I have this one and to be honest: It flocking rocks.
BUT BEWARE: it DOES NOT play Mp3 files.You have to convert them first into gbs files which the movie player understands.Or the better way would be WAV which is also supported and gives you great sound.the converted gbs sound files are compressed(at least 1:8) so the sound isn't as great as in WAV but the filesize is much smaller.I just use WAV files for my songs cause they have CD quality via headphones(I'm using a 1GB card as well btw).
The great thing about the "GBA Movie Player" is that he has other neat feauters too which I'll explain now:
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Play sound files in gbs or WAV format.The packed-in PC software converts every known sound format into gbs.Here's the official statement:
Music is converted into a GBS file after conversion. The GBS file and uncompressed WAV files can be played on the GBA/GBA SP. Supported wav file: Sample rate<=48KHz;Sample bit rate: 8 bit or 16 bit; Channeling: Stereo or mono.
Support for LRC synchronous lyrics files. After putting the LRC file (With the same name as the corresponding GBS or WAV file) and the GBS or WAV file to the same directory on your the CF Card, the synchronous lyrics can be displayed on the GBA/GBA SP while music is playing.
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Watch movies in gbm format. The PC software converts all the most used video files into GBM files.You can also set different adjustments with the software(sharpness etc).After some trying out I managed to get a good picture out of the Movie Player which can be a bit blocky at dark scenes but overall:Good not great....I'm satisfied.
If you are a picture-quality freak you better get the "Play Yan" which has better pic-quality but lacks all the other features the GBAMP has(exept MP3 which Play Yan also supports).Also "PLay Yan" cost about three times more and comes ONLY with japanese software.
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images support(photos,pictures etc):
The GBA Movie Player supports uncompressed BMP format image. It also has image magnification tools and lantern slideshow playback functions. Supported BMP formats are: 32 bit and 24 bit true color, 16 bit GBA true color, 256 colors and gray scale, 16 colors, 4 colors and 2 colors B&W.
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e-book feature: Well,not exatly since it "only" supports txt files which is OK for me.Just put them on the card and let the reading begin.
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NES emulation feature: You will be able to play NES/Famicom games which are smaller than 256kb with the GBAMp which is really a nice feature.
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Here is the official website and
here is an awesome forum for all your info needs.
Overall I highly recommend the GBAMP cause it has some really nice features and pic-quality looks pretty good(especialy on DS).