Merge pull request #3436 from dreampiggy/bugfix/ios16_pdf_use_coregraphics

Use CoreGraphics to decode PDF instead of ImageIO to solve iOS 16's issue

SDWebImage/Core/SDImageIOAnimatedCoder.m

@@ -18,8 +18,6 @@
 #import <ImageIO/ImageIO.h>
 #import <CoreServices/CoreServices.h>
 
-// Specify DPI for vector format in CGImageSource, like PDF
-static NSString * kSDCGImageSourceRasterizationDPI = @"kCGImageSourceRasterizationDPI";
 // Specify File Size for lossy format encoding, like JPEG
 static NSString * kSDCGImageDestinationRequestedFileSize = @"kCGImageDestinationRequestedFileSize";
 
@@ -568,6 +566,12 @@ static CGImageRef __nullable SDCGImageCreateCopy(CGImageRef cg_nullable image) {
         return nil;
     }
     NSMutableDictionary *properties = [NSMutableDictionary dictionary];
+#if SD_UIKIT || SD_WATCH
+    CGImagePropertyOrientation exifOrientation = [SDImageCoderHelper exifOrientationFromImageOrientation:image.imageOrientation];
+#else
+    CGImagePropertyOrientation exifOrientation = kCGImagePropertyOrientationUp;
+#endif
+    properties[(__bridge NSString *)kCGImagePropertyOrientation] = @(exifOrientation);
     // Encoding Options
     double compressionQuality = 1;
     if (options[SDImageCoderEncodeCompressionQuality]) {

SDWebImage/Core/SDImageIOCoder.m

@@ -10,13 +10,12 @@
 #import "SDImageCoderHelper.h"
 #import "NSImage+Compatibility.h"
 #import "UIImage+Metadata.h"
+#import "SDImageGraphics.h"
 #import "SDImageIOAnimatedCoderInternal.h"
 
 #import <ImageIO/ImageIO.h>
 #import <CoreServices/CoreServices.h>
 
-// Specify DPI for vector format in CGImageSource, like PDF
-static NSString * kSDCGImageSourceRasterizationDPI = @"kCGImageSourceRasterizationDPI";
 // Specify File Size for lossy format encoding, like JPEG
 static NSString * kSDCGImageDestinationRequestedFileSize = @"kCGImageDestinationRequestedFileSize";
 
@@ -57,29 +56,65 @@ static NSString * kSDCGImageDestinationRequestedFileSize = @"kCGImageDestination
     return coder;
 }
 
-#pragma mark - Utils
+#pragma mark - Bitmap PDF representation
-+ (CGRect)boxRectFromPDFFData:(nonnull NSData *)data {
++ (UIImage *)createBitmapPDFWithData:(nonnull NSData *)data pageNumber:(NSUInteger)pageNumber targetSize:(CGSize)targetSize preserveAspectRatio:(BOOL)preserveAspectRatio {
+    NSParameterAssert(data);
+    UIImage *image;
+    
     CGDataProviderRef provider = CGDataProviderCreateWithCFData((__bridge CFDataRef)data);
     if (!provider) {
-        return CGRectZero;
+        return nil;
     }
     CGPDFDocumentRef document = CGPDFDocumentCreateWithProvider(provider);
     CGDataProviderRelease(provider);
     if (!document) {
-        return CGRectZero;
+        return nil;
     }
     
     // `CGPDFDocumentGetPage` page number is 1-indexed.
-    CGPDFPageRef page = CGPDFDocumentGetPage(document, 1);
+    CGPDFPageRef page = CGPDFDocumentGetPage(document, pageNumber + 1);
     if (!page) {
         CGPDFDocumentRelease(document);
-        return CGRectZero;
+        return nil;
     }
     
-    CGRect boxRect = CGPDFPageGetBoxRect(page, kCGPDFMediaBox);
+    CGPDFBox box = kCGPDFMediaBox;
+    CGRect rect = CGPDFPageGetBoxRect(page, box);
+    CGRect targetRect = rect;
+    if (!CGSizeEqualToSize(targetSize, CGSizeZero)) {
+        targetRect = CGRectMake(0, 0, targetSize.width, targetSize.height);
+    }
+    
+    CGFloat xRatio = targetRect.size.width / rect.size.width;
+    CGFloat yRatio = targetRect.size.height / rect.size.height;
+    CGFloat xScale = preserveAspectRatio ? MIN(xRatio, yRatio) : xRatio;
+    CGFloat yScale = preserveAspectRatio ? MIN(xRatio, yRatio) : yRatio;
+    
+    // `CGPDFPageGetDrawingTransform` will only scale down, but not scale up, so we need calculate the actual scale again
+    CGRect drawRect = CGRectMake( 0, 0, targetRect.size.width / xScale, targetRect.size.height / yScale);
+    CGAffineTransform scaleTransform = CGAffineTransformMakeScale(xScale, yScale);
+    CGAffineTransform transform = CGPDFPageGetDrawingTransform(page, box, drawRect, 0, preserveAspectRatio);
+    
+    SDGraphicsBeginImageContextWithOptions(targetRect.size, NO, 0);
+    CGContextRef context = SDGraphicsGetCurrentContext();
+    
+#if SD_UIKIT || SD_WATCH
+    // Core Graphics coordinate system use the bottom-left, UIKit use the flipped one
+    CGContextTranslateCTM(context, 0, targetRect.size.height);
+    CGContextScaleCTM(context, 1, -1);
+#endif
+    
+    CGContextConcatCTM(context, scaleTransform);
+    CGContextConcatCTM(context, transform);
+    
+    CGContextDrawPDFPage(context, page);
+    
+    image = SDGraphicsGetImageFromCurrentImageContext();
+    SDGraphicsEndImageContext();
+    
     CGPDFDocumentRelease(document);
     
-    return boxRect;
+    return image;
 }
 
 #pragma mark - Decode
@@ -113,6 +148,31 @@ static NSString * kSDCGImageDestinationRequestedFileSize = @"kCGImageDestination
         preserveAspectRatio = preserveAspectRatioValue.boolValue;
     }
     
+    // Check vector format
+    if ([NSData sd_imageFormatForImageData:data] == SDImageFormatPDF) {
+        // History before iOS 16, ImageIO can decode PDF with rasterization size, but can't ever :(
+        // So, use CoreGraphics to decode PDF (copy code from SDWebImagePDFCoder, may do refactor in the future)
+        UIImage *image;
+        NSUInteger pageNumber = 0; // Still use first page, may added options is user want
+#if SD_MAC
+        // If don't use thumbnail, prefers the built-in generation of vector image
+        // macOS's `NSImage` supports PDF built-in rendering
+        if (thumbnailSize.width == 0 || thumbnailSize.height == 0) {
+            NSPDFImageRep *imageRep = [[NSPDFImageRep alloc] initWithData:data];
+            if (imageRep) {
+                imageRep.currentPage = pageNumber;
+                image = [[NSImage alloc] initWithSize:imageRep.size];
+                [image addRepresentation:imageRep];
+                image.sd_imageFormat = SDImageFormatPDF;
+                return image;
+            }
+        }
+#endif
+        image = [self.class createBitmapPDFWithData:data pageNumber:pageNumber targetSize:thumbnailSize preserveAspectRatio:preserveAspectRatio];
+        image.sd_imageFormat = SDImageFormatPDF;
+        return image;
+    }
+    
     BOOL lazyDecode = YES; // Defaults YES for static image coder
     NSNumber *lazyDecodeValue = options[SDImageCoderDecodeUseLazyDecoding];
     if (lazyDecodeValue != nil) {
@@ -150,35 +210,9 @@ static NSString * kSDCGImageDestinationRequestedFileSize = @"kCGImageDestination
     
     CFStringRef uttype = CGImageSourceGetType(source);
     SDImageFormat imageFormat = [NSData sd_imageFormatFromUTType:uttype];
-    // Check vector format
-    NSDictionary *decodingOptions = nil;
-    if (imageFormat == SDImageFormatPDF) {
-        // Use 72 DPI (1:1 inch to pixel) by default, matching Apple's PDFKit behavior
-        NSUInteger rasterizationDPI = 72;
-        CGFloat maxPixelSize = MAX(thumbnailSize.width, thumbnailSize.height);
-        if (maxPixelSize > 0) {
-            // Calculate DPI based on PDF box and pixel size
-            CGRect boxRect = [self.class boxRectFromPDFFData:data];
-            CGFloat maxBoxSize = MAX(boxRect.size.width, boxRect.size.height);
-            if (maxBoxSize > 0) {
-                rasterizationDPI = rasterizationDPI * (maxPixelSize / maxBoxSize);
-            }
-        }
-        decodingOptions = @{
-            // This option will cause ImageIO return the pixel size from `CGImageSourceCopyProperties`
-            // If not provided, it always return 0 size
-            kSDCGImageSourceRasterizationDPI : @(rasterizationDPI),
-        };
-        // Already calculated DPI, avoid re-calculation based on thumbnail information
-        preserveAspectRatio = YES;
-        thumbnailSize = CGSizeZero;
-    }
     
-    UIImage *image = [SDImageIOAnimatedCoder createFrameAtIndex:0 source:source scale:scale preserveAspectRatio:preserveAspectRatio thumbnailSize:thumbnailSize lazyDecode:lazyDecode options:decodingOptions];
+    UIImage *image = [SDImageIOAnimatedCoder createFrameAtIndex:0 source:source scale:scale preserveAspectRatio:preserveAspectRatio thumbnailSize:thumbnailSize lazyDecode:lazyDecode options:nil];
     CFRelease(source);
-    if (!image) {
-        return nil;
-    }
     
     image.sd_imageFormat = imageFormat;
     return image;

Tests/Tests/SDImageCoderTests.m

@@ -11,12 +11,6 @@
 #import "UIColor+SDHexString.h"
 #import <SDWebImageWebPCoder/SDWebImageWebPCoder.h>
 
-@interface SDImageIOCoder ()
-
-+ (CGRect)boxRectFromPDFFData:(nonnull NSData *)data;
-
-@end
-
 @interface SDWebImageDecoderTests : SDTestCase
 
 @end
@@ -484,7 +478,7 @@ withLocalImageURL:(NSURL *)imageUrl
     expect(pixelHeight).beGreaterThan(0);
     // check vector format should use 72 DPI
     if (isVector) {
-        CGRect boxRect = [SDImageIOCoder boxRectFromPDFFData:inputImageData];
+        CGRect boxRect = [self boxRectFromPDFData:inputImageData];
         expect(boxRect.size.width).beGreaterThan(0);
         expect(boxRect.size.height).beGreaterThan(0);
         // Since 72 DPI is 1:1 from inch size to pixel size
@@ -564,4 +558,29 @@ withLocalImageURL:(NSURL *)imageUrl
     return thumbnailImages;
 }
 
+#pragma mark - Utils
+- (CGRect)boxRectFromPDFData:(nonnull NSData *)data {
+    CGDataProviderRef provider = CGDataProviderCreateWithCFData((__bridge CFDataRef)data);
+    if (!provider) {
+        return CGRectZero;
+    }
+    CGPDFDocumentRef document = CGPDFDocumentCreateWithProvider(provider);
+    CGDataProviderRelease(provider);
+    if (!document) {
+        return CGRectZero;
+    }
+    
+    // `CGPDFDocumentGetPage` page number is 1-indexed.
+    CGPDFPageRef page = CGPDFDocumentGetPage(document, 1);
+    if (!page) {
+        CGPDFDocumentRelease(document);
+        return CGRectZero;
+    }
+    
+    CGRect boxRect = CGPDFPageGetBoxRect(page, kCGPDFMediaBox);
+    CGPDFDocumentRelease(document);
+    
+    return boxRect;
+}
+
 @end