Optimal timings

The advanced timing options on the OSSC allow for fine control over how the output image is generated and how the analogue signal is sampled. In some cases it is possible to adjust these values to perfectly match the incoming analogue signal from a console. This results in a very sharp image (possibly even too sharp for many people's tastes).

The table below contains some preliminary timings for popular consoles, it should be considered a work in progress, do not be surprised if further fine tuning is required. You will almost always be required to fine tune the sampling phase after making these adjustments.

Console / mode	Dots per scanline / no. scanlines / @dotclk	OSSC base mode	Modified parameters	Notes	PC modeline
NES 256x240 @60.10Hz	341* / 262 / @5.37MHz(NTSC) [1][2][3]	256x240		To reduce jitter in couple topmost lines, try disabling ""Allow TVP HPLL2x" and/or using mask. * one scanline is typically 1 dot shorter on every other frame	Modeline "ossc_nes_1280x720_60.08" 80.55 1280 1385 1510 1705 720 729 738 786 -hsync -vsync
SNES 256x240/224 @60.10Hz	341* / 262 / @5.37MHz(NTSC) @5.32MHz(PAL) [4]	256x240		* one scanline is typically 1 dot shorter on every other frame	Modeline "ossc_snes_1280x720_60.08" 80.55 1280 1385 1510 1705 720 729 738 786 -hsync -vsync
Mega Drive 320x224 @59.92Hz	320×8 + 86×10 (?) / 262 / @53.693175MHz(NTSC) @53.203425MHz(PAL)	320x240	H.samplerate=427.50	Video tutorial
Mega Drive 256x224 @59.92Hz	342 / 262 / @5.37MHz(NTSC) @5.32MHz(PAL) [5][6]	256x240	H.samplerate=342	Video tutorial
N64 320x237 @59.82Hz	773.5 / 263 / @12.17MHz(NTSC) @12.41MHz(PAL) [7][8]	320x240	H.samplerate=386.75, H.synclen=22, H.backporch=36	Every other visible dot (of 640) is interpolated
PlayStation 320x224 @59.82Hz	426.625 / 263 / @6.71MHz(NTSC) @6.65MHz(PAL) [9] [10]	320x240	H.samplerate=426.60	Example games: Chrono Cross, Final Fantasy VII & VIII, Klonoa
PlayStation 384x224 @59.82Hz	487.571 / 263 / @7.67MHz(NTSC)	384x240	H.samplerate=487.55, H.synclen=63, H.backporch=18	Example games: Ape Escape, Grandia, Oddworld, Tomb Raider 1 & 2
PlayStation 256x224 @59.82Hz	341.30 / 263 / @5.369MHz(NTSC)	256x240	H.samplerate=341.30	Example games: Adventure of Little Ralph, Castlevania SotN (in-game only), Tactics Ogre
PlayStation 512x224 @59.82Hz	682.6 / 263 / @10.74MHz(NTSC)	512x240	H.samplerate=682.60	Example games: Crash Bandicoot, Soul Reaver, Spyro, Tekken
PS2 512x400i @59.94Hz	686.4 / 525 / @10.8MHz(NTSC)	480i / 576i	H.active=512, H.samplerate=686.40, H.synclen=44, H.backporch=84	Example games: Megaman X7, Castlevania Lament of Innocence
PS2 640x400i @59.94Hz	858 / 525 / @6.71MHz(NTSC) @6.65MHz(PAL)	480i / 576i	H.active=640, H.synclen=44, H.backporch=116	Example games: GTA III, Crash Bandicoot Wrath of Cortex
PS2 256x240 @59.94Hz	858 / 263 / @6.30MHz	256x240	H.samplerate=858	Example games: FCEU, SNESticle and some emulators
Saturn 320x240 @60Hz	427 / 263 / @6.72MHz(NTSC) [11][12]	320x240	Video LPF = 9MHz, H.samplerate=427	Example game: World Heroes Perfect (has in-game letterboxing)
Saturn 352×224 @60Hz	455 / 263 / @7.16MHz(NTSC)	320x240	Video LPF = 9MHz, H.samplerate=455, H. active = 352	Example game: All of the various Capcom arcade fighting game ports
Saturn 704x480i @60Hz	910 / 263 / @14.32MHz(NTSC)	480i	Video LPF = 9MHz, H.samplerate=910, H. synclen = 62, H. backporch = 98, H. active = 704	Example game: Virtua Fighter 2 (stage areas)
Neo-Geo MVS 320x240 @59.19Hz	384 / 264 / @6.00MHz [13]	320x240	H.samplerate=384, H.backporch=25
DC VGA 720x480 @60Hz	858 / 525 / @27MHz [14]	480p	H active=720	Outputs games at 640x480 in a frame of 720x480.
GameCube 480i @59.94Hz	858 / 525 / @13.5MHz	480i	H.active=720
GameCube 480p @59.94Hz	858 / 525 / @27MHz	480p	H.active=720	Only available on GameCube models with a Digital AV Out port. Requires proprietary RCA component or D-terminal cables, or a third-party adapter. Supported by many NTSC games, but no PAL games.
Wii 480i @59.94Hz	858 / 525 / @13.5MHz	480i	H.samplerate=858 for both 4:3 and 16:9 modes, H.active=640 and 720 in 4:3 mode and 854 in 16:9 mode
Wii 480p @59.94Hz	858 / 525 / @27MHz	480p	H.samplerate=858 for both 4:3 and 16:9 modes, H.active=640 and 720 in 4:3 mode and 854 in 16:9 mode	Requires RCA component or D-terminal cables. Supported by most, but not all games.
Wii 320x240 @59.82Hz	429.05 / 263 / @6.75MHz	320x240	H.samplerate=429.05	Example Games: Many Virtual Console games (only if output resolution is set to in 480i in System Settings)
GBI ULL 480p @59.72Hz	866 / 522 / @27MHz ?	480p	H samplerate=866 ?
CPS2 384x224 @59.64Hz	512 / 262 / @8MHz	384x240
PC-8801 640x400 @55.39z	848 / 525	480p	H.samplerate=848, H.synclen=64, H.backporch=80, V.backporch=38	Allow upsample2x might reduce noise
PC-98 640x400 @56.4Hz	848 / 525 / @21.0526MHz	480p	H.samplerate=848, H.synclen=64, H.backporch=80, V.backporch=32
PSP				See the dedicated page.

Horizontal multiplication factors

Frame width is multiplied by an integer factor defined below while picture area is multiplied by the value in parenthesis (if different) to maintain correct aspect ratio. Vertical multiplication factor is defined directly by line multiplication mode. For example, consider 320x240 in line3x mode. Frame size is multiplied by 4 in horizontal direction, and by 3 in vertical direction to generate a frame of 1280x720 which is ideal for 720p output. However, picture area is only multiplied by 3 in horizontal direction so that effective area (960x720) maintains 4:3 ratio of the source.

	512x240	384x240	320x240	256x240 (4:3)	256x240 (8:7)
Line2x	2x	2x	2x	3x	3x(2x)
Line3x	2x	3x	4x(3x)	5x(4x)	5x(3x)
Line4x	2x	3x	4x	5x	5x(4x)
Line5x	3x*	4x*	5x*	6x*	6x(5x)*
Line6x	4x	6x	6x	8x	8x(6x)

• With Line5x, horizontal active and mask are adjusted internally so that frame width of 1600 or 1920 (depending on "Line5x format") is always generated. In 1920x1080 format, vertical active and backporch are also internally adjusted (-24 and +12) to generate suitable frame height.

The FirebrandX optimal timing method

Community member FirebrandX has produced a useful YouTube video tutorial on how to discover optimal video timings. This video can be viewed here.