jpeg_data: buffer with input / output jpeg
len: Length of jpeg buffer
itype: Y4M_ILACE_NONE: Not interlaced
Y4M_ILACE_TOP_FIRST: Interlaced, top-field-first
Y4M_ILACE_BOTTOM_FIRST: Interlaced, bottom-field-first
ctype Chroma format for decompression. More...

Macros
#define	Y4M_ILACE_NONE 0 /** non-interlaced, progressive frame */

#define	Y4M_ILACE_TOP_FIRST 1 /** interlaced, top-field first */

#define	Y4M_ILACE_BOTTOM_FIRST 2 /** interlaced, bottom-field first */

#define	Y4M_ILACE_MIXED 3 /** mixed, "refer to frame header" */

#define	Y4M_CHROMA_420JPEG 0 /** 4:2:0, H/V centered, for JPEG/MPEG-1 */

#define	Y4M_CHROMA_420MPEG2 1 /** 4:2:0, H cosited, for MPEG-2 */

#define	Y4M_CHROMA_420PALDV 2 /** 4:2:0, alternating Cb/Cr, for PAL-DV */

#define	Y4M_CHROMA_444 3 /** 4:4:4, no subsampling, phew. */

#define	Y4M_CHROMA_422 4 /** 4:2:2, H cosited */

#define	Y4M_CHROMA_411 5 /** 4:1:1, H cosited */

#define	Y4M_CHROMA_MONO 6 /** luma plane only */

#define	Y4M_CHROMA_444ALPHA 7 /** 4:4:4 with an alpha channel */

Functions
int	decode_jpeg_raw (unsigned char jpeg_data, int len, int itype, int ctype, unsigned int width, unsigned int height, unsigned char raw0, unsigned char raw1, unsigned char raw2)
	decode JPEG buffer More...

int	decode_jpeg_rgb (unsigned char inBuffer, unsigned long inSize, uint8_t memptr, size_t memsize, int naxis, int w, int *h)
	decode_jpeg_rgb Read jpeg in memory buffer and produce RGB image More...

int	decode_jpeg_gray_raw (unsigned char jpeg_data, int len, int itype, int ctype, unsigned int width, unsigned int height, unsigned char raw0, unsigned char raw1, unsigned char raw2)
	decode JPEG raw gray buffer More...

int	encode_jpeg_raw (unsigned char jpeg_data, int len, int quality, int itype, int ctype, unsigned int width, unsigned int height, unsigned char raw0, unsigned char raw1, unsigned char raw2)
	encode raw JPEG buffer More...

Detailed Description

jpeg_data: buffer with input / output jpeg
len: Length of jpeg buffer
itype: Y4M_ILACE_NONE: Not interlaced
Y4M_ILACE_TOP_FIRST: Interlaced, top-field-first
Y4M_ILACE_BOTTOM_FIRST: Interlaced, bottom-field-first
ctype Chroma format for decompression.

Currently always 420 and hence ignored.
raw0 buffer with input / output raw Y channel
raw1 buffer with input / output raw U/Cb channel
raw2 buffer with input / output raw V/Cr channel
width width of Y channel (width of U/V is width/2)
height height of Y channel (height of U/V is height/2)

Macro Definition Documentation

◆ Y4M_CHROMA_411

#define Y4M_CHROMA_411 5 /** 4:1:1, H cosited */

◆ Y4M_CHROMA_420JPEG

#define Y4M_CHROMA_420JPEG 0 /** 4:2:0, H/V centered, for JPEG/MPEG-1 */

◆ Y4M_CHROMA_420MPEG2

#define Y4M_CHROMA_420MPEG2 1 /** 4:2:0, H cosited, for MPEG-2 */

◆ Y4M_CHROMA_420PALDV

#define Y4M_CHROMA_420PALDV 2 /** 4:2:0, alternating Cb/Cr, for PAL-DV */

◆ Y4M_CHROMA_422

#define Y4M_CHROMA_422 4 /** 4:2:2, H cosited */

◆ Y4M_CHROMA_444

#define Y4M_CHROMA_444 3 /** 4:4:4, no subsampling, phew. */

◆ Y4M_CHROMA_444ALPHA

#define Y4M_CHROMA_444ALPHA 7 /** 4:4:4 with an alpha channel */

◆ Y4M_CHROMA_MONO

#define Y4M_CHROMA_MONO 6 /** luma plane only */

◆ Y4M_ILACE_BOTTOM_FIRST

#define Y4M_ILACE_BOTTOM_FIRST 2 /** interlaced, bottom-field first */

◆ Y4M_ILACE_MIXED

#define Y4M_ILACE_MIXED 3 /** mixed, "refer to frame header" */

◆ Y4M_ILACE_NONE

#define Y4M_ILACE_NONE 0 /** non-interlaced, progressive frame */

◆ Y4M_ILACE_TOP_FIRST

#define Y4M_ILACE_TOP_FIRST 1 /** interlaced, top-field first */

Function Documentation

◆ decode_jpeg_gray_raw()

int decode_jpeg_gray_raw	(	unsigned char *	jpeg_data,
		int	len,
		int	itype,
		int	ctype,
		unsigned int	width,
		unsigned int	height,
		unsigned char *	raw0,
		unsigned char *	raw1,
		unsigned char *	raw2
	)

decode JPEG raw gray buffer

◆ decode_jpeg_raw()

int decode_jpeg_raw	(	unsigned char *	jpeg_data,
		int	len,
		int	itype,
		int	ctype,
		unsigned int	width,
		unsigned int	height,
		unsigned char *	raw0,
		unsigned char *	raw1,
		unsigned char *	raw2
	)

decode JPEG buffer

◆ decode_jpeg_rgb()

int decode_jpeg_rgb	(	unsigned char *	inBuffer,
		unsigned long	inSize,
		uint8_t **	memptr,
		size_t *	memsize,
		int *	naxis,
		int *	w,
		int *	h
	)

decode_jpeg_rgb Read jpeg in memory buffer and produce RGB image

Parameters

inBuffer	pointer to jpeg file in memory
inSize	file of jpeg file in bytes
memptr	pointer to store RGB data. To enhance performance, the memory must be allocated at least byte. memptr = malloc(1) since subsequent calls will use realloc to allocate memory. The caller is responsible for free(*memptr) eventually.
memsize	size of RGB data as determined after jpeg decompression
naxis	1 for mono, 3 for color
w	width of image in pixels
h	height image in pixels

Returns: 0 if decoding sucseeds, -1 otherwise.

◆ encode_jpeg_raw()

int encode_jpeg_raw	(	unsigned char *	jpeg_data,
		int	len,
		int	quality,
		int	itype,
		int	ctype,
		unsigned int	width,
		unsigned int	height,
		unsigned char *	raw0,
		unsigned char *	raw1,
		unsigned char *	raw2
	)

encode raw JPEG buffer

Macros

Functions