Linux

48181 readers

1067 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Posts must be relevant to operating systems running the Linux kernel. GNU/Linux or otherwise.
No misinformation
No NSFW content
No hate speech, bigotry, etc

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago

MODERATORS

[email protected]

Extracting frames from a video with ffmpeg very slow if not using jpeg (discuss.tchncs.de)

submitted 4 months ago by [email protected] to c/[email protected]

28 comments fedilink hide all child comments

I'm trying to extract the frames of a video as individual images but it's really slow, except when I'm using jpeg. The obvious issue with jpegs is the data loss from the compression, I want the images to be lossless. Extracting them as jpegs manages about 50-70 fps but as pngs it's only 4 fps and it seems to continue getting slower, after 1 minute of the 11 minute video it's only 3.5 fps.

I suspect it's because I'm doing this on an external 5tb hard drive, connected over USB 3.0 and the write speed can't keep up. So my idea was to use a different image format. I tried lossless jpeg xl and lossless webp but both of them are even slower, only managing to extract at about 0.5 fps or something. I have no idea why that's so slow, the files are a lot smaller than png, so it can't be because of the write speed.

I would appreciate it if anyone could help me with this.

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] -2 points 4 months ago (1 children)

PNG is a good format for graphics, lettering, logos... not photography so unless your video is some cartoons you're using png compression for something is not meant for.

[–] [email protected] 3 points 4 months ago* (last edited 4 months ago)

I agree that you're not really leveraging any features of PNG like you would using JPEG or RAW here, but saying it's not meant for this use is an odd way to phrase it. There's nothing inherently wrong with wanting lossless compression on an image...