fram_gen.h - Android社区 - https://www.androidos.net.cn/

/* -----------------------------------------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android

1.    INTRODUCTION
The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
This FDK AAC Codec software is intended to be used on a wide variety of Android devices.

AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
of the MPEG specifications.

Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
individually for the purpose of encoding or decoding bit streams in products that are compliant with
the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
software may already be covered under those patent licenses when it is used for those licensed purposes only.

Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
applications information and documentation.

2.    COPYRIGHT LICENSE

Redistribution and use in source and binary forms, with or without modification, are permitted without
payment of copyright license fees provided that you satisfy the following conditions:

You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
your modifications thereto in source code form.

You must retain the complete text of this software license in the documentation and/or other materials
provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
modifications thereto to recipients of copies in binary form.

The name of Fraunhofer may not be used to endorse or promote products derived from this library without
prior written permission.

You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
software or your modifications thereto.

Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
and the date of any change. For modified versions of the FDK AAC Codec, the term
"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."

3.    NO PATENT LICENSE

NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
respect to this software.

You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
by appropriate patent licenses.

4.    DISCLAIMER

This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
or business interruption, however caused and on any theory of liability, whether in contract, strict
liability, or tort (including negligence), arising in any way out of the use of this software, even if
advised of the possibility of such damage.

5.    CONTACT INFORMATION

Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
91058 Erlangen, Germany

www.iis.fraunhofer.de/amm
amm-info@iis.fraunhofer.de
----------------------------------------------------------------------------------------------------------- */

/*!
  \file
  \brief  Framing generator prototypes and structs  
*/
#ifndef _FRAM_GEN_H
#define _FRAM_GEN_H

#include "sbr_def.h" /* for MAX_ENVELOPES and MAX_NOISE_ENVELOPES in struct FRAME_INFO and CODEC_TYPE */
#include "sbr_encoder.h" /* for FREQ_RES */

#define MAX_ENVELOPES_VARVAR MAX_ENVELOPES /*!< worst case number of envelopes in a VARVAR frame */
#define MAX_ENVELOPES_FIXVAR_VARFIX 4 /*!< worst case number of envelopes in VARFIX and FIXVAR frames */
#define MAX_NUM_REL 3 /*!< maximum number of relative borders in any VAR frame */

/* SBR frame class definitions */
typedef enum {
  FIXFIX = 0, /*!< bs_frame_class: leading and trailing frame borders are fixed */
  FIXVAR,     /*!< bs_frame_class: leading frame border is fixed, trailing frame border is variable */
  VARFIX,     /*!< bs_frame_class: leading frame border is variable, trailing frame border is fixed */
  VARVAR      /*!< bs_frame_class: leading and trailing frame borders are variable */
  ,FIXFIXonly  /*!< bs_frame_class: leading border fixed (0), trailing border fixed (nrTimeSlots) and encased borders are dynamically derived from the tranPos */
}FRAME_CLASS;

/* helper constants */
#define DC      4711        /*!< helper constant: don't care */
#define EMPTY   (-99)       /*!< helper constant: empty */

/* system constants: AAC+SBR, DRM Frame-Length */
#define FRAME_MIDDLE_SLOT_1920  4
#define NUMBER_TIME_SLOTS_1920  15

#define LD_PRETRAN_OFF           3
#define FRAME_MIDDLE_SLOT_512LD  4
#define NUMBER_TIME_SLOTS_512LD  8
#define TRANSIENT_OFFSET_LD      0

/*
system constants: AAC+SBR or aacPRO (hybrid format), Standard Frame-Length, Multi-Rate
---------------------------------------------------------------------------
Number of slots (numberTimeSlots): 16  (NUMBER_TIME_SLOTS_2048)
Detector-offset (frameMiddleSlot):  4
Overlap                          :  3
Buffer-offset                    :  8  (BUFFER_FRAME_START_2048 = 0)

|<------------tranPos---------->|
                |c|d|e|f|0|1|2|3|4|5|6|7|8|9|a|b|c|d|e|f|
        FixFix  |                               |
        FixVar  |                               :<- ->:
        VarFix  :<- ->:                         |
        VarVar  :<- ->:                         :<- ->:
                0 1 2 3 4 5 6 7 8 9 a b c d e f 0 1 2 3
................................................................................

|-|-|-|-|-|-|-|-B-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-B-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|

frame-generator:0                               16              24              32
analysis-buffer:8                               24              32              40
*/
#define FRAME_MIDDLE_SLOT_2048  4
#define NUMBER_TIME_SLOTS_2048  16

/*
system constants: mp3PRO, Multi-Rate & Single-Rate
--------------------------------------------------
Number of slots (numberTimeSlots):  9    (NUMBER_TIME_SLOTS_1152)
Detector-offset (frameMiddleSlot):  4    (FRAME_MIDDLE_SLOT_1152)
Overlap                          :  3
Buffer-offset                    :  4.5  (BUFFER_FRAME_START_1152 = 0)

|<----tranPos---->|
                 |5|6|7|8|0|1|2|3|4|5|6|7|8|
         FixFix  |                 |
         FixVar  |                 :<- ->:
         VarFix  :<- ->:           |
         VarVar  :<- ->:           :<- ->:
                 0 1 2 3 4 5 6 7 8 0 1 2 3
        .............................................

-|-|-|-|-B-|-|-|-|-|-|-|-|-B-|-|-|-|-|-|-|-|-|

frame-generator: 0                 9       13        18
analysis-buffer: 4.5               13.5              22.5
*/
#define FRAME_MIDDLE_SLOT_1152  4
#define NUMBER_TIME_SLOTS_1152  9

/* system constants: Layer2+SBR */
#define FRAME_MIDDLE_SLOT_2304  8
#define NUMBER_TIME_SLOTS_2304  18

/*!
  \struct SBR_GRID
  \brief  sbr_grid() signals to be converted to bitstream elements

The variables hold the signals (e.g. lengths and numbers) in "clear text"
*/

typedef struct
{
  /* system constants */
  INT bufferFrameStart;     /*!< frame generator vs analysis buffer time alignment (currently set to 0, offset added elsewhere) */
  INT numberTimeSlots;      /*!< number of SBR timeslots per frame */

/* will be adjusted for every frame */
  FRAME_CLASS frameClass;   /*!< SBR frame class  */
  INT bs_num_env;           /*!< bs_num_env, number of envelopes for FIXFIX */
  INT bs_abs_bord;          /*!< bs_abs_bord, absolute border for VARFIX and FIXVAR */
  INT n;                    /*!< number of relative borders for VARFIX and FIXVAR   */
  INT p;                    /*!< pointer-to-transient-border  */
  INT bs_rel_bord[MAX_NUM_REL];         /*!< bs_rel_bord, relative borders for all VAR */
  INT v_f[MAX_ENVELOPES_FIXVAR_VARFIX]; /*!< envelope frequency resolutions for FIXVAR and VARFIX  */

INT bs_abs_bord_0;        /*!< bs_abs_bord_0, leading absolute border for VARVAR */
  INT bs_abs_bord_1;        /*!< bs_abs_bord_1, trailing absolute border for VARVAR */
  INT bs_num_rel_0;         /*!< bs_num_rel_0, number of relative borders associated with leading absolute border for VARVAR */
  INT bs_num_rel_1;         /*!< bs_num_rel_1, number of relative borders associated with trailing absolute border for VARVAR */
  INT bs_rel_bord_0[MAX_NUM_REL];       /*!< bs_rel_bord_0, relative borders associated with leading absolute border for VARVAR */
  INT bs_rel_bord_1[MAX_NUM_REL];       /*!< bs_rel_bord_1, relative borders associated with trailing absolute border for VARVAR */
  INT v_fLR[MAX_ENVELOPES_VARVAR];      /*!< envelope frequency resolutions for VARVAR  */

}
SBR_GRID;
typedef SBR_GRID *HANDLE_SBR_GRID;

/*!
  \struct SBR_FRAME_INFO
  \brief  time/frequency grid description for one frame
*/
typedef struct
{
  INT nEnvelopes;                         /*!< number of envelopes */
  INT borders[MAX_ENVELOPES+1];           /*!< envelope borders in SBR timeslots */
  FREQ_RES freqRes[MAX_ENVELOPES];        /*!< frequency resolution of each envelope */
  INT shortEnv;                           /*!< number of an envelope to be shortened (starting at 1) or 0 for no shortened envelope */
  INT nNoiseEnvelopes;                    /*!< number of noise floors */
  INT bordersNoise[MAX_NOISE_ENVELOPES+1];/*!< noise floor borders in SBR timeslots */
}
SBR_FRAME_INFO;
/* WARNING: When rearranging the elements of this struct keep in mind that the static
 * initializations in the corresponding C-file have to be rearranged as well!
 * snd 2002/01/23
 */
typedef SBR_FRAME_INFO *HANDLE_SBR_FRAME_INFO;

/*!
  \struct SBR_ENVELOPE_FRAME
  \brief  frame generator main struct

Contains tuning parameters, time/frequency grid description, sbr_grid() bitstream elements, and generator internal signals
*/
typedef struct
{
  /* system constants */
  INT frameMiddleSlot;      /*!< transient detector offset in SBR timeslots */

/* basic tuning parameters */
  INT staticFraming;           /*!< 1: run static framing in time, i.e. exclusive use of bs_frame_class = FIXFIX */
  INT numEnvStatic;            /*!< number of envelopes per frame for static framing */
  FREQ_RES freq_res_fixfix[2]; /*!< envelope frequency resolution to use for bs_frame_class = FIXFIX; single env and split */
  UCHAR fResTransIsLow;        /*!< frequency resolution for transient frames - always low (0) or according to table (1) */

/* expert tuning parameters */
  const int *v_tuningSegm;  /*!< segment lengths to use around transient */
  const int *v_tuningFreq;  /*!< frequency resolutions to use around transient */
  INT dmin;                 /*!< minimum length of dependent segments */
  INT dmax;                 /*!< maximum length of dependent segments */
  INT allowSpread;          /*!< 1: allow isolated transient to influence grid of 3 consecutive frames */

/* internally used signals */
  FRAME_CLASS frameClassOld;                /*!< frame class used for previous frame */
  INT spreadFlag;                           /*!< 1: use VARVAR instead of VARFIX to follow up old transient */

INT v_bord[2 * MAX_ENVELOPES_VARVAR + 1]; /*!< borders for current frame and preliminary borders for next frame (fixed borders excluded) */
  INT length_v_bord;                        /*!< helper variable: length of v_bord */
  INT v_freq[2 * MAX_ENVELOPES_VARVAR + 1]; /*!< frequency resolutions for current frame and preliminary resolutions for next frame */
  INT length_v_freq;                        /*!< helper variable: length of v_freq */

INT v_bordFollow[MAX_ENVELOPES_VARVAR];   /*!< preliminary borders for current frame (calculated during previous frame) */
  INT length_v_bordFollow;                  /*!< helper variable: length of v_bordFollow */
  INT i_tranFollow;                         /*!< points to transient border in v_bordFollow (may be negative, see keepForFollowUp()) */
  INT i_fillFollow;                         /*!< points to first fill border in v_bordFollow */
  INT v_freqFollow[MAX_ENVELOPES_VARVAR];   /*!< preliminary frequency resolutions for current frame (calculated during previous frame) */
  INT length_v_freqFollow;                  /*!< helper variable: length of v_freqFollow */

/* externally needed signals */
  SBR_GRID         SbrGrid;         /*!< sbr_grid() signals to be converted to bitstream elements */
  SBR_FRAME_INFO   SbrFrameInfo;    /*!< time/frequency grid description for one frame */
}
SBR_ENVELOPE_FRAME;
typedef SBR_ENVELOPE_FRAME *HANDLE_SBR_ENVELOPE_FRAME;

void
FDKsbrEnc_initFrameInfoGenerator (
              HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
              INT       allowSpread,
              INT       numEnvStatic,
              INT       staticFraming,
              INT       timeSlots,
        const FREQ_RES* freq_res_fixfix
             ,UCHAR     fResTransIsLow,
              INT       ldGrid
        );

HANDLE_SBR_FRAME_INFO
FDKsbrEnc_frameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
                    UCHAR *v_transient_info,
                    UCHAR *v_transient_info_pre,
                    int ldGrid,
                    const int *v_tuning);

#endif

C++程序 | 310行 | 14.4 KB

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