JPEG Decoder is based on libjpeg library. More...

Classes
struct	JQUANT_TBL

struct	JHUFF_TBL

struct	jpeg_component_info

struct	jpeg_scan_info

struct	jpeg_marker_struct

struct	jpeg_common_struct

struct	jpeg_compress_struct

struct	jpeg_decompress_struct

struct	jpeg_error_mgr

struct	jpeg_progress_mgr

struct	jpeg_destination_mgr

struct	jpeg_source_mgr

struct	jpeg_memory_mgr

Macros
#define	JPEG_LIB_VERSION 90 /* Compatibility version 9.0 */

#define	JPEG_LIB_VERSION_MAJOR 9

#define	JPEG_LIB_VERSION_MINOR 5

#define	DCTSIZE 8 /* The basic DCT block is 8x8 coefficients */

#define	DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */

#define	NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */

#define	NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */

#define	NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */

#define	MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */

#define	MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */

#define	C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */

#define	D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */

#define	JDCT_DEFAULT JDCT_ISLOW

#define	JDCT_FASTEST JDCT_IFAST

#define	jpeg_common_fields

#define	JPOOL_PERMANENT 0 /* lasts until master record is destroyed */

#define	JPOOL_IMAGE 1 /* lasts until done with image/datastream */

#define	JPOOL_NUMPOOLS 2

#define	JPP(arglist) arglist

#define	jpeg_create_compress(cinfo)

#define	jpeg_create_decompress(cinfo)

#define	JPEG_SUSPENDED 0

#define	JPEG_HEADER_OK 1

#define	JPEG_HEADER_TABLES_ONLY 2

#define	JPEG_REACHED_SOS 1 /* Reached start of new scan */

#define	JPEG_REACHED_EOI 2 /* Reached end of image */

#define	JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */

#define	JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */

#define	JPEG_RST0 0xD0 /* RST0 marker code */

#define	JPEG_EOI 0xD9 /* EOI marker code */

#define	JPEG_APP0 0xE0 /* APP0 marker code */

#define	JPEG_COM 0xFE /* COM marker code */

Typedefs
typedef JSAMPLE FAR *	JSAMPROW

typedef JSAMPROW *	JSAMPARRAY

typedef JSAMPARRAY *	JSAMPIMAGE

typedef JCOEF	JBLOCK[DCTSIZE2]

typedef JBLOCK FAR *	JBLOCKROW

typedef JBLOCKROW *	JBLOCKARRAY

typedef JBLOCKARRAY *	JBLOCKIMAGE

typedef JCOEF FAR *	JCOEFPTR

typedef struct jpeg_marker_struct FAR *	jpeg_saved_marker_ptr

typedef struct jpeg_common_struct *	j_common_ptr

typedef struct jpeg_compress_struct *	j_compress_ptr

typedef struct jpeg_decompress_struct *	j_decompress_ptr

typedef struct jvirt_sarray_control *	jvirt_sarray_ptr

typedef struct jvirt_barray_control *	jvirt_barray_ptr

Enumerations
enum	J_COLOR_SPACE { JCS_UNKNOWN , JCS_GRAYSCALE , JCS_RGB , JCS_YCbCr , JCS_CbYCrY , JCS_CMYK , JCS_YCCK , JCS_BG_RGB , JCS_BG_YCC }

enum	J_COLOR_TRANSFORM { JCT_NONE = 0 , JCT_SUBTRACT_GREEN = 1 }

enum	J_DCT_METHOD { JDCT_ISLOW , JDCT_IFAST , JDCT_FLOAT }

enum	J_DITHER_MODE { JDITHER_NONE , JDITHER_ORDERED , JDITHER_FS }

Functions
typedef	JMETHOD (boolean, jpeg_marker_parser_method,(j_decompress_ptr cinfo))

struct jpeg_error_mgr *	jpeg_std_error (struct jpeg_error_mgr *err)

void	jpeg_CreateCompress (j_compress_ptr cinfo, int version, size_t structsize)

void	jpeg_CreateDecompress (j_decompress_ptr cinfo, int version, size_t structsize)

void	jpeg_destroy_compress (j_compress_ptr cinfo)

void	jpeg_destroy_decompress (j_decompress_ptr cinfo)

void	jpeg_stdio_dest (j_compress_ptr cinfo, FILE *outfile)

void	jpeg_stdio_src (j_decompress_ptr cinfo, FILE *infile)

void	jpeg_fd_src (j_decompress_ptr cinfo, int infd)

void	jpeg_mem_dest (j_compress_ptr cinfo, unsigned char *outbuffer, size_t outsize)

void	jpeg_mem_src (j_decompress_ptr cinfo, const unsigned char *inbuffer, size_t insize)

void	jpeg_set_defaults (j_compress_ptr cinfo)

void	jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace)

void	jpeg_default_colorspace (j_compress_ptr cinfo)

void	jpeg_set_quality (j_compress_ptr cinfo, int quality, boolean force_baseline)

void	jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor, boolean force_baseline)

void	jpeg_default_qtables (j_compress_ptr cinfo, boolean force_baseline)

void	jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl, const unsigned int *basic_table, int scale_factor, boolean force_baseline)

int	jpeg_quality_scaling (int quality)

void	jpeg_simple_progression (j_compress_ptr cinfo)

void	jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)

JQUANT_TBL *	jpeg_alloc_quant_table (j_common_ptr cinfo)

JHUFF_TBL *	jpeg_alloc_huff_table (j_common_ptr cinfo)

JHUFF_TBL *	jpeg_std_huff_table (j_common_ptr cinfo, boolean isDC, int tblno)

void	jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables)

JDIMENSION	jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines, JDIMENSION num_lines)

void	jpeg_finish_compress (j_compress_ptr cinfo)

void	jpeg_calc_jpeg_dimensions (j_compress_ptr cinfo)

JDIMENSION	jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data, JDIMENSION num_lines)

void	jpeg_write_marker (j_compress_ptr cinfo, int marker, const JOCTET *dataptr, unsigned int datalen)

void	jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)

void	jpeg_write_m_byte (j_compress_ptr cinfo, int val)

void	jpeg_write_tables (j_compress_ptr cinfo)

int	jpeg_read_header (j_decompress_ptr cinfo, boolean require_image)

boolean	jpeg_start_decompress (j_decompress_ptr cinfo)

JDIMENSION	jpeg_read_scanlines (j_decompress_ptr cinfo, JSAMPARRAY scanlines, JDIMENSION max_lines)

JDIMENSION	jpeg_read_mcus (j_decompress_ptr cinfo, JSAMPARRAY mcus, JDIMENSION max_lines, JDIMENSION *offset)

boolean	jpeg_finish_decompress (j_decompress_ptr cinfo)

JDIMENSION	jpeg_read_raw_data (j_decompress_ptr cinfo, JSAMPIMAGE data, JDIMENSION max_lines)

boolean	jpeg_has_multiple_scans (j_decompress_ptr cinfo)

boolean	jpeg_start_output (j_decompress_ptr cinfo, int scan_number)

boolean	jpeg_finish_output (j_decompress_ptr cinfo)

boolean	jpeg_input_complete (j_decompress_ptr cinfo)

void	jpeg_new_colormap (j_decompress_ptr cinfo)

int	jpeg_consume_input (j_decompress_ptr cinfo)

void	jpeg_core_output_dimensions (j_decompress_ptr cinfo)

void	jpeg_calc_output_dimensions (j_decompress_ptr cinfo)

void	jpeg_save_markers (j_decompress_ptr cinfo, int marker_code, unsigned int length_limit)

void	jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code, jpeg_marker_parser_method routine)

jvirt_barray_ptr *	jpeg_read_coefficients (j_decompress_ptr cinfo)

void	jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr *coef_arrays)

void	jpeg_copy_critical_parameters (j_decompress_ptr srcinfo, j_compress_ptr dstinfo)

void	jpeg_abort_compress (j_compress_ptr cinfo)

void	jpeg_abort_decompress (j_decompress_ptr cinfo)

void	jpeg_abort (j_common_ptr cinfo)

void	jpeg_destroy (j_common_ptr cinfo)

boolean	jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired)

Detailed Description

JPEG Decoder is based on libjpeg library.

Macro Definition Documentation

◆ jpeg_common_fields

#define jpeg_common_fields

Value:

  struct jpeg_error_mgr * err;  /* Error handler module */\
  struct jpeg_memory_mgr * mem; /* Memory manager module */\
  struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
  void * client_data;       /* Available for use by application */\
  boolean is_decompressor;  /* So common code can tell which is which */\
  int global_state      /* For checking call sequence validity */

◆ jpeg_create_compress

#define jpeg_create_compress ( cinfo )

Value:

jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \

(size_t) sizeof(struct jpeg_compress_struct))

jpeg_compress_struct

Definition: jpeglib.h:312

◆ jpeg_create_decompress

#define jpeg_create_decompress ( cinfo )

Value:

jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \

(size_t) sizeof(struct jpeg_decompress_struct))

jpeg_decompress_struct

Definition: jpeglib.h:480

◆ JPEG_SUSPENDED

#define JPEG_SUSPENDED 0

Suspended due to lack of input data

◆ JPEG_HEADER_OK

#define JPEG_HEADER_OK 1

Found valid image datastream

◆ JPEG_HEADER_TABLES_ONLY

#define JPEG_HEADER_TABLES_ONLY 2

Found valid table-specs-only datastream

Function Documentation

◆ jpeg_destroy_decompress()

void jpeg_destroy_decompress ( j_decompress_ptr cinfo )

Release JPEG decompression object.

Parameters

[in,out] cinfo Pointer to JPEG decompression object

Returns: void

◆ jpeg_stdio_src()

void jpeg_stdio_src	(	j_decompress_ptr	cinfo,
		FILE *	infile
	)

Specify a file to JPEG data source by file pointer.

Note: Caller is responsible for opening the file before and closing after.

Parameters

[in,out]	cinfo	Pointer toJPEG decompression object
[in]	infile	JPEG file pointer to be decoded

Returns: void

◆ jpeg_fd_src()

void jpeg_fd_src	(	j_decompress_ptr	cinfo,
		int	infd
	)

Specify a file to JPEG data source by file descriptor.

Note: Caller is responsible for opening the file before and closing after.

Parameters

[in,out]	cinfo	Pointer to JPEG decompression object
[in]	infd	JPEG file descriptor to be decoded

Returns: void

◆ jpeg_mem_src()

void jpeg_mem_src	(	j_decompress_ptr	cinfo,
		const unsigned char *	inbuffer,
		size_t	insize
	)

Specify a buffer to JPEG data source.

Note: The input buffer must contain the whole JPEG data.

Parameters

[in,out]	cinfo	Pointer to JPEG decompression object
[in]	inbuffer	Pointer to buffer which include the whole JPEG data
[in]	insize	Size of inbuffer

Returns: void

◆ jpeg_read_header()

int jpeg_read_header	(	j_decompress_ptr	cinfo,
		boolean	require_image
	)

Read JPEG header.

Note: Application need to complete one of jpeg_stdio_src, jpeg_fd_src or jpeg_mem_src in order to complete this API and proceed decode.

Parameters

[in,out]	cinfo	Pointer to JPEG decompression object
[in]	require_image	True means that decoder handle error and do not return in no-image case.

Returns

return value	meaning
JPEG_SUSPENDED	Suspended due to lack of input data. This value can be returned if application used jpeg_mem_src for JPEG data source input.
JPEG_HEADER_OK	Found valid image datastream
JPEG_HEADER_TABLES_ONLY	Found valid table-specs-only datastream. In require_image = true case, this value cannot be returned.

◆ jpeg_start_decompress()

boolean jpeg_start_decompress ( j_decompress_ptr cinfo )

Start decompression.

Note: Application need to complete jpeg_read_header in order to complete this API and proceed decode.

Parameters

[in,out] cinfo Pointer to JPEG decompression object

Returns

return value	meaning
FALSE	Suspended due to lack of input data. This value can be returned if application used jpeg_mem_src for JPEG data source input.
TRUE	Success

◆ jpeg_read_scanlines()

JDIMENSION jpeg_read_scanlines	(	j_decompress_ptr	cinfo,
		JSAMPARRAY	scanlines,
		JDIMENSION	max_lines
	)

Read decompressed image data by scanline. Maximum readable number of lines is the value of max_lines. The number of lines actually read is notified by the return value.

Note: jpeg_start_decompress must be completed before calling this API.

Parameters

[in,out]	cinfo	Pointer to JPEG decompression object
[out]	scanlines	Pointer to buffer array
[in]	max_lines	Array size of scanlines

Returns: The number of lines actually read.

◆ jpeg_read_mcus()

JDIMENSION jpeg_read_mcus	(	j_decompress_ptr	cinfo,
		JSAMPARRAY	mcus,
		JDIMENSION	max_lines,
		JDIMENSION *	offset
	)

Read decoded data of some mcus from the JPEG decompressor.

Note: jpeg_start_decompress must be completed before calling this API. Currently, max_lines must be the size of one mcu.

Parameters

[in,out]	cinfo	Pointer to JPEG decompression object
[out]	mcus	Pointer to buffer array
[in]	max_lines	Array size of mcus
[out]	offset	Position of the read mcu from the top of image

Returns: The number of mcus actually read.

◆ jpeg_finish_decompress()

boolean jpeg_finish_decompress ( j_decompress_ptr cinfo )

Finish JPEG decompression.

Parameters

[in] cinfo Pointer to JPEG decompression object

Returns

return value	meaning
FALSE	Suspended due to lack of input data. This value can be returned if application used jpeg_mem_src for JPEG data source input.
TRUE	Success

Classes

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ jpeg_common_fields

◆ jpeg_create_compress

◆ jpeg_create_decompress

◆ JPEG_SUSPENDED

◆ JPEG_HEADER_OK

◆ JPEG_HEADER_TABLES_ONLY

Function Documentation

◆ jpeg_destroy_decompress()

◆ jpeg_stdio_src()

◆ jpeg_fd_src()

◆ jpeg_mem_src()

◆ jpeg_read_header()

◆ jpeg_start_decompress()

◆ jpeg_read_scanlines()

◆ jpeg_read_mcus()

◆ jpeg_finish_decompress()