2014/10/15 下午 10:12:37

iphone Programming Glossary: pixels

UIImagePickerController and extracting EXIF data from existing photos

http://stackoverflow.com/questions/1238838/uiimagepickercontroller-and-extracting-exif-data-from-existing-photos

image that was selected. I'm considering making a table of hashes and matching against the first x pixels of each image. This seems a bit over the top though and probably quite slow. Any suggestions iphone..

How to develop or migrate apps for iPhone 5 screen resolution?

http://stackoverflow.com/questions/12395200/how-to-develop-or-migrate-apps-for-iphone-5-screen-resolution

screen resolution The new iPhone 5 display has a new aspect ratio and a new resolution 640 x 1136 pixels . What is required to develop new or transition already existing applications to the new screen size..

iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]

http://stackoverflow.com/questions/12396545/ios-6-apps-how-to-deal-with-iphone-5-screen-size

I was just wondering with how should we deal with the iPhone 5 bigger screen size. As it has more pixels in height things like GCRectMake that use coordinates and just doubled the pixels with the retina non.. As it has more pixels in height things like GCRectMake that use coordinates and just doubled the pixels with the retina non retina problem won't work seamlessly between versions as it happened when we got.. . If that sounds ugly then you could go with the default letterboxed model where the extra points pixels just show up black. Edit To enable your apps to work with iPhone 5 you need to add a retina version..

Resizing UIimages pulled from the Camera also ROTATES the UIimage?

http://stackoverflow.com/questions/1260249/resizing-uiimages-pulled-from-the-camera-also-rotates-the-uiimage

UIImageView the image is rotated 90 degrees and appears stretched as the aspect ratio 1200 x 1600 pixels was unchanged... I am using this to get a UIImage from the Camera void imagePickerController UIImagePickerController.. ref return result QUESTION How do I RESIZE a UIImage pulled from the Camera WITHOUT rotating the pixels iphone uiimageview uiimage uiimagepickercontroller share improve this question The reason your..

How to Rotate a UIImage 90 degrees?

http://stackoverflow.com/questions/1315251/how-to-rotate-a-uiimage-90-degrees

counter clockwise by 90 degrees to landscape . I don't want to use a CGAffineTransform. I want the pixels of the UIImage to actually shift position. I am using a block of code shown below originally intended..

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

we will divide each unit as 3 bytes 1 pixel . pixelData RGBPixel pixelByteData Now you can access pixels by index pixelData index NSLog @ Pixel data one red i green i blue i . pixelData 0 .red pixelData 0..

The simplest way to resize an UIImage?

http://stackoverflow.com/questions/2658738/the-simplest-way-to-resize-an-uiimage

an UIImage In my iPhone app I take a picture with the camera then I want to resize it to 290 390 pixels. I was using this method to resize the image UIImage newImage image _imageScaledToSize CGSizeMake 290..

OpenGL Texture Coordinates in Pixel Space

http://stackoverflow.com/questions/5879403/opengl-texture-coordinates-in-pixel-space

but I don't have the links at hand so a quick and rough explanation. Let's say the texture is 8 pixels wide 0 1 2 3 4 5 6 7 ^ ^ ^ ^ ^ ^ ^ ^ ^ 0.0 1.0 0 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote.. 7 ^ ^ ^ ^ ^ ^ ^ ^ ^ 0.0 1.0 0 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote the texture's pixels the bars the edges of the texture and in case of nearest filtering the border between pixels. You however.. pixels the bars the edges of the texture and in case of nearest filtering the border between pixels. You however want to hit the pixels' centers. So you're interested in the texture coordinates 0 8 1..

What's the easiest way to resize/optimize an image size with the iPhone SDK?

http://stackoverflow.com/questions/612131/whats-the-easiest-way-to-resize-optimize-an-image-size-with-the-iphone-sdk

them to the local iPhone disk. Some of those images are pretty big in size widths larger than 500 pixels for instance . Since the iPhone doesn't even have a big enough display to show the image in its original..

Faster alternative to glReadPixels in iPhone OpenGL ES 2.0

http://stackoverflow.com/questions/9550297/faster-alternative-to-glreadpixels-in-iphone-opengl-es-2-0

upload of camera frames to OpenGL ES but it can be used in reverse to get quick access to the raw pixels within an OpenGL ES texture. You can take advantage of this to grab the pixels for an OpenGL ES rendering.. access to the raw pixels within an OpenGL ES texture. You can take advantage of this to grab the pixels for an OpenGL ES rendering by using a framebuffer object FBO with an attached texture with that texture.. having been supplied from the texture cache. Once you render your scene into that FBO the BGRA pixels for that scene will be contained within your CVPixelBufferRef so there will be no need to pull them..

UIImagePickerController and extracting EXIF data from existing photos

http://stackoverflow.com/questions/1238838/uiimagepickercontroller-and-extracting-exif-data-from-existing-photos

UIImage making it impossible to know the file size of the image that was selected. I'm considering making a table of hashes and matching against the first x pixels of each image. This seems a bit over the top though and probably quite slow. Any suggestions iphone cocoa touch gps uiimagepickercontroller exif share improve..

How to develop or migrate apps for iPhone 5 screen resolution?

http://stackoverflow.com/questions/12395200/how-to-develop-or-migrate-apps-for-iphone-5-screen-resolution

to develop or migrate apps for iPhone 5 screen resolution The new iPhone 5 display has a new aspect ratio and a new resolution 640 x 1136 pixels . What is required to develop new or transition already existing applications to the new screen size What should we keep in mind to make applications universal..

iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]

http://stackoverflow.com/questions/12396545/ios-6-apps-how-to-deal-with-iphone-5-screen-size

to develop or migrate apps for iPhone 5 screen resolution I was just wondering with how should we deal with the iPhone 5 bigger screen size. As it has more pixels in height things like GCRectMake that use coordinates and just doubled the pixels with the retina non retina problem won't work seamlessly between versions as it.. with how should we deal with the iPhone 5 bigger screen size. As it has more pixels in height things like GCRectMake that use coordinates and just doubled the pixels with the retina non retina problem won't work seamlessly between versions as it happened when we got the Retina . And will we have to design two storyboards just.. option is to have two UIs pre iPhone 5 and iPhone 5 . If that sounds ugly then you could go with the default letterboxed model where the extra points pixels just show up black. Edit To enable your apps to work with iPhone 5 you need to add a retina version of the launcher image. It should be named Default 568h@2x.png..

Resizing UIimages pulled from the Camera also ROTATES the UIimage?

http://stackoverflow.com/questions/1260249/resizing-uiimages-pulled-from-the-camera-also-rotates-the-uiimage

As a result when I assign the resized UIImage to a UIImageView the image is rotated 90 degrees and appears stretched as the aspect ratio 1200 x 1600 pixels was unchanged... I am using this to get a UIImage from the Camera void imagePickerController UIImagePickerController picker didFinishPickingMediaWithInfo NSDictionary.. imageWithCGImage ref CGContextRelease bitmap CGImageRelease ref return result QUESTION How do I RESIZE a UIImage pulled from the Camera WITHOUT rotating the pixels iphone uiimageview uiimage uiimagepickercontroller share improve this question The reason your code doesn't work is because the imageOrientation on the code..

How to Rotate a UIImage 90 degrees?

http://stackoverflow.com/questions/1315251/how-to-rotate-a-uiimage-90-degrees

UIImageOrientationUp portrait that I would like to rotate counter clockwise by 90 degrees to landscape . I don't want to use a CGAffineTransform. I want the pixels of the UIImage to actually shift position. I am using a block of code shown below originally intended to resize a UIImage to do this. I set a target size as the..

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

units differently instead of dividing each unit as 1 byte we will divide each unit as 3 bytes 1 pixel . pixelData RGBPixel pixelByteData Now you can access pixels by index pixelData index NSLog @ Pixel data one red i green i blue i . pixelData 0 .red pixelData 0 .green pixelData 0 .blue You can determine the desired index..

The simplest way to resize an UIImage?

http://stackoverflow.com/questions/2658738/the-simplest-way-to-resize-an-uiimage

simplest way to resize an UIImage In my iPhone app I take a picture with the camera then I want to resize it to 290 390 pixels. I was using this method to resize the image UIImage newImage image _imageScaledToSize CGSizeMake 290 390 interpolationQuality 1 It works perfectly but it's an..

OpenGL Texture Coordinates in Pixel Space

http://stackoverflow.com/questions/5879403/opengl-texture-coordinates-in-pixel-space

share improve this question This has been asked a few times but I don't have the links at hand so a quick and rough explanation. Let's say the texture is 8 pixels wide 0 1 2 3 4 5 6 7 ^ ^ ^ ^ ^ ^ ^ ^ ^ 0.0 1.0 0 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote the texture's pixels the bars the edges of the texture and.. Let's say the texture is 8 pixels wide 0 1 2 3 4 5 6 7 ^ ^ ^ ^ ^ ^ ^ ^ ^ 0.0 1.0 0 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote the texture's pixels the bars the edges of the texture and in case of nearest filtering the border between pixels. You however want to hit the pixels' centers. So you're interested.. 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote the texture's pixels the bars the edges of the texture and in case of nearest filtering the border between pixels. You however want to hit the pixels' centers. So you're interested in the texture coordinates 0 8 1 8 2 1 2 8 1 8 2 8 2 3 2 8 ... 7 8 8 8 2 15 2 8 Or more generally..

What's the easiest way to resize/optimize an image size with the iPhone SDK?

http://stackoverflow.com/questions/612131/whats-the-easiest-way-to-resize-optimize-an-image-size-with-the-iphone-sdk

downloading a set of image files from the network and saving them to the local iPhone disk. Some of those images are pretty big in size widths larger than 500 pixels for instance . Since the iPhone doesn't even have a big enough display to show the image in its original size I'm planning on resizing the image to something a..

Faster alternative to glReadPixels in iPhone OpenGL ES 2.0

http://stackoverflow.com/questions/9550297/faster-alternative-to-glreadpixels-in-iphone-opengl-es-2-0

cache support added in iOS 5.0 doesn't just work for fast upload of camera frames to OpenGL ES but it can be used in reverse to get quick access to the raw pixels within an OpenGL ES texture. You can take advantage of this to grab the pixels for an OpenGL ES rendering by using a framebuffer object FBO with an attached texture.. to OpenGL ES but it can be used in reverse to get quick access to the raw pixels within an OpenGL ES texture. You can take advantage of this to grab the pixels for an OpenGL ES rendering by using a framebuffer object FBO with an attached texture with that texture having been supplied from the texture cache. Once you render.. object FBO with an attached texture with that texture having been supplied from the texture cache. Once you render your scene into that FBO the BGRA pixels for that scene will be contained within your CVPixelBufferRef so there will be no need to pull them down using glReadPixels . This is much much faster than using..

UIImagePickerController and extracting EXIF data from existing photos

http://stackoverflow.com/questions/1238838/uiimagepickercontroller-and-extracting-exif-data-from-existing-photos

file size of the image that was selected. I'm considering making a table of hashes and matching against the first x pixels of each image. This seems a bit over the top though and probably quite slow. Any suggestions iphone cocoa touch gps uiimagepickercontroller..

How to develop or migrate apps for iPhone 5 screen resolution?

http://stackoverflow.com/questions/12395200/how-to-develop-or-migrate-apps-for-iphone-5-screen-resolution

apps for iPhone 5 screen resolution The new iPhone 5 display has a new aspect ratio and a new resolution 640 x 1136 pixels . What is required to develop new or transition already existing applications to the new screen size What should we keep..

iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]

http://stackoverflow.com/questions/12396545/ios-6-apps-how-to-deal-with-iphone-5-screen-size

5 screen resolution I was just wondering with how should we deal with the iPhone 5 bigger screen size. As it has more pixels in height things like GCRectMake that use coordinates and just doubled the pixels with the retina non retina problem won't.. 5 bigger screen size. As it has more pixels in height things like GCRectMake that use coordinates and just doubled the pixels with the retina non retina problem won't work seamlessly between versions as it happened when we got the Retina . And will.. 5 and iPhone 5 . If that sounds ugly then you could go with the default letterboxed model where the extra points pixels just show up black. Edit To enable your apps to work with iPhone 5 you need to add a retina version of the launcher image...

How to Rotate a UIImage 90 degrees?

http://stackoverflow.com/questions/1315251/how-to-rotate-a-uiimage-90-degrees

like to rotate counter clockwise by 90 degrees to landscape . I don't want to use a CGAffineTransform. I want the pixels of the UIImage to actually shift position. I am using a block of code shown below originally intended to resize a UIImage..

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

each unit as 1 byte we will divide each unit as 3 bytes 1 pixel . pixelData RGBPixel pixelByteData Now you can access pixels by index pixelData index NSLog @ Pixel data one red i green i blue i . pixelData 0 .red pixelData 0 .green pixelData 0 .blue..

The simplest way to resize an UIImage?

http://stackoverflow.com/questions/2658738/the-simplest-way-to-resize-an-uiimage

way to resize an UIImage In my iPhone app I take a picture with the camera then I want to resize it to 290 390 pixels. I was using this method to resize the image UIImage newImage image _imageScaledToSize CGSizeMake 290 390 interpolationQuality..

OpenGL Texture Coordinates in Pixel Space

http://stackoverflow.com/questions/5879403/opengl-texture-coordinates-in-pixel-space

been asked a few times but I don't have the links at hand so a quick and rough explanation. Let's say the texture is 8 pixels wide 0 1 2 3 4 5 6 7 ^ ^ ^ ^ ^ ^ ^ ^ ^ 0.0 1.0 0 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote the texture's pixels.. wide 0 1 2 3 4 5 6 7 ^ ^ ^ ^ ^ ^ ^ ^ ^ 0.0 1.0 0 8 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 The digits denote the texture's pixels the bars the edges of the texture and in case of nearest filtering the border between pixels. You however want to hit the.. denote the texture's pixels the bars the edges of the texture and in case of nearest filtering the border between pixels. You however want to hit the pixels' centers. So you're interested in the texture coordinates 0 8 1 8 2 1 2 8 1 8 2 8 2..

What's the easiest way to resize/optimize an image size with the iPhone SDK?

http://stackoverflow.com/questions/612131/whats-the-easiest-way-to-resize-optimize-an-image-size-with-the-iphone-sdk

network and saving them to the local iPhone disk. Some of those images are pretty big in size widths larger than 500 pixels for instance . Since the iPhone doesn't even have a big enough display to show the image in its original size I'm planning..

Changing pen width according writing speed

http://stackoverflow.com/questions/6490057/changing-pen-width-according-writing-speed

Undo drawing in Paint Application

http://stackoverflow.com/questions/6689600/undo-drawing-in-paint-application

setCurrentContext context glBindFramebufferOES GL_FRAMEBUFFER_OES viewFramebuffer Convert locations from Points to Pixels CGFloat scale 1.0 self.contentScaleFactor start.x scale start.y scale end.x scale end.y scale Allocate vertex array buffer..

Save OpenGL Drawn item as a Image

http://stackoverflow.com/questions/9660723/save-opengl-drawn-item-as-a-image

setCurrentContext context glBindFramebufferOES GL_FRAMEBUFFER_OES viewFramebuffer Convert locations from Points to Pixels CGFloat scale self.contentScaleFactor start.x scale start.y scale end.x scale end.y scale Allocate vertex array buffer if.. glMatrixMode GL_PROJECTION CGRect frame self.bounds CGFloat scale self.contentScaleFactor Setup the view port in Pixels glOrthof 0 frame.size.width scale 0 frame.size.height scale 1 1 glViewport 0 0 frame.size.width scale frame.size.height.. myDataLength 320 480 4 allocate array and read pixels into it. GLubyte buffer GLubyte malloc myDataLength glReadPixels 0 0 320 480 GL_RGBA GL_UNSIGNED_BYTE buffer gl renders upside down so swap top to bottom into new array. there's gotta be..

Record the drawing as a m4v video file - OpenGL

http://stackoverflow.com/questions/9661259/record-the-drawing-as-a-m4v-video-file-opengl

setCurrentContext context glBindFramebufferOES GL_FRAMEBUFFER_OES viewFramebuffer Convert locations from Points to Pixels CGFloat scale self.contentScaleFactor start.x scale start.y scale end.x scale end.y scale Allocate vertex array buffer if.. glMatrixMode GL_PROJECTION CGRect frame self.bounds CGFloat scale self.contentScaleFactor Setup the view port in Pixels glOrthof 0 frame.size.width scale 0 frame.size.height scale 1 1 glViewport 0 0 frame.size.width scale frame.size.height.. you'll need to provide frames to the writer in BGRA format not the RGBA you get from reading the screen using glReadPixels . In my case I used a color swizzling shader to convert from RGBA to BGRA before reading but you don't have that option..