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CRI's Video and Sound Software Development Tools

Sega's subsidiary partner CSK has released a couple of development tools for the Dreamcast, where one tool is for video and the other is for sound:

CRI's MPEG Sofdec (MPEG1 Software Decoder)

  • MPEG1, digital format
  • full screen, in 24-bit color
  • 24 fps or 30 fps
  • 320 × 240 resolution
  • stereo 16-bit 44.1 KHz sound
  • compression as high as 1/50
  • 50 percent CPU utilization
  • 2 Mbps or 4 Mbps of GD-ROM access bandwidth needed out of a total of 14,745 Mbps (1800 KBytes/s)
  • 2 hours of playing time on a single Dreamcast GD-ROM
  • used in VF3tb, Pen Pen Triicelon, July, Godzilla Generations, Aero Dancing, Buggy Heat, and Sonic Adventure
A couple pictures showing the MPEG1 Software Decoder at work, with a tea pot being rendered in real-time, while environment mapping the video onto it's surface! This shows that while doing the MPEG1 Software Decoder, there is lots of processing left for detailed 3D objects.
CRI's ADX Sound Compression Technology
  • supports up to six 16-bit 44.1 KHz CD quality digital sound channels
  • also supports 22.05 KHz (TV/FM quality), and 11.025 KHz (AM quality)
  • 1 percent CPU utilization
  • used in Aero Dancing, Buggy Heat, Evolution, Power Stone and Sonic Adventure
Quality vs Playing Time
Frequency
Channels
Bandwidth
[kBytes/s]
Playing Time
[Hours]
Quality
44.1 KHz
stereo
49.6
5.5
CD
mono
24.8
11
22.05 KHz
stereo
24.8
11
TV/FM
mono
12.4
22
11.025 KHz
mono
6.2
44
AM

Here is the Japanese CRI MPEG Sofdec press release and CRI ADX press release at CSK's website. You can possibly expect MPEG2 (DVD quality) software decoders in the future, even though video quality so far on the Dreamcast looks excellent!
(Source: phu, Gamers' Republic article)