consoul said:
FF7 was three discs, so a 2GB stick would handle it no problem.
I guess FF8 is going to sell some 4GB sticks then.
Okay, I guess this thread is as good a place to put this.
Disclaimer: This is basically a lot of guesswork which I'm sure is quite faulty. It would be nice to get somebody who knows more about Final Fantasy VIII from a software engineering perspective to comment.
No matter how cheap large-capacity pro-duo sticks are getting, it's a good idea to save space if you can. Obviously, from the size of these initial downloads, the state of the Playstation emulator for PSP is that it reads straight disc images straight from the original discs. However, I think it would be a good idea in a future emulator update to allow for some PSP media engine-specific processing to come into play to enable AVC, AAC, and image compression formats within the emulation.
To that end, I decided to try a little armchair detective work to see how small FF8 could theoretically get with modern compression schemes that the PSP is capable of decoding.
After a bit of futzing around with MEGui and commandline avs scripts, I concatenated together the ending FMV of FF8 (on the CD it's split into three video files) and compressed it into an MPEG-4 AVC video with AAC audio (which the PSP natively supports)
I had good quality results on the sixteen minute file (keeping in mind a certain chunk of it is scrolling credits for better or worse) at a filesize of 36 megs (the three original MDEC codec FMV files total 320MB).
If you'd like to check this video out on your psp I uploaded it. It should work find on a PSP--it did the last time I checked, with recent firmware, but it has some odd header information which might futz it up for desktop playback.
Hit this link, unzip the files and put them within the appropriate AVC video folder structure on your PSP.
This works out to 2.25 megabytes per minute of FF8 FMV, although I did compress the audio at a high quality (around 130kbps VBR because I thought the ending music should have the bitrate to shine properly) so it could be even less than that. But let's assume that as a worse case. I estimate FF8's FMV to clock in at about 60 minutes total which gives us a total filesize of all the AVC-encoded FMV in the game at 135MB.
Furthermore, if FF8 is like FF7--and there's no reason to think otherwise. Audio and Video aside, the data contents are identical on each disc. That is to say, that all the assets and scenario sans FMV and "Eyes on Me" resides within each disc.
The fmv files on disc 4 take up exactly 373.63 MB. Let's round that down to 373.
The total size of the disc 4 cdrom is 576 MB.
Subtracting 373 from 576 gives us 203MB.
Add 203 to 135 and you have a downloadable game clocking in at 337MB. Big, but not outside reasonable memory stick capacity.
Further experiments.
A prerendered backdrop in FF8 is at 240p resolution and uses only 64 colours (doing a comparison A/B test in Photoshop) The image I used was a 320x240 still of a prerendered backdrop. The 2D image file format, TIM, on the Playstation is, by all indications, lossless and uncompressed, so I assumed file sizes would be analogous to a palleted BMP image.
Saved out to a 64 colour BMP file gives a size of: 172k
Now, let's try some lossless compression formats. The backdrop was of an organic, complex image without many like-colour areas for image compression formats, such as PNG, to save bits.
Saved out to a 64 colour GIF file gives us a size of: 41.7k (24% of original size)
Saved out to a 64 colour PNG file gives us a size of 39.3k (22.9% of original size)
If a system was implemented to store backdrops as PNG files, we could decrease the field image data to 22.9% its original size, which is considerable.
How much of the game data is prerendered backdrop? Now we get into conjecture, but here's a few clues:
A backdrop is not going to be a 320x240 image most of the time. It's going to be larger (say a long corridor that the camera pans down when you run from right to left) so let's say the average backdrop is 30% larger than the area onscreen at any time, so 172k * 1.3 = 223.6k per backdrop
A backdrop may have some small "foredrop" elements that are composited in front of the 3D models of your characters (tables, lampposts, etc) so let's make it 40% larger to include these images and their transparency masks. 172k * 1.4 = 240k per backdrop. I consider this fairly conservative.
But how many backdrops are there in FF8? Well there are exactly 579 prerendered backdrops. I know this because the Final Fantasy VIII: Ultimania book lists each and every one of them with an accompanying thumbnail in the best chronological order possible.
579 * 240k / 1024 = 135.7MB of backdrop image data on the disc.
Subtract 135.7 from 203 and you have 67MB for 3D models, worldmap, BGM, 3D battle sets, animation, textures, and scenario. This may sound too small, but keep in mind that the Ocarina of Time is only 32MB.
So, let's take that 135.7MB of 2D backdrop data, and apply the PNG compression to it.
22.9% of 135.7MB = 31.1MB.
So, to sum up.
AVC-encoded FMV = 135MB
PNG-compressed backdrops = 31.1MB
Other data = 67MB
This gives us a total of 233MB.
What are your thoughts?