Originally Posted by ashyt16
I would have thought if there are enough cables there already it would be feasible to use them to knock up some sort of DIY converter. I wouldn't go to the expense of buying that one linked above and neither would I go backwards and use component rather than HDMI/dvi. That's a backward step to me and I have come to appreciate the difference a digital connection makes over analog.
Let's go through the signal chain and see how component video and HDMI video differ. When a Roku (with component video ports) or DirecTV STB or streaming box gets a signal into it, the video portion is compressed digital since we have no transmission method to send an uncompressed digital signal. So MPEG2 or h.264 or AVC comes into the box. The first thing the box has to do is to convert into an uncompressed video signal.
If no modifications to the video signal are required, this uncompressed video signal can be sent directly to the HDMI port. The uncompressed signal can also then be sent over component video using a D/A converter. Note that in both cases the same digital signal is being used as a source. The only difference is that the digital signal is being converted to analog in set top box / receiver.
When the TV, receives the HDMI signal. The signal then gets converted to analog in any typical flat panel. This analog signal is then sent to the panel electronics which generates the picture.
With the component video signal the analog signal is sent to the panel electronics for display. So, the D/A conversion is being done in the case of the TV.
The bottom line is that HDMI or component, it's the same source signal.
You are probably saying, but wait what about 1080p? There is no electrical reason 1080p can't be sent by component video. I have TVs that will accept 1080p over component video.
But the important thing about 1080p is that for the most part it's only Blu-Ray (and HD-DVD) that have native 1080p content. DirecTV and almost all streaming systems either send 1080i or 720p and then the receiving box converts to 1080p. There is just too much wasted bandwidth sending a 1080p signal that any good deinterlacer can turn into good 1080p. So services don't do this (bandwidth is money - particularly with DirecTV).
So, 1080p can be sent over component video (if the manufacturer desires or is allowed) and most content is not sent as 1080p.
In the end, the difference between HDMI and component video is where the D/A conversion occurs. With component video the conversion occurs in the player, with HDMI the conversion occurs in the TV. If you have a $50 streaming player, then its conversion is likely to be poor compared to a $2K TV. That's where the difference occurs.
But, in general, the 720p or 1080i picture over HDMI should match the 720p or 1080i picture coming from a component video cable. In the mid-2000s, it was very often true that the component video picture was better than the HDMI picture because the HDMI chipsets were so poor and overheated a lot. That's changed now so that component video and HDMI HD video should look the same, if both are tuned properly.
BTW, HDMI is sent at 10.2 gbps (and soon 18 gbps). It uses 19-conductor wire. So, to use 4 coax or 4 or any type of cable requires some type of conversion since that would only be 8 conductors. The argument you read was about whether a particular type of cable could support a 340MHz bandwidth (needed for 10.2 gbps) or not.