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/random_seed.h"
38 
39 #define BITSTREAM_READER_LE
40 #include "avcodec.h"
41 #include "fft.h"
42 #include "get_bits.h"
43 #include "internal.h"
44 #include "nellymoser.h"
45 #include "sinewin.h"
46 
47 
48 typedef struct NellyMoserDecodeContext {
52  float scale_bias;
56  float *imdct_out;
57  float *imdct_prev;
59 
61  const unsigned char block[NELLY_BLOCK_LEN],
62  float audio[NELLY_SAMPLES])
63 {
64  int i,j;
65  float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
66  float *aptr, *bptr, *pptr, val, pval;
67  int bits[NELLY_BUF_LEN];
68  unsigned char v;
69 
71 
72  bptr = buf;
73  pptr = pows;
74  val = ff_nelly_init_table[get_bits(&s->gb, 6)];
75  for (i=0 ; i<NELLY_BANDS ; i++) {
76  if (i > 0)
77  val += ff_nelly_delta_table[get_bits(&s->gb, 5)];
78  pval = -exp2(val/2048) * s->scale_bias;
79  for (j = 0; j < ff_nelly_band_sizes_table[i]; j++) {
80  *bptr++ = val;
81  *pptr++ = pval;
82  }
83 
84  }
85 
87 
88  for (i = 0; i < 2; i++) {
89  aptr = audio + i * NELLY_BUF_LEN;
90 
93 
94  for (j = 0; j < NELLY_FILL_LEN; j++) {
95  if (bits[j] <= 0) {
96  aptr[j] = M_SQRT1_2*pows[j];
97  if (av_lfg_get(&s->random_state) & 1)
98  aptr[j] *= -1.0;
99  } else {
100  v = get_bits(&s->gb, bits[j]);
101  aptr[j] = ff_nelly_dequantization_table[(1<<bits[j])-1+v]*pows[j];
102  }
103  }
104  memset(&aptr[NELLY_FILL_LEN], 0,
105  (NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));
106 
107  s->imdct_ctx.imdct_half(&s->imdct_ctx, s->imdct_out, aptr);
108  s->fdsp->vector_fmul_window(aptr, s->imdct_prev + NELLY_BUF_LEN / 2,
109  s->imdct_out, ff_sine_128,
110  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 
125  if (!s->fdsp)
126  return AVERROR(ENOMEM);
127 
128  s->scale_bias = 1.0/(32768*8);
129  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
130 
131  /* Generate overlap window */
132  if (!ff_sine_128[127])
134 
135  avctx->channels = 1;
137 
138  return 0;
139 }
140 
141 static int decode_tag(AVCodecContext *avctx, void *data,
142  int *got_frame_ptr, AVPacket *avpkt)
143 {
144  AVFrame *frame = data;
145  const uint8_t *buf = avpkt->data;
146  const uint8_t *side=av_packet_get_side_data(avpkt, 'F', NULL);
147  int buf_size = avpkt->size;
149  int blocks, i, ret;
150  float *samples_flt;
151 
152  blocks = buf_size / NELLY_BLOCK_LEN;
153 
154  if (blocks <= 0) {
155  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
156  return AVERROR_INVALIDDATA;
157  }
158 
159  if (buf_size % NELLY_BLOCK_LEN) {
160  av_log(avctx, AV_LOG_WARNING, "Leftover bytes: %d.\n",
161  buf_size % NELLY_BLOCK_LEN);
162  }
163  /* Normal numbers of blocks for sample rates:
164  * 8000 Hz - 1
165  * 11025 Hz - 2
166  * 16000 Hz - 3
167  * 22050 Hz - 4
168  * 44100 Hz - 8
169  */
170  if(side && blocks>1 && avctx->sample_rate%11025==0 && (1<<((side[0]>>2)&3)) == blocks)
171  avctx->sample_rate= 11025*(blocks/2);
172 
173  /* get output buffer */
174  frame->nb_samples = NELLY_SAMPLES * blocks;
175  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
176  return ret;
177  samples_flt = (float *)frame->data[0];
178 
179  for (i=0 ; i<blocks ; i++) {
180  nelly_decode_block(s, buf, samples_flt);
181  samples_flt += NELLY_SAMPLES;
182  buf += NELLY_BLOCK_LEN;
183  }
184 
185  *got_frame_ptr = 1;
186 
187  return buf_size;
188 }
189 
190 static av_cold int decode_end(AVCodecContext * avctx) {
192 
193  ff_mdct_end(&s->imdct_ctx);
194  av_freep(&s->fdsp);
195 
196  return 0;
197 }
198 
200  .name = "nellymoser",
201  .long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
202  .type = AVMEDIA_TYPE_AUDIO,
204  .priv_data_size = sizeof(NellyMoserDecodeContext),
205  .init = decode_init,
206  .close = decode_end,
207  .decode = decode_tag,
209  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
211 };
AVCodec
AVCodec.
Definition: codec.h:190
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:182
NELLY_HEADER_BITS
#define NELLY_HEADER_BITS
Definition: nellymoser.h:41
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
ff_init_ff_sine_windows
void AAC_RENAME() ff_init_ff_sine_windows(int index)
initialize the specified entry of ff_sine_windows
Definition: sinewin_tablegen.h:76
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
AVCodecContext::channel_layout
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1237
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: nellymoserdec.c:115
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1186
FFSWAP
#define FFSWAP(type, a, b)
Definition: common.h:99
av_lfg_init
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:716
nellymoser.h
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:85
NELLY_FILL_LEN
#define NELLY_FILL_LEN
Definition: nellymoser.h:44
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:355
data
const char data[16]
Definition: mxf.c:91
NELLY_BLOCK_LEN
#define NELLY_BLOCK_LEN
Definition: nellymoser.h:40
ff_mdct_init
#define ff_mdct_init
Definition: fft.h:169
NellyMoserDecodeContext::imdct_ctx
FFTContext imdct_ctx
Definition: nellymoserdec.c:54
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
decode_tag
static int decode_tag(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: nellymoserdec.c:141
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
ff_nelly_band_sizes_table
const uint8_t ff_nelly_band_sizes_table[NELLY_BANDS]
Definition: nellymoser.c:66
GetBitContext
Definition: get_bits.h:61
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:606
val
static double val(void *priv, double ch)
Definition: aeval.c:76
ff_nelly_dequantization_table
const float ff_nelly_dequantization_table[127]
Definition: nellymoser.c:39
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_cold
#define av_cold
Definition: attributes.h:90
ff_nellymoser_decoder
AVCodec ff_nellymoser_decoder
Definition: nellymoserdec.c:199
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
s
#define s(width, name)
Definition: cbs_vp9.c:257
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
bits
uint8_t bits
Definition: vp3data.h:202
get_bits.h
ff_nelly_init_table
const uint16_t ff_nelly_init_table[64]
Definition: nellymoser.c:70
NellyMoserDecodeContext::imdct_prev
float * imdct_prev
Definition: nellymoserdec.c:57
av_packet_get_side_data
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:353
ff_nelly_delta_table
const int16_t ff_nelly_delta_table[32]
Definition: nellymoser.c:79
NellyMoserDecodeContext::random_state
AVLFG random_state
Definition: nellymoserdec.c:50
NellyMoserDecodeContext::imdct_buf
float imdct_buf[2][NELLY_BUF_LEN]
Definition: nellymoserdec.c:55
NULL
#define NULL
Definition: coverity.c:32
NELLY_DETAIL_BITS
#define NELLY_DETAIL_BITS
Definition: nellymoser.h:42
NellyMoserDecodeContext
Definition: nellymoserdec.c:48
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: nellymoserdec.c:190
float_dsp.h
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
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:1854
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:50
AVPacket::size
int size
Definition: packet.h:356
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
NellyMoserDecodeContext::fdsp
AVFloatDSPContext * fdsp
Definition: nellymoserdec.c:53
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1194
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
ff_mdct_end
#define ff_mdct_end
Definition: fft.h:170
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:56
NELLY_SAMPLES
#define NELLY_SAMPLES
Definition: nellymoser.h:48
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:1187
DECLARE_ALIGNED
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:112
FFTContext
Definition: fft.h:88
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
exp2
#define exp2(x)
Definition: libm.h:288
uint8_t
uint8_t
Definition: audio_convert.c:194
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:197
NellyMoserDecodeContext::scale_bias
float scale_bias
Definition: nellymoserdec.c:52
avcodec.h
ret
ret
Definition: filter_design.txt:187
NellyMoserDecodeContext::gb
GetBitContext gb
Definition: nellymoserdec.c:51
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
NellyMoserDecodeContext::avctx
AVCodecContext * avctx
Definition: nellymoserdec.c:49
M_SQRT1_2
#define M_SQRT1_2
Definition: mathematics.h:58
fft.h
AVCodecContext
main external API structure.
Definition: avcodec.h:526
random_seed.h
channel_layout.h
nelly_decode_block
static void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NELLY_BLOCK_LEN], float audio[NELLY_SAMPLES])
Definition: nellymoserdec.c:60
AV_CODEC_CAP_PARAM_CHANGE
#define AV_CODEC_CAP_PARAM_CHANGE
Codec supports changed parameters at any point.
Definition: codec.h:114
AV_CODEC_FLAG_BITEXACT
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:333
AVPacket
This structure stores compressed data.
Definition: packet.h:332
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:553
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
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:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:63
AV_CODEC_ID_NELLYMOSER
@ AV_CODEC_ID_NELLYMOSER
Definition: codec_id.h:443
ff_nelly_get_sample_bits
void ff_nelly_get_sample_bits(const float *buf, int *bits)
Definition: nellymoser.c:116