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<blockquote data-quote="haggard" data-source="post: 155403" data-attributes="member: 183237"><p>To explain 4.2.2 and 4.1.1 etc would take a long tutorial. If there's a wish I can write one that is technically correct.</p><p>For here, cutting corners:</p><p>To record or transmit an RGB pic at top resolution takes far too much bandwidth. So although the pics we get are 720x576, there is some averaging/compressing, spatial and temporal, to get the stream down to e.g. 4Mbps.</p><p>Full RGB is called 4.4.4 because averaging is usually done on a block of 4 pixels (2x2) and there is no averaging in RGB i.e. 4 R pixels, 4 G pixles and 4 B.</p><p>Now it has been long known that the eye is more sentive to b/w (called Y) so it is usual to record/TX all Y pixels. </p><p>Therefore before recording or TXing, the colour space is rotated from RGB into (say) YUV. Y is now R+G+B. The other two components are chosen to be the ones that fox the eye best. Studio recordings and live txs are moved about in 4.2.2 which means there is horizonal averaging of 2 pixels in the 2x2 block. This is the format on e.g. a digital beta tape. This is what is shipped in a 4.2.2 TX, the sort you are talking about, 4 Y pixles, 2 U pixels and 2 V pixels per block of 4.</p><p>mpeg2 does even more averaging over the 4 pixels and you will typically get 4.1.1 which means 4 b/w pixels bit just 1 each of the colour combinations in a block of 4. DVD is the same. "PAL" is less compressed than "NTSC". The quotes means that the terms PAL and NTSC are legacy names because the encoding is no longer old PAL.</p><p></p><p>Now hear this. If you want to watch 4.2.2 at home, you will need something that will convert it into a stream understood by your receiver, PC or Mac or TV. e.g. I have a YUV input to my TV but the receiver (D<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite6" alt=":cool:" title="Cool :cool:" loading="lazy" data-shortname=":cool:" /> converts the mpeg to analogue YUV. YOu may have a brill receiver or nice software but it is probably not as good as the pro converters that change 4.2.2 into mpeg at the uplink or transmitter. Therefore 4.2.2 might look worse! If you can do 4.2.2 -> digital monitor, then you would not complain!</p></blockquote><p></p>
[QUOTE="haggard, post: 155403, member: 183237"] To explain 4.2.2 and 4.1.1 etc would take a long tutorial. If there's a wish I can write one that is technically correct. For here, cutting corners: To record or transmit an RGB pic at top resolution takes far too much bandwidth. So although the pics we get are 720x576, there is some averaging/compressing, spatial and temporal, to get the stream down to e.g. 4Mbps. Full RGB is called 4.4.4 because averaging is usually done on a block of 4 pixels (2x2) and there is no averaging in RGB i.e. 4 R pixels, 4 G pixles and 4 B. Now it has been long known that the eye is more sentive to b/w (called Y) so it is usual to record/TX all Y pixels. Therefore before recording or TXing, the colour space is rotated from RGB into (say) YUV. Y is now R+G+B. The other two components are chosen to be the ones that fox the eye best. Studio recordings and live txs are moved about in 4.2.2 which means there is horizonal averaging of 2 pixels in the 2x2 block. This is the format on e.g. a digital beta tape. This is what is shipped in a 4.2.2 TX, the sort you are talking about, 4 Y pixles, 2 U pixels and 2 V pixels per block of 4. mpeg2 does even more averaging over the 4 pixels and you will typically get 4.1.1 which means 4 b/w pixels bit just 1 each of the colour combinations in a block of 4. DVD is the same. "PAL" is less compressed than "NTSC". The quotes means that the terms PAL and NTSC are legacy names because the encoding is no longer old PAL. Now hear this. If you want to watch 4.2.2 at home, you will need something that will convert it into a stream understood by your receiver, PC or Mac or TV. e.g. I have a YUV input to my TV but the receiver (DB) converts the mpeg to analogue YUV. YOu may have a brill receiver or nice software but it is probably not as good as the pro converters that change 4.2.2 into mpeg at the uplink or transmitter. Therefore 4.2.2 might look worse! If you can do 4.2.2 -> digital monitor, then you would not complain! [/QUOTE]
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