Broadcom LED displays - Page 1
Forum section: electronics / general

author: woodchips
author_rank: Frequent Contributor
timestamp: April 26, 2018, 07:30:54 pm
content: Used the HP/Avago 7 segment LED displays, in particular the HDSP-A103 low current one, for near 20 years.The latest batch purchased comes from Broadcom, whoever they are.Problem is that the old HP ones had a nice uniformly illuminated segment, the Broadcom ones have an obvious spot at one end of the segment. It looks really naff.Photo shows the old displays to the right, the new Broadcom on the left.Has anyone else experienced this disasterous drop in quality with other Broadcom displays?I have asked Farnell what goes, no doubt the answer will be to increase the forward current, in a battery powered device, really good idea!

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 27, 2018, 02:37:10 am
content: Broadcom is best known around here as the company behind the Raspberry Pi. Or in the past, infamous for buggy Wifi chipsets.

author: amyk
author_rank: Super Contributor
timestamp: April 27, 2018, 03:16:07 am
content: Quote from: NiHaoMike on April 27, 2018, 02:37:10 amAlso infamously secretive with the documentation for their products.I didn't know they made LED displays but the difference appears to be due to a smaller die (for cost reasons obviously) and insufficient diffusion. You could try adding another diffuser plate on top to compensate.

author: Mr. Scram
author_rank: Super Contributor
timestamp: April 27, 2018, 03:17:58 am
content: Quote from: amyk on April 27, 2018, 03:16:07 amYou can't let everyone know how crappy your products actually are.

author: ebastler
author_rank: Super Contributor
timestamp: April 29, 2018, 03:39:53 pm
content: Quote from: woodchips on April 26, 2018, 07:30:54 pmBroadcom = Avago = Agilent.Agilent's semiconductor division was spun out in 2005 and named Avago.AvagoacquiredBroadcom in 2015, and decided to change its name to Broadcom.Apparently a process change in whatever Avago foundry affected your LED displays. But it probably can't be blamed on (the former) Broadcom, who to my knowledge did not bring any LED product lines or factories.

author: amyk
author_rank: Super Contributor
timestamp: April 29, 2018, 05:02:52 pm
content: Quote from: Mr. Scram on April 27, 2018, 03:17:58 amWhat? Every product I have with an LED display, except some prototypes I built myself, has a red/green diffuser plate on top. It improves contrast too.

author: james_s
author_rank: Super Contributor
timestamp: April 29, 2018, 05:17:40 pm
content: Broadcom CPUs are in practically every domestic router and set-top box on the market, they're huge in the embedded world.I've used Kingbright LED displays in a few projects and have been very pleased with the look.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 29, 2018, 05:48:34 pm
content: Quote from: james_s on April 29, 2018, 05:17:40 pmQualcomm (a competitor they tried to buy) also has a very large share of the home networking market.I wouldn't be surprised if Broadcom dominates the budget media player market (that's a big consumer use case for the Raspberry Pi!), but at the high end, Nvidia is leading the way, only surpassed by full on HTPCs.

author: james_s
author_rank: Super Contributor
timestamp: April 29, 2018, 06:05:13 pm
content: I played with one of those Nvidia media players and was not terribly impressed. It seems to occupy a rather awkward segment, being far more expensive than the small embedded players including the RPi, while being less versatile than a fullblown HTPC without being all that much cheaper.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 29, 2018, 07:51:33 pm
content: Quote from: james_s on April 29, 2018, 06:05:13 pm$150 for a complete device that does pretty decent 4K upscaling is a decent deal. A low end GPU with equivalent capabilities is not very much cheaper, never mind the rest of the PC. Of course, the gamers and videophiles will go right for the full fledged HTPC.

author: Monkeh
author_rank: Super Contributor
timestamp: April 29, 2018, 08:54:27 pm
content: Quote from: james_s on April 29, 2018, 05:17:40 pm'practically every'. We'll just ignore: Marvell, Mediatek, Qualcomm, Realtek....Set-top boxes have an even wider range of chipsets.E: Oh, don't let me forget: Intel, Annapurna, Quantenna..

author: james_s
author_rank: Super Contributor
timestamp: April 29, 2018, 09:03:22 pm
content: Quote from: NiHaoMike on April 29, 2018, 07:51:33 pmI don't care about 4k, 1080p video looks just fine to me. If I wanted to upscale it I would just let the TV do the scaling.

author: rob.manderson
author_rank: Regular Contributor
timestamp: April 29, 2018, 10:19:14 pm
content: Jeez, I'm quite happy with 480P on a 55 incher (140cm)! Must be easily pleased

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 29, 2018, 10:31:43 pm
content: Quote from: james_s on April 29, 2018, 09:03:22 pmIf 1080p is all you need, a Raspberry Pi would be almost the ideal media center for you, unless you're into gaming.The upscalers that accept HDMI (that includes all TV upscalers except the ones used by smart TV apps running on the TV itself) will never work as well as those done by the media playback device because of the need to keep latency reasonable. Nvidia GPUs actually have two ways to scale - one in the output stage that is very low latency and works well for gaming, and the other is done by code running on the shaders which is used when latency is not important but quality is. The latter is the one mpv uses, while the former is set using nvidia-settings and applies to everything on the screen.Quote from: rob.manderson on April 29, 2018, 10:19:14 pmThere is a nostalgia factor to it, when the pixellation is part of the experience. Like how Minecraft intentionally uses very low resolution graphics.

author: rob.manderson
author_rank: Regular Contributor
timestamp: April 29, 2018, 10:39:26 pm
content: Quote from: NiHaoMike on April 29, 2018, 10:31:43 pmNah, it's just that I'm old enough to have spent most of my life watching 625 line PAL or Beta tape playback of same.But I do use a Raspberry PI as my media playback device - lovely little machine!

author: rdl
author_rank: Super Contributor
timestamp: April 29, 2018, 10:42:04 pm
content: I have plenty of DVDs I ripped that are only 480 vertical resolution (same as the original) and they are more than acceptable when played back on my 42" using VLC. I think I ripped most of them at around 1500 kbps. They probably look better than when originally viewed on a 27" TV with scan lines.

author: james_s
author_rank: Super Contributor
timestamp: April 30, 2018, 03:28:47 am
content: I've always been quite picky about picture quality, the difference between 480p and 1080p is substantial, the difference between 720p and 1080p is significant enough, but between 1080p and 4k I can barely tell.Regarding 480i SD content I think it generally looks terrible on a modern flat panel TV but I still have an old 27" Trinitron XBR CRT in the basement and it produces a fantastic picture with SD content. There is no pixelation with analog.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 30, 2018, 03:47:32 am
content: Quote from: james_s on April 30, 2018, 03:28:47 amTastyPC recently came back in 4K and the difference between actual 4K and 1080p upscaled to 4K was noticeable. An easy way to tell is to look at fine details like her hair - remember that the details 1080p was not able to capture cannot be put back by upscaling. (It's amazing how she manages to look flawless in 4K...)

author: james_s
author_rank: Super Contributor
timestamp: April 30, 2018, 06:20:46 am
content: How much real 4k content is there though? Most of the movies I own are still from DVDs, more recently I've been buying bluray versions but I'm not going to re-buy all the movies I already own. I have not yet seen an actual 4k movie, only some demo videos.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 30, 2018, 07:04:19 am
content: 4K is only going to increase in popularity as the cameras become cheaper. Remember the early days of 1080p?The way TastyPC suddenly came back in 4K got me by surprise. The question of when my GPU will get to run the fine tuned upscaler again (i.e. get new content that can actually make good use of it) is still open.

author: ruffy91
author_rank: Regular Contributor
timestamp: April 30, 2018, 08:28:27 am
content: Quote from: james_s on April 30, 2018, 06:20:46 amI regularly watch 4k HDR movies on our 65" OLED TV. (to be fair only ~50Mbit/s, Netflix). You wont believe me how good it actually looks. You can see the details in the shadows AND in the bright parts of the picture at the same time.To be fair though 1080p HDR looks good too, but the textures are not as sharp as with 4k video material.

author: james_s
author_rank: Super Contributor
timestamp: April 30, 2018, 05:06:19 pm
content: Well I'm sure some day I'll end up with a 4k TV but for now the 65" 1080p set I got for free and fixed has been working great. I'm not sure 4k movies are going to be worth the space on my Plex server but maybe hard drives will keep getting cheaper. From watching demos on 4k TVs I can make out the difference if I really look closely but it's incremental at best. Going from SD to 1080p was a very large improvement. I wonder what they'll try to come up with next? Hard to imagine much improvement beyond 4k.

author: dmills
author_rank: Super Contributor
timestamp: April 30, 2018, 05:29:45 pm
content: The consensus in the broadcast business is that HDR is a real improvement, 4k is great for monitors (where you are sitting close and the pixel scale works with the circles of confusion), but mostly a waste on a telly unless completely unreasonably sized.HDR, especially HDR that actually means it, lots of things sold as HDR do not manage the required brightness or required graduation in the black end of the scale, is a very clear improvement, 4k less so for telly.HDR also has the virtue that it can reasonably be compressed into a SDR image, so one camera and production chain can do both with some fiddling, the chain does not even need to be 4k capable, bog standard 3G-SDI will get her done, as 4k is basically a different gamma curve so new monitors and a new grading monitor, but all the switchers and routers can stay more or less unchanged.Regards, Dan.

author: Mr. Scram
author_rank: Super Contributor
timestamp: April 30, 2018, 07:28:39 pm
content: Upscaling is upscaling. Unless you unleash some neural network magic and actually fill in the detail, it's mostly just smoke and mirrors to fool yourself.

author: bd139
author_rank: Super Contributor
timestamp: April 30, 2018, 09:14:18 pm
content: Quote from: woodchips on April 26, 2018, 07:30:54 pmI noticed this as well. I bought one (different series) to replace a display in a clock my father built years ago.Intensity was focused on one side of the segment. Plus until I replaced it I didn’t see how orange the old displays had got. Ended up just buying 4 Kingbright displays. Much nicer and cost less than the single bloody Broadcom one.

author: dmills
author_rank: Super Contributor
timestamp: April 30, 2018, 10:27:25 pm
content: Quote from: Mr. Scram on April 30, 2018, 07:28:39 pmIt is **ALWAYS** smoke and mirrors! And then you take the upscaled video and stuff it into a statmux to spit out a few Mb/s for the uplink, grumble.Only thing is doing it offline lets you throw a lot more computational power at the problem, you can do things a deal smarter then just doing sinc resampling if you have the motion estimation vectors as well, but you really do not want to be doing that on live video, far better to work at offline rates.Regards, Dan.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 01, 2018, 12:33:10 am
content: Quote from: james_s on April 30, 2018, 05:06:19 pmYou can get 5K and even 8K displays right now, if you're willing to pay for it... Actually, I'm sure quite a few professional photographers already have one, since even a 8K monitor is not *that* expensive as far as pro budgets go. I like how displays are finally beginning to catch up to cameras as far as resolution goes.Quote from: Mr. Scram on April 30, 2018, 07:28:39 pmDetails that weren't captured in the original image will not be restored by upscaling. That can actually be a good thing sometimes - Britney Spears probably wouldn't look too good in 4K!http://www.marketwired.com/press-release/swanni-names-britney-spears-the-worst-looking-celebrity-in-hdtv-771598.htm

author: james_s
author_rank: Super Contributor
timestamp: May 01, 2018, 02:45:46 am
content: Displays sure, I'd love 5k or 8k on my desktop PC, but TV? I don't see 8k TV being a thing any time soon, as we've discussed here the benefits of even 4k are dubious. I like a good quality picture but I don't need to count the actor's nose hairs.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 01, 2018, 03:02:59 am
content: After watching TastyPC in 4K, 1080p just doesn't look the same anymore. Although I have to agree that 4K is pretty much well into the point of diminishing returns.A long time ago, I remember watching 240p video off a CD and thinking that was great quality. Which, to be fair, it was at the time.

author: Cubdriver
author_rank: Unknown
timestamp: May 01, 2018, 05:59:14 am
content: I love how a thread about poor uniformity in seven segment LED displays morphs into discussion of high resolution video formats.Ya gotta love thread drift.-Pat

author: Monkeh
author_rank: Super Contributor
timestamp: May 01, 2018, 02:46:03 pm
content: Quote from: Cubdriver on May 01, 2018, 05:59:14 amHe can't help himself.