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February 13, 2022 20:35
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Creates a deep copy of a CVPixelBuffer. Compatible with Swift 2.3.
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extension CVPixelBuffer | |
{ | |
/// Deep copy a CVPixelBuffer: | |
/// http://stackoverflow.com/questions/38335365/pulling-data-from-a-cmsamplebuffer-in-order-to-create-a-deep-copy | |
func copy() -> CVPixelBuffer | |
{ | |
precondition(CFGetTypeID(self) == CVPixelBufferGetTypeID(), "copy() cannot be called on a non-CVPixelBuffer") | |
var _copy: CVPixelBuffer? | |
CVPixelBufferCreate( | |
nil, | |
CVPixelBufferGetWidth(self), | |
CVPixelBufferGetHeight(self), | |
CVPixelBufferGetPixelFormatType(self), | |
CVBufferGetAttachments(self, .ShouldPropagate), | |
&_copy) | |
guard let copy = _copy else { fatalError() } | |
CVPixelBufferLockBaseAddress(self, .ReadOnly) | |
CVPixelBufferLockBaseAddress(copy, []) | |
defer | |
{ | |
CVPixelBufferUnlockBaseAddress(copy, []) | |
CVPixelBufferUnlockBaseAddress(self, .ReadOnly) | |
} | |
for plane in 0 ..< CVPixelBufferGetPlaneCount(self) | |
{ | |
let dest = CVPixelBufferGetBaseAddressOfPlane(copy, plane) | |
let source = CVPixelBufferGetBaseAddressOfPlane(self, plane) | |
let height = CVPixelBufferGetHeightOfPlane(self, plane) | |
let bytesPerRow = CVPixelBufferGetBytesPerRowOfPlane(self, plane) | |
memcpy(dest, source, height * bytesPerRow) | |
} | |
return copy | |
} | |
} |
This assumes the buffer is planar. Can you update the code to support non-planar buffer? Thx
Seems this is that you want
https://stackoverflow.com/a/58647596/752651
public extension CVPixelBuffer {
func copy() throws -> CVPixelBuffer {
precondition(CFGetTypeID(self) == CVPixelBufferGetTypeID(), "copy() cannot be called on a non-CVPixelBuffer")
var _copy: CVPixelBuffer?
let width = CVPixelBufferGetWidth(self)
let height = CVPixelBufferGetHeight(self)
let formatType = CVPixelBufferGetPixelFormatType(self)
let attachments = CVBufferGetAttachments(self, .shouldPropagate)
CVPixelBufferCreate(nil, width, height, formatType, attachments, &_copy)
guard let copy = _copy else {
throw PixelBufferCopyError.allocationFailed
}
CVPixelBufferLockBaseAddress(self, .readOnly)
CVPixelBufferLockBaseAddress(copy, [])
defer {
CVPixelBufferUnlockBaseAddress(copy, [])
CVPixelBufferUnlockBaseAddress(self, .readOnly)
}
let pixelBufferPlaneCount: Int = CVPixelBufferGetPlaneCount(self)
if pixelBufferPlaneCount == 0 {
let dest = CVPixelBufferGetBaseAddress(copy)
let source = CVPixelBufferGetBaseAddress(self)
let height = CVPixelBufferGetHeight(self)
let bytesPerRowSrc = CVPixelBufferGetBytesPerRow(self)
let bytesPerRowDest = CVPixelBufferGetBytesPerRow(copy)
if bytesPerRowSrc == bytesPerRowDest {
memcpy(dest, source, height * bytesPerRowSrc)
}else {
var startOfRowSrc = source
var startOfRowDest = dest
for _ in 0..<height {
memcpy(startOfRowDest, startOfRowSrc, min(bytesPerRowSrc, bytesPerRowDest))
startOfRowSrc = startOfRowSrc?.advanced(by: bytesPerRowSrc)
startOfRowDest = startOfRowDest?.advanced(by: bytesPerRowDest)
}
}
}else {
for plane in 0 ..< pixelBufferPlaneCount {
let dest = CVPixelBufferGetBaseAddressOfPlane(copy, plane)
let source = CVPixelBufferGetBaseAddressOfPlane(self, plane)
let height = CVPixelBufferGetHeightOfPlane(self, plane)
let bytesPerRowSrc = CVPixelBufferGetBytesPerRowOfPlane(self, plane)
let bytesPerRowDest = CVPixelBufferGetBytesPerRowOfPlane(copy, plane)
if bytesPerRowSrc == bytesPerRowDest {
memcpy(dest, source, height * bytesPerRowSrc)
}else {
var startOfRowSrc = source
var startOfRowDest = dest
for _ in 0..<height {
memcpy(startOfRowDest, startOfRowSrc, min(bytesPerRowSrc, bytesPerRowDest))
startOfRowSrc = startOfRowSrc?.advanced(by: bytesPerRowSrc)
startOfRowDest = startOfRowDest?.advanced(by: bytesPerRowDest)
}
}
}
}
return copy
}
}
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This assumes the buffer is planar. Can you update the code to support non-planar buffer? Thx