blob: b0deb79cf5d03b596c57851fdc8afa2f39700655
| 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 "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 { |
| 49 | AVCodecContext* avctx; |
| 50 | AVLFG random_state; |
| 51 | GetBitContext gb; |
| 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 | init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8); |
| 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 | |
| 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 | init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8); |
| 92 | skip_bits_long(&s->gb, 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 = 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) { |
| 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 | s->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT); |
| 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]) |
| 133 | ff_init_ff_sine_windows(7); |
| 134 | |
| 135 | avctx->channels = 1; |
| 136 | avctx->channel_layout = AV_CH_LAYOUT_MONO; |
| 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; |
| 148 | NellyMoserDecodeContext *s = avctx->priv_data; |
| 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) { |
| 191 | NellyMoserDecodeContext *s = avctx->priv_data; |
| 192 | |
| 193 | ff_mdct_end(&s->imdct_ctx); |
| 194 | av_freep(&s->fdsp); |
| 195 | |
| 196 | return 0; |
| 197 | } |
| 198 | |
| 199 | AVCodec ff_nellymoser_decoder = { |
| 200 | .name = "nellymoser", |
| 201 | .long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"), |
| 202 | .type = AVMEDIA_TYPE_AUDIO, |
| 203 | .id = AV_CODEC_ID_NELLYMOSER, |
| 204 | .priv_data_size = sizeof(NellyMoserDecodeContext), |
| 205 | .init = decode_init, |
| 206 | .close = decode_end, |
| 207 | .decode = decode_tag, |
| 208 | .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_PARAM_CHANGE, |
| 209 | .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT, |
| 210 | AV_SAMPLE_FMT_NONE }, |
| 211 | }; |
| 212 |