libavcodec/nellymoserdec.c - manifest_repos/ffmpeg - Git at Google

 /*
  * 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"

 #define BITSTREAM_READER_LE
 #include "avcodec.h"
 #include "fft.h"
 #include "get_bits.h"
 #include "internal.h"
 #include "nellymoser.h"
 #include "sinewin.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;

     avctx->channels       = 1;
     avctx->channel_layout = AV_CH_LAYOUT_MONO;

     /* Generate overlap window */
     ff_init_ff_sine_windows(7);

     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;
     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);
     }

     /* 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 | AV_CODEC_CAP_CHANNEL_CONF,
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
                                                       AV_SAMPLE_FMT_NONE },
     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
	/*
	* 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"

	#define BITSTREAM_READER_LE
	#include "avcodec.h"
	#include "fft.h"
	#include "get_bits.h"
	#include "internal.h"
	#include "nellymoser.h"
	#include "sinewin.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;

	avctx->channels = 1;
	avctx->channel_layout = AV_CH_LAYOUT_MONO;

	/* Generate overlap window */
	ff_init_ff_sine_windows(7);

	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;
	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);
	}

	/* 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 \| AV_CODEC_CAP_CHANNEL_CONF,
	.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
	AV_SAMPLE_FMT_NONE },
	.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
	};