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Generate video sprites using just FFmpeg

steelcm.com

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Re: Generate video sprites using just FFmpeg

#11

Post by JSR_FDED »

wslh wrote: post #6
bastloing wrote: post #3

Back in the day a sprite was a smaller 2d bitmap you'd superimpose on the screen. A key frame was a marker like this.

Yes, and the sprites were supported by a specific coprocessor. For example, the Apple II didn't have one.

We had to make do with Shape Tables in AppleSoft BASIC…good times drawing those out manually on graph paper. And then XOR-ing them onto the background. Amazing how good games were on the Apple ][ without dedicated graphics hardware.

Re: Generate video sprites using just FFmpeg

#12

Post by allenu »

EE84M3i wrote: post #9

Is it common to call these sprites in British English? I would call them "thumbnails".

I'll admit I was expecting an explanation of how to extract sprites from retro video game footage using FFmpeg, which I can see totally being possible with a bit of work.

Re: Generate video sprites using just FFmpeg

#13

Post by dlcarrier »

allenu wrote: post #12
EE84M3i wrote: post #9

Is it common to call these sprites in British English? I would call them "thumbnails".

I'll admit I was expecting an explanation of how to extract sprites from retro video game footage using FFmpeg, which I can see totally being possible with a bit of work.

I was thinking the opposite: Using FFmpeg as a sprite engine, to move sprites around, over background layers

Overlaying them at fixed positions is trivially easy, but animating the movement may take some work.

Re: Generate video sprites using just FFmpeg

#16

Post by jvan »

I've used vcs[0] to make contact sheets from videos. It has a nice feature that if it detects the frame is blacked out, it will shift the capture time so every frame on the sheet has something to look at. Easy syntax to set capture at every delta or capture x number of frames evenly distanced, columns per row, ignore a set length of end time, and frame size.

[0] https://p.outlyer.net/vcs

Re: Generate video sprites using just FFmpeg

#17

Post by steelcm »

pdyc wrote: post #14

interesting will probably integrate as sprite mode in my ffmpeg video editor https://newbeelearn.com/tools/videoeditor/

We're using this method as part of our user media upload pipeline at editsquare.com I'm guessing you're using ffmpeg wasm on your editor? One thing to note, that I didn't mention in the article, is generating a JPEG output is substantially quicker than a PNG.

Re: Generate video sprites using just FFmpeg

#18

Post by steelcm »

EE84M3i wrote: post #9

Is it common to call these sprites in British English? I would call them "thumbnails".

Maybe thumbnail sprite sheet is a more accurate term? I would have thought thumbnail on it's own doesn't represent the fact we're stitching together all the thumbnails of the video into a single image.

Re: Generate video sprites using just FFmpeg

#19

Post by steelcm »

jvan wrote: post #16

I've used vcs[0] to make contact sheets from videos. It has a nice feature that if it detects the frame is blacked out, it will shift the capture time so every frame on the sheet has something to look at. Easy syntax to set capture at every delta or capture x number of frames evenly distanced, columns per row, ignore a set length of end time, and frame size. [0] https://p.outlyer.net/vcs

This sounds like a more robust tool, however I wanted to keep our external tooling to a minimum. The contact sheet generation sits as part of our transcoding pipeline for uploaded media which already uses ffmpeg.
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