Kevin Chen

One of my favorite creative uses of Excel comes from !!Con 2017, where Kevin Chen used spreadsheet to implement HDR imaging[1]. It’s also just an incredibly well-crafted presentation. [1] https://kevinchen.co/projects/excel-hdr/

> remember people saying the exact opposite It was a common but bad hypothesis. "If you had asked me in 2018, when I first started working in the AV industry, I would’ve bet that driverless trucks would be the first vehicle type to achieve a million-mile driverless deployment. Aurora even pivoted their entire company to trucking in 2020, believing it to be easier than city driving. ... Stopping in lane becomes much more dangerous with the possibility of a rear-end collision at high speed. All stopping should be planned well in advance, ideally exiting at the next ramp, or at least driving to the closest shoulder with enough room to park. This greatly increases the scope of edge cases that need to be handled autonomously and at freeway speeds. ... The features that make freeways simpler — controlled access, no intersections, one-way traffic — also make ‘interesting’ events more rare. This is a double-edged sword. While the simpler environment reduces the number of software features to be developed, it also increases the iteration time and cost. During development, ‘interesting’ events are needed to train data-hungry ML models. For validation, each new software version to be qualified for driverless operation needs to encounter a minimum number of ‘interesting’ events before comparisons to a human safety level can have statistical significance. Overall, iteration becomes more expensive when it takes more vehicle-hours to collect each…

- disk storage: depends what you're doing, but seems to be about 150MB / hour. This is WAY too much in my book. I think we could get this way down. I'd love help here too :D - Candidly, haven't done extensive testing in battery department, but someone posted an article in a sibling comment https://kevinchen.co/blog/rewind-ai-app-teardown/ and it said "Overall, running Rewind reduces my battery life by about 20–40 percent." - that's way too much imo. And I assume `rem` is in that ballpark, as based on this article, it's doing pretty similar stuff, though way fewer accesses to disk as I don't write screenshots to disk, just stream directly to mp4. But - I built it in a few days and haven't spent time on optimization. This can be clearly seen in the binary size too. First build I released was 165MB, and after I took a step back, fixed the build process, and built a custom build of ffmpeg, it's now 3MB. Seeing as Rewind is a 211MB dmg, they aren't doing a ton of optimization either, so I think there's tons of room for improvement.

Privacy issues aside, it's really cool to see a new category of device! I've been actively searching for something that will allow me to "write" my essays while I'm driving. I've tried voice memo apps for iOS, and the transcription stinks for everything I've tried. Rewind's transcriptions for meetings works great, so I'm cautiously optimistic --- Sidenote: I've been loving Rewind as a company, but I'm a bit worried about how they're approaching security. They store fantastic metadata[1] in their sqlitedb locally, but they recently started encrypting the DB, which is great, BUT I want to be able to poke around and see EXACTLY what's being recorded. [1] https://kevinchen.co/blog/rewind-ai-app-teardown/ I've been trying to get a script like the following working, if anybody has pointers! sqlite3 -readonly -bail -hexkey $(security find-generic-password -w -a '' -s ai.rewind.data-account) \ ~/Library/Application\ Support/com.memoryvault.MemoryVault/db-enc.sqlite3 -cmd .tables

They didn't have their own compression algorithm; they used ffmpeg to compress screen recordings to MP4 files at 0.5 FPS. https://kevinchen.co/blog/rewind-ai-app-teardown/

Is that "same direction travel divided between autonomous trucks and all other traffic"? Or "only on highways where traffic directions are separated by a median"? The former sounds like a massive (understating it probably) infrastructure investment. Trains sound better (as other comment while I was typing notes). The latter doesn't solve the issues noted in the recent article here: https://kevinchen.co/blog/autonomous-trucking-harder-than-rideshare/ Am curious to hear more thoughts/insights.

I suspect it's Apple Silicon only because there are simple APIs that Apple has provided to take screenshots of the desktop and OCR text from images. I don't think OP necessarily built any low-level code from scratch here (not that their provided code isn't useful). Someone else has previously looked into how Rewind.ai may be doing its thing under the hood and there are more details about it here: https://kevinchen.co/blog/rewind-ai-app-teardown/ OP may have used some of the info there.

The default in Redis changed, as a result of active exploitation: https://kevinchen.co/blog/postmortem-server-compromised/

Here you go: https://kevinchen.co/blog/postmortem-server-compromised/

Serious lapses on the parts of PayPal and GoDaddy. Ironically, there are sites which even refuse to identify the real person - like this one posted on HN a few days back(http://kevinchen.co/blog/square-identity-verification/)