Difference between revisions of "IOS"

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(→‎Related projects: update link to ogv.js)
(→‎Building: updates)
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== Building ==
 
== Building ==
  
Experimental work in progress script to build the libraries to .framework bundles that can be easily linked to in an Xcode project: https://github.com/brion/OgvKit
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Experimental work in progress script to build the libraries and wrap them with a high-level Objective-C interface that can be easily dropped into in an Xcode project: https://github.com/brion/OgvKit
 +
 
 +
Build the C libraries first in a terminal:
 +
* Requires autoconf, automake, and libtool; can be installed via homebrew.
 +
* Run 'make' to build all C libraries
 +
 
 +
Once the C libs are built, you can fire up the OgvKit or OgvDemo projects in Xcode and run/test them directly:
 +
* OgvKit: Xcode project with the Obj-C wrapper built as a static library
 +
* OgvDemo: Xcode project with sample app, imports the OgvKit project
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=== Notes ===
 
=== Notes ===
  
* uses existing autoconf build infrastructure; scripts wrap autogen.sh with appropriate settings, then combine the build products into framework bundles
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* CLI makefile builds each library for armv7, armv7s, arm64 for devices and i386, x86_64 for simulator, then combines them to multi-arch universal binaries
* framework bundles each contain a 'fat binary' library with armv7, armv7s, arm64 for devices and i386, x86_64 for simulator, plus a subdirectory with the C headers
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* wrapper library links to and encapsulates the low-level C libraries, so this should be usable in future Swift projects as well as Obj-C
 
* libtheora
 
* libtheora
 
** Must pass --disable-asm, as the asm code doesn't build for iOS (yet?) [https://gist.github.com/brion/7345164 errs]
 
** Must pass --disable-asm, as the asm code doesn't build for iOS (yet?) [https://gist.github.com/brion/7345164 errs]
 +
** doesn't build with iOS 7.1 SDK from the current git mirror -- need to get git mirror fixed or change build system to fetch from svn
  
 
== Performance ==
 
== Performance ==

Revision as of 23:50, 25 June 2014

At least libogg, libvorbis, and libtheora build and run on iOS without modification in their current incarnations.

Building

Experimental work in progress script to build the libraries and wrap them with a high-level Objective-C interface that can be easily dropped into in an Xcode project: https://github.com/brion/OgvKit

Build the C libraries first in a terminal:

  • Requires autoconf, automake, and libtool; can be installed via homebrew.
  • Run 'make' to build all C libraries

Once the C libs are built, you can fire up the OgvKit or OgvDemo projects in Xcode and run/test them directly:

  • OgvKit: Xcode project with the Obj-C wrapper built as a static library
  • OgvDemo: Xcode project with sample app, imports the OgvKit project


Notes

  • CLI makefile builds each library for armv7, armv7s, arm64 for devices and i386, x86_64 for simulator, then combines them to multi-arch universal binaries
  • wrapper library links to and encapsulates the low-level C libraries, so this should be usable in future Swift projects as well as Obj-C
  • libtheora
    • Must pass --disable-asm, as the asm code doesn't build for iOS (yet?) errs
    • doesn't build with iOS 7.1 SDK from the current git mirror -- need to get git mirror fixed or change build system to fetch from svn

Performance

See preliminary benchmarks at https://github.com/brion/OgvKit/wiki/Device-notes

OS integration

Native codecs

NO

iOS's native media framework is AVFoundation, which unfortunately is not extensible with codec or file type plugins. :(

It should be possible for an Obj-C wrapper library to use the same audio and video buffer types for input/output as AVFoundation does, however, which will make it easier to hook them up together for transcoding or live encoding from the camera.

File type handler

YES

It is possible for an app that plays Ogg media to register its file types with the system, allowing other apps that may download files (Safari, Mail, Dropbox, etc) to prompt to open them in the player.

I have implemented an early test of this in OgvKit demo player; it works but, for instance Safari will download the entire file and then hand it off to the player, so you cannot play during the download.

URL handler

YES, BUT

It is possible for an app that plays Ogg media to register a URL handler, which would allow other apps or web content to launch the player. A remote URL could be included as a parameter on that URL, allowing apps or web content to hand off something to download-and-play progressively.

Unfortunately you can't do something like register for 'http[s]://*/*.ogv' -- you can only register a scheme such as 'x-ogvkit-player'. So you can't accept arbitrary HTTP or HTTPS links; the calling app or web content needs to know your app-specific URL scheme.

Related projects

  • ogv.js JavaScript codec works in iOS Safari
  • MobileVLCKit wraps many codecs including the main Xiph ones, and has a high-level player interface