Capturing Video on J2ME devices

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Introduction

The Mobile Media API extends the functionality of the J2ME platform by providing audio, video, and other time-based multimedia support to resource-constrained devices. As a simple and lightweight optional package, it gives Java developers access to native multimedia services available on a given device.

Source Code for Capturing Video on J2ME devices

The Manager class is the static factory class in the MMAPI. The createPlayer() method is the factory method used to create Player instances.

The following function creates a Player instance. Because J2ME compatibility between different manufacturers can differ we trying to create the player through several parameters.
If the mobile phone is equipped with several cameras, you can specify which camera you want to use through the int camera parameter.

private final Player getCamera(int camera) { try { return Manager.createPlayer("capture://devcam" + camera); } catch (Exception ex) { try { return Manager.createPlayer("capture://image"); } catch (Exception ex1) { try { return Manager.createPlayer("capture://video"); } catch (Exception ex2) { System.out.println("Get camera device failed!"); return null; } } } }

The video coming from the camera can be displayed on the screen either as an Item in a Form or as part of a Canvas. A VideoControl makes this possible. To get a VideoControl, just ask the Player for it:

vc = (VideoControl) player.getControl("VideoControl");

If you wish to show the video coming from the camera in a Canvas, initialize the VideoControl, then set the size and location of the video in the Canvas, and then make the video visible.

vc.initDisplayMode(VideoControl.USE_DIRECT_VIDEO, this); vc.setDisplayLocation(0, 0); vc.setDisplaySize(getWidth(), getHeight()); vc.setVisible(true); player.start();

Once the video camera is shown on the device, capturing an image is easy. All you need to do is call VideoControl's getSnapshot() and pass an image type, or null for the default type, PNG.
Also you can find the image types that are supported by your mobile phone .The video.snapshot.encodings system property contain a whitespace-delimited list with these values.

The getSnapshot() method returns an array of bytes, which is the image data in the format you requested. What you do at this point is up to you: you might save the bytes in a record store, send them to a server, or create an Image from them.

imgBytes = vc.getSnapshot("encoding=jpeg"/*+videoOptions*/);

Through the videoOption you can specify the width and height of the captured image. For example videoOption =”&width=640&height=480”.

Note:Not all mobile devices support these parameters (width & height).

License

This article, along with any associated source code and files, is licensed under The Intelliproject Open License (IPOL)

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