390872c89aef4153bc33147f534e7a9fc7172bbf
[libav.git] / libavcodec / nellymoserdec.c
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
34 #include "libavutil/channel_layout.h"
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 "bitstream.h"
42 #include "fft.h"
43 #include "internal.h"
44 #include "nellymoser.h"
45 #include "sinewin.h"
46
47
48 typedef struct NellyMoserDecodeContext {
49 AVCodecContext* avctx;
50 AVLFG random_state;
51 BitstreamContext bc;
52 float scale_bias;
53 AVFloatDSPContext fdsp;
54 FFTContext imdct_ctx;
55 DECLARE_ALIGNED(32, float, imdct_buf)[2][NELLY_BUF_LEN];
56 float *imdct_out;
57 float *imdct_prev;
58 } NellyMoserDecodeContext;
59
60 static void nelly_decode_block(NellyMoserDecodeContext *s,
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
70 bitstream_init(&s->bc, block, NELLY_BLOCK_LEN * 8);
71
72 bptr = buf;
73 pptr = pows;
74 val = ff_nelly_init_table[bitstream_read(&s->bc, 6)];
75 for (i=0 ; i<NELLY_BANDS ; i++) {
76 if (i > 0)
77 val += ff_nelly_delta_table[bitstream_read(&s->bc, 5)];
78 pval = -pow(2, 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
86 ff_nelly_get_sample_bits(buf, bits);
87
88 for (i = 0; i < 2; i++) {
89 aptr = audio + i * NELLY_BUF_LEN;
90
91 bitstream_init(&s->bc, block, NELLY_BLOCK_LEN * 8);
92 bitstream_skip(&s->bc, NELLY_HEADER_BITS + i * NELLY_DETAIL_BITS);
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 = bitstream_read(&s->bc, 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) {
116 NellyMoserDecodeContext *s = avctx->priv_data;
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 avpriv_float_dsp_init(&s->fdsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
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])
131 ff_init_ff_sine_windows(7);
132
133 avctx->channels = 1;
134 avctx->channel_layout = AV_CH_LAYOUT_MONO;
135
136 return 0;
137 }
138
139 static int decode_tag(AVCodecContext *avctx, void *data,
140 int *got_frame_ptr, AVPacket *avpkt)
141 {
142 AVFrame *frame = data;
143 const uint8_t *buf = avpkt->data;
144 int buf_size = avpkt->size;
145 NellyMoserDecodeContext *s = avctx->priv_data;
146 int blocks, i, ret;
147 float *samples_flt;
148
149 blocks = buf_size / NELLY_BLOCK_LEN;
150 if (blocks <= 0) {
151 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
152 return AVERROR_INVALIDDATA;
153 }
154 if (buf_size % NELLY_BLOCK_LEN) {
155 av_log(avctx, AV_LOG_WARNING, "Leftover bytes: %d.\n",
156 buf_size % NELLY_BLOCK_LEN);
157 }
158 /* Normal numbers of blocks for sample rates:
159 * 8000 Hz - 1
160 * 11025 Hz - 2
161 * 16000 Hz - 3
162 * 22050 Hz - 4
163 * 44100 Hz - 8
164 */
165
166 /* get output buffer */
167 frame->nb_samples = NELLY_SAMPLES * blocks;
168 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
169 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
170 return ret;
171 }
172 samples_flt = (float *)frame->data[0];
173
174 for (i=0 ; i<blocks ; i++) {
175 nelly_decode_block(s, buf, samples_flt);
176 samples_flt += NELLY_SAMPLES;
177 buf += NELLY_BLOCK_LEN;
178 }
179
180 *got_frame_ptr = 1;
181
182 return buf_size;
183 }
184
185 static av_cold int decode_end(AVCodecContext * avctx) {
186 NellyMoserDecodeContext *s = avctx->priv_data;
187
188 ff_mdct_end(&s->imdct_ctx);
189
190 return 0;
191 }
192
193 AVCodec ff_nellymoser_decoder = {
194 .name = "nellymoser",
195 .long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
196 .type = AVMEDIA_TYPE_AUDIO,
197 .id = AV_CODEC_ID_NELLYMOSER,
198 .priv_data_size = sizeof(NellyMoserDecodeContext),
199 .init = decode_init,
200 .close = decode_end,
201 .decode = decode_tag,
202 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_PARAM_CHANGE,
203 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
204 AV_SAMPLE_FMT_NONE },
205 };