bmp_v1

bmp.c

@@ -0,0 +1,175 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <inttypes.h>
+typedef unsigned char uch;
+
+// ™n°¸½Y˜‹
+#pragma pack(2)
+struct BmpFileHeader {
+    uint16_t bfTybe;
+    uint32_t bfSize;
+    uint16_t bfReserved1;
+    uint16_t bfReserved2;
+    uint32_t bfOffBits;
+};
+struct BmpInfoHeader {
+    uint32_t biSize;
+    uint32_t biWidth;
+    uint32_t biHeight;
+    uint16_t biPlanes; // 1=defeaul, 0=custom
+    uint16_t biBitCount;
+    uint32_t biCompression;
+    uint32_t biSizeImage;
+    uint32_t biXPelsPerMeter; // 72dpi=2835, 96dpi=3780
+    uint32_t biYPelsPerMeter; // 120dpi=4724, 300dpi=11811
+    uint32_t biClrUsed;
+    uint32_t biClrImportant;
+};
+#pragma pack()
+
+
+void bmpWrite(const char* name, const uch* raw_img, uint32_t width, uint32_t height, uint16_t bits)
+{
+    if(!(name && raw_img)) {
+        perror("Error bmpWrite.");
+        return;
+    }
+    // ™n°¸ÙYÓ<59>
+    struct BmpFileHeader file_h = {
+        .bfTybe=0x4d42,
+        .bfReserved1=0,
+        .bfReserved2=0,
+        .bfOffBits=54,
+    };
+    file_h.bfSize = file_h.bfOffBits + width*height * bits/8;
+    if(bits==8) {file_h.bfSize+= 1024, file_h.bfOffBits+= 1024;}
+    // ˆDƬÙYÓ<59>
+    struct BmpInfoHeader info_h = {
+        .biSize=40,
+        .biPlanes=1,
+        .biCompression=0,
+        .biXPelsPerMeter=0,
+        .biYPelsPerMeter=0,
+        .biClrUsed=0,
+        .biClrImportant=0,
+    };
+    info_h.biWidth = width;
+    info_h.biHeight = height;
+    info_h.biBitCount = bits;
+    info_h.biSizeImage = width*height * bits/8;
+    if(bits == 8) {info_h.biClrUsed=256;}
+    // Œ‘Èë™nî^
+    FILE *pFile = NULL;
+    // pFile = fopen(name,"wb+");
+    fopen_s(&pFile, name,"wb+");
+    if(!pFile) {
+        perror("Error opening file.");
+        return;
+    }
+    fwrite((char*)&file_h, sizeof(char), sizeof(file_h), pFile);
+    fwrite((char*)&info_h, sizeof(char), sizeof(info_h), pFile);
+    // Œ‘Õ{É«±P
+    if(bits == 8) {
+        for(unsigned i = 0; i < 256; ++i) {
+            uch c = i;
+            fwrite((char*)&c, sizeof(char), sizeof(uch), pFile);
+            fwrite((char*)&c, sizeof(char), sizeof(uch), pFile);
+            fwrite((char*)&c, sizeof(char), sizeof(uch), pFile);
+            fwrite("", sizeof(char), sizeof(uch), pFile);
+        }
+    }
+    // Œ‘ÈëˆDƬÙYÓ<59>
+    size_t alig = ((width*bits/8)*3) % 4;
+    for(int j = height-1; j >= 0; --j) {
+        for(unsigned i = 0; i < width; ++i) {
+            uint32_t idx = j*width +i;
+            if(bits == 24) { // RGBˆDƬ
+                fwrite((char*)&raw_img[idx*3 +2], sizeof(char), sizeof(uch), pFile);
+                fwrite((char*)&raw_img[idx*3 +1], sizeof(char), sizeof(uch), pFile);
+                fwrite((char*)&raw_img[idx*3 +0], sizeof(char), sizeof(uch), pFile);
+            }
+            else if(bits == 8) { // »ÒëAˆD
+                fwrite((char*)&raw_img[idx], sizeof(char), sizeof(uch), pFile);
+            }
+        }
+        // Œ¦ýR4byte
+        for(size_t i = 0; i < alig; ++i) {
+            fwrite("", sizeof(char), sizeof(uch), pFile);
+        }
+    }
+    fclose(pFile);
+}
+void bmpRead(const char* name, uch** raw_img, uint32_t* width, uint32_t* height, uint16_t* bits)
+{
+    if(!(name && raw_img && width && height && bits)) {
+        perror("Error bmpRead.");
+        return;
+    }
+    // ™n°¸ÙYÓ<59>
+    struct BmpFileHeader file_h;
+    // ˆDƬÙYÓ<59>
+    struct BmpInfoHeader info_h;
+    // ×xÈ¡™nî^
+    FILE *pFile = NULL;
+    // pFile = fopen(name, "rb+");
+    fopen_s(&pFile, name, "rb+");
+    if(!pFile) {
+        perror("Error opening file.");
+        return;
+    }
+    fread((char*)&file_h, sizeof(char), sizeof(file_h), pFile);
+    fread((char*)&info_h, sizeof(char), sizeof(info_h), pFile);
+    // ×xÈ¡éLŒ’
+    *width = info_h.biWidth;
+    *height = info_h.biHeight;
+    *bits = info_h.biBitCount;
+    size_t ImgSize = ((size_t)*width) * ((size_t)*height) * 3;
+    *raw_img = (uch*)calloc(ImgSize, sizeof(uch));
+    // ×xÈ¡×xƬÙYÓ<59>ÞDRAW™nÙYÓ<59>
+    fseek(pFile, file_h.bfOffBits, SEEK_SET);
+    size_t alig = ((info_h.biWidth*info_h.biBitCount/8)*3) % 4;
+    for(int j = *height-1; j >= 0; --j) {
+        for(unsigned i = 0; i < *width; ++i) {
+            uint32_t idx = j*(*width)+i;
+            if(*bits == 24) { // RGBˆDƬ
+                fread((char*)&(*raw_img)[idx*3 +2], 
+                    sizeof(char), sizeof(uch), pFile);
+                fread((char*)&(*raw_img)[idx*3 +1], 
+                    sizeof(char), sizeof(uch), pFile);
+                fread((char*)&(*raw_img)[idx*3 +0], 
+                    sizeof(char), sizeof(uch), pFile);
+            } else if(*bits == 8) { // »ÒëAˆD
+                fread((char*)&(*raw_img)[idx], 
+                    sizeof(char), sizeof(uch), pFile);
+            }
+        }
+        fseek(pFile , (long)alig , SEEK_CUR);
+    }
+    fclose(pFile);
+}
+
+// ˆDÏñ½Y˜‹
+typedef struct Imgraw {
+    uint32_t width, height;
+    uint16_t bits;
+    uch* data;
+} Imgraw;
+void Imgraw_Read(const Imgraw* _this, const char* name) {
+    const Imgraw* p = _this;
+    bmpRead(name, &p->data, &p->width, &p->height, &p->bits);
+}
+void Imgraw_Writ(const Imgraw* _this, const char* name) {
+    const Imgraw* p = _this;
+    bmpWrite(name, p->data, p->width, p->height, p->bits);
+}
+/*==============================================================*/
+int main(int argc, char const *argv[]) {
+    // ½¨˜‹
+    Imgraw img = {0, 0, 0, NULL};
+    // ×xˆD
+    Imgraw_Read(&img, "./input/bw2x1.bmp");
+    // Œ‘ˆD
+    Imgraw_Writ(&img, "./output/bw2x1(output).bmp");
+    return 0;
+}
+/*==============================================================*/

bmp.h

@@ -0,0 +1,50 @@
+// BMP-related data types based on Microsoft's own
+
+#include <stdint.h>
+
+// aliases for C/C++ primitive data types
+// https://msdn.microsoft.com/en-us/library/cc230309.aspx
+typedef uint8_t  BYTE;
+typedef uint32_t DWORD;
+typedef int32_t  LONG;
+typedef uint16_t WORD;
+
+// information about the type, size, and layout of a file
+// https://msdn.microsoft.com/en-us/library/dd183374(v=vs.85).aspx
+typedef struct
+{
+    WORD bfType;
+    DWORD bfSize;
+    WORD bfReserved1;
+    WORD bfReserved2;
+    DWORD bfOffBits;
+} __attribute__((__packed__))
+BITMAPFILEHEADER;
+
+// information about the dimensions and color format
+// https://msdn.microsoft.com/en-us/library/dd183376(v=vs.85).aspx
+typedef struct
+{
+    DWORD biSize;
+    LONG biWidth;
+    LONG biHeight;
+    WORD biPlanes;
+    WORD biBitCount;
+    DWORD biCompression;
+    DWORD biSizeImage;
+    LONG biXPelsPerMeter;
+    LONG biYPelsPerMeter;
+    DWORD biClrUsed;
+    DWORD biClrImportant;
+} __attribute__((__packed__))
+BITMAPINFOHEADER;
+
+// relative intensities of red, green, and blue
+// https://msdn.microsoft.com/en-us/library/dd162939(v=vs.85).aspx
+typedef struct
+{
+    BYTE rgbtBlue;
+    BYTE rgbtGreen;
+    BYTE rgbtRed;
+} __attribute__((__packed__))
+RGBTRIPLE;