2 * NellyMoser audio decoder
3 * Copyright (c) 2007 a840bda5870ba11f19698ff6eb9581dfb0f95fa5,
4 * 539459aeb7d425140b62a3ec7dbf6dc8e408a306, and
5 * 520e17cd55896441042b14df2566a6eb610ed444
6 * Copyright (c) 2007 Loic Minier <lool at dooz.org>
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:
16 * The above copyright notice and this permission notice shall be included in
17 * all copies or substantial portions of the Software.
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.
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/
34 #include "libavutil/channel_layout.h"
35 #include "libavutil/float_dsp.h"
36 #include "libavutil/lfg.h"
37 #include "libavutil/random_seed.h"
40 #include "fmtconvert.h"
42 #include "nellymoser.h"
45 #define BITSTREAM_READER_LE
49 typedef struct NellyMoserDecodeContext
{
50 AVCodecContext
* avctx
;
54 AVFloatDSPContext
*fdsp
;
56 DECLARE_ALIGNED(32, float, imdct_buf
)[2][NELLY_BUF_LEN
];
59 } NellyMoserDecodeContext
;
61 static void nelly_decode_block(NellyMoserDecodeContext
*s
,
62 const unsigned char block
[NELLY_BLOCK_LEN
],
63 float audio
[NELLY_SAMPLES
])
66 float buf
[NELLY_FILL_LEN
], pows
[NELLY_FILL_LEN
];
67 float *aptr
, *bptr
, *pptr
, val
, pval
;
68 int bits
[NELLY_BUF_LEN
];
71 init_get_bits(&s
->gb
, block
, NELLY_BLOCK_LEN
* 8);
75 val
= ff_nelly_init_table
[get_bits(&s
->gb
, 6)];
76 for (i
=0 ; i
<NELLY_BANDS
; i
++) {
78 val
+= ff_nelly_delta_table
[get_bits(&s
->gb
, 5)];
79 pval
= -pow(2, val
/2048) * s
->scale_bias
;
80 for (j
= 0; j
< ff_nelly_band_sizes_table
[i
]; j
++) {
87 ff_nelly_get_sample_bits(buf
, bits
);
89 for (i
= 0; i
< 2; i
++) {
90 aptr
= audio
+ i
* NELLY_BUF_LEN
;
92 init_get_bits(&s
->gb
, block
, NELLY_BLOCK_LEN
* 8);
93 skip_bits_long(&s
->gb
, NELLY_HEADER_BITS
+ i
*NELLY_DETAIL_BITS
);
95 for (j
= 0; j
< NELLY_FILL_LEN
; j
++) {
97 aptr
[j
] = M_SQRT1_2
*pows
[j
];
98 if (av_lfg_get(&s
->random_state
) & 1)
101 v
= get_bits(&s
->gb
, bits
[j
]);
102 aptr
[j
] = ff_nelly_dequantization_table
[(1<<bits
[j
])-1+v
]*pows
[j
];
105 memset(&aptr
[NELLY_FILL_LEN
], 0,
106 (NELLY_BUF_LEN
- NELLY_FILL_LEN
) * sizeof(float));
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
,
112 FFSWAP(float *, s
->imdct_out
, s
->imdct_prev
);
116 static av_cold
int decode_init(AVCodecContext
* avctx
) {
117 NellyMoserDecodeContext
*s
= avctx
->priv_data
;
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);
125 s
->fdsp
= avpriv_float_dsp_alloc(avctx
->flags
& CODEC_FLAG_BITEXACT
);
127 return AVERROR(ENOMEM
);
129 s
->scale_bias
= 1.0/(32768*8);
130 avctx
->sample_fmt
= AV_SAMPLE_FMT_FLT
;
132 /* Generate overlap window */
133 if (!ff_sine_128
[127])
134 ff_init_ff_sine_windows(7);
137 avctx
->channel_layout
= AV_CH_LAYOUT_MONO
;
142 static int decode_tag(AVCodecContext
*avctx
, void *data
,
143 int *got_frame_ptr
, AVPacket
*avpkt
)
145 AVFrame
*frame
= data
;
146 const uint8_t *buf
= avpkt
->data
;
147 const uint8_t *side
=av_packet_get_side_data(avpkt
, 'F', NULL
);
148 int buf_size
= avpkt
->size
;
149 NellyMoserDecodeContext
*s
= avctx
->priv_data
;
153 blocks
= buf_size
/ NELLY_BLOCK_LEN
;
156 av_log(avctx
, AV_LOG_ERROR
, "Packet is too small\n");
157 return AVERROR_INVALIDDATA
;
160 if (buf_size
% NELLY_BLOCK_LEN
) {
161 av_log(avctx
, AV_LOG_WARNING
, "Leftover bytes: %d.\n",
162 buf_size
% NELLY_BLOCK_LEN
);
164 /* Normal numbers of blocks for sample rates:
171 if(side
&& blocks
>1 && avctx
->sample_rate
%11025==0 && (1<<((side
[0]>>2)&3)) == blocks
)
172 avctx
->sample_rate
= 11025*(blocks
/2);
174 /* get output buffer */
175 frame
->nb_samples
= NELLY_SAMPLES
* blocks
;
176 if ((ret
= ff_get_buffer(avctx
, frame
, 0)) < 0)
178 samples_flt
= (float *)frame
->data
[0];
180 for (i
=0 ; i
<blocks
; i
++) {
181 nelly_decode_block(s
, buf
, samples_flt
);
182 samples_flt
+= NELLY_SAMPLES
;
183 buf
+= NELLY_BLOCK_LEN
;
191 static av_cold
int decode_end(AVCodecContext
* avctx
) {
192 NellyMoserDecodeContext
*s
= avctx
->priv_data
;
194 ff_mdct_end(&s
->imdct_ctx
);
200 AVCodec ff_nellymoser_decoder
= {
201 .name
= "nellymoser",
202 .long_name
= NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
203 .type
= AVMEDIA_TYPE_AUDIO
,
204 .id
= AV_CODEC_ID_NELLYMOSER
,
205 .priv_data_size
= sizeof(NellyMoserDecodeContext
),
208 .decode
= decode_tag
,
209 .capabilities
= CODEC_CAP_DR1
| CODEC_CAP_PARAM_CHANGE
,
210 .sample_fmts
= (const enum AVSampleFormat
[]) { AV_SAMPLE_FMT_FLT
,
211 AV_SAMPLE_FMT_NONE
},