libavcodec/cook.c File Reference

Cook compatible decoder. More...

#include <math.h>
#include <stddef.h>
#include <stdio.h>
#include "libavutil/lfg.h"
#include "libavutil/random_seed.h"
#include "avcodec.h"
#include "get_bits.h"
#include "dsputil.h"
#include "bytestream.h"
#include "fft.h"
#include "cookdata.h"

Go to the source code of this file.

Data Structures

struct cook_gains

struct COOKSubpacket

struct cook

Defines

#define MONO   0x1000001

#define STEREO   0x1000002

#define JOINT_STEREO   0x1000003

#define MC_COOK   0x2000000

#define SUBBAND_SIZE   20

#define MAX_SUBPACKETS   5

#define DECODE_BYTES_PAD1(bytes)   (3 - ((bytes)+3) % 4)

Cook indata decoding, every 32 bits are XORed with 0x37c511f2.

#define DECODE_BYTES_PAD2(bytes)   ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))

Typedefs

typedef struct cook COOKContext

Functions

static av_cold void init_pow2table (void)

static av_cold void init_gain_table (COOKContext *q)

static av_cold int init_cook_vlc_tables (COOKContext *q)

static av_cold int init_cook_mlt (COOKContext *q)

static const float * maybe_reformat_buffer32 (COOKContext *q, const float *ptr, int n)

static av_cold void init_cplscales_table (COOKContext *q)

static int decode_bytes (const uint8_t *inbuffer, uint8_t *out, int bytes)

static av_cold int cook_decode_close (AVCodecContext *avctx)

Cook uninit.

static void decode_gain_info (GetBitContext *gb, int *gaininfo)

Fill the gain array for the timedomain quantization.

static void decode_envelope (COOKContext *q, COOKSubpacket *p, int *quant_index_table)

Create the quant index table needed for the envelope.

static void categorize (COOKContext *q, COOKSubpacket *p, int *quant_index_table, int *category, int *category_index)

Calculate the category and category_index vector.

static void expand_category (COOKContext *q, int *category, int *category_index)

Expand the category vector.

static void scalar_dequant_float (COOKContext *q, int index, int quant_index, int *subband_coef_index, int *subband_coef_sign, float *mlt_p)

The real requantization of the mltcoefs.

static int unpack_SQVH (COOKContext *q, COOKSubpacket *p, int category, int *subband_coef_index, int *subband_coef_sign)

Unpack the subband_coef_index and subband_coef_sign vectors.

static void decode_vectors (COOKContext *q, COOKSubpacket *p, int *category, int *quant_index_table, float *mlt_buffer)

Fill the mlt_buffer with mlt coefficients.

static void mono_decode (COOKContext *q, COOKSubpacket *p, float *mlt_buffer)

function for decoding mono data

static void interpolate_float (COOKContext *q, float *buffer, int gain_index, int gain_index_next)

the actual requantization of the timedomain samples

static void imlt_window_float (COOKContext *q, float *buffer1, cook_gains *gains_ptr, float *previous_buffer)

Apply transform window, overlap buffers.

static void imlt_gain (COOKContext *q, float *inbuffer, cook_gains *gains_ptr, float *previous_buffer)

The modulated lapped transform, this takes transform coefficients and transforms them into timedomain samples.

static void decouple_info (COOKContext *q, COOKSubpacket *p, int *decouple_tab)

function for getting the jointstereo coupling information

static void decouple_float (COOKContext *q, COOKSubpacket *p, int subband, float f1, float f2, float *decode_buffer, float *mlt_buffer1, float *mlt_buffer2)

static void joint_decode (COOKContext *q, COOKSubpacket *p, float *mlt_buffer1, float *mlt_buffer2)

function for decoding joint stereo data

static void decode_bytes_and_gain (COOKContext *q, COOKSubpacket *p, const uint8_t *inbuffer, cook_gains *gains_ptr)

First part of subpacket decoding: decode raw stream bytes and read gain info.

static void saturate_output_float (COOKContext *q, int chan, int16_t *out)

Saturate the output signal to signed 16bit integers.

static void mlt_compensate_output (COOKContext *q, float *decode_buffer, cook_gains *gains, float *previous_buffer, int16_t *out, int chan)

Final part of subpacket decoding: Apply modulated lapped transform, gain compensation, clip and convert to integer.

static void decode_subpacket (COOKContext *q, COOKSubpacket *p, const uint8_t *inbuffer, int16_t *outbuffer)

Cook subpacket decoding.

static int cook_decode_frame (AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)

Cook frame decoding.

static av_cold int cook_count_channels (unsigned int mask)

static av_cold int cook_decode_init (AVCodecContext *avctx)

Cook initialization.

Variables

static float pow2tab [127]

static float rootpow2tab [127]

AVCodec cook_decoder

Detailed Description

Cook compatible decoder.

Bastardization of the G.722.1 standard. This decoder handles RealNetworks, RealAudio G2 data. Cook is identified by the codec name cook in RM files.

To use this decoder, a calling application must supply the extradata bytes provided from the RM container; 8+ bytes for mono streams and 16+ for stereo streams (maybe more).

Codec technicalities (all this assume a buffer length of 1024): Cook works with several different techniques to achieve its compression. In the timedomain the buffer is divided into 8 pieces and quantized. If two neighboring pieces have different quantization index a smooth quantization curve is used to get a smooth overlap between the different pieces. To get to the transformdomain Cook uses a modulated lapped transform. The transform domain has 50 subbands with 20 elements each. This means only a maximum of 50*20=1000 coefficients are used out of the 1024 available.

Definition in file cook.c.

Define Documentation

#define DECODE_BYTES_PAD1 ( bytes ) (3 - ((bytes)+3) % 4)

Cook indata decoding, every 32 bits are XORed with 0x37c511f2.

Why? No idea, some checksum/error detection method maybe.

Out buffer size: extra bytes are needed to cope with padding/misalignment. Subpackets passed to the decoder can contain two, consecutive half-subpackets, of identical but arbitrary size. 1234 1234 1234 1234 extraA extraB Case 1: AAAA BBBB 0 0 Case 2: AAAA ABBB BB-- 3 3 Case 3: AAAA AABB BBBB 2 2 Case 4: AAAA AAAB BBBB BB-- 1 5

Nice way to waste CPU cycles.

Parameters:

	inbuffer	pointer to byte array of indata
	out	pointer to byte array of outdata
	bytes	number of bytes

Definition at line 307 of file cook.c.


Data Structures
struct	cook_gains
struct	COOKSubpacket
struct	cook
Defines
#define	MONO 0x1000001
#define	STEREO 0x1000002
#define	JOINT_STEREO 0x1000003
#define	MC_COOK 0x2000000
#define	SUBBAND_SIZE 20
#define	MAX_SUBPACKETS 5
#define	DECODE_BYTES_PAD1(bytes) (3 - ((bytes)+3) % 4)
	Cook indata decoding, every 32 bits are XORed with 0x37c511f2.
#define	DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
Typedefs
typedef struct cook	COOKContext
Functions
static av_cold void	init_pow2table (void)
static av_cold void	init_gain_table (COOKContext *q)
static av_cold int	init_cook_vlc_tables (COOKContext *q)
static av_cold int	init_cook_mlt (COOKContext *q)
static const float *	maybe_reformat_buffer32 (COOKContext q, const float ptr, int n)
static av_cold void	init_cplscales_table (COOKContext *q)
static int	decode_bytes (const uint8_t inbuffer, uint8_t out, int bytes)
static av_cold int	cook_decode_close (AVCodecContext *avctx)
	Cook uninit.
static void	decode_gain_info (GetBitContext gb, int gaininfo)
	Fill the gain array for the timedomain quantization.
static void	decode_envelope (COOKContext q, COOKSubpacket p, int *quant_index_table)
	Create the quant index table needed for the envelope.
static void	categorize (COOKContext q, COOKSubpacket p, int quant_index_table, int category, int *category_index)
	Calculate the category and category_index vector.
static void	expand_category (COOKContext q, int category, int *category_index)
	Expand the category vector.
static void	scalar_dequant_float (COOKContext q, int index, int quant_index, int subband_coef_index, int subband_coef_sign, float mlt_p)
	The real requantization of the mltcoefs.
static int	unpack_SQVH (COOKContext q, COOKSubpacket p, int category, int subband_coef_index, int subband_coef_sign)
	Unpack the subband_coef_index and subband_coef_sign vectors.
static void	decode_vectors (COOKContext q, COOKSubpacket p, int category, int quant_index_table, float *mlt_buffer)
	Fill the mlt_buffer with mlt coefficients.
static void	mono_decode (COOKContext q, COOKSubpacket p, float *mlt_buffer)
	function for decoding mono data
static void	interpolate_float (COOKContext q, float buffer, int gain_index, int gain_index_next)
	the actual requantization of the timedomain samples
static void	imlt_window_float (COOKContext q, float buffer1, cook_gains gains_ptr, float previous_buffer)
	Apply transform window, overlap buffers.
static void	imlt_gain (COOKContext q, float inbuffer, cook_gains gains_ptr, float previous_buffer)
	The modulated lapped transform, this takes transform coefficients and transforms them into timedomain samples.
static void	decouple_info (COOKContext q, COOKSubpacket p, int *decouple_tab)
	function for getting the jointstereo coupling information
static void	decouple_float (COOKContext q, COOKSubpacket p, int subband, float f1, float f2, float decode_buffer, float mlt_buffer1, float *mlt_buffer2)
static void	joint_decode (COOKContext q, COOKSubpacket p, float mlt_buffer1, float mlt_buffer2)
	function for decoding joint stereo data
static void	decode_bytes_and_gain (COOKContext q, COOKSubpacket p, const uint8_t inbuffer, cook_gains gains_ptr)
	First part of subpacket decoding: decode raw stream bytes and read gain info.
static void	saturate_output_float (COOKContext q, int chan, int16_t out)
	Saturate the output signal to signed 16bit integers.
static void	mlt_compensate_output (COOKContext q, float decode_buffer, cook_gains gains, float previous_buffer, int16_t *out, int chan)
	Final part of subpacket decoding: Apply modulated lapped transform, gain compensation, clip and convert to integer.
static void	decode_subpacket (COOKContext q, COOKSubpacket p, const uint8_t inbuffer, int16_t outbuffer)
	Cook subpacket decoding.
static int	cook_decode_frame (AVCodecContext avctx, void data, int data_size, AVPacket avpkt)
	Cook frame decoding.
static av_cold int	cook_count_channels (unsigned int mask)
static av_cold int	cook_decode_init (AVCodecContext *avctx)
	Cook initialization.
Variables
static float	pow2tab [127]
static float	rootpow2tab [127]
AVCodec	cook_decoder

static void categorize	(	COOKContext *	q,
		COOKSubpacket *	p,
		int *	quant_index_table,
		int *	category,
		int *	category_index
	)			`[static]`

	q	pointer to the COOKContext
	quant_index_table	pointer to the array
	category	pointer to the category array
	category_index	pointer to the category_index array

static int cook_decode_frame	(	AVCodecContext *	avctx,
		void *	data,
		int *	data_size,
		AVPacket *	avpkt
	)			`[static]`

static int decode_bytes	(	const uint8_t *	inbuffer,
		uint8_t *	out,
		int	bytes
	)			`[inline, static]`

static void decode_bytes_and_gain	(	COOKContext *	q,
		COOKSubpacket *	p,
		const uint8_t *	inbuffer,
		cook_gains *	gains_ptr
	)			`[inline, static]`

	q	pointer to the COOKContext
	inbuffer	pointer to raw stream data
	gain_ptr	array of current/prev gain pointers

static void decode_envelope	(	COOKContext *	q,
		COOKSubpacket *	p,
		int *	quant_index_table
	)			`[static]`

static void decode_gain_info	(	GetBitContext *	gb,
		int *	gaininfo
	)			`[static]`

	q	pointer to the COOKContext
	gaininfo[9]	array of gain indexes

static void decode_subpacket	(	COOKContext *	q,
		COOKSubpacket *	p,
		const uint8_t *	inbuffer,
		int16_t *	outbuffer
	)			`[static]`

	q	pointer to the COOKContext
	inbuffer	pointer to the inbuffer
	sub_packet_size	subpacket size
	outbuffer	pointer to the outbuffer

static void decode_vectors	(	COOKContext *	q,
		COOKSubpacket *	p,
		int *	category,
		int *	quant_index_table,
		float *	mlt_buffer
	)			`[static]`

static void decouple_float	(	COOKContext *	q,
		COOKSubpacket *	p,
		int	subband,
		float	f1,
		float	f2,
		float *	decode_buffer,
		float *	mlt_buffer1,
		float *	mlt_buffer2
	)			`[static]`

static void decouple_info	(	COOKContext *	q,
		COOKSubpacket *	p,
		int *	decouple_tab
	)			`[static]`

static void expand_category	(	COOKContext *	q,
		int *	category,
		int *	category_index
	)			`[inline, static]`

static void imlt_gain	(	COOKContext *	q,
		float *	inbuffer,
		cook_gains *	gains_ptr,
		float *	previous_buffer
	)			`[static]`

	q	pointer to the COOKContext
	inbuffer	pointer to the mltcoefficients
	gains_ptr	current and previous gains
	previous_buffer	pointer to the previous buffer to be used for overlapping

static void imlt_window_float	(	COOKContext *	q,
		float *	buffer1,
		cook_gains *	gains_ptr,
		float *	previous_buffer
	)			`[static]`

static void interpolate_float	(	COOKContext *	q,
		float *	buffer,
		int	gain_index,
		int	gain_index_next
	)			`[static]`

libavcodec/cook.c File Reference

Data Structures

Defines

Typedefs

Functions

Variables

Detailed Description

Define Documentation

Typedef Documentation

Function Documentation

Variable Documentation

	q	pointer to the COOKContext
	buffer	pointer to the timedomain buffer
	gain_index	index for the block multiplier
	gain_index_next	index for the next block multiplier

static void joint_decode	(	COOKContext *	q,
		COOKSubpacket *	p,
		float *	mlt_buffer1,
		float *	mlt_buffer2
	)			`[static]`

	q	pointer to the COOKContext
	mlt_buffer1	pointer to left channel mlt coefficients
	mlt_buffer2	pointer to right channel mlt coefficients

static const float* maybe_reformat_buffer32	(	COOKContext *	q,
		const float *	ptr,
		int	n
	)			`[static]`

static void mlt_compensate_output	(	COOKContext *	q,
		float *	decode_buffer,
		cook_gains *	gains,
		float *	previous_buffer,
		int16_t *	out,
		int	chan
	)			`[inline, static]`

	q	pointer to the COOKContext
	decode_buffer	pointer to the mlt coefficients
	gain_ptr	array of current/prev gain pointers
	previous_buffer	pointer to the previous buffer to be used for overlapping
	out	pointer to the output buffer
	chan	0: left or single channel, 1: right channel

static void mono_decode	(	COOKContext *	q,
		COOKSubpacket *	p,
		float *	mlt_buffer
	)			`[static]`

	q	pointer to the COOKContext
	mlt_buffer	pointer to mlt coefficients

static void saturate_output_float	(	COOKContext *	q,
		int	chan,
		int16_t *	out
	)			`[static]`

	q	pointer to the COOKContext
	chan	channel to saturate
	out	pointer to the output vector