Best And worst Quality FMV (Streaming video) on the Sega CD?

[kool kitty89]

Sonic CD and Joe Montana came out with in weeks of each other. SOA already done the deal and was using the new Codec in the spring on 1993. They really should have gone to SEGA Japan and say we've got this much better codec, use it for the FMV in Sonic . Mind you knowing Sonic Team and SEGA Japan they were too pigheaded to admit SOA had the better codec.

And, again, there were still good alternatives prior to cinepak. (and ones that should have worked much better with cartoon style animation than the live action video they were largely used for -compression was using derivatives of the common LZ type lossless schemes, something that would work far better with drawn animation, especially with some optimized preprocessing)

It wasn't just the smoothness or the animation , it was that so much of the detail was completely cut out too. If one look at Devastator original source Video a lot of the detail was still kept in the Mega CD FMV, in the Sonic CD FMV intro, loads of detail is cut out

Yes, that's true too. Part of it seems to just be from posterizing to 16 colors (same for Road Avenger or Keio), but then there's the extreme lack of dithering (dithering would better preserve detail -Road Avenger used that very minimally, but Tenbu MCD Special used it much more heavily -the framerate is poor, but the per-frame quality is quite good for 16 color video -Tenka Fubu used multiple palettes along with dithering).

Sonic CD is not just converted to low color from the source video though. If you compare the 2 back to back, it's much more like Time Gal (if not more extreme) where much of the animation was heavily modified if not completely redrawn by hand (and a lot of it really looks like they redrew it -especially Sonic), and that implies a LOT of painstaking work was involved. That implies that SoA wasted time and resources to optimize video for a limited format where a decently optimized conversion program probably could have done a better job preserving the original animation (even something on the level of Road Avenger's heavy posterization should have looked better -let alone using a higher dithering threshold more like Tenbu, let alone using added palettes like Tenka Fubu, Dragon's Lair, etc)

That's certainly one area even Night Trap and Sewer Shark's formats would have helped: lower spacial resolution (and screen size), but use of multiple palettes and dithering to preserve more detail (at the expense of a grainly look and loss of sharp/smooth edges), and drawn animation would tend to work better there too. (same reason most drawn animation looks better than live action of similar technical quality -more limited colors/shading/etc-)

Also Note: one plus for uncompressed video is that complex dithering methods are practical without trade-offs of difficult compression; lossless schemes tend to compress better with limited dithering thresholds (heavier posterization -especially for simple RLE compression) and/or use of more limited ordered dithering patterns. (the latter is also the case for Cinepak, as pattern block dithering caters very nicely to the way cinepak works)

Mind you FMV intro is great for a couple of viewings, pretty much pointless afterwards .

First impressions and "wow factor" are certainly a big deal though, both in terms of bringing the system home (especially had it been pack-in) and seeing it in store kiosks.

The bigger let-downs for me, was Sonic CD made no real use or really took advantage with the Mega CD ASIC or PCM chips In-game . When every level or at least every boss battle should have been an showcase for the ASIC chip. It's pretty sh8t and embarrassing that ports of Chuck Rock II, Puggsy were a better showcase for the Mega CD ASIC chip in Game , than Sonic CD.

Yes, it should at least have been on the level of showcase that Super Mario World was (every boss used mode 7, some of the castle demolition sequences used it too iirc).

OTOH, they could have done something like given sonic more speech (including in SFX), and we all know the sort of complaints emerged once he started talking later on. (as it is, he technically does speak, but in an extremely limited manner)
Heh, if SoJ HAD done that, I wonder if SoA would have re-dubbed it with Jaleel White.

[Team Andromeda]

And, again, there were still good alternatives prior to cinepak

yes but given the deal was done, Sonic CD should have used cinepak.

If you compare the 2 back to back, it's much more like Time Gal

Time Gal is not really a great example . The FMV parts in Time Gal (intro) is better for starters and the steaming use in Game is not only in a far bigger window, bit also much clearer and colourful. Though Chuck Rock II totally out classed both.

First impressions and "wow factor" are certainly a big deal though, both in terms of bringing the system home

There's always a wow factor, but I think most would have wanted to see a real show case for the ASIC chip myself .

(every boss used mode 7, some of the castle demolition sequences used it too iirc)

Yes now that's what I mean, and what I'm talking about .

they could have done something like given sonic more speech (including in SFX)

I'm sure more speech was recorded for the game, but never ever used .

[kool kitty89]

yes but given the deal was done, Sonic CD should have used cinepak.

If SoJ had been willing to push for a better format for the initial release, one of the earlier formats would be more applicable though.

Time Gal is not really a great example . The FMV parts in Time Gal (intro) is better for starters and the steaming use in Game is not only in a far bigger window, bit also much clearer and colourful. Though Chuck Rock II totally out classed both.

The FMV intro is rather nicely dithered (and seems to be a direct conversion of the laserdisc animation), but in-game it's edited very much like Sonic (very low color, extremely posterized, and pixel-art cartoonish). The really odd thing about Time Gal is the horribly slow framerate for the screen size (the resolution is almost the same as Sonic CD -mostly just a different aspect ratio-). It's as slow as Tenbu (or the wolf team logo) but at a much smaller resolution.
Even without compression, 192x160 16 color video should have easily been the 7.5 FPS of Road Avenger or 8 FPS of Sonic CD (and had more than enough room for Sonic quality 32 kHz audio) or if they'd been willing to cut the screen size slightly and go with 16 kHz audio, they could have boosted it to 10 FPS. (not to mention what would have been possible with compression) Albeit given the relatively low motion animation style of Time Gal (somewhat like Road Avenger), 7.5/8FPS probably would have been decent.

Also note that if the source animation was 30 or 60 Hz video, then 7.5 and 10 FPS would tend to work well (both direct divisions of the source framerate), but if it was 24 FPS, 8 or 12 FPS would be better suited. (dropping to non integer divisions of the source framerate tends to result in stuttering)

Time Gal in-game and Sonic both look rather like what happened with Dragon's lair on the Amiga/ST/PC on floppy disk. (not the CD-ROM PC release -which was more like the Sega CD one, but with better color) It looks like simplistic pixel art derivatives of the original animation rather than optimized digitized/reformatted conversions from the source material. (Road Avenger seems to be 100% converted from the original animation, as does the attract mode of Time Gal)


As for Chuck Rock (and BC Racers). The thing it has going for it is being totally designed as pixel art for the system and either compressed or not FMV at all (realtime tile+sprite animation with streaming animation updates off CD) with relatively smooth framerate as a result. (though limited action on-screen) It's a bit like some PC adventure games (especially Lucas Arts) in that respect, but lower-budget looking (and more limited in general).
Lunar 2 and Popful mail use similar hybrid cutscene engines, but to much better effect in terms of art quality and detail. (Chuck Rock certainly does what's intended though, and the animation does fit the art style of the game)
And I certainly can't complain about Chuck Rock being degraded from a higher quality source.

[bgvanbur]

So with all this talk about Sonic CD FMV should have used Cinepak, I did the conversion that never was. I used TMEE's Sonic CD viewer code as a reference to decode the OPN.STM file and my work in progress Cinepak encoder to make the Cinepak version. I also modified the V1.2 Cinepak code to allow 32KHz playback. Given the original OPN.STM was 14014464 bytes, the PCM data is 3014656 bytes, and my generated Cinepak data at 7081420 bytes, this yielded my Cinepak image data 37% the size of the the original OPN.STM image data.

http://dl.dropbox.com/u/26821164/OPN.ISO

[kool kitty89]

So with all this talk about Sonic CD FMV should have used Cinepak, I did the conversion that never was. I used TMEE's Sonic CD viewer code as a reference to decode the OPN.STM file and my work in progress Cinepak encoder to make the Cinepak version. I also modified the V1.2 Cinepak code to allow 32KHz playback. Given the original OPN.STM was 14014464 bytes, the PCM data is 3014656 bytes, and my generated Cinepak data at 7081420 bytes, this yielded my Cinepak image data 37% the size of the the original OPN.STM image data.

http://dl.dropbox.com/u/26821164/OPN.ISO

At first I thought you meant you re-encoded the intro into Cinepak from one of the higher quality sources (namely the Sonic Gems collection one -MPEG2 I think- or even the Saturn's TrueMotion or PC Indeo versions), but you just compressed the exiting file to a smaller size.
Still a neat comparison if anything. (and not having the boarder on the screen makes it look better -which is usually the case IMO, one of the positive points of the way SNES Doom was handled)

This is using Cinepak losslessly, right? (since the format itself is technically lossless if the encoder applies no additional filtering to increase compression -or if preprocessingis done to the same effect)



On another note:
if anyone ever was to make a Sega CD demo for Sonic CD in Cinepak from a higher quality source, the Indeo 3 PC version (not the later indeo 4 re-release with more MPEG-like artifacts) might be a good starting point if anyone ever did do that given the existing macroblock artifacts would probably cater well to trancoding to Sega CD Cinepak, and because the PC AVI files are easily accessible from the disc directory (so it shouldn't be horribly difficult to capture each decompressed frame losslessly -assuming there's no usable video editing software supporting Indeo 3). Of course, that also means using the same 256x112 screen size as the Sega CD original since the PC version (unlike Jam and Gems) used that same resolution.
You'd still probably need some additional filtering on the encoder to manage a consistent compression ratio (and bitrate) unless the initial conversion to 16 color (or 4 paletted) video was enough to allow the desired compression with Sega CD Cinepak. (rather doubtful, though that source is only 15 FPS, so maybe even the more poorly compressing frames wouldn't exceed the bandwidth)

What's also interesting is that both the Indeo 3 and 4 versions are in highcolor (if not Truecolor) but the game itself runs in 256 colors and downsamples to that with some limited realtime dithering. (not sure why they didn't use a format that natively supported 256 color paletted modes given that should have resulted in higher quality when actually viewed in game -and there doesn't seem to be a highcolor option in-game) Also odd is that only the intro was ever re-encoded, the endings (and other sequences) were left in Indeo 3 for whatever reason.
Also interesting is that relatively high quality audio was used for the PC version with 22 kHz 16-bit uncompressed stereo (taking up 705 kbps of the total 2457 bitrate -2x CD rate for mode 1 data).

[kool kitty89]

I decided to do some simple conversions and comparisons of some screenshots of the indeo 3 rendition and MCD (as well as simple 256 and 16 color downsampled exampled made using irfanview -with no added dithering). Interestingly, the conversion to 256 colors shows very few visible artifacts (in spite of dropping from ~3000 and ~6600 in these 2 examples) though some indeo 4 screenshots didn't fare as well (apparently due to the different types of artifacts native to that format -the native color counts also tended to be much higher than indeo 3), and I didn't bother including those indeo 4 shots in my group of attachments.

The intro example was chosen as it's recognizable, shows sonic as well as a sizable background, and because it's one example where the redrawn Sega CD pixel art doesn't differ hugely from the source. (some parts of the animation look totally different -like the scene towards the beginning when Sonic is zoomed-in facing the screen while running)

I also noticed something odd with the AVI file. The video is 1:30 long and the details listed in the file properties indicates a full 2x CD bitrate, but the file itself is only 17.6 MB (which would only be 60 seconds at 2x or 200 kB/s for 1:30), so I'm not sure what's going on there. (oddly enough, the indeo 4 version is 18.9 MB)


Edit: see previous post for the final 2 images. (apparently there's a 5 picture limit to attachments)
And I added the example of the dramatically different MCD and original (in this case from the indeo 4 version) animation sequence I mentioned above. (that's just about the same time in the same scene, or as close as I could get when trying to compare)


I also realized that one thing that really bothers me in Time Gal's in-game animation (more so than Sonic CD) is the very hard (nearly always black) outlines for the redrawn pixelart derivatives of animation (unlike Sonic which, which at least doesn't use hard black outlines for much of the animation -which also allows for better color optimization in scenes without any notable black areas). Still, I prefer the directly converted (non re-drawn -or more moderately retouched) examples over either of the pixel-art-ish examples. (including Time Gal's intro and Road Avenger)

[bgvanbur]

This is using Cinepak losslessly, right? (since the format itself is technically lossless if the encoder applies no additional filtering to increase compression -or if preprocessingis done to the same effect)

Yeah, what I provided was a lossless copy of the Sega CD version of the movie. I wanted to add another file format to my Sega CD decoding extraction script.

I looked at the Sonic CD for PC files, and I can read and extract the Indeo 3 files but there seems to be no open source decoders for Indeo 4. I am thinking about reencoding GOODEND1.AVI as Cinepak for Sega, since it will help me further develop my cinepak tools (I still need to enhance my image to sega VDP conversion). Even though Sega warned about cinepak movies over 3-4 minutes, it seems this one would be within the limits.

About the 2x bitrate, perhaps it is reporting the required bitrate. It requires ~1.5x but since CD players usually come in integer multiples, it requires a 2x CD player.

And a note about Cinepak, it does not require a constant bitrate since it fills up the allocated RAM with as many sectors as soon as possible, it can properly handle variable bitrates (obviously you still need to keep within the 1x bit rate for the most part). So you can read a 0x4000 byte audio chunk around once a second without changing the image frame rate due to this buffering. However, it seems the Sega Cinepak encoder tried to maintain a common bitrate since it encodes sequential frames at the same exact size, whereas my Cinepak encoder optimizes for size (which is why I can losslessly reencode existing Cinepak for Sega files at 3% to 50% their original size). And when using these smaller Cinepak files with a bitrate smaller than 1x will have the Sega CD red read LED blink on and off since it doesn't need to constantly read the CD.

[Da_Shocker]

13 pages to discuss the technical merits of the FMV on the SCD? It doesn't matter what codec what codec was used it still looked bad. It's like trying to kill oneself with a 9mm or a .45. The 45 packs more of a wallop but a head shot will off you either way.

[Team Andromeda]

13 pages to discuss the technical merits of the FMV on the SCD? It doesn't matter what codec what codec was used it still looked bad. It's like trying to kill oneself with a 9mm or a .45. The 45 packs more of a wallop but a head shot will off you either way.

I usually agree with a lot of what you said, but the FMV in Adv Of Batman & Robin, Cadillac and Dinosaurs, Fifa looks (not is) better quality and in bigger windows than a lot of the launch Saturn FMV imo

[bgvanbur]

13 pages to discuss the technical merits of the FMV on the SCD?

Obviously this thread isn't for you since you already decided all Sega CD FMV is of the worst quality.

[Da_Shocker]

Obviously this thread isn't for you since you already decided all Sega CD FMV is of the worst quality.

It really didn't look good back in 92 and it sure as hell doesn't look good now.

[kool kitty89]

Yeah, what I provided was a lossless copy of the Sega CD version of the movie. I wanted to add another file format to my Sega CD decoding extraction script.

I looked at the Sonic CD for PC files, and I can read and extract the Indeo 3 files but there seems to be no open source decoders for Indeo 4. I am thinking about reencoding GOODEND1.AVI as Cinepak for Sega, since it will help me further develop my cinepak tools (I still need to enhance my image to sega VDP conversion). Even though Sega warned about cinepak movies over 3-4 minutes, it seems this one would be within the limits.

Do you have a copy of the indeo 3 version of the intro sequence? (it seems to have only been used on early releases -probably just the pre-directX versions)

And, yes, Indeo 4 seems to be a bit limited/illusive in support in general (Indeo 3 is playable through windows media player, quicktime, VLC, and I think Realplayer by default, but 4 is pretty limited -comes with media player in XP and prior iirc, but it seems vista requires installation of a legacy codec pack -which I ended up doing).
In the context of using anything as a source for Sega CD cinepak demos, again, the Indeo 3 examples would probably be better suited anyway due to the existing conversion/compression artifacts matching better to Cinepak. (vs Indeo 4 which has different artifacts which would be more likely to be compounded by conversion to Sega Cinepak)
Of course, if you used the MPEG-2 version (or perhaps JAM's version), you'd have an even higher quality/resolution copy to work with. (at least higher resolution for the Saturn's case -though if it's Truemotion 2, it might be higher quality than Indeo 4 too, even at the higher resolution)

About the 2x bitrate, perhaps it is reporting the required bitrate. It requires ~1.5x but since CD players usually come in integer multiples, it requires a 2x CD player.

I guess that would make sense given the relatively tight space (pretty much a full 72 minute disc with all the CD-DA tracks included).

And a note about Cinepak, it does not require a constant bitrate since it fills up the allocated RAM with as many sectors as soon as possible, it can properly handle variable bitrates (obviously you still need to keep within the 1x bit rate for the most part). So you can read a 0x4000 byte audio chunk around once a second without changing the image frame rate due to this buffering. However, it seems the Sega Cinepak encoder tried to maintain a common bitrate since it encodes sequential frames at the same exact size, whereas my Cinepak encoder optimizes for size (which is why I can losslessly reencode existing Cinepak for Sega files at 3% to 50% their original size). And when using these smaller Cinepak files with a bitrate smaller than 1x will have the Sega CD red read LED blink on and off since it doesn't need to constantly read the CD.

I doubt any Sega CD game developers would really want to sacrifice video quality to save space though. (albeit a moderately variable video compressiondatarate -that still conforms reasonably to the average/peak bitrate- could result in more optimized compression per-frame -and from what I've read, variable frame/data packet sizes were used to some extent for Cinepak and SGA -not really for the uncompressed examples though)

OTOH, Sonic 3D Blast's animation was almost certainly optimized to save space (given it's in ROM).

Obviously this thread isn't for you since you already decided all Sega CD FMV is of the worst quality.

What's interesting to note is that some contemporary PC and 3DO games (on technically much more multimedia-capable hardware) actually managed worse than on the MCD.

Albeit, one example that immediately comes to mind was converted even more poorly to the Sega CD, Rebel Assault. I realize that most of the in-game portions used realtime scrolling/panning that thus required considerable overscan (and thus large video frames), but that doesn't explain why parts of the cutscenes look so poor (even for 1x rate 256 color cinepak). They seem to have used a fixed 256 color palette, so that may be one of the bigger problems for quality (not sure why they didn't just reserve a smaller chunk of the palette for fixed colors used for sprites/game objects) and that problem is far more severe in the Sega CD example, which doesn't even make use of hardware sprites but renders to the same 16 color layer as the FMV. (sega CD also has severe tearing and stuttering framerate) Both look best in the space scenes by far.
The 3DO version seems to be a direct port of the PC version given similar artifacts and color issues. (and the use of 1 disc, so not re-encoded for 2x rate, let alone highcolor/truecolor cinepak)

It seems like they really would have been better off to drop the resolution (and thus compression ratio) of the game to reduce the artifacts (among other optimization -like efficient use of palettes) and either make do with a smaller screen size, or scale up (namely use double wide and/or tall pixels, or other integer scaled values -little overhead and no scaling artifacts).
Even if single buffered, the tearing shouldn't have been that bad on the Sega CD if they'd clipped for more vblank time (given the screen size/orientation).

Honestly, I find many (if not all) of the barely compressed or uncompressed FMV examples to be better looking than Rebel Assault on the Sega CD (sans the uncompressed/buffer animated death scenes). Sewer Shark looks better for the most part IMO (smaller screen size for sure, but much smoother framerate, more/better color and no nasty compression/conversion artifacts -at least compared to Assault). The only game on the MCD I can say has universally worse quality video (at least IMO) would have to be Terminator. (looks like uncompressed 16 color video using a fixed color palette)


As I mentioned in the other thread, it seems like Lucas Arts may have used their own format derived from PC/Mac Cinepak (assuming that's what the PC/Mac/3DO versions of Rebel Assault used) for the Sega CD conversion. That implementation obviously didn't work out very well quality wise (albeit the results on PC/Mac/3DO weren't great either), but I wonder if there was more merit to a (more or less) direct adaptation of "real" Cinepak to the MCD. (given the use of only 16 colors -apparently a fixed palette at that, large screen sizes -especially with overscan, and tearing issues, Rebel Assault really isn't a good example for that format one way or the other -just an example of how poorly it could be implemented) I'm not sure what the framerate issues are due to. (if they're issues with CPU decompression time, that would point to it being an ill-suited format or simply poorly coded, but the slowdown could easily be due to variable compression ratio instead -something Dune and Silpheed also exhibit)

[bgvanbur]

I don't have the Indeo 3 version of the intro movie.

Looking at the Sega CD good ending and the PC good ending, there is obvious color and brightness change. The Sega CD one is much more colorful and in my opinion the colors on the Sega CD are much better. When I started to convert the PC version to the VDP palette, the ugly colors looked bad (so the conversion from this source seems pointless to me since it has less audio quality, worse colors despite having more, and just a better frame rate). Attached are two similar frames from each version.

In terms of bad FMV, parts of the Power Rangers were bad since they were converting existing footage to the Sega VDP and I remember a point where the people had green or some other obnxious colors on their faces (but overall I think they did a great job with full screen full of action movies considering the technical limitations). I also remember a Digital Arts game with a similar problem. I would rather see some background object be the wrong color than people, but I understand its hard to tell that to an algorithm.

Attachment 3737Attachment 3738Attachment 3739Attachment 3740

[kool kitty89]

I don't have the Indeo 3 version of the intro movie.

If you care, I could email you a copy of it. (it's only 17.6 MB after all)
It's interesting to note that the Indeo 3 version lacks the jaggies (especially visible on black outlines) seen in Indeo 4, but is also much blurrier looking in general on top of heavier posterization and detail loss. (the blur is part of that detail loss)

There are definitely better sources to work from though, at least if one had a way to rip the Sonic Jam or (better) Gems videos. Actually, at the 256x112 frame size and the typical Sega CD cinepak compression ratio (allowing 256x224 10 fps or 256x152 15 FPS), 20 FPS should be reasonably possible, so the PC versions would be too slow for that.

Looking at the Sega CD good ending and the PC good ending, there is obvious color and brightness change. The Sega CD one is much more colorful and in my opinion the colors on the Sega CD are much better. When I started to convert the PC version to the VDP palette, the ugly colors looked bad

Yes, there's a general change to the color for the MD version, though the Indeo compression makes it much worse. (the original animation itself has more subdued colors with finer shading gradients)

But still, the source video is definitely a bit more colorful than the Indeo Versions show, not to mention higher framerate/resolution/detail/etc:
http://www.youtube.com/watch?v=FKMC1x5pU0o

(on another note, there's something really odd going on at ~10 seconds . . . Sonic's shadow on the mountains is really huge -something I hadn't noticed before, but my brother pointed out recently )


If one were to attempt to more accurately convert the source animation to the MD format, you'd definitely want to start with a high quality source, especially for the ending sequence. (the ending compressed particularly badly with Indeo while it seems to have fared better than the intro for the MCD rendition) It's rather odd that the endings weren't re-encoded in Indeo 4 along with the intro.
And on the note of downconverting to lower color in general, Tomaitheous mentioned 1 method that involved posterizing to 12-bit and then checkerboard dithering to 9-bit paletted. (albeit that wouldn't work well for video with heavier detail/shading -it would get really posterized and could be preferable to accept heavier dithering- but for most animated style stuff, that might be a preferred method to use)

I personally still prefer the Indeo renditions over the MCD (even on a static frame basis) at least for the intro. (the Intro also has a whole lot hacked out and altered on the MCD version -a bunch of missing scenes and for some reason the sequence panning across the chain from the planet plays in reverse of what's in the original animation). The ending sequence compares much more competitively though. (especially once the text starts scrolling)

Edit:
The ending sequences actually cater much more to the MCD format due to the slower pacing (and lower actual framerate at times) of the source animation:
http://www.youtube.com/watch?v=iu4JKfGOQyo


http://www.youtube.com/watch?v=WbyWwy0YOmU


edit:
Odd, the Gems Collection version above is listed as playing at 1/2 speed, but this video looks about the same (though the music is synced differently)
http://www.youtube.com/watch?v=kl9NLRBMrYQ


Apparently the source animation plays much faster than any of the videos used in releases of the game:
http://www.youtube.com/watch?v=BZB6uMCkVL0


Actually, looking closer, it seems that (after the screen drops to the small size), the MCD animation matches the faster source animation rate fairly closely (though with pauses between clips) and is definitely playing faster than the Gems example (not sure about PC).
The 256x112 portion of the MCD ending is slower though (much like the Gems animation).



However, as far as the redrawn/pixel-art style conversion method goes, Sonic CD definitely looks nicer than some other examples (non CD version of Dragon's Lair on PC/ST/Amiga, in-game portions of Time Gal, etc). In Time Gal's case it's especially odd since the attract/intro sequence doesn't use that redrawing method but more of a direct conversion with dithering (seems like a similar conversion method as Tenbu MCD Special), but the in-game parts are all posterized/low color and (often) with odd-looking outlines on things (especially when black outlines are used -something that screws up the look of some pixel art/sprite/BG animation in normal 2D games as well IMO). The Time Gal intro is certainly grainy looking, but I much prefer it to the in-game style at least. (much more so if the framerate was better -even uncompressed, it doesn't make sense to be ~6.3 FPS for a 192x160 window)


I'm not positive, but it seems like the MCD version may increase the FMV framerate when the window shrinks and credits appear. (which would make sense if only the video is streaming and the credits are an independent scrolling text layer) That's definitely something the PC version doesn't do. (and you can see visible artifacts on the text, especially interframe artifacts)

(so the conversion from this source seems pointless to me since it has less audio quality, worse colors despite having more, and just a better frame rate). Attached are two similar frames from each version.

The audio is actually higher quality (22 kHz 16-bit stereo) though at a lower sample rate. In any case, you'd probably be better off using the 44 kHz red-book version as the source if you wanted to replace the audio.

Also, the attachments you posted don't seem to be working.

In terms of bad FMV, parts of the Power Rangers were bad since they were converting existing footage to the Sega VDP and I remember a point where the people had green or some other obnxious colors on their faces (but overall I think they did a great job with full screen full of action movies considering the technical limitations). I also remember a Digital Arts game with a similar problem. I would rather see some background object be the wrong color than people, but I understand its hard to tell that to an algorithm.

I wonder if some algorithms actually managed to address that somewhat. It seems like some examples do show considerably more errors in the further BG than foreground/people, but maybe that's just up to chance and/or manual retouching. (Wirehead comes to mind, especially the scenes looking through the front door from inside the house -the sky and trees look really off at times, including pink/magenta sky, but the people continue to look decent for the most part)

[bgvanbur]

For time gal, (75*0x800-32552)/(20*24*32) would mean you could get a max of 7.8 fps just for the uncompressed tile data and 32KHz audio data. But if you start adding in palettes and palette maps, this optimal frame rate gets smaller, so ~6.3 seems appropriate.

For Sonic CD FMV audio, I think the original FMV 32KHz 8 bit mono would suffice since 8 bit mono is the easiest to use for SCD FMV.