2014/10/15 下午 10:04:27

iphone Programming Glossary: average

How to implement a box or gaussian blur on iPhone

http://stackoverflow.com/questions/1140117/how-to-implement-a-box-or-gaussian-blur-on-iphone

say in 0.1 sec . Image size would almost never be larger than 256 x 256 px. Do I have to loop thru every pixel and average them with neighbors or is there a higher level way that I could do this PS I am aware that multiple box blurs can approximate..

Is MonoTouch a viable platform for iPhone development?

http://stackoverflow.com/questions/1847274/is-monotouch-a-viable-platform-for-iphone-development

good iPhone apps and shouldn't be among the examples of attempts to write desktop apps for a phone which is where your average dev makes his first mistake when transitioning to mobile development . Ultimately your tool of choice isn't going to matter..

How do you use a moving average to filter out accelerometer values in iPhone OS

http://stackoverflow.com/questions/2272527/how-do-you-use-a-moving-average-to-filter-out-accelerometer-values-in-iphone-os

do you use a moving average to filter out accelerometer values in iPhone OS I want to filter the accelerometer values using a moving average how is.. average to filter out accelerometer values in iPhone OS I want to filter the accelerometer values using a moving average how is this done Thanks objective c iphone filter accelerometer moving average share improve this question A simple.. accelerometer values using a moving average how is this done Thanks objective c iphone filter accelerometer moving average share improve this question A simple single pole low pass recursive IIR filter is quick and easy to implement e.g. xf..

Detecting Acceleration in a car (iPhone Accelerometer)

http://stackoverflow.com/questions/2733249/detecting-acceleration-in-a-car-iphone-accelerometer

and actual driving. Our initial run was simple and suffered the consequences. During the calibration stage I took the average force on the phone and during running I just subtracted the average force from the current force to get the current acceleration.. During the calibration stage I took the average force on the phone and during running I just subtracted the average force from the current force to get the current acceleration this frame. The problem with this is that the typical car receives..

Levenshtein Distance Algorithm better than O(n*m)?

http://stackoverflow.com/questions/4057513/levenshtein-distance-algorithm-better-than-onm

share improve this question Are you interested in reducing the time complexity or the space complexity The average time complexity can be reduced O n d^2 where n is the length of the longer string and d is the edit distance. If you are..

Drawing waveform with AVAssetReader

http://stackoverflow.com/questions/5032775/drawing-waveform-with-avassetreader

MediaPlayer MediaPlayer.h #import AVFoundation AVFoundation.h First a generic rendering method that takes a pointer to averaged sample data and returns a UIImage. Note these samples are not playable audio samples. UIImage audioImageGraph SInt16 samples.. if sampleTally samplesPerPixel left totalLeft sampleTally if left normalizeMax normalizeMax left NSLog @ left average f normalizeMax f left normalizeMax fullSongData appendBytes left length sizeof left if channelCount 2 right totalRight..

Tap pressure strength detection using accelerometer

http://stackoverflow.com/questions/5179426/tap-pressure-strength-detection-using-accelerometer

current pressure value pressureValues currentPressureValueIndex sz acceleration.z if setNextPressureValue 0 calculate average pressure float total 0.0f for int loop 0 loop sz loop total pressureValues loop float average total sz start with most recent.. 0 calculate average pressure float total 0.0f for int loop 0 loop sz loop total pressureValues loop float average total sz start with most recent past pressure sample if setNextPressureValue KNumberOfPressureSamples float mostRecent.. KNumberOfPressureSamples float mostRecent pressureValues currentPressureValueIndex 1 sz pressure fabsf average mostRecent caluculate pressure as difference between average and current acceleration float diff fabsf average acceleration.z..

How can I improve the performance of my custom OpenGL ES 2.0 depth texture generation?

http://stackoverflow.com/questions/6051237/how-can-i-improve-the-performance-of-my-custom-opengl-es-2-0-depth-texture-gener

more efficiently. By adjusting the triangle drawing as follows I was able to reduce overall rendering time by an average of 14 on top of the above described optimizations by switching to octagons from squares. The depth texture is now generated.. fragments to discard due to the octagons. This combined with a depth lookup texture for the sphere now leads to a 2 ms average rendering time on the iPad 1 for the depth texture generation for my test model. I consider that to be about as good as..

How to measure noise or sound and displays in dB(A) in iphone?

http://stackoverflow.com/questions/6183599/how-to-measure-noise-or-sound-and-displays-in-dba-in-iphone

this question If you use AVAudioPlayer you can use this method AVAudioPlayer avPlayer ... avPlayer play... avPlayer averagePowerForChannel 0 avPlayer averagePowerForChannel 1 From Apple's doc float averagePowerForChannel NSUInteger channelNumber.. you can use this method AVAudioPlayer avPlayer ... avPlayer play... avPlayer averagePowerForChannel 0 avPlayer averagePowerForChannel 1 From Apple's doc float averagePowerForChannel NSUInteger channelNumber Description Returns the average.. ... avPlayer play... avPlayer averagePowerForChannel 0 avPlayer averagePowerForChannel 1 From Apple's doc float averagePowerForChannel NSUInteger channelNumber Description Returns the average power for a given channel in decibels for the sound..

How does one compare one image to another to see if they are similar by a certain percentage, on the iPhone?

http://stackoverflow.com/questions/6488732/how-does-one-compare-one-image-to-another-to-see-if-they-are-similar-by-a-certai

through about 1 of the pixels in each image and either comparing them directly against each other or keeping a running average and then comparing the two average color values at the end. You can look at this answer for an idea of how to determine.. image and either comparing them directly against each other or keeping a running average and then comparing the two average color values at the end. You can look at this answer for an idea of how to determine the color of a pixel at a given position..

How to write a simple Ping method in Cocoa/Objective-C

http://stackoverflow.com/questions/798454/how-to-write-a-simple-ping-method-in-cocoa-objective-c

towards a solution using NSNetServices is this a good idea The method only needs to ping a few times and return the average and 1 if the host is down or unreachable. iphone objective c cocoa cocoa touch networking share improve this question..