FFmpeg
Data Structures | Macros | Functions | Variables
imc.c File Reference

IMC - Intel Music Coder A mdct based codec using a 256 points large transform divided into 32 bands with some mix of scale factors. More...

#include <math.h>
#include <stddef.h>
#include <stdio.h>
#include "libavutil/channel_layout.h"
#include "libavutil/ffmath.h"
#include "libavutil/float_dsp.h"
#include "libavutil/internal.h"
#include "avcodec.h"
#include "bswapdsp.h"
#include "get_bits.h"
#include "fft.h"
#include "internal.h"
#include "sinewin.h"
#include "imcdata.h"

Go to the source code of this file.

Data Structures

struct  IMCChannel
 
struct  IMCContext
 

Macros

#define IMC_BLOCK_SIZE   64
 
#define IMC_FRAME_ID   0x21
 
#define BANDS   32
 
#define COEFFS   256
 
#define VLC_TABLES_SIZE   9512
 

Functions

static double freq2bark (double freq)
 
static av_cold void iac_generate_tabs (IMCContext *q, int sampling_rate)
 
static av_cold int imc_decode_init (AVCodecContext *avctx)
 
static void imc_calculate_coeffs (IMCContext *q, float *flcoeffs1, float *flcoeffs2, int *bandWidthT, float *flcoeffs3, float *flcoeffs5)
 
static void imc_read_level_coeffs (IMCContext *q, int stream_format_code, int *levlCoeffs)
 
static void imc_read_level_coeffs_raw (IMCContext *q, int stream_format_code, int *levlCoeffs)
 
static void imc_decode_level_coefficients (IMCContext *q, int *levlCoeffBuf, float *flcoeffs1, float *flcoeffs2)
 
static void imc_decode_level_coefficients2 (IMCContext *q, int *levlCoeffBuf, float *old_floor, float *flcoeffs1, float *flcoeffs2)
 
static void imc_decode_level_coefficients_raw (IMCContext *q, int *levlCoeffBuf, float *flcoeffs1, float *flcoeffs2)
 
static int bit_allocation (IMCContext *q, IMCChannel *chctx, int stream_format_code, int freebits, int flag)
 Perform bit allocation depending on bits available. More...
 
static void imc_get_skip_coeff (IMCContext *q, IMCChannel *chctx)
 
static void imc_adjust_bit_allocation (IMCContext *q, IMCChannel *chctx, int summer)
 Increase highest' band coefficient sizes as some bits won't be used. More...
 
static void imc_imdct256 (IMCContext *q, IMCChannel *chctx, int channels)
 
static int inverse_quant_coeff (IMCContext *q, IMCChannel *chctx, int stream_format_code)
 
static void imc_get_coeffs (AVCodecContext *avctx, IMCContext *q, IMCChannel *chctx)
 
static void imc_refine_bit_allocation (IMCContext *q, IMCChannel *chctx)
 
static int imc_decode_block (AVCodecContext *avctx, IMCContext *q, int ch)
 
static int imc_decode_frame (AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
 
static av_cold int imc_decode_close (AVCodecContext *avctx)
 
static av_cold void flush (AVCodecContext *avctx)
 

Variables

static VLC huffman_vlc [4][4]
 
static const int vlc_offsets [17]
 
static VLC_TYPE vlc_tables [VLC_TABLES_SIZE][2]
 

Detailed Description

IMC - Intel Music Coder A mdct based codec using a 256 points large transform divided into 32 bands with some mix of scale factors.

Only mono is supported.

Definition in file imc.c.

Macro Definition Documentation

#define IMC_BLOCK_SIZE   64

Definition at line 50 of file imc.c.

Referenced by imc_decode_frame().

#define IMC_FRAME_ID   0x21

Definition at line 51 of file imc.c.

#define BANDS   32
#define COEFFS   256

Definition at line 53 of file imc.c.

Referenced by imc_decode_block(), imc_decode_frame(), imc_decode_init(), and imc_imdct256().

#define VLC_TABLES_SIZE   9512

Definition at line 113 of file imc.c.

Function Documentation

static double freq2bark ( double  freq)
inlinestatic

Definition at line 122 of file imc.c.

Referenced by iac_generate_tabs().

static av_cold void iac_generate_tabs ( IMCContext q,
int  sampling_rate 
)
static

Definition at line 127 of file imc.c.

Referenced by imc_decode_init().

static av_cold int imc_decode_init ( AVCodecContext avctx)
static

Definition at line 178 of file imc.c.

Referenced by flush().

static void imc_calculate_coeffs ( IMCContext q,
float *  flcoeffs1,
float *  flcoeffs2,
int bandWidthT,
float *  flcoeffs3,
float *  flcoeffs5 
)
static

Definition at line 274 of file imc.c.

Referenced by imc_decode_block().

static void imc_read_level_coeffs ( IMCContext q,
int  stream_format_code,
int levlCoeffs 
)
static

Definition at line 329 of file imc.c.

Referenced by imc_decode_block().

static void imc_read_level_coeffs_raw ( IMCContext q,
int  stream_format_code,
int levlCoeffs 
)
static

Definition at line 357 of file imc.c.

Referenced by imc_decode_block().

static void imc_decode_level_coefficients ( IMCContext q,
int levlCoeffBuf,
float *  flcoeffs1,
float *  flcoeffs2 
)
static

Definition at line 368 of file imc.c.

Referenced by imc_decode_block().

static void imc_decode_level_coefficients2 ( IMCContext q,
int levlCoeffBuf,
float *  old_floor,
float *  flcoeffs1,
float *  flcoeffs2 
)
static

Definition at line 402 of file imc.c.

Referenced by imc_decode_block().

static void imc_decode_level_coefficients_raw ( IMCContext q,
int levlCoeffBuf,
float *  flcoeffs1,
float *  flcoeffs2 
)
static

Definition at line 422 of file imc.c.

Referenced by imc_decode_block().

static int bit_allocation ( IMCContext q,
IMCChannel chctx,
int  stream_format_code,
int  freebits,
int  flag 
)
static

Perform bit allocation depending on bits available.

Definition at line 447 of file imc.c.

Referenced by imc_decode_block().

static void imc_get_skip_coeff ( IMCContext q,
IMCChannel chctx 
)
static

Definition at line 623 of file imc.c.

Referenced by imc_refine_bit_allocation().

static void imc_adjust_bit_allocation ( IMCContext q,
IMCChannel chctx,
int  summer 
)
static

Increase highest' band coefficient sizes as some bits won't be used.

Definition at line 679 of file imc.c.

Referenced by imc_refine_bit_allocation().

static void imc_imdct256 ( IMCContext q,
IMCChannel chctx,
int  channels 
)
static

Definition at line 721 of file imc.c.

Referenced by imc_decode_block().

static int inverse_quant_coeff ( IMCContext q,
IMCChannel chctx,
int  stream_format_code 
)
static

Definition at line 754 of file imc.c.

Referenced by imc_decode_block().

static void imc_get_coeffs ( AVCodecContext avctx,
IMCContext q,
IMCChannel chctx 
)
static

Definition at line 794 of file imc.c.

Referenced by imc_decode_block().

static void imc_refine_bit_allocation ( IMCContext q,
IMCChannel chctx 
)
static

Definition at line 822 of file imc.c.

Referenced by imc_decode_block().

static int imc_decode_block ( AVCodecContext avctx,
IMCContext q,
int  ch 
)
static

Definition at line 866 of file imc.c.

Referenced by imc_decode_frame().

static int imc_decode_frame ( AVCodecContext avctx,
void data,
int got_frame_ptr,
AVPacket avpkt 
)
static

Definition at line 1015 of file imc.c.

Referenced by flush().

static av_cold int imc_decode_close ( AVCodecContext avctx)
static

Definition at line 1062 of file imc.c.

Referenced by flush().

static av_cold void flush ( AVCodecContext avctx)
static

Definition at line 1071 of file imc.c.

Variable Documentation

VLC huffman_vlc[4][4]
static

Definition at line 111 of file imc.c.

const int vlc_offsets[17]
static
Initial value:
= {
0, 640, 1156, 1732, 2308, 2852, 3396, 3924,
4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE
}
#define VLC_TABLES_SIZE
Definition: imc.c:113

Definition at line 115 of file imc.c.

Referenced by imc_decode_init().

VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2]
static

Definition at line 120 of file imc.c.

Referenced by imc_decode_init(), and unpack_dct_coeffs().