smilingmiao

ffmpeg

Converting Audio into Different Formats / Sample Rates

Minimal example: transcode from MP3 to WMA:
ffmpeg -i input.mp3 output.wma

You can get the list of supported formats with:
ffmpeg -formats

You can get the list of installed codecs with:

smilingmiao

ffprobe -v quiet -print_format json -show_format -show_streams "lolwut.mp4" > "lolwut.mp4.json"

smilingmiao

private class Block<T> {
    let f : T
    init (_ f: T) { self.f = f }
}

extension NSTimer {
    static func xxx_scheduledTimerWithTimeInterval(ti: NSTimeInterval, block: ()->(), repeats: Bool) -> NSTimer {
        return self.scheduledTimerWithTimeInterval(ti, target:
            self, selector: "xxx_blcokInvoke:", userInfo: Block(block), repeats: repeats)
    }

smilingmiao

This notes is written by Sheldon. You can find me with #iOSBySheldon in Github, Youtube, Facebook, etc.

Need

Convert .mov/.MP4 to .gif

Reason

As a developer, I feel better to upload a short video when I create the pull request to show other viewers what I did in this PR. I tried .mov format directly got after finishing recording screen using Quicktime, however, gif offers preview in most web pages, and has smaller file size.

This is not limited to developer, anyone has this need can use this method to convert the files.

smilingmiao

//: A UIKit based Playground for presenting user interface
  
import UIKit
import PlaygroundSupport

extension Notification {
    struct UserInfoKey<ValueType>: Hashable {
        let key: String
    }