01-20-2017 12:38 AM - edited 01-20-2017 12:43 AM
Hi folks,
Not sure about the HD PVR as I haven't confirmed its settings, but on the Nextbox 4K, the single best thing I did to improve video quality was:
Now, I know what you're thinking -- why would you pick 1080i, isn't it better to use 720p or 1080p, the "p" means they support a full resolution, full 60 frames per second, after all...
Well, according to previous forum posts, it used to be that some channels would broadcast in 1080i at 30 frames per second while others went 720p at 60 frames per second. But I have yet to find an HD channel that streams in 720p or 1080p on my box, let alone 60 frames per second. Even the sports channels I tried (again, not all of them), would stream in 1920x1080, interlaced, at 29.97 frames per second (which rounds up to 30 for shorthand).
Okay, so now you might be thinking: but if I set it to 1080p at 60 frames per second, doesn't that mean I'm getting every frame of your 1080i signal, just doubled or something? Sort of -- there's a conversion going on here, but it's not entirely from 30 to 60 frames per second. Instead, it's a de-interlacing, which means every two frames are combined into one frame by the processor in the Nextbox 4K.
Now, this sort of de-interlacing can be unnoticable, but from what I can tell, the box is *terrible* at it. Content can seem to flicker or get mushy; or will appear clear when nothing's happening, but edges or contrast might get slightly pixelated when there's a lot of motion. For more on de-interlacing, and why it's best to never convert interlaced footage to progressive, see Wikipedia or the examples of interlaced "blur" at http://www.onlinevideo.net/2011/05/learn-the-basics-of-deinterlacing-your-online-videos/
The best way to "de-interlace" footage is to show it on the big screen, and transmit it there in its raw, interlaced glory. And so, I have a feature suggestion: allow me to set the NextBox 4K to decode the MPEG2 frames with "passthrough" settings: to dynamically change resolutions and interlace settings based on the primary (full-screen) video being displayed.
Now, the default, which might currently be 720p, I would change to 1080i and encourage folks to keep it at that setting *until HEVC becomes more common and interlacing is dropped from channel signals* but it's even easier to have a setting that is called "dynamic - up to 1080p" or "dynamic - up to 1080i" and use the appropriate resolution on every channel change. A dynamic setting would also allow for easy switching from 4K to 1080i without having to go to the Settings menu every time, that said, maybe this is already possible? (I don't yet have a 4K TV.)
I'd also like to know why the 30 second skip forward button on my new RF remote control is not enabled when the skip back button obviously works. 🙂
Finally, why can't I plug in a USB key and backup my recording/PVR settings to it? Or transfer all recordings & settings to an external hard drive for easier replacement of PVRs? Obviously future IPTV PVRs will never need this -- I figure by then we should just have PVR functionality off-site in the cloud, and your "recordings" are nothing more than bookmarks on previously recorded and ready-to-stream content.
And one last thing -- any timeline for switching from poor MPEG2 encoding to something better like MPEG4 or HEVC in 1080p? I mean, yes, you can get some amazing results with MPEG2 1080i, but it makes hand-held footage of busy scenery look absolutely terrible. By comparison, HEVC dynamically adjusts how much data it encodes in each frame, which is horrendously complex, but indicates just how much better encoding has become since MPEG2 was state-of-the-art: https://sonnati.wordpress.com/2014/06/20/h265-part-i-technical-overview/
Need I remind folks that MPEG2 is what's used on DVDs? So if you've ever felt like your HDTV was playing back slightly more detailed DVDs, this is why -- why Blu-Ray, Netflix and YouTube all look nicer than most people's HDTV streams. For the best mix of compression and image quality, cinemas actually encode videos as a series of JPEG 2000 photos, for practically lossless encoding. That would be the opposite of MPEG2, or the sometimes mushy video we're stuck with currently.
But enough ranting from me. Any thoughts? Did 1080i improve things for you too? Try a few different video settings and see what you get. Pay close attention to sports channels or wildlife channels. Watch CP24 or other news channels and look at how smooth text might fade or appear. Also remember that your TV has picture settings that can interfere with the image -- smoothing or sharpening the image unexpectedly.
Louis.
01-20-2017 12:42 AM - edited 01-20-2017 12:43 AM
One last thing, in regards to image quality, on radX (and possibly other channels), I'm noticing that the ads inserted into the channel from Rogers look much nicer and clearer than the content it's been playing for hours. Is it possible that some channels are double- or triple-encoded while other sources, like ads, are encoded just the once for delivery over MPEG2?
01-20-2017 12:03 PM
01-20-2017 12:17 PM
01-20-2017 01:03 PM - edited 01-20-2017 01:04 PM
01-20-2017 01:45 PM
01-20-2017 05:58 PM
With a nextbox 3.0 I agree, set it to 1080i output. You want the least amount of conversion as posible, and 99% of HD channels are brodcast in 1080i. (fox and abc are 720p). Rogers receives the hd stream in 1080i, then broadcasts it in 1080i, then the box outputs it to the tv in 1080i. This is the best setup since the only conversion is in the tv when it outputs to it's native res, which is usually 1080p.
However if you have a 4k Nextbox then I would assume you got it because you have a 4k tv that you spent good money on. In that case set it to UltraHD output, because setting it to any thing else (1080p, 1080i, 720p) is a waste since you arent getting the 4k resolution that you paid so much for. 4k Nextbox's should always be set to UltraHD output when connected to a 4k TV!
Also I doubt Rogers is changing from MPEG-2 or changing QAM settings, as they're going to launch X1 in 2018 as mentioned, so they're not going to waste resources on the current setup.
01-20-2017 06:03 PM
01-21-2017 03:47 AM - edited 01-21-2017 03:58 AM
01-21-2017 08:30 AM
History lesson:
The old 8300HD PVRs did passthru resolution (changed the box's resolution based on the input).
People complained non stop that they didn't have an HD guide.
With NextBox 2.0 and the RTN guide, Rogers gave people an HD guide, but had to do it by fixing the displayed resolution.
...and now people are complaining.
In short, Rogers can never win.
01-21-2017 08:31 AM
@LSTA wrote:
Interesting responses. Okay then. I'll simply say two things: 1. I've the 4K box because the picture is better on 1080 output--I don't have a 4K TV, but I can see and likely measure the difference the box makes, even over 1080. 2. Even if I had a 4K box, how does watching a 1080i stream in 4K improve things when it's just the box doing the conversion from 1080 interlaced to progressive?
I'm not 100% sure QAM256 is new to the new boxes, I'll have to check once more. But the 1080 picture looked clearer on the 4K box and it was faster to switch channels, etc.
I don't really need 4K until widely available content and OTT boxes catch up later this year, but I do like this 4K PVR for plain 1080 watching! 🙂
I'm surprised you have a 1080p TV and say the 4k box when set to 1080i looks better than a nextbox 3 set to 1080i. Because they should be outputting the same source/input signal without any conversion, 1080i signal from rogers broadcast in, 1080i out.
If you have a 4k tv and 4k nextbox then setting it to 1080i or 1080p wont get you the 4k signal, this is why you have to set it to UltraHD, so you can take advantage of the 4k channels. And for me 4k channels and regulaur HD channels look great on my Samsung KS8000 with the 4k box set to UltraHD.
01-21-2017 08:33 AM
@Lurker wrote:History lesson:
The old 8300HD PVRs did passthru resolution (changed the box's resolution based on the input).
People complained non stop that they didn't have an HD guide.
With NextBox 2.0 and the RTN guide, Rogers gave people an HD guide, but had to do it by fixing the displayed resolution.
...and now people are complaining.
In short, Rogers can never win.
Yes, I actually miss that feature because I set it to passthrough so it would display 1080i, or 720p depending what channel I was watching. It would be nice if Rogers could do that with the new boxes for the HD and UltraHD channels. That way they can make a 4k format guide, and scale to a 1080i/720p format guide, and let the signal passthrough so the TV does the final conversion.
01-21-2017 08:41 AM - edited 01-21-2017 08:48 AM
01-21-2017 08:46 AM
01-21-2017 08:49 AM
01-21-2017 02:38 PM - edited 01-21-2017 02:40 PM
01-22-2017 02:42 AM - edited 01-22-2017 02:48 AM
Introduction
Okay, I'm reporting back after having done more tests head-to-head with the 4K PVR and the Nextbox 3.0 HD PVR, such as by watching and recording the same live TV program.
1. HD vs 4K PVRs, not so different--Both have terrible MPEG2 compression.
I can confirm that in settings, both PVRs show they are capturing at QAM 256, and that the blurriness I was seeing on the HD PVR was actually MPEG2 compression applied equally horribly to both boxes, and varies from scene to scene.
The best quality is content that is easily compressed: simple line art in animated cartoons, for example, or still photographs in a Ken Burns style, or interviews/talking heads on a blurry or simple background.
What looks terrible is wide arial shots from above, moving or hand-held camera, or animations where everything is in motion on sceren because the camera is "panning" quickly. As it happens, I'm perhaps more sensitive than most to this kind of issue. What also looks especially terrible is already-compressed footage, like when a documentary shows footage from a camcorder or cellphone, or if a show or channel is streamed with compression to Rogers, and then Rogers re-streams it applying further compression. I can't yet pinpoint this, because I've yet to see any content without noticable compression artifacts and blurring, so it's hard to say whether I'm seeing a double-compressed channel, or simply content that reacts better or worse to the MPEG2 compression Rogers uses.
2. Further thoughts on 1080i vs 1080p, it's about life-like motion
I can say that 1080i vs 1080p shows more with some content. It's less about compression though, here it's more about the smoothness of motion, and how true-to-life it is. Motion in 1080i from a source that's 1080i is going to feel more life-like. If you hit the Replay button and watch the same scene in 1080p when the original was interlaced, you'll find that you're more confused during motion as to what's happening on-screen. Let me rephrase this: with an interlaced source, and very rapidly changing pixels on screen, the progressive display of such a source has to be de-interlaced, which means pretending or predicting what half the screen should look like based on what came before.
When interlaced, this artificial prediciton or timing change doesn't occur and instead you see basically just the pixels you were meant to see. It's true, in 1080i, the guide doesn't look as nice because you've only half the pixels to work with in one direction, but the smoothness of motion more than makes up for this. You can notice this easily in shows like Archer with complicated backgrounds that animate smoothly -- it looks more smooth in 1080i than 1080p. You can also notice this in nature documentaries involving bubbling water or irregular motions of wind -- with 1080p I found myself distracted, counting water ripples in surprise, but with 1080i it was smoother, instead of paying attention to each ripple, I was noticing the source of the ripples and able to predict the next one myself.
3. Thoughts on 4K/HD PVR hardware internals -- is the 4K PVR technologically worth it?
That said, while 1080i helps, the lack of difference between HD and 4K PVRs indicates to me that the only advantages the 4K PVR has is speed: the HD PVR has a 3000 DMIPS speed processor included in the SoC https://www.broadcom.com/products/broadband/set-top-box/bcm7425 while the Technicolor CAV10455 has a 12000 DMIPS dual-core processor that's both 4 times faster and dual-core, so better able to multi-task.
The 4K PVR (CAV10455) doesn't list its processor, but the only SoC with MoCA support that I could easily find on Google with a 12000 DMIPS processor is STM's STiH418, and I'm seeing references in blogs & LinkedIn that Technicolor used this chip in trials in France. STM appears to be withdrawing from set-top boxes, so it's possible future Technicolor STBs will use Broadcom designs.
Of course, thanks to standards, an ARM chip is an ARM chip, and while a 12,000 DMIPS design is slower than the 21,000 DMIPS chips Broadcom is now producing, it's still faster than the 2012-era 3000 DMIPS boxes. The HD PVR has 1 GB of DDR3, the 4K PVR if I'm reading the diagnostics correctly, also has only 1 GB of DDR3.
So I wouldn't expect any fancy new apps or web browsing to appear on these PVRs anytime soon. And given that the hard drive inside is unchanged, just 1 TB, I'm starting to think that $499 is overpriced for this kind of technology. For example, if I've done the math correctly, the 12,000 DMIPS processor inside here is barely faster than an iPhone 5. Based on noise and heat, looking down on the 4K PVR from above, the hard drive is on the left side while the SoC and mainboard are probably occupying 3-4 inches across on the right side. There's no air movement, just the clicking of a hard drive, so it's passively cooled.
Cheapest price I could find on a 1TB HDD is $45. Add another $150 for the system boards, $50 for the housing, remote and cables, and I'm betting Technicolor can build one of these for $150-250, sells it to Rogers for $250-350 and Rogers then re-sells it for $500 or $25/month, whatever it can get away with. The real profit lies in convincing folks to pay $4/channel under the new pricing when Rogers pays at most 40¢/channel for most channels.
Conclusion: Until Rogers upgrades 1080i to HEVC 1080p, ignore the 4K PVR if you don't care about 4K channels
I suppose what I'm doing here is trying to convince myself that if I have a plan with a discounted HD PVR, I shouldn't bother getting the 4K box until Rogers improves its codecs from MPEG2 to nicer-looking HEVC for all 1080p channels. Until that time, I'll just be distracted by the alternating great-looking and horrible-looking MPEG2 compression, and that's really the enemy here. 🙂
01-22-2017 09:59 AM
01-24-2017 11:06 AM
01-24-2017 06:43 PM
@toolcubed wrote:
Why not have a "pass through" option for the NB3 and 4K boxes? Is it a limitation of the software (Navigatr) or the hardware? I understand that Rogers broadcasts most channels in 1080i so setting the NB3 to 1080i is best but what about those channels that are 720p? Or the OnDemand content that's 1080p? Keeping the box at 1080i means the content is scaled down or up by the box and then again by the TV...not good. Pass through would allow the box to just pass the signal straight to the TV regardless of what it is from the channel.
I would love that feature as well. However at this point Rogers wont spend the resources on a dying platform. Next year we will get hybrid iptv using the comcast X1 platform.
01-26-2017 12:50 PM