Image.cpp

00001 
00002 #include "mbed.h"
00003 #include "Image.h"
00004 
00005 #include "bmp.h"
00006 #include "lodepng.h"
00007 
00008 int Image::decode(const unsigned char* pDataIn, unsigned int sizeIn, ImageData_t* pDataOut)
00009 {
00010   Image::Type type = imageType(pDataIn, sizeIn);
00011   int result = -1;
00012   switch (type)
00013   {
00014     case BMP:
00015     {
00016       struct BMPHeader* hdr = (struct BMPHeader *) pDataIn;
00017       pDataOut->pixels = (uint16_t*)malloc(hdr->width * hdr->height * 2);
00018       if (pDataOut->pixels != NULL)
00019       {
00020         unsigned char error = BMP_Decode((void*)pDataIn, (unsigned char*)pDataOut->pixels, hdr->width, hdr->height, 24);
00021         if (error == 0)
00022         {
00023           pDataOut->width = hdr->width;
00024           pDataOut->height = hdr->height;
00025           return 0;
00026         }
00027         free(pDataOut->pixels);
00028       }
00029     }
00030     break;
00031       
00032     case PNG:
00033     {
00034       unsigned char* pTmp;
00035       unsigned error = lodepng_decode24(&pTmp, &pDataOut->width, &pDataOut->height, pDataIn, sizeIn);
00036       if (error == 0)
00037       {
00038         int x, y;
00039         uint16_t* pConverted;
00040         uint8_t r;
00041         uint8_t g;
00042         uint8_t b;
00043         int off = 0;
00044     
00045         pDataOut->pixels = (uint16_t*)malloc(pDataOut->width * pDataOut->height * 2);
00046         if (pDataOut->pixels != NULL)
00047         {
00048             pConverted = pDataOut->pixels;
00049         
00050             for (y = 0; y < pDataOut->height; y++) {
00051               for (x = 0; x < pDataOut->width; x++) {
00052                 r = pTmp[off    ];
00053                 g = pTmp[off + 1];
00054                 b = pTmp[off + 2];
00055                 *pConverted = (((unsigned short)r & 0xF8) << 8) |
00056                                (((unsigned short)g & 0xFC) << 3) |
00057                                (((unsigned short)b & 0xF8) >> 3);
00058                 pConverted++;
00059                 off += 3;
00060               }
00061             }
00062         }
00063         free(pTmp);
00064         return 0;
00065       }
00066     }
00067     break;
00068     
00069     default:
00070       break;
00071   }
00072   
00073   pDataOut->pixels = NULL;
00074   pDataOut->width = 0;
00075   pDataOut->height = 0;
00076   return result;
00077 }
00078 
00079 Image::Type Image::imageType(const unsigned char* pDataIn, unsigned int sizeIn)
00080 {
00081   if (sizeIn > 4)
00082   {
00083     if (pDataIn[0] == 0x89 && pDataIn[1] == 'P' && pDataIn[2] == 'N' && pDataIn[3] == 'G')
00084     {
00085       return PNG;
00086     }
00087   }
00088   if (BMP_IsValid((void*)pDataIn))
00089   {
00090     return BMP;
00091   }
00092   return UNKNOWN;
00093 }
00094 
00095 
00096