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Playback Issues
With several channels of audio from the DVD, the cabling needed to carry the signal to an amplifier or TV can occasionally be somewhat frustrating. Most systems include an optional digital connector for this task, which is then paired with a similar input on the amplifier. The physical connection is typically RCA connectors or TOSLINK, which transmits a S/PDIF stream carrying either uncompressed digital audio (PCM) or the original compressed audio data (Dolby Digital (AC-3), DTS, MPEG audio) to be decoded by the audio equipment.
Video is another issue which continues to present most problems. Current players typically output analog video only, both composite video on an RCA jack, as well as S-Video in the standard connector. However neither of these connectors were intended to be used for progressive video, so yet another set of connectors has started to appear, to carry a form of component video, which keeps the three components of the video, one luminance signal and two color difference signal, as stored on the DVD itself, on fully separate wires (whereas S-Video uses two wires, uniting and degrading the two color signals, and composite only one, uniting and degrading all three signals). The connectors are further confused by using a number of different physical connectors on different player models, RCA or BNC, as well as using VGA cables in a non-standard way (VGA is normally analog RGB—a different, incompatible form of component video). Even worse, there are often two sets of component outputs, one carrying interlaced video, and the other progressive. In Europe (but not most other PAL areas), SCART connectors are typically used, which can carry composite, Y/C (S-Video) and/or analog RGB interlaced video signals (RGB can be progressive, but not all DVD players and displays support this mode), as well as analog two-channel sound on a single convenient multiwire cable. The analog RGB component signal offers video quality which is superior to S-Video and identical to YPbPr component video. However, analog RGB and S-Video signals can not be carried simultaneously, due to each using the same pins for different uses, and displays often must be manually configured as to the input signal, since no switching mode exists for S-Video. (A switching mode does exist to indicate whether composite or RGB is being used.) Some DVD players and set-top boxes offer YPbPr component video signals over the wires in the SCART connector intended for RGB, though this violates the official specification and manual configuration is again necessary. (Hypothetically, unlike RGB component, YPbPr component signals and S-Video Y/C signals could both be sent over the wire simultaneously, since they share the luminance (Y) component.) HDMI is a new digital connection similar to DVI; it carries High Definition, Enhanced Definition and Standard Definition video. Along with video HDMI also supports up to eight-channel digital audio. Some HDMI-equipped DVD players can upconvert the video to higher definition formats such as 720p and, more rarely, 1080p.
Na kratko. YPbPr je analogna video povezava, HDMI digitalna. Obema je osnova RGB. Kdor ima DVD s TV povezan prek kvalitetnega RGB Scart kabla (za 30€), več ne potrebuje. Ko zmanjka RGB Scart priključkov, je najbolje YPbPr Progressive + Avdio uporabiti za daljšo povezavo (10/15m do projektorja), HDMI za krajšo do rekorderja. Sicer pa med HDMI in YPbPr v kvaliteti slike ne bi smelo biti razlike, če sta oba kabla kvalitetna. Kvalitetni YPbPr in HDMI kabli stanejo 50€ in več.
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