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			595 lines
		
	
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			595 lines
		
	
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * AAC decoder
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 * Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org )
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 * Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com )
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 * Copyright (c) 2008-2013 Alex Converse <alex.converse@gmail.com>
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 *
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 * AAC LATM decoder
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 * Copyright (c) 2008-2010 Paul Kendall <paul@kcbbs.gen.nz>
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 * Copyright (c) 2010      Janne Grunau <janne-libav@jannau.net>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
 | 
						|
 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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						|
 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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						|
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | 
						|
 * Lesser General Public License for more details.
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						|
 *
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 * You should have received a copy of the GNU Lesser General Public
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						|
 * License along with FFmpeg; if not, write to the Free Software
 | 
						|
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * AAC decoder
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 * @author Oded Shimon  ( ods15 ods15 dyndns org )
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 * @author Maxim Gavrilov ( maxim.gavrilov gmail com )
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 */
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#define FFT_FLOAT 1
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#define FFT_FIXED_32 0
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#define USE_FIXED 0
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#include "libavutil/float_dsp.h"
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#include "libavutil/opt.h"
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#include "avcodec.h"
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#include "internal.h"
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#include "get_bits.h"
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#include "fft.h"
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#include "mdct15.h"
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#include "lpc.h"
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#include "kbdwin.h"
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#include "sinewin.h"
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#include "aac.h"
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#include "aactab.h"
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#include "aacdectab.h"
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#include "adts_header.h"
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#include "cbrt_data.h"
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#include "sbr.h"
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#include "aacsbr.h"
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#include "mpeg4audio.h"
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#include "profiles.h"
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#include "libavutil/intfloat.h"
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#include <errno.h>
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#include <math.h>
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#include <stdint.h>
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#include <string.h>
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#if ARCH_ARM
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#   include "arm/aac.h"
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#elif ARCH_MIPS
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#   include "mips/aacdec_mips.h"
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#endif
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static av_always_inline void reset_predict_state(PredictorState *ps)
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{
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    ps->r0   = 0.0f;
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    ps->r1   = 0.0f;
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    ps->cor0 = 0.0f;
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    ps->cor1 = 0.0f;
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    ps->var0 = 1.0f;
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    ps->var1 = 1.0f;
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}
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#ifndef VMUL2
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static inline float *VMUL2(float *dst, const float *v, unsigned idx,
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						|
                           const float *scale)
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{
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						|
    float s = *scale;
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    *dst++ = v[idx    & 15] * s;
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    *dst++ = v[idx>>4 & 15] * s;
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    return dst;
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}
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#endif
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#ifndef VMUL4
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static inline float *VMUL4(float *dst, const float *v, unsigned idx,
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                           const float *scale)
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{
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    float s = *scale;
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    *dst++ = v[idx    & 3] * s;
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    *dst++ = v[idx>>2 & 3] * s;
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    *dst++ = v[idx>>4 & 3] * s;
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    *dst++ = v[idx>>6 & 3] * s;
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    return dst;
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}
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#endif
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#ifndef VMUL2S
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static inline float *VMUL2S(float *dst, const float *v, unsigned idx,
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                            unsigned sign, const float *scale)
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{
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    union av_intfloat32 s0, s1;
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    s0.f = s1.f = *scale;
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    s0.i ^= sign >> 1 << 31;
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    s1.i ^= sign      << 31;
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    *dst++ = v[idx    & 15] * s0.f;
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    *dst++ = v[idx>>4 & 15] * s1.f;
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    return dst;
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}
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#endif
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#ifndef VMUL4S
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static inline float *VMUL4S(float *dst, const float *v, unsigned idx,
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                            unsigned sign, const float *scale)
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{
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    unsigned nz = idx >> 12;
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    union av_intfloat32 s = { .f = *scale };
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    union av_intfloat32 t;
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    t.i = s.i ^ (sign & 1U<<31);
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    *dst++ = v[idx    & 3] * t.f;
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    sign <<= nz & 1; nz >>= 1;
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    t.i = s.i ^ (sign & 1U<<31);
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    *dst++ = v[idx>>2 & 3] * t.f;
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    sign <<= nz & 1; nz >>= 1;
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    t.i = s.i ^ (sign & 1U<<31);
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    *dst++ = v[idx>>4 & 3] * t.f;
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    sign <<= nz & 1;
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    t.i = s.i ^ (sign & 1U<<31);
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    *dst++ = v[idx>>6 & 3] * t.f;
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    return dst;
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}
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#endif
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static av_always_inline float flt16_round(float pf)
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{
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    union av_intfloat32 tmp;
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    tmp.f = pf;
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						|
    tmp.i = (tmp.i + 0x00008000U) & 0xFFFF0000U;
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    return tmp.f;
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}
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static av_always_inline float flt16_even(float pf)
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{
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    union av_intfloat32 tmp;
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    tmp.f = pf;
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    tmp.i = (tmp.i + 0x00007FFFU + (tmp.i & 0x00010000U >> 16)) & 0xFFFF0000U;
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    return tmp.f;
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}
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static av_always_inline float flt16_trunc(float pf)
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{
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    union av_intfloat32 pun;
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    pun.f = pf;
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    pun.i &= 0xFFFF0000U;
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    return pun.f;
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}
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static av_always_inline void predict(PredictorState *ps, float *coef,
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                                     int output_enable)
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{
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    const float a     = 0.953125; // 61.0 / 64
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    const float alpha = 0.90625;  // 29.0 / 32
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    float e0, e1;
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    float pv;
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    float k1, k2;
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    float   r0 = ps->r0,     r1 = ps->r1;
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    float cor0 = ps->cor0, cor1 = ps->cor1;
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    float var0 = ps->var0, var1 = ps->var1;
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    k1 = var0 > 1 ? cor0 * flt16_even(a / var0) : 0;
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    k2 = var1 > 1 ? cor1 * flt16_even(a / var1) : 0;
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    pv = flt16_round(k1 * r0 + k2 * r1);
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    if (output_enable)
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        *coef += pv;
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    e0 = *coef;
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    e1 = e0 - k1 * r0;
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    ps->cor1 = flt16_trunc(alpha * cor1 + r1 * e1);
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    ps->var1 = flt16_trunc(alpha * var1 + 0.5f * (r1 * r1 + e1 * e1));
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    ps->cor0 = flt16_trunc(alpha * cor0 + r0 * e0);
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    ps->var0 = flt16_trunc(alpha * var0 + 0.5f * (r0 * r0 + e0 * e0));
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    ps->r1 = flt16_trunc(a * (r0 - k1 * e0));
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    ps->r0 = flt16_trunc(a * e0);
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}
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/**
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 * Apply dependent channel coupling (applied before IMDCT).
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 *
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 * @param   index   index into coupling gain array
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 */
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static void apply_dependent_coupling(AACContext *ac,
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                                     SingleChannelElement *target,
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                                     ChannelElement *cce, int index)
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{
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    IndividualChannelStream *ics = &cce->ch[0].ics;
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						|
    const uint16_t *offsets = ics->swb_offset;
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    float *dest = target->coeffs;
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    const float *src = cce->ch[0].coeffs;
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						|
    int g, i, group, k, idx = 0;
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    if (ac->oc[1].m4ac.object_type == AOT_AAC_LTP) {
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        av_log(ac->avctx, AV_LOG_ERROR,
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               "Dependent coupling is not supported together with LTP\n");
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        return;
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    }
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    for (g = 0; g < ics->num_window_groups; g++) {
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        for (i = 0; i < ics->max_sfb; i++, idx++) {
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            if (cce->ch[0].band_type[idx] != ZERO_BT) {
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                const float gain = cce->coup.gain[index][idx];
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                for (group = 0; group < ics->group_len[g]; group++) {
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                    for (k = offsets[i]; k < offsets[i + 1]; k++) {
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                        // FIXME: SIMDify
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                        dest[group * 128 + k] += gain * src[group * 128 + k];
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                    }
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                }
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            }
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        }
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        dest += ics->group_len[g] * 128;
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        src  += ics->group_len[g] * 128;
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    }
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}
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/**
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 * Apply independent channel coupling (applied after IMDCT).
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 *
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 * @param   index   index into coupling gain array
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 */
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static void apply_independent_coupling(AACContext *ac,
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                                       SingleChannelElement *target,
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                                       ChannelElement *cce, int index)
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{
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    int i;
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    const float gain = cce->coup.gain[index][0];
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    const float *src = cce->ch[0].ret;
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    float *dest = target->ret;
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    const int len = 1024 << (ac->oc[1].m4ac.sbr == 1);
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    for (i = 0; i < len; i++)
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        dest[i] += gain * src[i];
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}
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#include "aacdec_template.c"
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#define LOAS_SYNC_WORD   0x2b7       ///< 11 bits LOAS sync word
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struct LATMContext {
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    AACContext aac_ctx;     ///< containing AACContext
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    int initialized;        ///< initialized after a valid extradata was seen
 | 
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    // parser data
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    int audio_mux_version_A; ///< LATM syntax version
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    int frame_length_type;   ///< 0/1 variable/fixed frame length
 | 
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    int frame_length;        ///< frame length for fixed frame length
 | 
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};
 | 
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 | 
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static inline uint32_t latm_get_value(GetBitContext *b)
 | 
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{
 | 
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    int length = get_bits(b, 2);
 | 
						|
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    return get_bits_long(b, (length+1)*8);
 | 
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}
 | 
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 | 
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static int latm_decode_audio_specific_config(struct LATMContext *latmctx,
 | 
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                                             GetBitContext *gb, int asclen)
 | 
						|
{
 | 
						|
    AACContext *ac        = &latmctx->aac_ctx;
 | 
						|
    AVCodecContext *avctx = ac->avctx;
 | 
						|
    MPEG4AudioConfig m4ac = { 0 };
 | 
						|
    GetBitContext gbc;
 | 
						|
    int config_start_bit  = get_bits_count(gb);
 | 
						|
    int sync_extension    = 0;
 | 
						|
    int bits_consumed, esize, i;
 | 
						|
 | 
						|
    if (asclen > 0) {
 | 
						|
        sync_extension = 1;
 | 
						|
        asclen         = FFMIN(asclen, get_bits_left(gb));
 | 
						|
        init_get_bits(&gbc, gb->buffer, config_start_bit + asclen);
 | 
						|
        skip_bits_long(&gbc, config_start_bit);
 | 
						|
    } else if (asclen == 0) {
 | 
						|
        gbc = *gb;
 | 
						|
    } else {
 | 
						|
        return AVERROR_INVALIDDATA;
 | 
						|
    }
 | 
						|
 | 
						|
    if (get_bits_left(gb) <= 0)
 | 
						|
        return AVERROR_INVALIDDATA;
 | 
						|
 | 
						|
    bits_consumed = decode_audio_specific_config_gb(NULL, avctx, &m4ac,
 | 
						|
                                                    &gbc, config_start_bit,
 | 
						|
                                                    sync_extension);
 | 
						|
 | 
						|
    if (bits_consumed < config_start_bit)
 | 
						|
        return AVERROR_INVALIDDATA;
 | 
						|
    bits_consumed -= config_start_bit;
 | 
						|
 | 
						|
    if (asclen == 0)
 | 
						|
      asclen = bits_consumed;
 | 
						|
 | 
						|
    if (!latmctx->initialized ||
 | 
						|
        ac->oc[1].m4ac.sample_rate != m4ac.sample_rate ||
 | 
						|
        ac->oc[1].m4ac.chan_config != m4ac.chan_config) {
 | 
						|
 | 
						|
        if (latmctx->initialized) {
 | 
						|
            av_log(avctx, AV_LOG_INFO, "audio config changed (sample_rate=%d, chan_config=%d)\n", m4ac.sample_rate, m4ac.chan_config);
 | 
						|
        } else {
 | 
						|
            av_log(avctx, AV_LOG_DEBUG, "initializing latmctx\n");
 | 
						|
        }
 | 
						|
        latmctx->initialized = 0;
 | 
						|
 | 
						|
        esize = (asclen + 7) / 8;
 | 
						|
 | 
						|
        if (avctx->extradata_size < esize) {
 | 
						|
            av_free(avctx->extradata);
 | 
						|
            avctx->extradata = av_malloc(esize + AV_INPUT_BUFFER_PADDING_SIZE);
 | 
						|
            if (!avctx->extradata)
 | 
						|
                return AVERROR(ENOMEM);
 | 
						|
        }
 | 
						|
 | 
						|
        avctx->extradata_size = esize;
 | 
						|
        gbc = *gb;
 | 
						|
        for (i = 0; i < esize; i++) {
 | 
						|
          avctx->extradata[i] = get_bits(&gbc, 8);
 | 
						|
        }
 | 
						|
        memset(avctx->extradata+esize, 0, AV_INPUT_BUFFER_PADDING_SIZE);
 | 
						|
    }
 | 
						|
    skip_bits_long(gb, asclen);
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static int read_stream_mux_config(struct LATMContext *latmctx,
 | 
						|
                                  GetBitContext *gb)
 | 
						|
{
 | 
						|
    int ret, audio_mux_version = get_bits(gb, 1);
 | 
						|
 | 
						|
    latmctx->audio_mux_version_A = 0;
 | 
						|
    if (audio_mux_version)
 | 
						|
        latmctx->audio_mux_version_A = get_bits(gb, 1);
 | 
						|
 | 
						|
    if (!latmctx->audio_mux_version_A) {
 | 
						|
 | 
						|
        if (audio_mux_version)
 | 
						|
            latm_get_value(gb);                 // taraFullness
 | 
						|
 | 
						|
        skip_bits(gb, 1);                       // allStreamSameTimeFraming
 | 
						|
        skip_bits(gb, 6);                       // numSubFrames
 | 
						|
        // numPrograms
 | 
						|
        if (get_bits(gb, 4)) {                  // numPrograms
 | 
						|
            avpriv_request_sample(latmctx->aac_ctx.avctx, "Multiple programs");
 | 
						|
            return AVERROR_PATCHWELCOME;
 | 
						|
        }
 | 
						|
 | 
						|
        // for each program (which there is only one in DVB)
 | 
						|
 | 
						|
        // for each layer (which there is only one in DVB)
 | 
						|
        if (get_bits(gb, 3)) {                   // numLayer
 | 
						|
            avpriv_request_sample(latmctx->aac_ctx.avctx, "Multiple layers");
 | 
						|
            return AVERROR_PATCHWELCOME;
 | 
						|
        }
 | 
						|
 | 
						|
        // for all but first stream: use_same_config = get_bits(gb, 1);
 | 
						|
        if (!audio_mux_version) {
 | 
						|
            if ((ret = latm_decode_audio_specific_config(latmctx, gb, 0)) < 0)
 | 
						|
                return ret;
 | 
						|
        } else {
 | 
						|
            int ascLen = latm_get_value(gb);
 | 
						|
            if ((ret = latm_decode_audio_specific_config(latmctx, gb, ascLen)) < 0)
 | 
						|
                return ret;
 | 
						|
        }
 | 
						|
 | 
						|
        latmctx->frame_length_type = get_bits(gb, 3);
 | 
						|
        switch (latmctx->frame_length_type) {
 | 
						|
        case 0:
 | 
						|
            skip_bits(gb, 8);       // latmBufferFullness
 | 
						|
            break;
 | 
						|
        case 1:
 | 
						|
            latmctx->frame_length = get_bits(gb, 9);
 | 
						|
            break;
 | 
						|
        case 3:
 | 
						|
        case 4:
 | 
						|
        case 5:
 | 
						|
            skip_bits(gb, 6);       // CELP frame length table index
 | 
						|
            break;
 | 
						|
        case 6:
 | 
						|
        case 7:
 | 
						|
            skip_bits(gb, 1);       // HVXC frame length table index
 | 
						|
            break;
 | 
						|
        }
 | 
						|
 | 
						|
        if (get_bits(gb, 1)) {                  // other data
 | 
						|
            if (audio_mux_version) {
 | 
						|
                latm_get_value(gb);             // other_data_bits
 | 
						|
            } else {
 | 
						|
                int esc;
 | 
						|
                do {
 | 
						|
                    if (get_bits_left(gb) < 9)
 | 
						|
                        return AVERROR_INVALIDDATA;
 | 
						|
                    esc = get_bits(gb, 1);
 | 
						|
                    skip_bits(gb, 8);
 | 
						|
                } while (esc);
 | 
						|
            }
 | 
						|
        }
 | 
						|
 | 
						|
        if (get_bits(gb, 1))                     // crc present
 | 
						|
            skip_bits(gb, 8);                    // config_crc
 | 
						|
    }
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static int read_payload_length_info(struct LATMContext *ctx, GetBitContext *gb)
 | 
						|
{
 | 
						|
    uint8_t tmp;
 | 
						|
 | 
						|
    if (ctx->frame_length_type == 0) {
 | 
						|
        int mux_slot_length = 0;
 | 
						|
        do {
 | 
						|
            if (get_bits_left(gb) < 8)
 | 
						|
                return AVERROR_INVALIDDATA;
 | 
						|
            tmp = get_bits(gb, 8);
 | 
						|
            mux_slot_length += tmp;
 | 
						|
        } while (tmp == 255);
 | 
						|
        return mux_slot_length;
 | 
						|
    } else if (ctx->frame_length_type == 1) {
 | 
						|
        return ctx->frame_length;
 | 
						|
    } else if (ctx->frame_length_type == 3 ||
 | 
						|
               ctx->frame_length_type == 5 ||
 | 
						|
               ctx->frame_length_type == 7) {
 | 
						|
        skip_bits(gb, 2);          // mux_slot_length_coded
 | 
						|
    }
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static int read_audio_mux_element(struct LATMContext *latmctx,
 | 
						|
                                  GetBitContext *gb)
 | 
						|
{
 | 
						|
    int err;
 | 
						|
    uint8_t use_same_mux = get_bits(gb, 1);
 | 
						|
    if (!use_same_mux) {
 | 
						|
        if ((err = read_stream_mux_config(latmctx, gb)) < 0)
 | 
						|
            return err;
 | 
						|
    } else if (!latmctx->aac_ctx.avctx->extradata) {
 | 
						|
        av_log(latmctx->aac_ctx.avctx, AV_LOG_DEBUG,
 | 
						|
               "no decoder config found\n");
 | 
						|
        return 1;
 | 
						|
    }
 | 
						|
    if (latmctx->audio_mux_version_A == 0) {
 | 
						|
        int mux_slot_length_bytes = read_payload_length_info(latmctx, gb);
 | 
						|
        if (mux_slot_length_bytes < 0 || mux_slot_length_bytes * 8LL > get_bits_left(gb)) {
 | 
						|
            av_log(latmctx->aac_ctx.avctx, AV_LOG_ERROR, "incomplete frame\n");
 | 
						|
            return AVERROR_INVALIDDATA;
 | 
						|
        } else if (mux_slot_length_bytes * 8 + 256 < get_bits_left(gb)) {
 | 
						|
            av_log(latmctx->aac_ctx.avctx, AV_LOG_ERROR,
 | 
						|
                   "frame length mismatch %d << %d\n",
 | 
						|
                   mux_slot_length_bytes * 8, get_bits_left(gb));
 | 
						|
            return AVERROR_INVALIDDATA;
 | 
						|
        }
 | 
						|
    }
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int latm_decode_frame(AVCodecContext *avctx, void *out,
 | 
						|
                             int *got_frame_ptr, AVPacket *avpkt)
 | 
						|
{
 | 
						|
    struct LATMContext *latmctx = avctx->priv_data;
 | 
						|
    int                 muxlength, err;
 | 
						|
    GetBitContext       gb;
 | 
						|
 | 
						|
    if ((err = init_get_bits8(&gb, avpkt->data, avpkt->size)) < 0)
 | 
						|
        return err;
 | 
						|
 | 
						|
    // check for LOAS sync word
 | 
						|
    if (get_bits(&gb, 11) != LOAS_SYNC_WORD)
 | 
						|
        return AVERROR_INVALIDDATA;
 | 
						|
 | 
						|
    muxlength = get_bits(&gb, 13) + 3;
 | 
						|
    // not enough data, the parser should have sorted this out
 | 
						|
    if (muxlength > avpkt->size)
 | 
						|
        return AVERROR_INVALIDDATA;
 | 
						|
 | 
						|
    if ((err = read_audio_mux_element(latmctx, &gb)))
 | 
						|
        return (err < 0) ? err : avpkt->size;
 | 
						|
 | 
						|
    if (!latmctx->initialized) {
 | 
						|
        if (!avctx->extradata) {
 | 
						|
            *got_frame_ptr = 0;
 | 
						|
            return avpkt->size;
 | 
						|
        } else {
 | 
						|
            push_output_configuration(&latmctx->aac_ctx);
 | 
						|
            if ((err = decode_audio_specific_config(
 | 
						|
                    &latmctx->aac_ctx, avctx, &latmctx->aac_ctx.oc[1].m4ac,
 | 
						|
                    avctx->extradata, avctx->extradata_size*8LL, 1)) < 0) {
 | 
						|
                pop_output_configuration(&latmctx->aac_ctx);
 | 
						|
                return err;
 | 
						|
            }
 | 
						|
            latmctx->initialized = 1;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    if (show_bits(&gb, 12) == 0xfff) {
 | 
						|
        av_log(latmctx->aac_ctx.avctx, AV_LOG_ERROR,
 | 
						|
               "ADTS header detected, probably as result of configuration "
 | 
						|
               "misparsing\n");
 | 
						|
        return AVERROR_INVALIDDATA;
 | 
						|
    }
 | 
						|
 | 
						|
    switch (latmctx->aac_ctx.oc[1].m4ac.object_type) {
 | 
						|
    case AOT_ER_AAC_LC:
 | 
						|
    case AOT_ER_AAC_LTP:
 | 
						|
    case AOT_ER_AAC_LD:
 | 
						|
    case AOT_ER_AAC_ELD:
 | 
						|
        err = aac_decode_er_frame(avctx, out, got_frame_ptr, &gb);
 | 
						|
        break;
 | 
						|
    default:
 | 
						|
        err = aac_decode_frame_int(avctx, out, got_frame_ptr, &gb, avpkt);
 | 
						|
    }
 | 
						|
    if (err < 0)
 | 
						|
        return err;
 | 
						|
 | 
						|
    return muxlength;
 | 
						|
}
 | 
						|
 | 
						|
static av_cold int latm_decode_init(AVCodecContext *avctx)
 | 
						|
{
 | 
						|
    struct LATMContext *latmctx = avctx->priv_data;
 | 
						|
    int ret = aac_decode_init(avctx);
 | 
						|
 | 
						|
    if (avctx->extradata_size > 0)
 | 
						|
        latmctx->initialized = !ret;
 | 
						|
 | 
						|
    return ret;
 | 
						|
}
 | 
						|
 | 
						|
AVCodec ff_aac_decoder = {
 | 
						|
    .name            = "aac",
 | 
						|
    .long_name       = NULL_IF_CONFIG_SMALL("AAC (Advanced Audio Coding)"),
 | 
						|
    .type            = AVMEDIA_TYPE_AUDIO,
 | 
						|
    .id              = AV_CODEC_ID_AAC,
 | 
						|
    .priv_data_size  = sizeof(AACContext),
 | 
						|
    .init            = aac_decode_init,
 | 
						|
    .close           = aac_decode_close,
 | 
						|
    .decode          = aac_decode_frame,
 | 
						|
    .sample_fmts     = (const enum AVSampleFormat[]) {
 | 
						|
        AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE
 | 
						|
    },
 | 
						|
    .capabilities    = AV_CODEC_CAP_CHANNEL_CONF | AV_CODEC_CAP_DR1,
 | 
						|
    .caps_internal   = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
 | 
						|
    .channel_layouts = aac_channel_layout,
 | 
						|
    .flush = flush,
 | 
						|
    .priv_class      = &aac_decoder_class,
 | 
						|
    .profiles        = NULL_IF_CONFIG_SMALL(ff_aac_profiles),
 | 
						|
};
 | 
						|
 | 
						|
/*
 | 
						|
    Note: This decoder filter is intended to decode LATM streams transferred
 | 
						|
    in MPEG transport streams which only contain one program.
 | 
						|
    To do a more complex LATM demuxing a separate LATM demuxer should be used.
 | 
						|
*/
 | 
						|
AVCodec ff_aac_latm_decoder = {
 | 
						|
    .name            = "aac_latm",
 | 
						|
    .long_name       = NULL_IF_CONFIG_SMALL("AAC LATM (Advanced Audio Coding LATM syntax)"),
 | 
						|
    .type            = AVMEDIA_TYPE_AUDIO,
 | 
						|
    .id              = AV_CODEC_ID_AAC_LATM,
 | 
						|
    .priv_data_size  = sizeof(struct LATMContext),
 | 
						|
    .init            = latm_decode_init,
 | 
						|
    .close           = aac_decode_close,
 | 
						|
    .decode          = latm_decode_frame,
 | 
						|
    .sample_fmts     = (const enum AVSampleFormat[]) {
 | 
						|
        AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE
 | 
						|
    },
 | 
						|
    .capabilities    = AV_CODEC_CAP_CHANNEL_CONF | AV_CODEC_CAP_DR1,
 | 
						|
    .caps_internal   = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
 | 
						|
    .channel_layouts = aac_channel_layout,
 | 
						|
    .flush = flush,
 | 
						|
    .profiles        = NULL_IF_CONFIG_SMALL(ff_aac_profiles),
 | 
						|
};
 |