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分享c语言 实现bmp转pdf 问题
在网上找了份jpeg2pdf的代码， 尝试修改成bmp2pdf， 不过失败了
不知道有没有大侠做过这个 指点一下， 目前改法是直接将jpeg图片换成bmp 然后把需要的宽度高度等信息直接用bmp的替换
不知道有没有大侠做过这个 指点一下， 目前改法是直接将jpeg图片换成bmp 然后把需要的宽度高度等信息直接用bmp的替换
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lanting918 2016-10-12
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有嵌入式适合的bmp转jpeg算法吗？ 这块我同事写了一个 转一副240*200的bmp 到jpeg要花1s多时间 受不了
lanting918 2016-10-12
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将BMP转jpg的方式是可行的 ， 本段代码对jpeg 没问题。
不过我们的设备里面做转换的时候效率不高 我再试试
谢谢
赵4老师 2016-10-12
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嵌入式有GDI+吗？
赵4老师 2016-10-10
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使用GDI+将bmp转jpg再调用jpeg2pdf
Sniper_Pan 2016-10-10
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代码没细看，不过Jpeg和Bmp对图片像素点的编码方式并不相同，简单替换buffer应该会有问题。
你可以试着通过mspaint或者其他工具将bmp先转换成jpeg然后测试下本段代码是否可行。
如可行，则只需做BMP移植，如不可行，则需换别的代码。
lanting918 2016-10-10
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STATUS Jpeg2PDF_AddJpeg(PJPEG2PDF pPDF, UINT32 imgW, UINT32 imgH, UINT32 fileSize, UINT8 *pJpeg, UINT8 isColor, PageOrientation pageOrientation,
double dpiX, double dpiY, ScaleMethod scale, bool cropHeight, bool cropWidth) {
STATUS result = ERROR;
PJPEG2PDF_NODE pNode;
double imgAspect, newImgW, newImgH;
if(pPDF) {
if(pPDF->nodeCount >= MAX_PDF_PAGES) {
logMsg("Add JPEG into PDF Skipped. Reason: Reached Max Page Number (%d) in single PDF.\n", MAX_PDF_PAGES,2,3,4,5,6);
return result;
}
pNode = (PJPEG2PDF_NODE)malloc(sizeof(JPEG2PDF_NODE));
if(pNode) {
UINT32 nChars, currentImageObject;
UINT8 *pFormat, lenStr[256];
pNode->JpegW = imgW;
pNode->JpegH = imgH;
pNode->JpegSize = fileSize;
pNode->pJpeg = (UINT8 *)malloc(pNode->JpegSize);
pNode->pNext = NULL;
if(pNode->pJpeg != NULL) {
bool jpegPortrait, pagePortrait;
double pageWidth, pageHeight; // accounting for page orientation, in PDF units (pixels at PDF_DOT_PER_INCH dpi)
double maxImgWidth, maxImgHeight; // actual values accounting for page orientation, in PDF units
double jpegWidth, jpegHeight; // jpeg dimensions (accounting for dpiX, dpiY, PDF_DOT_PER_INCH), in PDF units
Fit fit;
memcpy(pNode->pJpeg, pJpeg, pNode->JpegSize);
/* Image Object */
Jpeg2PDF_SetXREF(pPDF, INDEX_USE_PPDF, pPDF->currentOffSet, 'n');
currentImageObject = pPDF->pdfObj;
pPDF->currentOffSet += sprintf(pNode->preFormat, "\n%d 0 obj\n<</Subtype/Image/Length 670/Width 248/Height 200/BitsPerComponent 1/ColorSpace/DeviceGray/Filter/JBIG2Decode/Interpolate true/Decode[ 1 0]>>stream\n",
pPDF->pdfObj, ((isColor)? "DeviceRGB" : "DeviceGray"), pNode->JpegW, pNode->JpegH, pNode->JpegSize);
pPDF->currentOffSet += pNode->JpegSize;
pFormat = pNode->pstFormat;
nChars = sprintf(pFormat, "\nendstream\nendobj\n");
pPDF->currentOffSet += nChars; pFormat += nChars;
pPDF->pdfObj++;
/* determine scale of the image keeping aspect ratio */
jpegWidth=((double)pNode->JpegW)*PDF_DOT_PER_INCH/dpiX;
jpegHeight=((double)pNode->JpegH)*PDF_DOT_PER_INCH/dpiY;
imgAspect=jpegWidth/jpegHeight;
if(JPEG2PDF_DEBUG) logMsg("imgAspect = %f %d %d\n", imgAspect, pNode->JpegW, pNode->JpegH, 3,4,5,6);
// Determine page orientation:
jpegPortrait=(jpegWidth <= jpegHeight);
if(pageOrientation==PageOrientationAuto){
if(scale==ScaleNone && jpegWidth<=pPDF->maxImgW && jpegHeight<=pPDF->maxImgH){ // image already fits into available area, don't rotate the page
pagePortrait=true; // assuming portrait orientation the most convenient for most users
}else{
pagePortrait=jpegPortrait;
if((pPDF->maxImgW < pPDF->maxImgH) ^ (pPDF->pageW < pPDF->pageH)){ // very rare case: page orientation is opposite to available area orientation (it's possible with differently sized margins)
pagePortrait=!pagePortrait;
}
}
}else{
pagePortrait=(pageOrientation==Portrait) ? true : false;
}
maxImgWidth=pagePortrait ? pPDF->maxImgW : pPDF->maxImgH;
maxImgHeight=pagePortrait ? pPDF->maxImgH : pPDF->maxImgW;
// Determine scaling method:
if(scale==ScaleFit || (scale==ScaleReduce && (jpegWidth>maxImgWidth || jpegHeight>maxImgHeight))){ // fit jpeg to available area
if(maxImgWidth/maxImgHeight > imgAspect){ // available area aspect is wider than jpeg aspect
fit=FitHeight;
}else{ // jpeg aspect is wider than available area aspect
fit=FitWidth;
}
}else if(scale==ScaleFitWidth || (scale==ScaleReduceWidth && jpegWidth>maxImgWidth)){
fit=FitWidth;
}else if(scale==ScaleFitHeight || (scale==ScaleReduceHeight && jpegHeight>maxImgHeight)){
fit=FitHeight;
}else{ // don't fit, keep original dpi
fit=FitNone;
}
// Scale image:
if(fit==FitWidth){
newImgW=maxImgWidth;
newImgH=maxImgWidth/imgAspect;
}else if(fit==FitHeight){
newImgW=maxImgHeight*imgAspect;
newImgH=maxImgHeight;
}else{//fit==FitNone
newImgW=jpegWidth;
newImgH=jpegHeight;
}
// Set paper size from image size (possibly fitted/reduced to specific paper size) or properly rotate the page:
pageWidth=cropWidth ? (newImgW+pPDF->margin) : (pagePortrait ? pPDF->pageW : pPDF->pageH);
pageHeight=cropHeight ? (newImgH+pPDF->margin) : (pagePortrait ? pPDF->pageH : pPDF->pageW);
/* Page Object */
Jpeg2PDF_SetXREF(pPDF, INDEX_USE_PPDF, pPDF->currentOffSet, 'n');
pNode->PageObj = pPDF->pdfObj;
nChars = sprintf(pFormat, "%d 0 obj\n<</Type/Page/Parent 1 0 R/MediaBox[0 0 %.2f %.2f]/Contents %d 0 R/Resources %d 0 R>>\nendobj\n",
pPDF->pdfObj, pageWidth, pageHeight, pPDF->pdfObj+1, pPDF->pdfObj + 3);
pPDF->currentOffSet += nChars; pFormat += nChars;
pPDF->pdfObj++;
/* Contents Object in Page Object */
Jpeg2PDF_SetXREF(pPDF, INDEX_USE_PPDF, pPDF->currentOffSet, 'n');
sprintf(lenStr, "q\n1 0 0 1 %.2f %.2f cm\n%.2f 0 0 %.2f 0 0 cm\n/I%d Do\nQ\n",
(pageWidth-newImgW)/2, (pageHeight-newImgH)/2, newImgW , newImgH , pPDF->imgObj); // center image
nChars = sprintf(pFormat, "%d 0 obj\n<</Length %d 0 R>>stream\n%sendstream\nendobj\n",
pPDF->pdfObj, pPDF->pdfObj+1, lenStr);
pPDF->currentOffSet += nChars; pFormat += nChars;
pPDF->pdfObj++;
/* Length Object in Contents Object */
Jpeg2PDF_SetXREF(pPDF, INDEX_USE_PPDF, pPDF->currentOffSet, 'n');
nChars = sprintf(pFormat, "%d 0 obj\n%ld\nendobj\n", pPDF->pdfObj, strlen(lenStr));
pPDF->currentOffSet += nChars; pFormat += nChars;
pPDF->pdfObj++;
/* Resources Object in Page Object */
Jpeg2PDF_SetXREF(pPDF, INDEX_USE_PPDF, pPDF->currentOffSet, 'n');
nChars = sprintf(pFormat, "%d 0 obj\n<</ProcSet[/PDF/%s]/XObject<</I%d %d 0 R>>>>\nendobj\n",
pPDF->pdfObj, ((isColor)? "ImageC" : "ImageB"), pPDF->imgObj, currentImageObject);
pPDF->currentOffSet += nChars; pFormat += nChars;
pPDF->pdfObj++;
pPDF->imgObj++;
/* Update the Link List */
pPDF->nodeCount++;
if(1 == pPDF->nodeCount) {
pPDF->pFirstNode = pNode;
} else {
pPDF->pLastNode->pNext = pNode;
}
pPDF->pLastNode = pNode;
result = OK;
} /* pNode->pJpeg allocated OK */
} /* pNode is valid */
} /* pPDF is valid */
return result;
}
目前直接把这个函数的jpeg buf用bmp buf替换 生成的pdf看不到图
