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"

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

◆ IMC_BLOCK_SIZE

#define IMC_BLOCK_SIZE 64

Definition at line 50 of file imc.c.

Referenced by imc_decode_frame().

◆ IMC_FRAME_ID

#define IMC_FRAME_ID 0x21

Definition at line 51 of file imc.c.

◆ BANDS

#define BANDS 32

Definition at line 52 of file imc.c.

Referenced by bit_allocation(), imc_adjust_bit_allocation(), imc_calculate_coeffs(), imc_decode_block(), imc_decode_init(), imc_decode_level_coefficients(), imc_decode_level_coefficients2(), imc_decode_level_coefficients_raw(), imc_get_coeffs(), imc_get_skip_coeff(), imc_read_level_coeffs(), imc_read_level_coeffs_raw(), imc_refine_bit_allocation(), inverse_quant_coeff(), mpc7_decode_frame(), mpc7_decode_init(), and mpc8_decode_init().

◆ COEFFS

#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().

◆ VLC_TABLES_SIZE

#define VLC_TABLES_SIZE 9512

Definition at line 111 of file imc.c.

Function Documentation

◆ freq2bark()

static double freq2bark ( double freq )

inlinestatic

Definition at line 120 of file imc.c.

Referenced by iac_generate_tabs().

◆ iac_generate_tabs()

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

static

Definition at line 125 of file imc.c.

Referenced by imc_decode_init().

◆ imc_decode_init()

static av_cold int imc_decode_init ( AVCodecContext * avctx )

static

Definition at line 176 of file imc.c.

Referenced by flush().

◆ imc_calculate_coeffs()

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

static

Definition at line 272 of file imc.c.

Referenced by imc_decode_block().

◆ imc_read_level_coeffs()

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

static

Definition at line 327 of file imc.c.

Referenced by imc_decode_block().

◆ imc_read_level_coeffs_raw()

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

static

Definition at line 355 of file imc.c.

Referenced by imc_decode_block().

◆ imc_decode_level_coefficients()

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

static

Definition at line 366 of file imc.c.

Referenced by imc_decode_block().

◆ imc_decode_level_coefficients2()

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

static

Definition at line 400 of file imc.c.

Referenced by imc_decode_block().

◆ imc_decode_level_coefficients_raw()

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

static

Definition at line 420 of file imc.c.

Referenced by imc_decode_block().

◆ bit_allocation()

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 445 of file imc.c.

Referenced by imc_decode_block().

◆ imc_get_skip_coeff()

static void imc_get_skip_coeff	(	IMCContext *	q,
		IMCChannel *	chctx
	)

static

Definition at line 621 of file imc.c.

Referenced by imc_refine_bit_allocation().

◆ imc_adjust_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 677 of file imc.c.

Referenced by imc_refine_bit_allocation().

◆ imc_imdct256()

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

static

Definition at line 719 of file imc.c.

Referenced by imc_decode_block().

◆ inverse_quant_coeff()

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

static

Definition at line 752 of file imc.c.

Referenced by imc_decode_block().

◆ imc_get_coeffs()

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

static

Definition at line 792 of file imc.c.

Referenced by imc_decode_block().

◆ imc_refine_bit_allocation()

static void imc_refine_bit_allocation	(	IMCContext *	q,
		IMCChannel *	chctx
	)

static

Definition at line 820 of file imc.c.

Referenced by imc_decode_block().

◆ imc_decode_block()

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

static

Definition at line 864 of file imc.c.

Referenced by imc_decode_frame().

◆ imc_decode_frame()

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

static

Definition at line 1013 of file imc.c.

Referenced by flush().

◆ imc_decode_close()

static av_cold int imc_decode_close ( AVCodecContext * avctx )

static

Definition at line 1058 of file imc.c.

Referenced by flush().

◆ flush()

static av_cold void flush ( AVCodecContext * avctx )

static

Definition at line 1068 of file imc.c.

Variable Documentation

◆ huffman_vlc

VLC huffman_vlc[4][4]

static

Definition at line 109 of file imc.c.

◆ vlc_offsets

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
}

Definition at line 113 of file imc.c.

Referenced by imc_decode_init().

◆ vlc_tables

VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2]

static

Definition at line 118 of file imc.c.

Referenced by imc_decode_init(), and ir2_decode_init().

Data Structures

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ IMC_BLOCK_SIZE

◆ IMC_FRAME_ID

◆ BANDS

◆ COEFFS

◆ VLC_TABLES_SIZE

Function Documentation

◆ freq2bark()

◆ iac_generate_tabs()

◆ imc_decode_init()

◆ imc_calculate_coeffs()

◆ imc_read_level_coeffs()

◆ imc_read_level_coeffs_raw()

◆ imc_decode_level_coefficients()

◆ imc_decode_level_coefficients2()

◆ imc_decode_level_coefficients_raw()

◆ bit_allocation()

◆ imc_get_skip_coeff()

◆ imc_adjust_bit_allocation()

◆ imc_imdct256()

◆ inverse_quant_coeff()

◆ imc_get_coeffs()

◆ imc_refine_bit_allocation()

◆ imc_decode_block()

◆ imc_decode_frame()

◆ imc_decode_close()

◆ flush()

Variable Documentation

◆ huffman_vlc

◆ vlc_offsets

◆ vlc_tables