XSONY_NGUX
TK Veteran
Bit off topic but what do i scan to get this channel?Rambo in hd note the black bars top and bottom which is normal.View attachment 37614
User interface as i went back into mine a little tweak is needed as i have white space above my grey box which is the tv,ha ha picture must be rolling by itself from top to bottom and side by side so wont need any adjustments.View attachment 37615
Very interesting post, you said you have a 4k ARM box (a Gigablue) and the SD quality improved greatly when Broadcom released a new SDK and Gigablue implemented it in their drivers.I'm fairly sure the pixellation being discussed is the blockiness of an ugly upscaled SD picture rather than bad reception. The difference between various SD channels is very real.
The difference in SD quality between boxes is also very real and nearly always down to the scaling and deinterlacing algorithms used to convert SD (576i) to HD resolution for 1080p or 1080i (or 2160p) output. Aggressive sharpening is the worst culprit as the amount of bit-rate compression often applied to SD signals means that any fast movement or panning can create compression artefacts (blockiness) that is exacerbated by oversharpening.
A lot of this depends on the cpu being used (SH4 vs MIPS vs ARM...) and also the driver revisions (i.e., manufacturer implementation).
As an example, I have a 4k ARM box (a Gigablue) and the SD quality improved greatly when Broadcom released a new SDK and Gigablue implemented it in their drivers. I had both images on multiboot so could easily switch for a comparison. Night and day differences there. SD was poor before and very good now. HD quality at 1080i did not change but 1080p/2160p did change also as a different deinterlacing algorithm was used.
SkyHD boxes seem to give a rather soft SD picture which some find too soft but is more forgiving of an overcompressed (blocky) channel than boxes that sharpen aggressively.
By the way, all 28.2e HD is transmitted at 1080i, so if you output at 1080i you are leaving deinterlacing to your TV. Switching to 1080p simply moves the task of deinterlacing to your box which may do it better or worse than your TV.
Also worth noting is that if your TV is 4k and your box is 4k, if you output at 2160p then you are only upscaling once. If you output at 1080i/p then the box is doing 576i->1080i/p and then the TV is doing 1080i/p->2160p and you are upscaling twice.
TL/DR: The point is really, there are scaling and deinterlacing jobs being done, and your box may do these better or worse than your TV, so try all the settings and don't let anyone who has different equipment try to tell you that one setting is better than another. Only trust your own eyes.
As for HDMI cables, it is a digital bitstream that the TV can either lock onto or it can't. The 1's and 0's get there or they don't. It will not affect picture sharpness or how vivid the colours are, it is sending data. It's not like a SCART lead. Don't waste your money on fancy HDMI cables. Think about it, if HD is sharp, the UI is sharp, but your SD is crap, it's not the connection between box and TV.
A good test for SD bitrate if you have a Vermin line: when the footie is on Sky, compare Sky Sports Main Event to Sky Sports PL showing the same match. The SD on Main Event is very good and the same match on PL is rubbish, despite being the same resolution (but at a lower bitrate).
Most people seem to say that ARM (4k) boxes have better SD picture quality.
Sorry, didn't mean to get so carried away! :)
I have a Mut@nt HD51 do they also have a new SDK implemented in their drivers?
