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Add PAL and SECAM color system emulation #69
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Wouldn't this defeat the whole NTSC part of NTSC-RS? Good idea, but would it be a hz difference and resolution that can already be adjusted? |
Personally I don't see much of an issue, because I'm sure that there's a handful of people out there also wanting to emulate PAL/SECAM systems for authenticity |
What would be the differences besides the ones i listed though? |
Color spaces. While NTSC uses YIQ, PAL uses YUV and SECAM uses YDbDr. The better seems to be PAL, as with SECAM, we get the so-called "SECAM fire", whereas NTSC had the tinting issue, so PAL seems to be perfect (in fact, in Italy there was a dispute regarding adopting SECAM or PAL, but the latter was ultimately adopted and Italy, alongside the also-PAL Spain, introduced color broadcasts in 1972). Additionally, whereas the color in NTSC and PAL is amplitude-modulted, SECAM color is frequency-modulated, therefore making the ghosting (known on ntsc-rs as "ringing") only noticeable on luma, and not chroma like the other color systems. |
interesting! although I'm not sure what different color spaces would look like, I do know that the frequency-modulated signals should have a higher definition, right? |
Instead, frequency-modulated signals have better reception, with less ghosting. As states, YIQ (NTSC) has the tinting issue, YUV (PAL) seems to be perfect besides oversaturation on poor signal reception, and YDbDr (SECAM) produces red and blue snow, often known as the "SECAM fire". |
More detailed differences:
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I have made a fork named "pal-rs", but the only changed are in color space and chroma subcarrier, as it still has tinting issue simulation and still has the full vertical chroma resolution. |
should've seen it coming |
Oh, and on VCRs, there's a separate SECAM variant, named MESECAM. VHS SECAM (used in France) divides the chroma subcarriers by four (unlike the typical "630 kHz" method) on recording, and multiplies them by four on playback. In order to reduce costs for multi-standard VCRs, the Middle East and the Eastern Bloc, as well as any SECAM country but France, developed a separate variant: VHS MESECAM, which like VHS PAL and NTSC, uses the "630 kHz". Therefore, playing a MESECAM tape on a French SECAM VCR will only produce a monochrome image, and vice-versa. However, SONY later started manufacturing VCRs in France that support both French SECAM and MESECAM, as well as PAL (NTSC was also supported, but only for playback). |
As in the title.
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