Hacker News: drmpeg

New comment by drmpeg in "H.264 Is Magic (2016)"

drmpeg — Thu, 29 Oct 2026 21:12:18 +0000

Using multiple CPUs for encoding goes way back. The early (1994) C-Cube MPEG-1 and MPEG-2 real-time encoders for DirecTV were built with 8 chips running in parallel (out of necessity since they were only 60 MHz processors) to encode 704x480. Each chip encoded a slice of the image and an auxiliary bus was used to send reconstruction video between chips so that motion vectors could cross chip image boundaries.

Here's a picture of the VME bus development board. It was a two board sandwich to support 10 chips in parallel (only one board pictured).

https://www.w6rz.net/scorpio.jpg

The first real-time HDTV encoders for terrestrial digital television (ATSC) were built by Harris using an IBM encoder chip. It took 6 chips to encode 1920x1080. The IBM chips didn't have an auxiliary bus, so you could see motion vectors limited to chip image boundaries (in this case, 6 tiles arranged like so).

  -------------------------
  |       |       |       |
  |   1   |   2   |   3   |
  |       |       |       |
  -------------------------
  |       |       |       |
  |   4   |   5   |   6   |
  |       |       |       |
  -------------------------

New comment by drmpeg in "Scientists solve 1840s space weather mystery"

drmpeg — Tue, 29 Sep 2026 00:12:06 +0000

There's never been a recorded S5 solar radiation storm. The highest level recorded was 43000 or S4 back in 1991. Another S4 storm occurred recently back in January 19, 2026 with a recorded flux of 36976.133.

https://www.spaceweatherlive.com/en/solar-activity/top-solar...

New comment by drmpeg in "How we used to get jobs: A newspaper classifieds story"

drmpeg — Wed, 12 Aug 2026 01:07:15 +0000

In 1981, my first job in Silicon Valley was obtained by answering a blind (no company name) ad in the Mercury News. It was a kooky company that built burn-in ovens for semiconductors (mostly 2164 memory chips back then).

I had a lot of fun there. The purchasing manager was a Scottish guy and he had an after hours drinking club in a small conference room with a wet bar. I was only 24 years old and working crazy hours. I'd get a few beers around 7 pm and then go back to work writing 8080 assembly language code for a few more hours.

I also ended up smoking weed with the CEO and CFO a couple of times. The CFO was not a young guy. I'm not sure how old he was, but he had all white hair. The CEO gave me a mason jar full of his homegrown weed as a gift when I finished the project.

That company and even the building is long gone. It's now a Google parking garage.

New comment by drmpeg in "It's a shame what's happened to radio"

drmpeg — Wed, 22 Jul 2026 03:48:22 +0000

I'll never forget Dennis Erectus on KOME 98.5 (the wet spot on your dial) in 80's Silicon Valley.

New comment by drmpeg in "The Last MPEG-4 Visual Patent Has Expired"

drmpeg — Mon, 20 Jul 2026 03:41:54 +0000

For sure. Just YouTube alone is a vast ocean of H.264 bits.

New comment by drmpeg in "The Last MPEG-4 Visual Patent Has Expired"

drmpeg — Sun, 19 Jul 2026 22:25:17 +0000

MPEG-2 video is still very much alive. In the US, almost all terrestrial OTA broadcast (ATSC 1.0) and all SD channels on cable systems. Even Comcast VOD was all MPEG-2 (including HD) until they shut down the QAM version in 2023.

New comment by drmpeg in "Nintendo Wii U games running from a 1980's Bernoulli disk [video]"

drmpeg — Tue, 23 Jun 2026 02:06:42 +0000

I was the project engineer for the Air Force Space Command / NORAD DSP satellite ground network back in the 80's. The system used the 10MB 8" Bernoulli drive and cartridges to store the early warning message traffic. The system was installed in 1988 and was decommissioned around 2005.

I'm not sure if they used the 8" cartridges all the way to 2005, but I can find out. I'm still friends with the original system maintainer. I pivoted to video compression in 1993 and lost track of the program, but we found each other on Facebook in 2010.

New comment by drmpeg in "I admire Fabrice Bellard. He is almost certainly a better overall programmer"

drmpeg — Tue, 16 Jun 2026 11:22:25 +0000

Advanced Television Systems Committee. It's the US standards organization for terrestrial digital television. ATSC 3.0 is a new standard that's very similar to DVB-T2 (used in the UK for HDTV) at the PHY layer.

New comment by drmpeg in "I admire Fabrice Bellard. He is almost certainly a better overall programmer"

drmpeg — Tue, 16 Jun 2026 09:36:04 +0000

Little known Fabrice Bellard project. He worked with the ATSC to test the ATSC 3.0 PHY layer when he was consulting at DekTec.

New comment by drmpeg in "Eight More '8-Bit Era' Microprocessors"

drmpeg — Mon, 11 May 2026 09:42:17 +0000

The article kind of disses the Intel 8085. For those of us with 8080 code bases that were never going to be rewritten for the Z80, it was a welcome upgrade. On the paper dryer process control systems I was working on in 1979, the 8085 based Intel 80/30 Multibus SBC could be dropped in for the older 8080 based 80/20 SBC with no changes and provide a significant 2.5X performance upgrade.

New comment by drmpeg in "Dirtyfrag: Universal Linux LPE"

drmpeg — Fri, 08 May 2026 07:42:21 +0000

Looks like the esp4 and esp6 fixes have been pushed for 7.0, 6.18, 6.12 and 6.6 kernels.

https://lore.kernel.org/lkml/2026050851-iron-hurdle-6421@gre...

https://lore.kernel.org/lkml/2026050843-unplowed-spinster-cf...

https://lore.kernel.org/lkml/2026050832-remold-faceless-bed0...

https://lore.kernel.org/lkml/2026050825-heaving-spender-13a8...

New comment by drmpeg in "An open-source 240-antenna array to bounce signals off the Moon"

drmpeg — Mon, 06 Apr 2026 05:37:22 +0000

Previous post.

https://news.ycombinator.com/item?id=45790672

New comment by drmpeg in "Using FireWire on a Raspberry Pi"

drmpeg — Fri, 27 Mar 2026 00:26:27 +0000

It's actively being maintained by Takashi Sakamoto. Here's the commit for Linux 7.0-rc1.

https://github.com/torvalds/linux/commit/0d6dd4738dbcc32b60c...

New comment by drmpeg in "A ternary plot of citrus geneology"

drmpeg — Fri, 06 Mar 2026 13:55:23 +0000

Meyer lemons from my backyard.

https://www.w6rz.net/lemons.png

New comment by drmpeg in "Time Station Emulator"

drmpeg — Tue, 27 Jan 2026 23:45:39 +0000

Here's an emulation of WWV I did with a transmit capable SDR.

https://www.youtube.com/watch?v=9LsJn0CyyZI

New comment by drmpeg in "Television is 100 years old today"

drmpeg — Mon, 26 Jan 2026 18:16:17 +0000

VSB came later. From https://www.tvtechnology.com/opinions/hdtv-from-1925-to-1994

In the United States in 1935, the Radio Corporation of America demonstrated a 343-line television system. In 1936, two committees of the Radio Manufacturers Association (RMA), which is now known as the Consumer Electronics Association, proposed that U.S. television channels be standardized at a bandwidth of 6 MHz, and recommended a 441-line, interlaced, 30 frame-per-second television system. The RF modulation system proposed in this recommendation used double-sideband, amplitude-modulated transmission, limiting the video bandwidth it was capable of carrying to 2.5 MHz. In 1938, this RMA proposal was amended to employ vestigial-sideband (VSB) transmission instead of double sideband. In the vestigial-sideband approach, only the upper sidebands-those above the carrier frequency-plus a small segment or vestige of the lower sidebands, are transmitted. VSB raised the transmitted video bandwidth capability to 4.2 MHz. Subsequently, in 1941, the first National Television Systems Committee adopted the vestigial sideband system using a total line rate of 525 lines that is used in the United States today.

New comment by drmpeg in "Level S4 solar radiation event"

drmpeg — Tue, 20 Jan 2026 00:32:44 +0000

Although everyone is interested in visible aurora, the proton flux is also really impressive. It peaked at 37,000 pfu at 1910Z. The highest ever recorded was 43,500 pfu in March 1991.

New comment by drmpeg in "More than one hundred years of Film Sizes"

drmpeg — Sun, 11 Jan 2026 12:14:13 +0000

VistaVision has made a comeback with "The Brutalist", "One Battle After Another" and "Bugonia".

https://en.wikipedia.org/wiki/VistaVision

New comment by drmpeg in "When square pixels aren't square"

drmpeg — Wed, 31 Dec 2025 16:13:47 +0000

Here's some captures from my Comcast system here in Silicon Valley.

https://www.w6rz.net/528x480.ts

https://www.w6rz.net/528x480sp.ts

New comment by drmpeg in "When square pixels aren't square"

drmpeg — Wed, 31 Dec 2025 15:15:00 +0000

> Videos with non-square pixels are pretty rare...

Before HD, almost all video was non-square pixels. DVD is 720x480. SD channels on cable TV systems are 528x480.