/*------------------------------------------------------------------------------------------------------------
* ビットマップファイルを書き出す
*
* path: 書き出すビットマップファイル
*/
void Bitmap::writeFile(const char *path) const
{
FILE *ofp = fopen(path, "wb");
if (ofp == 0) {
perror("fopen");
fprintf(stderr, "file: %s\n", path);
throw MyError("bitmap file open failed", __FUNCTION__);
}
writeFileHeader(ofp);
writeInfoHeader(ofp);
writeBitmapData(ofp);
fclose(ofp);
}
void BitmapWriter::writeBitmap(Bitmap & bitmap, const char * filePath)
{
FILE * file = fopen(filePath, "wb");
writeFileHeader(bitmap.fileheader, file);
writeInfoHeader(bitmap.infoheader, file);
byte zero = 0;
for (int i = 0; i < bitmap.height; i++) {
for (int j = 0; j < bitmap.width; j++)
writePixel(bitmap.get(j, i), file);
for (int j = 0; j < bitmap.paddingZeros; j++)
fwrite(&zero, sizeof(byte), 1, file);
}
fclose(file);
}
int cropImage(FILE* inFile, struct bmpFileHeader* fileHead,
struct bmpInfoHeader* infoHead, char* outFileName, int cropWidth,
int cropHeight, int cropStart[])
{
// check that cropping parameters make sense
if (((cropWidth + cropStart[0]) > infoHead->width) ||
((cropHeight + cropStart[1]) > infoHead->height))
{
fprintf(stderr, "Cropping parameters incorrect.\n");
return EXIT_FAILURE;
}
// open file for writing
FILE *outFile = fopen(outFileName, "w+");
// check that file opened okay
if (outFile == NULL)
{
fprintf(stderr, "Unable to open file: %s for writing.\n", outFileName);
return EXIT_FAILURE;
}
// store old width/height for use in loop
LONG oldWidth = infoHead->width;
LONG oldHeight = infoHead->height;
// calculate padding used in old image
int oldPadding = (4 - (oldWidth*sizeof(struct pixel) % 4)) % 4;
// calculate padding to be used in new image
int newPadding = (4 - (cropWidth*sizeof(struct pixel) % 4)) % 4;
// new image size
infoHead->imageSize = (cropWidth*sizeof(struct pixel) +
newPadding)*cropHeight;
// file size
fileHead->fileSize = sizeof(struct bmpFileHeader) +
sizeof(struct bmpInfoHeader) + infoHead->imageSize;
// new dimensions
infoHead->width = cropWidth;
infoHead->height = cropHeight;
// write the headers to the output file, checking for errors
if (writeFileHeader(fileHead, outFile) != 0)
{
fprintf(stderr, "Unable to write file header.\n");
return EXIT_FAILURE;
}
if (writeInfoHeader(infoHead, outFile) != 0)
{
fprintf(stderr, "Unable to write info header.\n");
return EXIT_FAILURE;
}
// to store pixel being worked on
struct pixel* curPixel = NULL;
// run through old pixels, discarding those which are to be cropped
// and writing the rest to file
for (int i = 0; i < oldHeight; i++)
{
// only run through line if we're out of region to be cropped
if (!(i < (oldHeight - cropStart[1] - cropHeight) ||
i > (oldHeight - cropStart[1])))
{
for (int j = 0; j < oldWidth; j++)
{
// only write to file if not in cropped region
if (!(j < cropStart[0] || j > cropStart[0] + cropWidth))
{
// read in the current pixel
curPixel = getPixel(inFile);
// make sure read worked
if (curPixel == NULL)
{
fprintf(stderr, "Unable to read pixel.\n");
return EXIT_FAILURE;
}
// write current pixel, checking for error
if (writePixel(curPixel, outFile) != EXIT_SUCCESS)
{
fprintf(stderr, "Unable to write pixel.\n");
return EXIT_FAILURE;
}
}
else
{
// move old file on by a pixel
fseek(inFile, sizeof(struct pixel), SEEK_CUR);
}
}
}
else
{
// move old file on by width + padding
fseek(inFile, oldWidth*sizeof(struct pixel) + oldPadding, SEEK_CUR);
}
// move old file on by padding
fseek(inFile, oldPadding, SEEK_CUR);
// add padding to new file
for (int k = 0; k < newPadding; k++)
{
fputc(0x00, outFile);
}
}
// free memory allocated to current pixel storage
free(curPixel);
// close the output file, checking for error
if (fclose(outFile) != 0)
{
fprintf(stderr, "Unable to close output file: %s.\n", outFileName);
return EXIT_FAILURE;
}
// if program gets to here, everything is okay
return EXIT_SUCCESS;
}
/*
Applies a threshold filter to a BMP file and writes the result to another.
Takes care of opening and closing the output file.
*/
int applyThreshold(FILE* inFile, struct bmpFileHeader* fileHead,
struct bmpInfoHeader* infoHead, char* outFileName, float threshold)
{
// check that threshold value is in range
if (threshold < 0.0 || threshold > 1.0)
{
fprintf(stderr, "Threshold value not in range.\n");
return EXIT_FAILURE;
}
// open file for writing
FILE *outFile = fopen(outFileName, "w+");
// check that file opened okay
if (outFile == NULL)
{
fprintf(stderr, "Unable to open file: %s for writing.\n", outFileName);
return EXIT_FAILURE;
}
// write the headers to the output file, checking for errors
if (writeFileHeader(fileHead, outFile) != 0)
{
fprintf(stderr, "Unable to write file header.\n");
return EXIT_FAILURE;
}
if (writeInfoHeader(infoHead, outFile) != 0)
{
fprintf(stderr, "Unable to write info header.\n");
return EXIT_FAILURE;
}
// calculate amount of padding added to width
int padding = (4 - (infoHead->width*3 % 4)) % 4;
// to store pixel being worked on
struct pixel* curPixel = NULL;
// run through pixels, modifying and saving them to out file
for (int i = 0; i < infoHead->height; i++)
{
for (int j = 0; j < infoHead->width; j++)
{
// get a pixel
curPixel = getPixel(inFile);
// make sure we actually got a pixel
if (curPixel == NULL)
{
fprintf(stderr, "Unable to get pixel.\n");
return EXIT_FAILURE;
}
double maxPixelValue = pow(2, infoHead->colourDepth/3) - 1;
// calculate individual intensity values for each colour
double redIntensity = (curPixel->red)/maxPixelValue;
double greenIntensity = (curPixel->green)/maxPixelValue;
double blueIntensity = (curPixel->blue)/maxPixelValue;
// determine if pixel above thresh, make it black/white accordingly
if ((redIntensity + greenIntensity + blueIntensity)/3.0 > threshold)
{
const uint32_t white = 0xFFFFFF;
// write pixel, checking for error
if (fwrite(&white, 3, 1, outFile) != 1)
{
fprintf(stderr, "Unable to write white pixel to file.\n");
return EXIT_FAILURE;
}
}
else
{
const uint32_t black = 0x000000;
// write pixel, checking for error
if(fwrite(&black, 3, 1, outFile) != 1)
{
fprintf(stderr, "Unable to write black pixel to file.\n");
return EXIT_FAILURE;
}
}
}
// move in-file on by padding amount
fseek(inFile, padding, SEEK_CUR);
// add padding to out-file
for (int k = 0; k < padding; k++)
{
fputc(0x00, outFile);
}
}
// free memory allocated to pixel storage
free(curPixel);
// close the output file, checking for error
if (fclose(outFile) != 0)
{
fprintf(stderr, "Unable to close output file: %s.\n", outFileName);
return EXIT_FAILURE;
}
// if program gets to here, everything is okay
return EXIT_SUCCESS;
}
