Is there documentation describing the semantics of a Metal CIKernel function?
I have image data where each pixel is a signed 16-bit integer. I need to convert that into any number of color values, starting with a simple shift from signed to unsigned (e.g. the data in one image ranges from about -8,000 to +20,000, and I want to simply add 8,000 to each pixel's value).
I've got a basic filter working, but it treats the pixel values as floating point, I think. I've tried using both sample_t and sample_h types in my kernel, and simple arithmetic:
extern "C"
coreimage::sample_h
heightShader(coreimage::sample_h inS, coreimage::destination inDest)
{
coreimage::sample_h r = inS + 0.1;
return r;
}
This has an effect, but I don't really know what's in inS. Is it a vector of four float16? What are the minimum and maximum values? They seem to be clamped to 1.0 (and perhaps -1.0). Well, I’ve told CI that my input image is CIFormat.L16, which is 16-bit luminance, so I imagine it's interpreting the bits as unsigned? Anyway, where is this documented, if anywhere (the correspondence between input image pixel format and the actual values that get passed to a filter kernel)?
Is there a type that lets me work on the integer values? This document - https://developer.apple.com/metal/MetalCIKLReference6.pdf implies that I can only work with floating-point values. But it doesn't tell me how they're mapped.
Any help would be appreciated. Thanks.
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I have some code calling this method:
mutating
func
readOffset() UInt64
{
let offset: UInt64
debugLog("readOffset")
switch (self.formatVersion)
{
case .v42:
let offset32: UInt32 = self.reader.get()
offset = UInt64(offset32)
case .v43:
offset = self.reader.get()
}
return offset
}
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If I put the breakpoint on debugLog(), it stops at the breakpoint.
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Xcode 12.4 (12D4e) on Catalina 10.15.7 (19H524).
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It zooms
Marquee-selection
Mouse down, drag, and up changes the model in significant and varied ways.
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I'm developing a little USB device for use with macOS, and the name includes the non-ASCII character ū:
LATIN SMALL LETTER U WITH MACRON
Unicode: U+016B, UTF-8: C5 AB
My source file is UTF-8 encoded, but as I understand it, USB uses UTF-16LE encoding for all its strings.
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If I put the main SQLite file to open inside the app's container, then SQLite can open the associated files just fine.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>CFBundleDevelopmentRegion</key>
<string>$(DEVELOPMENT_LANGUAGE)</string>
<key>CFBundleDocumentTypes</key>
<array>
<dict>
<key>CFBundleTypeName</key>
<string>SQLiteDocument</string>
<key>CFBundleTypeRole</key>
<string>Editor</string>
<key>LSHandlerRank</key>
<string>Default</string>
<key>LSItemContentTypes</key>
<array>
<string>org.sqlite.sqlite3</string>
</array>
<key>NSDocumentClass</key>
<string>$(PRODUCT_MODULE_NAME).Document</string>
</dict>
		<dict>
				<key>CFBundleTypeExtensions</key>
				<array>
						<string>sqlite-shm</string>
						<string>sqlite-wal</string>
						<string>sqlite-journal</string>
				</array>
				<key>CFBundleTypeName</key>
				<string>Support Type</string>
				<key>CFBundleTypeRole</key>
				<string>Editor</string>
				<key>NSIsRelatedItemType</key>
				<true/>
		</dict>
</array>
<key>CFBundleExecutable</key>
<string>$(EXECUTABLE_NAME)</string>
<key>CFBundleIconFile</key>
<string></string>
<key>CFBundleIdentifier</key>
<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
<key>CFBundleInfoDictionaryVersion</key>
<string>6.0</string>
<key>CFBundleName</key>
<string>$(PRODUCT_NAME)</string>
<key>CFBundlePackageType</key>
<string>$(PRODUCT_BUNDLE_PACKAGE_TYPE)</string>
<key>CFBundleShortVersionString</key>
<string>1.0</string>
<key>CFBundleVersion</key>
<string>1</string>
<key>LSMinimumSystemVersion</key>
<string>$(MACOSX_DEPLOYMENT_TARGET)</string>
<key>NSMainStoryboardFile</key>
<string>Main</string>
<key>NSPrincipalClass</key>
<string>NSApplication</string>
<key>UTExportedTypeDeclarations</key>
<array>
<dict>
<key>UTTypeConformsTo</key>
<array>
<string>public.database</string>
<string>public.data</string>
</array>
<key>UTTypeDescription</key>
<string>SQLite3</string>
<key>UTTypeIcons</key>
<dict/>
<key>UTTypeIdentifier</key>
<string>org.sqlite.sqlite3</string>
<key>UTTypeTagSpecification</key>
<dict>
<key>public.filename-extension</key>
<array>
<string>sqlite</string>
</array>
</dict>
</dict>
</array>
<key>UTImportedTypeDeclarations</key>
<array>
<dict>
<key>UTTypeConformsTo</key>
<array>
<string>public.database</string>
<string>public.data</string>
</array>
<key>UTTypeDescription</key>
<string>SQLite3</string>
<key>UTTypeIcons</key>
<dict/>
<key>UTTypeIdentifier</key>
<string>org.sqlite.sqlite3</string>
<key>UTTypeTagSpecification</key>
<dict>
<key>public.filename-extension</key>
<array>
<string>sqlite</string>
</array>
</dict>
</dict>
</array>
</dict>
</plist>