Apple Grandia Data

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Apple Grandia Data (Apple グランディアデータ) is a video format used exclusively on the 1997 Sega Saturn game Grandia, developed by Game Arts. It's an unusual format based on the Apple QuickTime container format, and it doesn't resemble any container used by any other game on the system.

The container is described in the moov -> trak -> mdia -> hdlr atom as "Apple ビデオ・メディア・ハング" (Apple video media hang?), and within moov -> trak -> mdia -> minf -> hdlr as "Apple グランディアデータ" (Apple Grandia data).

Video

The game's decoder renders the video at 352x480 using one of the Saturn's 480i video modes. The video is letterboxed 16:9 presented at 352x360 within that frame. The real resolution, determined by eliminating duplicate lines, appears to be 352x144; that adds up to vertical scaling of 2.5x.

The video codec hasn't yet been identified. It has qualities which don't resemble any of the codecs typically used on the Saturn, which makes identifying it hard. The video has clearly visible 8x8 DCT blocks and ringing artifacts which don't resemble either Cinepak or Duck TrueMotion 1, the two formats most commonly used by software decoders on the hardware. This suggests that it could be some variant of MPEG 1 codec, decoded using software.

Display resolution Stored resolution
Grandia video data screenshot - native resolution.png
Grandia video data screenshot - original resolution.png

The data contained within the video track is misidentified, possibly because there are no standard values for the real codec in use.

Field Metadata location Fake value Real value
Width moov -> trak -> tkhd 320 352
Height moov -> trak -> tkhd 240 144
Codec moov -> trak -> mdia -> minf -> stbl -> stsd cvid (Cinepak)  ???

Audio

The audio data does not appear to be described by any of the QuickTime atoms. The audio format is CRI ADX ADPCM. Each video uses stereo audio encoded at 22050Hz using the ADX version 3 format. This audio is standard, and can be decoded by any ADX decoder.