enc_png.c File Reference

Functions for dealing with PNG. More...

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <png.h>
#include "grib2_int.h"

Go to the source code of this file.

Typedefs
typedef struct png_stream	png_stream
	Typedef for PNG stream. More...

Functions
int	enc_png (unsigned char *data, g2int width, g2int height, g2int nbits, unsigned char *pngbuf)
	Encode PNG. More...
void	user_flush_data (png_structp png_ptr)
	Dummy Custom flush function. More...
void	user_write_data (png_structp png_ptr, png_bytep data, png_uint_32 length)
	Custom write function used to that libpng will write to memory location instead of a file on disk. More...

Detailed Description

Functions for dealing with PNG.

Author

Stephen Gilbert

Definition in file enc_png.c.

Typedef Documentation

png_stream

typedef struct png_stream png_stream

Typedef for PNG stream.

Definition at line 1 of file enc_png.c.

Function Documentation

enc_png()

int enc_png	(	unsigned char *	data,
		g2int	width,
		g2int	height,
		g2int	nbits,
		unsigned char *	pngbuf
	)

Encode PNG.

Parameters

data	data.
width	width.
height	height.
nbits	number of bits.
pngbuf	PNG buffer.

Returns

PNG length, or negative number for error.

Author

Stephen Gilbert

Definition at line 75 of file enc_png.c.

References user_flush_data(), and user_write_data().

Referenced by pngpack_int().

user_flush_data()

void user_flush_data

(

png_structp

png_ptr

)

Dummy Custom flush function.

Parameters

png_ptr

Pointer to PNG struct.

Author

Stephen Gilbert

Definition at line 57 of file enc_png.c.

Referenced by enc_png().

user_write_data()

void user_write_data	(	png_structp	png_ptr,
		png_bytep	data,
		png_uint_32	length
	)

Custom write function used to that libpng will write to memory location instead of a file on disk.

Parameters

png_ptr	pointer
data	data
length	length

Author

Stephen Gilbert

Definition at line 37 of file enc_png.c.

Referenced by enc_png().