This commit adds both a 480p input sampling mode and line2x optimized
mode for the PSP's 480x272 picture. The line2x optimized mode is enabled
automatically when the sampling mode is selected.
When in-game, the PSP outputs a letterboxed 480p picture. The active
portion of the screen is 480x272, but is treated as 480p (480x720).
In addition, a line2x optimized mode is added which produces a 960x544
output picture, which if desired the top + bottom pixels can be dropped
producing a 960x540 (qHD) picture.
To generate a qHD picture, use the following settings:
V. Active: 270
V. Backporch: 135
* Disable 480p scanlines in auto mode
* Remove inoperable 3x/4x processing modes from 1080i list
* Add 640x512 mode to 480p group and limit 480p sampler option to 525-line modes
* Fix occasional pixel repetion issue after HDMI<->DVI TX switch
* Add "Allow upsample2x" option
* Add comments to some unclear sections
* workaround for phase shift issue on optimized modes
* add hscale option for 256x240 opt Line3x mode
* distribute video modes to groups and allow passthru for all modes
* Improved remote control handling code
* Fixed occasional mode change loop when switching to a non-interlace mode utilizing odd-field sync signal
* Fixed randomly missing blue channel at power-on when using DVI output mode
* Added H-PLL coast options
* Finer tuning range for scanline strength and mask
