Video Potpourri II

Sometimes, one needs to discuss related subjects that do not by themselves warrant a full blog entry.  Hence the video potpourri series, in which I can talk about aspects of display technology.

I.  Composite Artifact Color Emulation

Composite artifact color emulation has been around for a long time.  Unfortunately, in many cases it just isn't very good at trying to replicate the look of a composite monitor.  Simple schemes just assign a color arbitrarily to a group of two or four monochrome pixels.  Mainline SVN DOSBox tries to simulate CGA composite color as if it were a VGA mode.  The colors are reasonably accurate to the real IBM CGA cards, but the text color fringing is rather blocky.  There are custom builds that use filtering and 16-bit color to give a more subtle impression of the composite color, but it still looks much, much cleaner than the real image.  You can obtain a custom build with better composite color emulation here : http://www.vogons.org/viewtopic.php?f=41&t=12319&start=660#p501453

Restoring the Fluid Look to Analog Video

As we all know theatrical sound film releases are typically projected at 24 or 25 frames per second.  Film is a progressive medium where each film frame captures an image at a discrete point in time.  However, film must be developed before it can be exhibited and must handled by experienced technicians, making it a costly medium in which to produce artistic works.  To reduce flicker, a shutter in the camera would open or close twice for each frame.

Prior to the advent of television, celluloid film was the only commercial means to display visual moving images.  However, the introduction of wholly-electronic television broadcast and receiver systems meant a massive change.  TV broadcast cameras were able to achieve acceptable image quality by broadcasting images in an interlaced format.  A broadcast camera and a TV tube display images in a set number of lines, and the electron scanning beam inside the tube scans or displays each line sequentially, then returns and draws the next line.  (Think of a typewriter.)  When it gets to the bottom of the tube, it returns to the top of the tube and draws the next set of lines.

In order to allow the electron beam sufficient time to draw all the lines, interlacing was used.  In an interlaced format, "frames" become "fields". A field only captures the odd or the even lines of the TV camera lens.  After all the odd lines in the first field are captured, then all the even lines of the second field are captured.  In the NTSC countries, 59.94 color fields (formerly 60 fields for B&W NTSC) are captured each second.  In PAL and SECAM countries, 50 fields are captured each second.  When this is broadcast to a TV screen, the fields are displayed as they are captured.  The high number of displayed fields avoids flicker on the TV screen.

Nintendo Mini Mania Redux - The Classic Mini Family Computer

Nintendo has released another retro-themed surprise.  Back in July, Nintendo announced the NES Classic Edition/NES Mini, an emulation box containing 30 classic NES games.  Here is the original trailer for it :  https://www.youtube.com/watch?v=qAGVilt3Rls  I discussed it here :

http://nerdlypleasures.blogspot.com/2016/07/nes-classic-editionnes-mini-nintendos.html

Yesterday, Nintendo announced a Famicom version for the Japanese market.  Like the NES Mini, the "Classic Mini Family Computer" is a miniature replica of a Famicom with a power and a reset button.  It also has 30 games and will cost 5,980 Yen, which is close to the NES Mini's $59.99 price.  It is going to be released on the same day as the NES Mini, November 11, 2016.  While the official trailer is in Japanese, the visuals are self-explanatory :

Older Sci-Fi Shows in the HD Era

So, you want some of your classic sci-fi shows on Blu-ray?  How do they do that you may ask?  Well, in many cases it depends on when and where the show was created.

In the 1950s through the mid 1980s, U.S. science fiction TV was shot entirely on film.  Classic shows like The Twilight Zone, The Outer Limits, Star Trek, Night Gallery, Kolchak: the Night Stalker, The Six Million Dollar Man, Wonder Woman, Battlestar Galactica, The Incredible Hulk, Buck Rogers and V: The Series all had the Hollywood look.  Effects were done on film, practical where necessary, optical as required.

Then in 1986, Star Trek: The Next Generation started its seven year run.  This series initiated a revolution in special effects.  While live action was still caught on film, wholly special effects scenes depicting the Enterprise and the various ships and worlds it encounters would often be generated on video with the use of computer graphics imagery (CGI).  CGI would often make its way into the live action as well.  Unfortunately, these images would be constructed in standard definition.  This method of production continued for almost two decades, every Star Trek series (except the last season of Enterprise), Babylon 5, Farscape, Firefly, The X-Files, Hercules and Xena used this method.

Accessible Good Famicom Games

The Famicom had over 1,000 games released for it during its lifetime.  Hundreds of those games were never released outside of Japan, and there were only a few releases of Japanese games exclusively in Europe.  Of course, many, many of those games that never officially made it out of Japan are terrible, as were many games that did make it overseas.  In this post I am going to list many good Famicom cartridge games that were not released for the North American NES console.  Not all the games identified below are classics, but all have their virtues.  Famicom Disk System games have already been mostly covered elsewhere :

http://nerdlypleasures.blogspot.com/2016/04/worth-loading-times-famicom-disk-system.html

The first list is of games that are English-friendly.  These games do not use a lot of Japanese text and what text there is is not essential to completing the game.  Most of these games have translation patches as well.  Many tend to be simpler games, namely shooters and platformers :

Two Late Classic Apple II to PC Ports, Unalike in Dignity

Even though the Apple II was very long in its lifespan by the end of the 1980s, there was a fair bit of software still being released for it.  The Apple II was very strong in the educational market, computer labs across the United States had yet to upgrade to the PC platform.  The Apple II had many, many classic games.  Most of them were ported to the PC at some point, but by the end of the 1980s the number of A2-to-PC ports (that did not have the name Carmen Sandiego in the title) was dwindling.

Even so, two classics of the Apple II did make their way to the PC platform in the late 1980s and they are the subject of this blog entry.  The first is MECC's 1985 update of The Oregon Trail.  The second is Jordan Mechner's Prince of Persia, programmed on and released for the Apple IIe, IIc and IIgs in 1989.  MECC ported the Apple II version of The Oregon Trail to the IBM PC in 1988.  Mechner and Broderbund ported the Apple II version of Prince of Persia to the PC compatibles in 1990.

The Oregon Trail is the simpler game, in fact it was an update of an earlier version MECC made for the Apple II in 1980.  That version was mostly text-based and occasionally displayed simple wire-frame graphics and a little music.  Before personal computing, Oregon Trail was played on mainframes on a time-share basis.  But the 1985 Apple II version is undoubtedly the most popular version of the game.  The 1985 version requires 64KB of RAM on an Apple II.  This version was ported to the PC by MECC in 1988.  The PC port requires 512KB of RAM and at least a CGA card.

Prince of Persia is a spiritual successor to Mechner's Karateka, another big hit.  Both were published by Broderbund.  Prince of Persia takes the rotoscoped graphics and one on one combat of Karateka and combines them with running and jumping mechanics, obstacles, traps and triggers.  It requires 128KB of RAM and an Apple IIe capable of displaying double high resolution graphics, a IIc or a IIgs.  It only uses double high res graphics on the title screen and story text screens (four screens).  Mechner supervised the ports of the game to the IBM PC compatibles and the Amiga in 1990.  It supports CGA, Hercules, Tandy, EGA and VGA and a variety of sound cards and 512KB-640KB depending on the graphics mode.

When it came to porting these games to the PC, MECC did an outstanding job.  Broderbund and Mechner, not so much.

Recording the IBM PC Speaker's Sound

The PC Speaker was the first audio device that PCs used.  In some form or another, it is contained in almost every PC ever made.  In the original IBM PC, the Model 5150 released in 1981, the speaker was a distinct cone 2.25" in diameter.  And it was loud, but it had to be in order to compete with the noisy power supply fan and the seeking of the disk drives!  The tones it output were pure, and while they were rather harsh they were also clear.

However, eventually the PC Speaker began to shrink in size and eventually give way to the tiny piezoelectric tweeters that are just too quiet to do justice to any kind of complicated audio.  (You can blame IBM for putting the idea into other manufacturer's heads because the IBM PCjr., released in 1983, used a piezo tweeter for the PC Speaker.)

When emulators like DOSBox became mature, they could easily output basic PC Speaker audio.  Basic PC Speaker audio is essentially a square wave with a fixed volume level and a 16-but frequency selector.  They can have difficulty with the more complex sounds produced by Pulse Width Modulation, which essentially sends changes to the frequency of the square wave to the speaker faster than the speaker cone's driving circuitry was intended to handle.  This requires a much more rigorous emulation of the CPU, the timer and the "analog" characteristics of the audio generation.

Famciom vs. AV Famicom External - Internal Audio Mixing

There is a myth that the AV Famicom is too quiet when it mixes internal audio with external audio.  The myth goes that the external cartridge audio drowns out the internal audio from the console and gives an unbalanced and unfair impression of what the programmer intended the music and sound effects to sound like.  The conclusion is that an original Famicom, preferably an earlier model, is the ideal way to experience Famicom audio.  However, this conclusion is too simplistic and the internal/external mix is not as extreme on standard Nintendo Famicoms and AV Famicoms as one may be led to believe.

Of course Famicom audio has its own problems.  The first problem is that genuine Famicom audio is encoded into RF and decoded in a TV.  The baseline audio has a buzz and the output of the audio sounds like it was run through an oppressive low-pass filter.  The second problem is that playing a Famicom with its RF video and hardwired controllers is something of a chore.

I have made some recordings of several games which use Famicom expansion audio and internal Famicom audio.  The games in question are :

Zelda no Densetsu (Famicom Disk System, The Legend of Zelda)
Akumajou Densetsu (Konami VRC6, Castlevania III: Dracula's Curse)