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Reply To: Dreamcast – VGA or DTV 480p confusion

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#8738

marqs
Participant

TVs normally scale Rec. 601 720×480 either to 4:3 (standard) or 16:9 (anamorphic widescreen) based on which one user selects as aspect ratio. As show in the previous picture, DC outputs only 640×480 subsection (which is designed to fill whole 4:3 screen) within that area so it won’t result to correct aspect with modern displays by default. However, recent OSSC fws have advanced timing tweaking option which can reduce the width of signal marked as active from 720 to 640, so monitors and compatible TVs can display only that area when scaling to 4:3 or 16:9 (widescreen games), resulting to exactly correct aspect ratio. Note that the mode is not same as VESA 640×480@60Hz which has different sampling rate.