Mediagate MG-25

Video

The unit supports most of the popular video formats, including MPEG, DivX, XviD, and even allows you to play VOB files ripped directly from a DVD.

Generally the video quality is excellent. The speed is smooth and no audio sync problems are introduced. Of course, this all depends on the encoding quality of the source, but video does look much better on a large TV screen than a computer monitor.

Standard playback controls (pause, FF, RW etc) are available, and work across most video formats. MPEG files only seem to allow forward and reverse increments of 10 seconds, whilst AVI files will play at speeds of 8x, 16x, and 32x.

Additional controls allow the brightness and contrast to be changed, as well as the screen format (4:3 pan-scan, 4:3 letterbox, and 16:9) and more interestingly, full control over the size of the video. This last feature means that you can manually trim any unwanted edges from video files.

A few problems exist with XviD playback, and this seems to be inherent with all media players that use the Sigma decoding chip. Files encoded with Quarter pixel or GMC will not operate, but the majority of XviD files should work perfectly. A few inconsistencies were noted with XviD files containing AC3 audio. In one case, a file would not playback at all, while similar files played fine. Additionally, the audio portion of an AVI would not play properly if it was encoded with the DivX ; ) Audio codec. This is not a usual codec, and was easily fixed using VirtualDub.

As already mentioned, AC3 audio will play via DivX, XviD, and VOB files. Using the coaxial digital cable this allows you to obtain full Dolby 5.1 and DTS surround sound. Very nice!

The MG25 does support subtitles, but only in the SRT format, and only for AVI files. It is possible to change the size and position of the titles on-the-fly, and multiple languages are supported. Subtitles are enabled by default, and it would have been better to allow this to be configurable (see note 6 at end).

Audio

The MG-25 plays MP3, Ogg Vorbis, and WMA audio files. The interface is the same as for video files, and you select tracks to play using the file browser. As with the rest of the media types, there is a ‘play all’ feature that allows all files to be played, including sub-directories. However, there is no randomise ability.

Playback controls are fairly limited, with the fast forward and reverse working in 10 second increments. Unfortunately it is not possible to leave the audio mode without stopping the currently playing track. This means you cannot play an MP3 file at the same time as viewing pictures.

No problems were experienced playing MP3 audio files, including VBR encoded files. WMA and Ogg Vorbis was not tested.

Pictures

The unit allows JPEG images to be displayed. These are selected using the standard file browser. A configuration setting allows thumbnails to be displayed by the side of the currently selected image. These are generated on-the-fly, and are sluggish. The loading of images is also very slow, and navigating through a large set of images quickly becomes a chore.

Once loaded, an image can be manipulated with the cursor keys moving it around the screen, and the volume keys enlarging and shrinking the image. Pressing ‘next chapter’ or ‘previous chapter’ displays the next or previous image. Pressing the F2 button rotates the image.

Playlists

The playlist mode allows any combination of media files to be tagged and then displayed in the order in which they were tagged. Images are shown for 10 seconds, whilst audio and video are viewed for the duration of the file. A randomise function does exist here.

The fundamental flaw with the playlist mode is that you cannot save a playlist. It is also not possible to import a pre-created playlist, such as a Winamp m3u file. This is a real shame as it limits the use of what would otherwise be a very handy feature.

Internals

The unit is firmware upgradeable, and several updates have already been made. No notes are included with new releases of the firmware, possibly due to the Korean origin of the player, and so it is hard to determine what progress has occurred.

Being the inquisitive type, and knowing that the unit makes use of the same Sigma chipset used in a lot of other players, a quick investigation into the firmware was made.

The motherboard contains an ARM processor, and runs a version of uClinux. The firmware contains many strings indicating that an Ethernet interface was available, at least in the development unit. Indeed, the Sigma chipset allows for an Ethernet interface and it is a shame that one was not included.

Digging further, the firmware appears to contain a section of code, probably the boot loader and main program, followed by a CramFS data block. CramFS is a Linux compressed filesystem often used on embedded system. Decoding this further shows a typical linux directory, along with many PNG and JPG files. These are all for the onscreen imagery.

Hopefully some enterprising individual will be able to take this further, and allow customisation of the firmware. As Linux is used as the operating system it should be possible to add all kinds of extra functionality. Who knows, maybe one day a version of MAME will be available!