Search found 248 matches

by Bisqwit
Wed Jan 04, 2017 2:54 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

Bisqwit, can you run your filter against this ROM: http://forums.nesdev.com/viewtopic.php?f=2&t=15080 Thusly complied . I just noticed that when I talked in the other thread (linked above) about the QuickBASIC NTSC codec, which is faster in performance than my previous C++ NTSC codec, I had totally...
by Bisqwit
Fri Dec 30, 2016 1:59 pm
Forum: NESdev
Topic: NTSC pattern torture test ROM
Replies: 27
Views: 20636

Re: NTSC pattern torture test ROM

My captured picture is actually an interlaced image. I was wondering why the per-scanline color alterations appear to be twice as thin/frequent as in my screenshots. Thanks for explaining. EDIT: Hmm, I wonder if you can generate composite video in real time with e.g. Raspberry Pi GPIO DAC (or some ...
by Bisqwit
Thu Dec 29, 2016 1:20 pm
Forum: NESdev
Topic: NTSC pattern torture test ROM
Replies: 27
Views: 20636

Re: NTSC pattern torture test ROM

I'd be really grateful if someone modifies the constants to the PAL standard. It is not only the matter of modifying the constant. You have to reverse the phase of the colorburst for every other scanline, too (or something like that, I don't remember the specifics). The QuickBASIC code has a newer ...
by Bisqwit
Thu Dec 29, 2016 2:58 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

feos wrote:Bisqwit, can you run your filter against this ROM:
viewtopic.php?f=2&t=15080
Thusly complied.
by Bisqwit
Thu Dec 29, 2016 1:25 am
Forum: NESdev
Topic: NTSC pattern torture test ROM
Replies: 27
Views: 20636

Re: NTSC pattern torture test ROM

Here are some sample pictures of what my QuickBASIC NES emulator produces for this test ROM: http://bisqwit.iki.fi/kala/snap/qbnes-ntsctorture1.png http://bisqwit.iki.fi/kala/snap/qbnes-ntsctorture2.png http://bisqwit.iki.fi/kala/snap/qbnes-ntsctorture3.png The horizontal lines in the bottom left of...
by Bisqwit
Tue Jun 21, 2016 3:47 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

HardWareMan wrote:So, I build CVBS within PPU rules and feed it to TV tuner. Where I can swap R and B?
I did see your post earlier, but I don't know what a CVBS is. So I made the assumption that your post is related to the topic.
by Bisqwit
Tue Jun 21, 2016 3:38 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

Make sure your blue and red are not swapped (RGB v.s. BGR). How can it possible? It's just a 12 square waveforms with linear phase shift. I presume you are doing NTSC signal to RGB conversions. The code I pasted generates 32-bit integers where certain eight bits represent blue, certain eight bits r...
by Bisqwit
Tue Jun 21, 2016 3:06 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

Make sure your blue and red are not swapped (RGB v.s. BGR).
by Bisqwit
Sun Jun 05, 2016 8:24 pm
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

I said earlier the brightness & hue options have not been particularly finetuned. I have updated the code in the first post now. I generated a palette with Drag's tool at http://drag.wootest.net/misc/palgen.html , set brightness to -0.15 (the default was -0.20), all clipping methods to desaturate, a...
by Bisqwit
Thu Jun 02, 2016 12:59 pm
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

The blue is kind of different though. Can you say a few words how your filter only adds moire to color borders? I can't instantly see it form the code. It comes naturally from how NTSC works. To accurate determine a both color and amplitude, you need 12 samples of the color signal (in terms of NES P...
by Bisqwit
Thu Jun 02, 2016 10:43 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

It all makes sense now, thank you. Can you feed it this ROM? Preferably, in both monochrome and color. http://bisqwit.iki.fi/kala/snap/ntsc0_pale0_thu.jpg http://bisqwit.iki.fi/kala/snap/ntsc0_pale1_thu.jpg It seems to be a bit on the unsaturated side, but like I said before, I haven't particularly...
by Bisqwit
Thu Jun 02, 2016 10:07 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

As I just explained. Maybe you didn't read it. In my QuickBASIC NES emulator , that does contain a NTSC modem, I save the generated NTSC signal into a file.* Then this file gets read by the C++ program showcased in this thread. The C++ program generates RGB. The main program nearest-neighbor-scales ...
by Bisqwit
Thu Jun 02, 2016 9:43 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

Right. Can you post some example images of your filter? Well I haven't put it into any emulator, but here's three snapshots created by recording the NTSC signal from my QuickBASIC NES emulator, saving it into file, and decoding with this C++ program, rendering at 640x240 (with no interpolation), wr...
by Bisqwit
Thu Jun 02, 2016 8:14 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

Woah how smart! That still can be done in old C++ with #define, can it? I think lambda is also traslatable. If I manage to tweak it to meet the PAL standard, it will save me months of brainstorming. Yes, lambda can be converted into a #define and constexpr into const, to support compilation on more...
by Bisqwit
Wed Jun 01, 2016 11:54 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 21565

Re: New NTSC decoder with integer-only math (short C++ code)

tepples wrote:Under what license may this decoder be used?
MIT. Or CC-BY-SA, I guess. Since this is more of a documentation thing.