diff options
Diffstat (limited to 'ffmpeg/libavcodec/nellymoserdec.c')
| -rw-r--r-- | ffmpeg/libavcodec/nellymoserdec.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/nellymoserdec.c b/ffmpeg/libavcodec/nellymoserdec.c new file mode 100644 index 0000000..42110a2 --- /dev/null +++ b/ffmpeg/libavcodec/nellymoserdec.c @@ -0,0 +1,209 @@ +/* + * 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 "libavutil/channel_layout.h" +#include "libavutil/float_dsp.h" +#include "libavutil/lfg.h" +#include "libavutil/random_seed.h" +#include "avcodec.h" +#include "fft.h" +#include "fmtconvert.h" +#include "internal.h" +#include "nellymoser.h" +#include "sinewin.h" + +#define BITSTREAM_READER_LE +#include "get_bits.h" + + +typedef struct NellyMoserDecodeContext { + AVCodecContext* avctx; + AVLFG random_state; + GetBitContext gb; + float scale_bias; + AVFloatDSPContext fdsp; + FFTContext imdct_ctx; + 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->fdsp.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); + + avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT); + + s->scale_bias = 1.0/(32768*8); + avctx->sample_fmt = AV_SAMPLE_FMT_FLT; + + /* Generate overlap window */ + if (!ff_sine_128[127]) + ff_init_ff_sine_windows(7); + + avctx->channels = 1; + avctx->channel_layout = AV_CH_LAYOUT_MONO; + + return 0; +} + +static int decode_tag(AVCodecContext *avctx, void *data, + int *got_frame_ptr, AVPacket *avpkt) +{ + AVFrame *frame = data; + const uint8_t *buf = avpkt->data; + const uint8_t *side=av_packet_get_side_data(avpkt, 'F', NULL); + int buf_size = avpkt->size; + NellyMoserDecodeContext *s = avctx->priv_data; + int blocks, i, ret; + 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 + */ + if(side && blocks>1 && avctx->sample_rate%11025==0 && (1<<((side[0]>>2)&3)) == blocks) + avctx->sample_rate= 11025*(blocks/2); + + /* get output buffer */ + frame->nb_samples = NELLY_SAMPLES * blocks; + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + samples_flt = (float *)frame->data[0]; + + for (i=0 ; i<blocks ; i++) { + nelly_decode_block(s, buf, samples_flt); + samples_flt += NELLY_SAMPLES; + buf += NELLY_BLOCK_LEN; + } + + *got_frame_ptr = 1; + + return buf_size; +} + +static av_cold int decode_end(AVCodecContext * avctx) { + NellyMoserDecodeContext *s = avctx->priv_data; + + ff_mdct_end(&s->imdct_ctx); + + return 0; +} + +AVCodec ff_nellymoser_decoder = { + .name = "nellymoser", + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_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_NONE }, +}; |