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Example for the LPC4088 QSB Base Board
bmp.cpp
- Committer:
- embeddedartists
- Date:
- 2014-04-09
- Revision:
- 3:15f457b3bdbd
- Parent:
- 0:a771927a62fd
File content as of revision 3:15f457b3bdbd:
/* ---------------------------------------------------------------------------- * ATMEL Microcontroller Software Support - ROUSSET - * ---------------------------------------------------------------------------- * Copyright (c) 2006, Atmel Corporation * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * - Redistributions of source code must retain the above copyright notice, * this list of conditions and the disclaiimer below. * * - Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the disclaimer below in the documentation and/or * other materials provided with the distribution. * * Atmel's name may not be used to endorse or promote products derived from * this software without specific prior written permission. * * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ---------------------------------------------------------------------------- */ //------------------------------------------------------------------------------ // Headers //------------------------------------------------------------------------------ #include "mbed.h" #include "bmp.h" //------------------------------------------------------------------------------ // Internal constants //------------------------------------------------------------------------------ /// BMP magic number ('BM'). #define BMP_TYPE 0x4D42 //------------------------------------------------------------------------------ // Internal types //------------------------------------------------------------------------------ struct BMPPaletteEntry { unsigned char b; unsigned char g; unsigned char r; unsigned char filler; }; //------------------------------------------------------------------------------ // Exported functions //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ /// Returns 1 if the header of a BMP file is valid; otherwise returns 0. /// \param file Buffer holding the file to examinate. //------------------------------------------------------------------------------ unsigned char BMP_IsValid(void *file) { return ((struct BMPHeader *) file)->type == BMP_TYPE; } //------------------------------------------------------------------------------ /// Returns the size of a BMP image given at least its header (the file does /// not have to be complete). /// \param file Pointer to the buffer which holds the BMP file. //------------------------------------------------------------------------------ unsigned int BMP_GetFileSize(void *file) { return ((struct BMPHeader *) file)->fileSize; } //------------------------------------------------------------------------------ /// Loads a BMP image located at the given address, decodes it and stores the /// resulting image inside the provided buffer. Image must have the specified /// width & height. /// Returns 0 if the image has been loaded; otherwise returns an error code. /// \param file Buffer which holds the BMP file. /// \param buffer Buffer in which to store the decoded image. /// \param width Buffer width in pixels. /// \param height Buffer height in pixels. /// \param bpp Number of bits per pixels that the buffer stores. //------------------------------------------------------------------------------ unsigned char BMP_Decode( void *file, unsigned char *buffer, unsigned int width, unsigned int height, unsigned char bpp) { struct BMPHeader *header; unsigned int i, j; unsigned char r, g, b; unsigned char *image; // Read header information header = (struct BMPHeader *) file; // Verify that the file is valid if (!BMP_IsValid(file)) { printf("BMP_Decode: File type is not 'BM' (0x%x).\n\r", header->type); return 1; } // Check that parameters match if ((header->compression != 0) || (header->width != width) || (header->height != height)) { printf("BMP_Decode: File format not supported\n\r"); printf(" -> .compression = %d\n\r", header->compression); printf(" -> .width = %d\n\r", header->width); printf(" -> .height = %d\n\r", header->height); printf(" -> .bits = %d\n\r", header->bits); return 2; } // Get image data image = (unsigned char *) ((unsigned int) file + header->offset); // Check that the bpp resolution is supported // Only a 24-bit output & 24- or 8-bit input are supported if (bpp != 24) { printf("BMP_Decode: Output resolution not supported\n\r"); return 3; } else if (header->bits == 24) { // Modified by Embedded Artists. This padding was not handled in the original // implementation. Each row in the Pixel Array is padded to a multiple of 4 bytes in size int rowWidthBytes = width * 3; rowWidthBytes += (rowWidthBytes % 4); // Copy raw data from BMP to buffer (reversing row order) for (i=0; i < height; i++) { #if 1 // Modified by Embedded Artists to convert to 565-format instead of 24 bit int x; for(x=0; x<width; x++) { r = *(unsigned char *)(image + (height - i - 1) * rowWidthBytes + 3*x + 2); g = *(unsigned char *)(image + (height - i - 1) * rowWidthBytes + 3*x + 1); b = *(unsigned char *)(image + (height - i - 1) * rowWidthBytes + 3*x + 0); *(unsigned short *)(buffer + (i * width) * 2 + 2*x) = (((unsigned short)r & 0xF8) << 8) | (((unsigned short)g & 0xFC) << 3) | (((unsigned short)b & 0xF8) >> 3); } #else memcpy(buffer + (i * width) * 3, image + ((height - i - 1) * width) * 3, width * 3); #endif } #if 0 // Swap red and blue for (i=0; i < height; i++) { for (j=0; j < width; j++) { r = buffer[(i * width + j) * 3 + 2]; g = buffer[(i * width + j) * 3 + 1]; b = buffer[(i * width + j) * 3]; buffer[(i * width + j) * 3] = r; buffer[(i * width + j) * 3 + 1] = g; buffer[(i * width + j) * 3 + 2] = b; } } #endif } else if (header->bits == 8) { // Retrieve palette struct BMPPaletteEntry palette[256]; memcpy(palette, (unsigned char *) ((unsigned int) file + sizeof(struct BMPHeader)), header->offset - sizeof(struct BMPHeader)); // Decode image (reversing row order) for (i=0; i < height; i++) { for (j=0; j < width; j++) { r = palette[image[(height - i - 1) * width + j]].r; g = palette[image[(height - i - 1) * width + j]].g; b = palette[image[(height - i - 1) * width + j]].b; buffer[(i * width + j) * 3] = r; buffer[(i * width + j) * 3 + 1] = g; buffer[(i * width + j) * 3 + 2] = b; } } } else { printf("BMP_Decode: Input resolution not supported\n\r"); return 4; } return 0; }