| /* |
| * 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 "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 = -exp2(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); |
| |
| s->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT); |
| if (!s->fdsp) |
| return AVERROR(ENOMEM); |
| |
| 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); |
| av_freep(&s->fdsp); |
| |
| return 0; |
| } |
| |
| AVCodec ff_nellymoser_decoder = { |
| .name = "nellymoser", |
| .long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"), |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = AV_CODEC_ID_NELLYMOSER, |
| .priv_data_size = sizeof(NellyMoserDecodeContext), |
| .init = decode_init, |
| .close = decode_end, |
| .decode = decode_tag, |
| .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_PARAM_CHANGE, |
| .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT, |
| AV_SAMPLE_FMT_NONE }, |
| }; |