Suggested Content formats and sizes for CMX

Contents

• Wallpapers
• Ringtones
• Videos

Wallpapers

Wallpapers can be automatically resized by CMX into the correct size for the phone. For this to work most effectively, the original image should be approximately 640w x 480h. There is no reason to upload an image larger than this, and by default any image larger than this will be shrunk to size. For maximum compatibility with phones, we suggest JPEG files in 24-bit colour.

Animated wallpaper can be created using Animated GIF files. Again the image should be no more than 640w x 480h. Note that not all phones will display animated wallpapers, and it's hard to know whether a specific phone will support animated wallpapers.

Known issues:

• JPEG files in greyscale or black and white are not supported by phones. Providing full colour source files will prevent any issues arising.

Ringtones

There is a wide variety of ringtones, coming under the general categories below. These must be treated in two sections.

Monophonic ringtones that are delivered by SMS. These include imelody tones and nokia RTPL/RTTTL tones. There are no specific compatibility issues with these, and any valid files should work on all phones.

Polyphonic or Realtones, delivered by WAPPush. It is recommended that you provide and upload as many ringtone formats as possible into CMX, as this allows us to obtain the best format for any specific phone. To cover as many phones as possible, you must upload a MIDI file with a maximum of 16-note polyphony, but 4-note is recommended. To optimally serve content to all phones we suggest that MIDI, SMAF/MMF, SP-MIDI and MP3 files be uploaded. Optionally AAC files encoded within 3gpp wrappers may be uploaded, as may WAV files.

We suggest that ringtones are kept under 30s long, especially if they are WAV or MP3 encoded, as these formats can get very large very quickly. The largest ringtones should be about 100k.

MP3 files should be recorded in mono (as most phones will not benefit from stereo ringtones), and should be encoded at a maximum of 128kbps, as some phones cannot play a higher bitrate.

Known issues:

• Some phones have been limited by the network operators to not accept specific content types. MP3 files are most commonly affected by this. If a file works on one phone on a specific network, it may not work on another phone on a different network.
• Some phones may be capable of playing fewer than 16 notes concurrently. This may affect the sound quality of polyphonic midi files. This limitation can be resolved by using sp-midi formatted ringtones, which downgrade gracefully if the phone does not support enough notes.
• Some ringtones (especially sp-midi and MMF/SMAF) must be created professionally to maintain small file sizes and high quality. Automated converters do not do this job effectivley.
• WAV or wave format files are not recommended, as they have a very large filesize, and many sub-versions exist, not all of which will be compatible with all phones. It is very hard to tell if any specific WAV file is compatible with any specific phone.
• It is possible to have files called .MP3 which are not MP3 files. Please check that the file is formatted as an 'MPEG 1 Layer 3 Audio file' in your sound editing program before uploading. Your PC may be able to play these files, but phones are more picky on which files they can play.

Videos

Video formats within CMX. We suggest that you create 3gpp-formatted video, as this is available on the largest number of phones. We recommend that content should be limited to 30s. If you are interested in serving longer videos, we suggest using Video Short Codes or streaming the content to the phone. Please contact us for more information. The following are general guides: you will get better results by tinkering with the values slightly to get the best image and sound quality for the smallest filesize.

Although we have suggested maximum filesizes for both 3G and 2G phones, there is no simple way to find out how content is being accessed. It is possibly more useful to create both high quality and low quality services, so that end users with 2G phones do not have a very long wait, and end users with 3G phones have an enhanced user experience.

It is also possible to format in the PacketVideo or mpeg4 Visual Simple Profile 0 format. If you're using PacketVideo, we suggest using AAC audio, as this is usually available on phones which support PacketVideo. As these viewers are generally not available on every phone, we do not recommend that these are used, as there is no way to decide if a phone supports the video format until the end user gets an error message.

Known issues:

• Some phones have been limited by the network operators to not accept specific content types. Video files may be affected in this manner. It is also often required to install third-party software to view some content formats on some phones, and different operators may install different software.
• Sometimes, the phone will go out of reception half-way through a download. This can lead to a variety of errors, in general, none of which are the responsibility of CMX.