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killingtime74
I’m not in this field so... what alternatives are there? Write their own?
k_sze
My guess is that if FFmpeg didn't exist, they would still not try to develop the equivalent in-house. They might have licensed something commercial.
4gotunameagain
A similar example albeit an order of magnitude smaller: I work with a space instrument which includes a camera, and for various purposes some times we need to send down entire images. Due to the of course limited bandwidth, there is an option to compress the image to a jpeg and send it down. The jpeg compression is written from scratch.

Of course much simpler than ffmpeg and video encoding, but reinventing the wheel is not at all uncommon in aerospace (and curiously enough, reinventing the wheel is precisely what the entire sector is trying to avoid..)

k_sze
Huge congrats to Bellard and other ffmpeg contributors. This is a testament to the maturity and stability of FFmpeg. If FFmpeg were not mature or stable enough, it would never have been selected for use on Perseverance, because any bug that manifests itself while on Mars would be catastrophic, as there is a minimum of 6-minute roundtrip for light to travel between Mars and Earth.
lmilcin
You do understand they have ability to replace almost all of the software? So a problem with ffmpeg would be a nuisance at worst.
jimktrains2
While I agree that they're probably not running ffmpeg on a flight/control system and that they do update the software from the earth after launch -- in fact, they did it soon after landing to switch to the ground software from the flight software -- I think it's possible to be more generous to OP's overarching point: even if you can, you don't want to have to debug and update buggy software, even non-critical software, running on another planet and that ffmpeg's stability and capability make it an excellent choice.
liquidify
Only issue with ffmpeg that I've ever had is that there are hundreds of legacy blogs and stack overflow solutions that show some old version of how to use whatever feature I currently need.
mshachkov
I want to download the sequence of images (raw, unprocessed) taken by LCAM. Where (other then from "future" PDS release) can i download this sequence?
zootboy
https://mars.nasa.gov/mars2020/multimedia/raw-images/
mshachkov
Thx for suggesstion, but the images that can be downloaded out there aren't matching the description that is given at the article (they seems to be processed in some way), nor they are sequenced and can't to be downloaded in batch. Based on article, i am expecting to get 1024x1024 monochrome images.
MrSomeone
The LCAM data has been posted to the "raw images" site at the link below, although they do appear to be processed (contrast enhanced) so you may need to wait for the PDS release for the real raw data. You can tell by looking at the images before heatshield separation or after touchdown that they have been contrast enhanced (all images were taken at similar exposure times).

https://mars.nasa.gov/mars2020/multimedia/raw-images/?af=LCA...

earthscienceman
Hmmm. It says "designed to acquire audio events from parachute deploy to touchdown".

I assumed the reason they lost audio was because it wasn't designed for that and that it would have been lucky to keep it. Has anyone heard why they failed to capture during the EDL phase?

liquidify
They have certainly been vague on those details. I assume it is because they are investigating, but maybe they are trying to protect an engineering failure or some otherwise embarrassing detail from leaking. "Forgot to plug it in" might make for some ugly headlines. Probably better to just tell us already since it will inevitably come out.
proggy
Per Monday’s press conference, all of the EDL cameras and the microphone were commercial off-the-shelf products. They were lightly modified to reduce the likelihood of, say, electronic components off-gassing, but were not mission critical. They were simply put there to prove a point that, hey, if we want to do something cool and can’t justify the cost of bespoke hardware, we can try to use non-space rated hardware so long as we do no harm to the spacecraft or its mission objectives. I’d say the fact that all the cameras worked, and that the microphone came online during initial surface operations checkout (recording some very cool sounds from the surface), meant that the experiment was a rousing success.
ncmncm
If I recall correctly, the first Pioneer probe to Jupiter wasn't supposed to have a camera on board, because the chief scientist thought it would provide no information of scientific value. His objection was overcome.

Nobody in unmanned space exploration has been so spectacularly wrong on every level, since. (Manned, sure.)