1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/*
* NellyMoser audio decoder
* Copyright (c) 2007 a840bda5870ba11f19698ff6eb9581dfb0f95fa5,
* 539459aeb7d425140b62a3ec7dbf6dc8e408a306, and
* 520e17cd55896441042b14df2566a6eb610ed444
* Copyright (c) 2007 Loic Minier <lool at dooz.org>
* Benjamin Larsson
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
/**
* @file
* The 3 alphanumeric copyright notices are md5summed they are from the original
* implementors. The original code is available from http://code.google.com/p/nelly2pcm/
*/
#include "nellymoser.h"
#include "libavutil/lfg.h"
#include "libavutil/random_seed.h"
#include "libavutil/audioconvert.h"
#include "avcodec.h"
#include "dsputil.h"
#include "fft.h"
#include "fmtconvert.h"
#include "sinewin.h"
#define BITSTREAM_READER_LE
#include "get_bits.h"
typedef struct NellyMoserDecodeContext {
AVCodecContext* avctx;
AVFrame frame;
float *float_buf;
AVLFG random_state;
GetBitContext gb;
float scale_bias;
DSPContext dsp;
FFTContext imdct_ctx;
FmtConvertContext fmt_conv;
DECLARE_ALIGNED(32, float, imdct_buf)[2][NELLY_BUF_LEN];
float *imdct_out;
float *imdct_prev;
} NellyMoserDecodeContext;
static void nelly_decode_block(NellyMoserDecodeContext *s,
const unsigned char block[NELLY_BLOCK_LEN],
float audio[NELLY_SAMPLES])
{
int i,j;
float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
float *aptr, *bptr, *pptr, val, pval;
int bits[NELLY_BUF_LEN];
unsigned char v;
init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
bptr = buf;
pptr = pows;
val = ff_nelly_init_table[get_bits(&s->gb, 6)];
for (i=0 ; i<NELLY_BANDS ; i++) {
if (i > 0)
val += ff_nelly_delta_table[get_bits(&s->gb, 5)];
pval = -pow(2, val/2048) * s->scale_bias;
for (j = 0; j < ff_nelly_band_sizes_table[i]; j++) {
*bptr++ = val;
*pptr++ = pval;
}
}
ff_nelly_get_sample_bits(buf, bits);
for (i = 0; i < 2; i++) {
aptr = audio + i * NELLY_BUF_LEN;
init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
skip_bits_long(&s->gb, NELLY_HEADER_BITS + i*NELLY_DETAIL_BITS);
for (j = 0; j < NELLY_FILL_LEN; j++) {
if (bits[j] <= 0) {
aptr[j] = M_SQRT1_2*pows[j];
if (av_lfg_get(&s->random_state) & 1)
aptr[j] *= -1.0;
} else {
v = get_bits(&s->gb, bits[j]);
aptr[j] = ff_nelly_dequantization_table[(1<<bits[j])-1+v]*pows[j];
}
}
memset(&aptr[NELLY_FILL_LEN], 0,
(NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));
s->imdct_ctx.imdct_half(&s->imdct_ctx, s->imdct_out, aptr);
s->dsp.vector_fmul_window(aptr, s->imdct_prev + NELLY_BUF_LEN/2, s->imdct_out, ff_sine_128, NELLY_BUF_LEN/2);
FFSWAP(float *, s->imdct_out, s->imdct_prev);
}
}
static av_cold int decode_init(AVCodecContext * avctx) {
NellyMoserDecodeContext *s = avctx->priv_data;
s->avctx = avctx;
s->imdct_out = s->imdct_buf[0];
s->imdct_prev = s->imdct_buf[1];
av_lfg_init(&s->random_state, 0);
ff_mdct_init(&s->imdct_ctx, 8, 1, 1.0);
ff_dsputil_init(&s->dsp, avctx);
if (avctx->request_sample_fmt == AV_SAMPLE_FMT_FLT) {
s->scale_bias = 1.0/(32768*8);
avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
} else {
s->scale_bias = 1.0/(1*8);
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
ff_fmt_convert_init(&s->fmt_conv, avctx);
s->float_buf = av_mallocz(NELLY_SAMPLES * sizeof(*s->float_buf));
if (!s->float_buf) {
av_log(avctx, AV_LOG_ERROR, "error allocating float buffer\n");
return AVERROR(ENOMEM);
}
}
/* Generate overlap window */
if (!ff_sine_128[127])
ff_init_ff_sine_windows(7);
avctx->channel_layout = AV_CH_LAYOUT_MONO;
avcodec_get_frame_defaults(&s->frame);
avctx->coded_frame = &s->frame;
return 0;
}
static int decode_tag(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
NellyMoserDecodeContext *s = avctx->priv_data;
int blocks, i, ret;
int16_t *samples_s16;
float *samples_flt;
blocks = buf_size / NELLY_BLOCK_LEN;
if (blocks <= 0) {
av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
return AVERROR_INVALIDDATA;
}
if (buf_size % NELLY_BLOCK_LEN) {
av_log(avctx, AV_LOG_WARNING, "Leftover bytes: %d.\n",
buf_size % NELLY_BLOCK_LEN);
}
/* Normal numbers of blocks for sample rates:
* 8000 Hz - 1
* 11025 Hz - 2
* 16000 Hz - 3
* 22050 Hz - 4
* 44100 Hz - 8
*/
/* get output buffer */
s->frame.nb_samples = NELLY_SAMPLES * blocks;
if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
samples_s16 = (int16_t *)s->frame.data[0];
samples_flt = (float *)s->frame.data[0];
for (i=0 ; i<blocks ; i++) {
if (avctx->sample_fmt == AV_SAMPLE_FMT_FLT) {
nelly_decode_block(s, buf, samples_flt);
samples_flt += NELLY_SAMPLES;
} else {
nelly_decode_block(s, buf, s->float_buf);
s->fmt_conv.float_to_int16(samples_s16, s->float_buf, NELLY_SAMPLES);
samples_s16 += NELLY_SAMPLES;
}
buf += NELLY_BLOCK_LEN;
}
*got_frame_ptr = 1;
*(AVFrame *)data = s->frame;
return buf_size;
}
static av_cold int decode_end(AVCodecContext * avctx) {
NellyMoserDecodeContext *s = avctx->priv_data;
av_freep(&s->float_buf);
ff_mdct_end(&s->imdct_ctx);
return 0;
}
AVCodec ff_nellymoser_decoder = {
.name = "nellymoser",
.type = AVMEDIA_TYPE_AUDIO,
.id = CODEC_ID_NELLYMOSER,
.priv_data_size = sizeof(NellyMoserDecodeContext),
.init = decode_init,
.close = decode_end,
.decode = decode_tag,
.capabilities = CODEC_CAP_DR1 | CODEC_CAP_PARAM_CHANGE,
.long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
AV_SAMPLE_FMT_S16,
AV_SAMPLE_FMT_NONE },
};
|
