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In the early 1990s, the new buzzword for PCs was "Multimedia", and the gold standard for multimedia performance usually talked about was "full-screen full-motion" video playback. Many will remember early digital videos being played in tiny windows on Windows PCs. In contrast, the often-plugged aspiration was to have basically long-playing digital video on the PC at roughly the quality of a VCR / Standard-Definition Television, utilizing the full screen area, around 30 fps, and including realistic sound.

I believe that such capability became commonplace on new PC hardware around the middle of the 1990s. I remember CD-ROM games such as "The 7th Guest" becoming popular based on these sorts of abilities, though that particular game falls short of the quality mark described above.

Naturally, this whole endeavor revolves around hardware bandwidth and codec's, which includes software components. My question is, can it be pin-pointed the specific hardware/software technologies and when they went mainstream on new PC's to support this level of multimedia video?

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    Would Wing Commander 3 qualify? Or Wing Commander 4? (There was a DVD version of the latter too, using a hardware decoder...) – Stephen Kitt May 15 '18 at 14:44
  • Are you interested specifically in IBM PC compatibles, or in personal computers in general? For example, would something allowing the Apple Macintosh to do the same qualify as an answer? – a CVn May 15 '18 at 14:57
  • @MichaelKjörling I limited it to PCs to avoid making the question overly broad. – Brian H May 16 '18 at 2:55
  • @StephenKitt I think WC3/WC4 level of video playback should qualify. WC3 is obviously lower quality, but I think delivers on the sort of Multimedia PC "experience" that the PC press was hyping at the time. – Brian H May 16 '18 at 3:18
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  1. An efficient motion video codec (such as MPEG-1, 1993) to make storage or transmission of digital video practical.
  2. Real-time motion video decoder chips such as the C-Cube CL4000 (1993), because efficient codecs are processor-intensive. Or a sufficiently fast CPU such as the Intel Pentium (1993) and a high resolution multimedia timer (I think the necessary circuitry was first incorporated in sound cards before moving to motherboard chipsets).
  3. A high speed path between the video decoder chip and the video memory or video output. On PCs, this is achieved either by placing the chip on the video card (such as the ATI Rage 3D, 1996), or as described by @tofro by connecting through a VGA card's high speed feature connector to access video memory directly (such as the Sigma Designs Reelmagic CD lite, 1993), or by switching from ISA to VLB (1992) or PCI (1993).
  4. 15-bit color or better (late-'80s), to avoid palette issues.
  5. A redistributable high capacity storage medium (such as compact discs, 1982) or a high speed network (such as satellite Internet, mid-'90s) to get the video data into the PC.
  6. Buffered PCM audio such as a Creative Labs SoundBlaster sound card (1989).

To make fullscreen full motion video mainstream, the following technologies were needed:

  1. A software abstraction layer for video decoding such as DirectShow (1998).
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    Re. (3): or, as referenced by tofro, the feature connector of SVGA cards, which is a digital data bus directly to video memory that bypasses every other component in the computer. – Tommy May 15 '18 at 18:54
  • @Tommy That's interesting, I've never used or even noticed the feature connector before. – snips-n-snails May 15 '18 at 19:22
  • Were MPEG-1 decoder chips a "mainstream" feature present on most PCs beyond some date? I thought software codec's were dominant. – Brian H May 16 '18 at 15:55
  • @BrianH Software codecs were the least common denominator but struggled to achieve full screen video until at least the Pentium (I've updated point #2 above). Video cards and maybe also sound cards incorporated hardware video decoding but required proprietary software (usually bundled with the card) until around Windows 98 (I've added point #7 above). I think you're right that MPEG-1 decoder chips became a mainstream feature on PC chipsets at some point but I'm not sure when. – snips-n-snails May 16 '18 at 18:09
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I'm going to stick my neck out and argue, chronologically:

  1. QuickTime;
  2. Cinepak;
  3. MPEG1.

QuickTime, which launched in 1991 and therefore predates Video for Windows by about a year, introduced a fairly general framework for containers and codecs, and an initial video codec which was a fairly simple thing. No motion compensation, just altering or not altering different 16-pixel parts of the display in each frame, with differing precisions (ranging between a single colour for all 16 to a different colour for each pixel).

Cinepak, from 1992, was the first codec added to both QuickTime and Video for Windows that promised 'full-screen' (i.e. 320x240), 'full-motion' (15fps) video. It's actually broadly similar to QuickTime in just dividing the display into macroblocks and assigning each a particular fill, then modifying those fills frame-by-frame, but there's an extra level of indirection as to block contents, a fixed-size codebook and codebooks receive only sequential updates from one frame to the next, key frames aside.

Cinepak is the codec you're used to from the Saturn, Mega CD, 3DO, etc — everything that produced full-motion video in software.

MPEG-1 was also standardised in 1992 and introduces a substantial number of new ideas:

  • use of the frequency domain to describe macroblocks in terms of their significant frequency content (via DCT in this case);
  • sampling luminance at a greater frequency than chrominance;
  • motion estimation of macroblocks from frame to frame — macroblocks can now be updated from frame to frame not only by content but by position;
  • bidirectional frames, which describe a frame not just as a mutation from the prior, but as a combination of mutations from the prior and the next.

That adds up to a substantial extra processing burden, and an extra buffering burden for bidirectional frames but it gets you "VHS quality video" (i.e. 320x240, 30fps) at CD-ROM read speeds, where Cinepak could do only half the frame rate at the same data rate.

A desktop PC could be equipped with something like a ReelMagic card for MPEG-1 playback; consoles like the Philips CDI, Saturn and 3DO tended to have a slot where one could add an after-the-fact MPEG decoder, primarily for playing Video CDs.

A Pentium can decode MPEG-1 in software; a 486-class machine can do something between Cinepak and MPEG-1.

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    I saw an Amiga 2000 with a GVP SCSI card playing full screen full motion proprietary video at World of Commodore in 1990; I remember they were demoing it as a way of showing how fast their SCSI controllers were... I've never seen anything else related to that demo, but I know it was full screen, full motion, on an Amiga in 1990. – Geo... May 15 '18 at 17:24
  • @Geo... I'll bet it was uncompressed (depending on your feelings about HAM and whether it was using it); great for a bandwidth demo, making exactly the point you need to make, but impossible to ship! – Tommy May 15 '18 at 18:51
  • I've had a quick check of my guesses, and a 320x200 frame at 6bpp (i.e. HAM6) costs a bit less than 48kb. Do that at 30fps and you're still talking about bandwidth of only around 1.4mb/sec. The 1986 SCSI standard technically runs up to 5mb/sec but real life applies so you can bet a sustained 1.4mb/sec, including seeks and actually getting the data from the SCSI source into memory in a functioning system, would still be a noteworthy thing in 1990. – Tommy May 15 '18 at 19:07
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    Just playing an MP3 audio file took up the majority of my 486DX2/66 CPU's time. I don't think it was capable of playing any videos. Then again I never tried... – Michael Hampton May 16 '18 at 5:12
  • I had small videos that would play on my 486 DX/50, but IIRC none of them had sound – Brian Knoblauch May 16 '18 at 16:08
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The first real "Multimedia" experience I had was with a Sigma Designs REALMagic MPEG decoder card that was one of the first that could full MPEG decoding in hardware. It had to be connected to the feature connector of your (S)VGA card to transport the picture to the screen. The PC itself didn't have to do much with these cards except maintaining a relatively constant data feed of 2 MBit/s into the card. The first cards of that type showed up in the mid-nineties and replaced rather low-quality software decoding of videos (AVI, Quick Time, Video for Windows)

PCs were far from being capable of doing real-time MPEG-2 decoding in software back then. They had to be supported with a bit of a hardware lift to play proper video.

  • Before the REALMagic cards, we had PCMotion and an overlay card by (I think) Matrox - the PCMotion played the mpeg out as video which was then used as an input to the Matrox, where it was chroma keyed on screen over a big magenta rectangle. Just a few years later, ActiveMovie was doing software only playback of MPEG1... – Geo... May 15 '18 at 17:08
  • Ahh, the infamous EM8300 and the Creative Encore DXR3+ set. – Janka May 15 '18 at 21:35

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