aeval.c:77
ff_nelly_dequantization_table
const float ff_nelly_dequantization_table[127]
Definition: nellymoser.c:41
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:298
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_lfg_get
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
NELLY_BANDS
#define NELLY_BANDS
Definition: nellymoser.h:39
lfg.h
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts_bsf.c:363
bits
uint8_t bits
Definition: vp3data.h:141
decode.h
get_bits.h
ff_nelly_init_table
const uint16_t ff_nelly_init_table[64]
Definition: nellymoser.c:72
NellyMoserDecodeContext::imdct_prev
float * imdct_prev
Definition: nellymoserdec.c:58
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:264
ff_nelly_delta_table
const int16_t ff_nelly_delta_table[32]
Definition: nellymoser.c:81
NellyMoserDecodeContext::random_state
AVLFG random_state
Definition: nellymoserdec.c:51
NellyMoserDecodeContext::imdct_buf
float imdct_buf[2][NELLY_BUF_LEN]
Definition: nellymoserdec.c:56
NELLY_DETAIL_BITS
#define NELLY_DETAIL_BITS
Definition: nellymoser.h:42
NellyMoserDecodeContext
Definition: nellymoserdec.c:49
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: nellymoserdec.c:179
float_dsp.h
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:630
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:109
AVLFG
Context structure for the Lagged Fibonacci PRNG.
Definition: lfg.h:33
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1450
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:375
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:293
codec_internal.h
NellyMoserDecodeContext::fdsp
AVFloatDSPContext * fdsp
Definition: nellymoserdec.c:54
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:1023
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
ff_mdct_end
#define ff_mdct_end
Definition: fft.h:155
NELLY_BUF_LEN
#define NELLY_BUF_LEN
Definition: nellymoser.h:43
AVFloatDSPContext
Definition: float_dsp.h:24
sinewin.h
NellyMoserDecodeContext::imdct_out
float * imdct_out
Definition: nellymoserdec.c:57
NELLY_SAMPLES
#define NELLY_SAMPLES
Definition: nellymoser.h:48
DECLARE_ALIGNED
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:116
FFTContext
Definition: fft.h:76
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
exp2
#define exp2(x)
Definition: libm.h:288
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
NellyMoserDecodeContext::scale_bias
float scale_bias
Definition: nellymoserdec.c:53
avcodec.h
ret
ret
Definition: filter_design.txt:187
NellyMoserDecodeContext::gb
GetBitContext gb
Definition: nellymoserdec.c:52
FFSWAP
#define FFSWAP(type, a, b)
Definition: macros.h:52
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
decode_tag
static int decode_tag(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt)
Definition: nellymoserdec.c:141
NellyMoserDecodeContext::avctx
AVCodecContext * avctx
Definition: nellymoserdec.c:50
M_SQRT1_2
#define M_SQRT1_2
Definition: mathematics.h:58
fft.h
AVCodecContext
main external API structure.
Definition: avcodec.h:398
channel_layout.h
ff_init_ff_sine_windows
void ff_init_ff_sine_windows(int index)
initialize the specified entry of ff_sine_windows
Definition: sinewin_tablegen.h:101
nelly_decode_block
static void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NELLY_BLOCK_LEN], float audio[NELLY_SAMPLES])
Definition: nellymoserdec.c:61
AV_CODEC_CAP_PARAM_CHANGE
#define AV_CODEC_CAP_PARAM_CHANGE
Codec supports changed parameters at any point.
Definition: codec.h:121
AV_CODEC_FLAG_BITEXACT
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:288
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:425
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
avpriv_float_dsp_alloc
av_cold AVFloatDSPContext * avpriv_float_dsp_alloc(int bit_exact)
Allocate a float DSP context.
Definition: float_dsp.c:135
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:60
AV_CODEC_ID_NELLYMOSER
@ AV_CODEC_ID_NELLYMOSER
Definition: codec_id.h:467
ff_nelly_get_sample_bits
void ff_nelly_get_sample_bits(const float *buf, int *bits)
Definition: nellymoser.c:118