diff --git a/modules/juce_audio_plugin_client/Unity/juce_Unity_Wrapper.cpp b/modules/juce_audio_plugin_client/Unity/juce_Unity_Wrapper.cpp
index 753af3127f..7aae5b91e9 100644
--- a/modules/juce_audio_plugin_client/Unity/juce_Unity_Wrapper.cpp
+++ b/modules/juce_audio_plugin_client/Unity/juce_Unity_Wrapper.cpp
@@ -162,7 +162,9 @@ private:
         {
             ignoreUnused (mode);
 
-            bitmap.data = imageData + x * pixelStride + y * lineStride;
+            const auto offset = (size_t) x * (size_t) pixelStride + (size_t) y * (size_t) lineStride;
+            bitmap.data = imageData + offset;
+            bitmap.size = (size_t) (lineStride * height) - offset;
             bitmap.pixelFormat = pixelFormat;
             bitmap.lineStride = lineStride;
             bitmap.pixelStride = pixelStride;
diff --git a/modules/juce_graphics/images/juce_Image.cpp b/modules/juce_graphics/images/juce_Image.cpp
index 10213980ed..c4355fe78b 100644
--- a/modules/juce_graphics/images/juce_Image.cpp
+++ b/modules/juce_graphics/images/juce_Image.cpp
@@ -97,7 +97,9 @@ public:
 
     void initialiseBitmapData (Image::BitmapData& bitmap, int x, int y, Image::BitmapData::ReadWriteMode mode) override
     {
-        bitmap.data = imageData + (size_t) x * (size_t) pixelStride + (size_t) y * (size_t) lineStride;
+        const auto offset = (size_t) x * (size_t) pixelStride + (size_t) y * (size_t) lineStride;
+        bitmap.data = imageData + offset;
+        bitmap.size = (size_t) (height * lineStride) - offset;
         bitmap.pixelFormat = pixelFormat;
         bitmap.lineStride = lineStride;
         bitmap.pixelStride = pixelStride;
diff --git a/modules/juce_graphics/images/juce_Image.h b/modules/juce_graphics/images/juce_Image.h
index 714472304f..62bb19fd27 100644
--- a/modules/juce_graphics/images/juce_Image.h
+++ b/modules/juce_graphics/images/juce_Image.h
@@ -349,6 +349,7 @@ public:
         Rectangle<int> getBounds() const noexcept                           { return Rectangle<int> (width, height); }
 
         uint8* data;             /**< The raw pixel data, packed according to the image's pixel format. */
+        size_t size;             /**< The number of valid/allocated bytes after data. May be smaller than "lineStride * height" if this is a section of a larger image. */
         PixelFormat pixelFormat; /**< The format of the data. */
         int lineStride;          /**< The number of bytes between each line. */
         int pixelStride;         /**< The number of bytes between each pixel. */
diff --git a/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm b/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm
index 941862203b..df5f9f9487 100644
--- a/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm
+++ b/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm
@@ -71,7 +71,9 @@ public:
 
     void initialiseBitmapData (Image::BitmapData& bitmap, int x, int y, Image::BitmapData::ReadWriteMode mode) override
     {
-        bitmap.data = imageData->data + x * pixelStride + y * lineStride;
+        const auto offset = (size_t) (x * pixelStride + y * lineStride);
+        bitmap.data = imageData->data + offset;
+        bitmap.size = (size_t) (lineStride * height) - offset;
         bitmap.pixelFormat = pixelFormat;
         bitmap.lineStride = lineStride;
         bitmap.pixelStride = pixelStride;
@@ -111,22 +113,20 @@ public:
     static CGImageRef createImage (const Image& juceImage, CGColorSpaceRef colourSpace)
     {
         const Image::BitmapData srcData (juceImage, Image::BitmapData::readOnly);
-        detail::DataProviderPtr provider;
 
-        if (auto* cgim = dynamic_cast<CoreGraphicsPixelData*> (juceImage.getPixelData()))
+        const auto provider = [&]
         {
-            provider = detail::DataProviderPtr { CGDataProviderCreateWithData (new ImageDataContainer::Ptr (cgim->imageData),
+            if (auto* cgim = dynamic_cast<CoreGraphicsPixelData*> (juceImage.getPixelData()))
+            {
+                return detail::DataProviderPtr { CGDataProviderCreateWithData (new ImageDataContainer::Ptr (cgim->imageData),
                                                                                srcData.data,
-                                                                               (size_t) srcData.lineStride * (size_t) srcData.height,
+                                                                               srcData.size,
                                                                                [] (void * __nullable info, const void*, size_t) { delete (ImageDataContainer::Ptr*) info; }) };
-        }
-        else
-        {
-            CFUniquePtr<CFDataRef> data (CFDataCreate (nullptr,
-                                                       (const UInt8*) srcData.data,
-                                                       (CFIndex) ((size_t) srcData.lineStride * (size_t) srcData.height)));
-            provider = detail::DataProviderPtr { CGDataProviderCreateWithCFData (data.get()) };
-        }
+            }
+
+            CFUniquePtr<CFDataRef> data (CFDataCreate (nullptr, (const UInt8*) srcData.data, (CFIndex) srcData.size));
+            return detail::DataProviderPtr { CGDataProviderCreateWithCFData (data.get()) };
+        }();
 
         CGImageRef imageRef = CGImageCreate ((size_t) srcData.width,
                                              (size_t) srcData.height,
@@ -512,7 +512,7 @@ void CoreGraphicsContext::drawImage (const Image& sourceImage, const AffineTrans
 
     auto colourSpace = sourceImage.getFormat() == Image::PixelFormat::SingleChannel ? greyColourSpace.get()
                                                                                     : rgbColourSpace.get();
-    auto image = detail::ImagePtr { CoreGraphicsPixelData::getCachedImageRef (sourceImage, colourSpace) };
+    detail::ImagePtr image { CoreGraphicsPixelData::getCachedImageRef (sourceImage, colourSpace) };
 
     ScopedCGContextState scopedState (context.get());
     CGContextSetAlpha (context.get(), state->fillType.getOpacity());
diff --git a/modules/juce_gui_basics/native/juce_android_Windowing.cpp b/modules/juce_gui_basics/native/juce_android_Windowing.cpp
index 3c4074b0df..7609d0181f 100644
--- a/modules/juce_gui_basics/native/juce_android_Windowing.cpp
+++ b/modules/juce_gui_basics/native/juce_android_Windowing.cpp
@@ -1213,7 +1213,9 @@ private:
             bm.lineStride = width * static_cast<int> (sizeof (jint));
             bm.pixelStride = static_cast<int> (sizeof (jint));
             bm.pixelFormat = Image::ARGB;
-            bm.data = (uint8*) (data + x + y * width);
+            const auto offset = (size_t) x + (size_t) y * (size_t) width;
+            bm.data = (uint8*) (data + offset);
+            bm.size = sizeof (jint) * (((size_t) height * (size_t) width) - offset);
         }
 
         ImagePixelData::Ptr clone() override
diff --git a/modules/juce_gui_basics/native/juce_win32_Windowing.cpp b/modules/juce_gui_basics/native/juce_win32_Windowing.cpp
index 5066806812..b2520020b3 100644
--- a/modules/juce_gui_basics/native/juce_win32_Windowing.cpp
+++ b/modules/juce_gui_basics/native/juce_win32_Windowing.cpp
@@ -990,7 +990,9 @@ public:
 
     void initialiseBitmapData (Image::BitmapData& bitmap, int x, int y, Image::BitmapData::ReadWriteMode mode) override
     {
-        bitmap.data = imageData + x * pixelStride + y * lineStride;
+        const auto offset = (size_t) (x * pixelStride + y * lineStride);
+        bitmap.data = imageData + offset;
+        bitmap.size = (size_t) (lineStride * height) - offset;
         bitmap.pixelFormat = pixelFormat;
         bitmap.lineStride = lineStride;
         bitmap.pixelStride = pixelStride;
diff --git a/modules/juce_gui_basics/native/x11/juce_linux_XWindowSystem.cpp b/modules/juce_gui_basics/native/x11/juce_linux_XWindowSystem.cpp
index d1d7674170..059e98e25d 100644
--- a/modules/juce_gui_basics/native/x11/juce_linux_XWindowSystem.cpp
+++ b/modules/juce_gui_basics/native/x11/juce_linux_XWindowSystem.cpp
@@ -968,7 +968,9 @@ public:
     void initialiseBitmapData (Image::BitmapData& bitmap, int x, int y,
                                Image::BitmapData::ReadWriteMode mode) override
     {
-        bitmap.data = imageData + x * pixelStride + y * lineStride;
+        const auto offset = (size_t) (x * pixelStride + y * lineStride);
+        bitmap.data = imageData + offset;
+        bitmap.size = (size_t) (lineStride * height) - offset;
         bitmap.pixelFormat = pixelFormat;
         bitmap.lineStride = lineStride;
         bitmap.pixelStride = pixelStride;
diff --git a/modules/juce_opengl/opengl/juce_OpenGLImage.cpp b/modules/juce_opengl/opengl/juce_OpenGLImage.cpp
index 716cec6473..709b6778da 100644
--- a/modules/juce_opengl/opengl/juce_OpenGLImage.cpp
+++ b/modules/juce_opengl/opengl/juce_OpenGLImage.cpp
@@ -168,6 +168,9 @@ private:
             bitmapData.dataReleaser.reset (r);
 
             bitmapData.data = (uint8*) r->data.get();
+            bitmapData.size = (size_t) bitmapData.width
+                              * (size_t) bitmapData.height
+                              * sizeof (PixelARGB);
             bitmapData.lineStride = (bitmapData.width * bitmapData.pixelStride + 3) & ~3;
 
             ReaderType::read (frameBuffer, bitmapData, x, y);