图片转PDF的实现方法

[转载自]http://blog.csdn.net/yiyaaixuexi/article/details/8209188

Quartz 2D概述

Quartz 2D是Core Grapgics下的2D绘图引擎，适用于iOS和Mac OS X。 它具有强大的绘图功能，提供视角效果渲染，反锯齿渲染，颜色管理，绘制PDF等等。

开发者无需考虑不同设备不同分别率的显示效果，因为这一切适配操作Quartz 全都自己包了。

具体Quartz可以做些什么，下图给出了最佳答案：

图片转PDF的工具类

利用Quartz 2D将图片数据转换成图片不失真的PDF，方法我已经封装好：

（PDF部分属性未列出，如果有额外需要，需要另行提出赋值）

//
//  WQPDFManager.h
//  wqphototopdf
//
//  Created by Wu Qian on 12-10-22.
//
//

#import <Foundation/Foundation.h>

@interface WQPDFManager : NSObject

/**
 *  @brief  创建PDF文件
 *
 *  @param  imgData         NSData型   照片数据
 *  @param  destFileName    NSString型 生成的PDF文件名
 *  @param  pw              NSString型 要设定的密码
 */
+ (void)WQCreatePDFFileWithSrc:(NSData *)imgData
                    toDestFile:(NSString *)destFileName
                  withPassword:(NSString *)pw;


/**
 *  @brief  抛出pdf文件存放地址
 *
 *  @param  filename    NSString型 文件名
 *
 *  @return NSString型 地址
 */
+ (NSString *)pdfDestPath:(NSString *)filename;

@end

 

//
//  WQPDFManager.m
//  wqphototopdf
//
//  Created by Wu Qian on 12-10-22.
//
//

#import "WQPDFManager.h"
#import "WQPathUtilities.h"

@implementation WQPDFManager

void WQDrawContent(CGContextRef myContext,
                   CFDataRef data,
                   CGRect rect)
{
    CGDataProviderRef dataProvider = CGDataProviderCreateWithCFData(data);
    CGImageRef image = CGImageCreateWithJPEGDataProvider(dataProvider,
                                                         NULL,
                                                         NO,
                                                         kCGRenderingIntentDefault);
    CGContextDrawImage(myContext, rect, image);

    CGDataProviderRelease(dataProvider);
    CGImageRelease(image);
}

void MyCreatePDFFile (CFDataRef data,
                      CGRect pageRect,
                      const char *filepath,
                      CFStringRef password)
{
    CGContextRef pdfContext;
    CFStringRef path;
    CFURLRef url;
    CFDataRef boxData = NULL;
    CFMutableDictionaryRef myDictionary = NULL;
    CFMutableDictionaryRef pageDictionary = NULL;

    path = CFStringCreateWithCString (NULL, filepath,
                                      kCFStringEncodingUTF8);
    url = CFURLCreateWithFileSystemPath (NULL, path,
                                         kCFURLPOSIXPathStyle, 0);
    CFRelease (path);
    myDictionary = CFDictionaryCreateMutable(NULL,
                                             0,
                                             &kCFTypeDictionaryKeyCallBacks,
                                             &kCFTypeDictionaryValueCallBacks);
    CFDictionarySetValue(myDictionary,
                         kCGPDFContextTitle,
                         CFSTR("Photo from iPrivate Album"));
    CFDictionarySetValue(myDictionary,
                         kCGPDFContextCreator,
                         CFSTR("iPrivate Album"));
    if (password) {
        CFDictionarySetValue(myDictionary, kCGPDFContextUserPassword, password);
        CFDictionarySetValue(myDictionary, kCGPDFContextOwnerPassword, password);
    }

    pdfContext = CGPDFContextCreateWithURL (url, &pageRect, myDictionary);
    CFRelease(myDictionary);
    CFRelease(url);
    pageDictionary = CFDictionaryCreateMutable(NULL,
                                               0,
                                               &kCFTypeDictionaryKeyCallBacks,
                                               &kCFTypeDictionaryValueCallBacks);
    boxData = CFDataCreate(NULL,(const UInt8 *)&pageRect, sizeof (CGRect));
    CFDictionarySetValue(pageDictionary, kCGPDFContextMediaBox, boxData);
    CGPDFContextBeginPage (pdfContext, pageDictionary);
    WQDrawContent(pdfContext,data,pageRect);
    CGPDFContextEndPage (pdfContext);

    CGContextRelease (pdfContext);
    CFRelease(pageDictionary);
    CFRelease(boxData);
}

+ (NSString *)pdfDestPath:(NSString *)filename
{
    return [[WQPathUtilities tmpDirectory]stringByAppendingPathComponent:filename];
}

+ (void)WQCreatePDFFileWithSrc:(NSData *)imgData
                    toDestFile:(NSString *)destFileName
                  withPassword:(NSString *)pw
{
    NSString *fileFullPath = [self pdfDestPath:destFileName];
    const char *path = [fileFullPath UTF8String];
    CFDataRef data = (__bridge CFDataRef)imgData;
    UIImage *image = [UIImage imageWithData:imgData];
    CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
    CFStringRef password = (__bridge CFStringRef)pw;

    MyCreatePDFFile(data,rect, path, password);
}
@end

调用方法

NSData *data = [NSData dataWithContentsOfFile:your_image_path];
NSString *pdfname = @"photoToPDF.pdf";
[WQPDFManager WQCreatePDFFileWithSrc:data toDestFile:pdfname withPassword:nil];

如果需要创建带密码保护的PDF，第三个参数传入密码即可。

 

 

效果图

以 【私人相册】 中的截图示意一下...

将照片转换为密码保护的PDF，并发送EMail ，接收者需键入密码才可查看照片：