nesdev.org

I created a NES emulator. Target: YouTube. Umm, what? My goal was to produce an emulator that has as compact source code as possible, so that it -- the source code -- can be showcased within a 15 minutes of a YouTube video that is not too much sped up that it cannot be read without pausing. Regular ...

The image does not shift. The amount of time between hsync and pixel N is always the same -- exactly (N/1.5/3.579545MHz). A purely black-and-white image will not shake like that. Only the angle of the reference color (yellow) is what shifts from scanline to scanline. You are right. Somehow the fact...

So, we usually have 3 layers for a 1:1 image - a red, a green and a blue layer. The idea seems to be sliding the green and blue plans to the right by 2 or more pixels...? What happens, for example, in the left side of the image? Not by pixels. By half-clocks. I will explain this a bit. Imagine that...

Just a heads-up, I fixed a bug in the NTSC rendering. The subpixel version (in the first post) looks nicer now...

The red "PRESS START TO PLAY." text seems a bit chunkier in the subpixel version Subpixel rendering won't really help with monochromal details (purely or mostly red, green or blue） because they are confined to one subpixel channel to begin with. > Also, the white text at the bottom seems ...

On RGB displays, subpixel rendering can be an interesting topic. Here is a small sample picture, made small for your convenience (still 111 kilobytes). http://bisqwit.iki.fi/kala/snap/subpixelscrollsample.gif No, don't zoom it, for it must be viewed at 1:1 pixel correspondance to the original image....

TAS is based entirely on the concept of making the system run slower so the player has all the time they want to decide on the next move rather than being limited by their reflexes. The ratio of the player's avatar's speed to the game environment's speed remains constant, in either case. Once you w...

I'm kind of rusty about how to do that heh, me too :). Perhaps it would work like this. mog@chii:~$ maxima Maxima 5.24.0 http://maxima.sourceforge.net using Lisp GNU Common Lisp (GCL) GCL 2.6.7 (a.k.a. GCL) Distributed under the GNU Public License. See the file COPYING. Dedicated to the memory of W...

As for the NTSC RGB matrix... (And do the matrix multiplication.) I've modified the php test code that you've posted to the wiki. Haven't tested it, but it should get the job done. Note that I've set saturation to 1.0 and gamma to 2.2. Thanks. That's not what I asked though; I was asking someone to...

Slightly more accurate chroma filtering: 24 subpixel boxcar for I 48 subpixel boxcar for Q Yeah, I see you edited your post: Using sizes that are not multiples of 12 produce prominent chroma dots. But the sizes 24 and 48 produce, as expected, more prominent chroma leaking artifacts than 12 (edges o...

I added some documentation and algorithms at http://wiki.nesdev.com/w/index.php/NTSC_video.
Editors, feel free to touch if you feel that it's too original-researchy.

The funny fact is that my TV does something like this a bit. I also remember seeing the chroma dots (the dot pattern appearing on solid-color surfaces) on a PAL color television on occassions, but I really cannot remember when, in which kind of circumstances. Whether they appeared when the channel ...

Just a little question: the NES output come from the RF or composite cable for those pics? Is not the difference only in whether it is modulated by the aerial carrier frequency (i.e. RF modulation) and whether the audio is also transmitted along it? I'm not doing audio side-effects in this simulati...

I implemented the 1.4 Mhz and 500 kHz lowpass filters to I and Q respectively. Y is filtered at 3.5 MHz. (Actual implementation weighted-averages them at 31, 86 and 12 samples respectively; it's not a perfect solution to lowpass-filtering...) It also does the 57 and 147 degree offsets to the colorbu...

No one looked at my pictures from the oscilloscope? Let me tell you a terrible secret: PPU makes color subcarrier only for dyed colors. I do not understand how that is a secret. That is even described at http://wiki.nesdev.com/w/index.php/NTSC_video . I did look at the pictures. For comparison, her...