imgdcd_image_util.h

This is a resource based on j2me embedded,if you dont understand,you can connection with me .

/*
 *   
 *
 * Copyright  1990-2006 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 only, as published by the Free Software Foundation. 
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt). 
 * 
 * You should have received a copy of the GNU General Public License
 * version 2 along with this work; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA 
 * 
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions. 
 */

#ifndef _IMGDCD_IMAGE_H_
#define _IMGDCD_IMAGE_H_

#include <midpError.h>
#include <img_errorcodes.h>

/**
 * @file
 * @ingroup lowui_imgdcd
 *
 * @brief Graphics utility api for image decoding
 */

#ifdef __cplusplus
extern "C" {
#endif


/**
 * 16-bit pixel.
 * The color encoding used in pixels is 565, that is,
 * 5+6+5=16 bits for red, green, blue.
 */
typedef unsigned short imgdcd_pixel_type;

/** 8-bit alpha */
typedef unsigned char imgdcd_alpha_type;



/** Type of image */
typedef enum {
    IMGDCD_IMAGE_FORMAT_UNSUPPORTED,
    IMGDCD_IMAGE_FORMAT_PNG,
    IMGDCD_IMAGE_FORMAT_JPEG,
    IMGDCD_IMAGE_FORMAT_RAW,
} imgdcd_image_format;

/** PNG file header */
extern const unsigned char imgdcd_png_header[16];

/** JPEG file header */
extern const unsigned char imgdcd_jpeg_header[4];

/** RAW platform dependent image file header */
extern const unsigned char imgdcd_raw_header[4];

/** PNG image buffer layout */
typedef struct {
    unsigned char header[16]; /**< Must equal imgdcd_png_header */
    unsigned char width[4];   /**< Big-endian intergar */
    unsigned char height[4];  /**< Big-endian intergar */
    unsigned char data[1];    /**< variable length byte array */
} imgdcd_image_buffer_png;

/** JPEG image buffer layout */
typedef struct {
    unsigned char header[4];  /**< Must equal imgdcd_jpeg_header */
    /** Length of data (including these 2 bytes), big-endian. */
    unsigned char length[2];
    unsigned char id[5];      /**< 4A, 46, 49, 46, 00 ("JFIF" string) */
    /**
     * JFIF format revision (often 01, 02).
     * The most significant byte is used for major revisions;
     * the least significant byte for minor revisions.
     */
    unsigned char version[2];
    /**
     * Units used for density:
     *   0 - no units, densityX and densityY specify the pixel aspect ratio;
     *   1 - densityX and densityY are dots per inch;
     *   2 - densityX and densityY are dots per cm.
     */
    unsigned char units;
    unsigned char densityX[2];     /**< Horizontal density (big-endian) */
    unsigned char densityY[2];     /**< Vertical density (big-endian) */
    unsigned char thumbnailWidth;  /**< 0 - no thumbnail */
    unsigned char thumbnailHeight; /**< 0 - no thumbnail */
    /*
     * 3 * thumbnailWidth * thumbnailHeight bytes:
     * 24-bit RGB values for the thumbnail pixels.
     */
} imgdcd_image_buffer_jpeg;

/** RAW image buffer layout */
typedef struct {
    unsigned char header[4];  /**< Must equal imgdcd_raw_header */
    unsigned int width;       /**< Default endian intergar */
    unsigned int height;      /**< Default endian intergar */
    unsigned int hasAlpha;    /**< Default endian intergar */
    unsigned char data[1];    /**< variable length byte array */
} imgdcd_image_buffer_raw;

/**
 * Identify image format from a given image buffer.
 *
 * @param imgBuffer buffer contains the image data
 * @param length    number of bytes of the buffer
 * @param format    return image format
 * @param width     return image width
 * @param height    return image height
 *
 * @return one of error codes:
 *              MIDP_ERROR_NONE,
 *              MIDP_ERROR_UNSUPPORTED
 *              MIDP_ERROR_IMAGE_CORRUPTED
 */
extern MIDP_ERROR imgdcd_image_get_info(unsigned char *imgBuffer,
                                        unsigned int length,
                                        imgdcd_image_format *format,
                                        unsigned int *width,
                                        unsigned int *height);

/**
 * Decodes the given input data into a storage format used by immutable
 * images.  The input data should be a PNG image.
 *
 *  @param srcBuffer input data to be decoded.
 *  @param length length of the input data.
 *  @param creationErrorPtr pointer to the status of the decoding
 *         process. This function sets creationErrorPtr's value.
 */
extern int imgdcd_decode_png(unsigned char* srcBuffer, int length, 
                             int  width, int height,
                             imgdcd_pixel_type *pixelData, 
                             imgdcd_alpha_type *alphaData,
                             img_native_error_codes* creationErrorPtr);
  

/**
 * Decodes the given input data into a storage format used by
 * images.  The input data should be a JPEG image.
 *
 *  @param srcBuffer input data to be decoded.
 *  @param length length of the input data.
 *  @param creationErrorPtr pointer to the status of the decoding
 *         process. This function sets creationErrorPtr's value.
 */
extern void imgdcd_decode_jpeg (unsigned char* srcBuffer, int length,
                                int width, int height,
                                imgdcd_pixel_type *pixelData, 
                                imgdcd_alpha_type *alphaData,
                                img_native_error_codes* creationErrorPtr);



#ifdef __cplusplus
}
#endif

#endif /* _IMGDCD_IMAGE_H_ */